目次〈特集〉
ソフィアシンポジウム
「SDGs の実現に向けて：森の生態系サービスを生かした持続可能な地域づくり」･
概要について･･････････････････････････････････････････････････････････････････････････････････････････････････････････････････ 柴田晋吾 （ 1 ）地球規模の政策目標を達成するための地域的アプローチ	 ･･････････････････････････････････････････････････････････････････････････････････････････････ ピーター ベッソー （ 5 ）森林カーボンオフセットプロジェクトの動機：
カリフォルニア・カーボンオフセット市場における環境社会的コ・ベニフィットの実証･･････････････････ エリン クロバー ケリー・マリサ ボンジョバンニ シュミッツ・･････････････････････････････････････････････････････････････････････････････････････････ アリール ワイスグロー （21）「生態系サービスへの支払い」（PES）により持続可能な地域づくりを目指す―タイにおける取り組みから･･････････････････････････････････････････････････････････････････････････････････････････････････････････････････ 柴田晋吾 （39）
〈論文〉
福島第一原発建屋内のたまり水の放射性汚染状況の解析（5）
･････････････････････････････････････････････････････････････････････････････････････････････････････････････････

大坪国順 （49）

環境ラベリング制度と持続可能な開発目標 (SDGs) の正の関連性の検討  
･････････････････････････････････････････････････････････････････････････････････････････････････ 蔡慧穎・鈴木政史 （67）
持続可能な開発目標と家族政策—育児休業制度の効果—
･････････････････････････････････････････････････････････････････････････････････････････････････････････････････

平尾桂子 （77）

並列均衡と交換経済 ･･････････････････････････････････････････････････････････････････････････････ 鷲田豊明 （95）

No. 14

2018年

Sophia Symposium 2018 “Sustainable Regional Development to Achieve UN SDGs by Utilization of Forest’s Ecosystem Services”････････････････････････････････････････････････････････････････････････････････････････････････････････････････････････････ Shingo Shibata(1)
Regional approaches to Achieving Global Policy Objectives･･････････････････････････････････････････････････････････････････････････････････････････････････････････････････････････････

Peter Besseau(5)

MOTIVATIONS FOR CREATING FOREST OFFSET PROJECTS: EVIDENCE OFENVIRONMENTAL AND SOCIAL CO-BENEFITS UNDER THE CALIFORNIA CAP-ANDTRADE CARBON MARKET････････････････････････････････････････ Erin Clover Kelly, Marissa Bongiovanni Schmitz and Ariel Weisgrau(21)
Pursuing Sustainable Regional Development Through “Payment for Ecosystem Services” (PES)-Implementation Status in Thailand････････････････････････････････････････････････････････････････････････････････････････････････････････････････････････････ Shingo Shibata

(39)



ArticlesAnalysis of time variations of radioactive substances in the ponding water in the main buildings of the
Fukushima Daiichi Nuclear Power Plant (5)･･････････････････････････････････････････････････････････････････････････････････････････････････････････････････････････ Kuninori Otsubo(49)
Exploring Positive Implications of Eco-labeling Schemes on Sustainable Development Goals･･････････････････････････････････････････････････････････････････････････････････････････････････ Huiying Cai, Masachika Suzuki(67)

Families and SDGs Goal 5:
Parental Leave Policies and Gender Equality･････････････････････････････････････････････････････････････････････････････････････････････････････････････････････････････････

Keiko Hirao(77)

Toyoaki Washida(95)

Parallel Equilibrium and Exchange Economy･････････････････････････････････････････････････････････････････････････････････････････････････････････････････････････

特集
ソフィアシンポジウム：「SDGs の実現に向けて：森の生態系サービスを生かした持続可能な地域づくり」
Sophia Symposium 2018:“Sustainable Regional Development to Achieve UN SDGs by Utilization of Forest’s Ecosystem Services”

本号

、

持続可能
者

地域

・

立大学准教授：「SDGs
」 特集
原稿

解説記事
、本

民

結

全国

第 12 期議長、
掲載

。

掲載
、同時

集

：森
概要

、

MNRE（環境天然資源省・生物多様性経済公社）
組

向

、本

国連森林
寄

実現

生態系

生

紹介

、基調講演

・

州

参加

「生態系

BEDO/

支払

(PES)」 取。
開催

2018 in 東京」 報告書

本研究科
収録

後援

行

「第 22 回森林
、併

市

参照

（https://www.moridukuri.jp/wp/wp-content/uploads/2018/09/tsudoi_2018_report_180616_17.pdf）。

1

特集
ソフィアシンポジウム：「SDGs の実現に向けて：森の生態系サービスを生かした持続可能な地域づくり」
Sophia Symposium 2018:"Sustainable Regional Development to Achieve UN SDGs by Utilization of Forest’s Ecosystem Services”

ソフィアシンポジウム：「SDGs の実現に向けて：森の生態系サービスを生かした持続可能な地域づくり」の概要について
Overview of Sophia Symposium 2018: “Sustainable Regional Development to Achieve UN SDGs by
Utilization of Forest’s Ecosystem Services”

柴田晋吾
Shingo Shibata
上智大学大学院地球環境学研究科
構、森林
援

得

市民

生
） 開催
内容

結

、国内外

、上智大学地球環境研究所、国土緑化推進機

全国

集2018 in 東京実行委員会、上智大学国際人材育成

専門家

招平成30年6月17日

持続可能、450 名

地域

越

方々

紹介

、
「SDGs

」

実現

国際

参加

得

向

：森

後
生態系

（

。本稿

、本

概要

主

。

〇プログラム
14:30

受付開始

15:00-15:10

開会挨拶

江馬一弘

15:10-15:40

基調報告 1

Peter Besseau（

上智大学学術研究担当副学長「SDGs・国連森林戦略計画
可能15:40-16:10

地域

基調報告 2
「

実現

進

生

持続可能

）

向

：「生態系

―

Erin Kelly（

・

・

・

」 生
20 年＋

経験

州

―森林

地域

推進」

取引

16:20-17:30）

Peter Besseau（

・

」

）

16:10-16:20 休憩（

持続） 国連森林2

第 12 期議長

生態系

Erin Kelly（

・）州立大学准教授

Rujira Pongpluthong（・）

国天然資源環境省生物多様性

経済公社課長
温井 浩徳

横浜市水道局水源林管理所長

足立 直樹

株式会社

代表取締役

水谷 伸吉 More Trees 事務局長
井原 愛子 MAPLE BASE 代表
（

）

柴田 晋吾

上智大学教授・大学院地球環境学研究科委員長

閉会挨拶

17:30-17:40

・

・

上智学院

化推進担当理事〇シンポジウムとパネルディスカッションのハイライト
・

・

氏

国連森林

国際

、

20 年 +

態系

生

。
政策

20 年近

間

豊富

、

。SDG ｓ

実行

実行
」

取

組

（生態系

国連

関係機関

反面、実行
不可欠

紹介

。

当

必要

） 焦点

、

分析

行

・

様々

打

出

、
指摘
早

進

、世界各
、生態系

、我々

全

価値

。

、「実現可能

価値・利用

利用

同時

満

、全

、地域

」
（Workable Balance） 見出
見出

、

。
。

氏

全

生態系

複雑

価値

、

自然資源

支払

」
（PES）

、他

提供者

絡

合

、多

劣化

止

規制的

政策

博士

、生態系

補完

州

調査結果
比較的容易

持続可能
含

紹介
地球規模

市場

行

同等性

取引

森林

3

仕組
是正

取引

組

比較

、

州
他

事例

目的
焦点

当

、森林所有者

生態系

、森林

。

。「生態系
状況

取
。他

価格

、受益者支払

PES、特

地域

困難

一

、

、

生

計量化

理由

提供
。

扱

政策
問題

」
（inclusive partnership） 鍵
・

、生

、

。実際、Sustainability
「包括的

図
講演

乏

100 ％満足
見出

実現

」

進

「協働型決定」事例

氏、「SDGs・国連森林戦略計画

地域

極

「景観
地

経験

持続可能
、

氏

長年携

生態系

対

、炭素

計測

森林
副次的

便益

・
、

氏

Partnership Building)

実現

系

） 広範

支払
焦点

当

、

基

戦争」 呼
向

後者

、景観美

紹介

巡

激

対立・紛争
組

生物多様性

着目

企業

確認

事例

「森

組

行

中

次第

沈

基

水

興味深

実

散見

着目
、国内外
熱心

参加

数多

現場

質疑応答

貴重

、

、
閉会

議論

紹介

PES、上下流

現場

行

。
取

組

「包括的
実現 「PES（生態系
」 密接

不可欠

組

発生
取

CSR 活動

立脚型
旅

着目

本
表明

取

、

、短時間

構築」(Inclusive Partnership Building)
系

各

西海岸地域

報告
感謝

「PES（生態」 可能性

取引、非木材森林産品

、

行

。

源 PES、森林炭素
地域振興、生物多様性

事例報告

立脚型

敵
。

構築」(Inclusive
博士

中心

行

原生林伐採

報告

最後

、及

・

、

践事例

必要

、

質疑応答
、

「包括的

生態系

提案

前者
静化

何

強調

、多様

関係

生態系

。

4

、
着目

支払

） 広範

我々

Sustainability
SDGs

生態
実現

Sophia Symposium 2018:"Sustainable Regional Development to Achieve UN SDGs by Utilization of Forest’s Ecosystem Services”

Regional approaches to Achieving Global Policy Objectives

Peter Besseau
Abstract
The United Nations Sustainable Development Goals (SDGs), universally adopted by UN member
states in 2015, represent the most ambitious, comprehensive, and urgent policy architecture yet devised
to provide a global blueprint for a sustainable future. Yet, nearly 30 years after the largest gathering ofworld leaders at UNCED, in 1992, and the adoption of the three “Rio Conventions” (Biodiversity, Climate,and Desertification) the world is awash in policy, and sorely deficient in its implementation. Additionally,
our problems have multiplied in number and complexity, demanding integrated, cross-disciplinary, andmulti-partner approaches to their resolution. As the SDGs are now being rolled-out, regional (“localized”)
approaches are being increasingly championed for their ability to mobilize the necessary partnerships, totarget action effectively, and to take on-board the interconnected nature of many of these problems. Regional
approaches to implementation, such as that pioneered by the International Model Forest Network – which
was also launched at the Rio Summit – have a rich accumulation of experience from around the world ofusing inclusive partnerships operating at regional (landscape) scales to achieve important policy objectives.
This experience can shed light on workable, concrete approaches to regional scale implementation of SDGs.
The Model Forest experience and lessons learned over the past nearly thirty years highlights the need not
only for action in our landscapes but transformative processes that ultimately change not only the landscapebut ourselves, our relationships with one another and with our landscapes.

5ソフィアシンポジウム「SDGsの実現に向けて：森の生態系サービスを生かした持続可能な地域づくり」

地球規模の政策目標を達成するための地域的アプローチ
ピーター ベッソー
概要
2015 年
未来

国連

国

向

採択

将来像

政策構築

。

３

作

国連持続可能上、1992 年

最

、

足

状況

解決

野心的、包括的

緊急

世界

集

最大

会議

砂漠化） 後、世界

政策

溢

UNCED

条約（生物多様性、気候、
、実行

。

、多

統合的、分野横断的、

多様

必要

。SDGs

必要

促進

用

景観

関係

複雑性

区域

）

狭

、行動

効率的

数多

目標

可能

達成

世界各地

地域

数

現在、「地域（地理的、、（IMFN） 、
政策目標

問題

開始

実施

踏
」 、重要

発展目標（SDGs） 、持続可能

創始

実施可能

確実

経験

教訓

、景観

究極的

変

経験

相互

。国際

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行動

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蓄積
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支持

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＊

＊）日本語要旨翻訳

6

柴田晋吾

Peter Besseau: Regional Approaches to Achieving Global Policy Objectives

This paper concerns the implementation of policies that support sustainable development at a regional
level and, in that context, about the lessons learned by the International Model Forest Network over the pastnearly three decades in taking just such an approach. These lessons learned are a very timely illustrationof possible approaches to supporting implementation of the very ambitious and equally important United
Nations Sustainable Development Goals (SDG’s). The SDGs were adopted by all UN members in 2015
and represent the global community’s agreed-upon policy architecture through which we are to achieve asustainable future. The paper looks first at this policy architecture and then examines some of the challengesof implemention, particularly at the regional level. Finally, the experiences of the IMFN are drawn upon toillustrate workable approaches to implementing policy at a regional level and key lessons learned from the
IMFN that can be helpful to others seeking to make lasting progress on these critically important policy
objectives. It stresses the importance to the success of a regional approach of marrying transactional workwith transformational process. The observations and analysis provided here are drawn from the author’s
25+ years in international forest policy, including nearly nearly two decades as Executive Director of theInternational Model Forest Network Secretariat, Director of International Affairs for the Canadian Forest
Service, Chair of the Global Partnership on Forest and Landscape Restoration and Chair of the Bureau of
UNFF 12.

Policy Context
Implementation of anything starts with a plan - or policy - setting out objectives and proposed actions
in support of desired outcomes. For the purposes of this paper, a simplified and condensed overview of key
international global policies around sustainable development provides “the plan” in question. It begins withthe 1992 UNCED1 Conference (the Rio Conference) and its three most important outcomes: the United
Nations Framework Convention on Climate Change (UNFCCC); the United Nations Convention on
Biological Diversity (UNCBD); and the United Nations Framework Convention on Desertification (UNFCD).
With agreement on these conventions, the global community of sovereign states, the extended family ofUnited Nations organizations, and a host of other actors, large and small, pledged to prioritize individualand collective actions in these three areas. As the end of the millennium approached, global attention
also turned to the plight of the hundreds of millions of people in developing nations to whom the many
remarkable advancements of the twentieth century had been largely denied. The Millennium Development
Goals (MDGs) (2000 – 2015), therefore, focused on action to alleviate poverty, increase health, education,
job security, and human dignity, among other important goals – along with much higher levels of resource
transfer from developed to developing countries. With the conclusion of the MDGs, in 2015, and with much
1

UNCED: United Nations Conference on Environment and Development

7

remaining to be done, a more ambitious and universal agenda was negotiated and agreed upon – the United
Nations Sustainable Development Goals (SDGs). The SDGs constitute the most comprehensive and, arguably,most ambitious framework yet devised, as indicated in the preamble to the SDG document:
We are resolved to free the human race from the tyranny of poverty and want and to heal andsecure our planet. We are determined to take the bold and transformative steps which are urgently needed
to shift the world on to a sustainable and resilient path.2
The SDGs, to be delivered between 2015 and 2030, comprise 17 goals and 169 targets, addressing acomprehensive package of challenges – social, economic, and environmental – that threaten our earth
and our societies, and include, inter alia, the objectives of the three Rio Conventions, poverty, aquatic andterrestrial ecosystems, sustainable communities, and many others (see Table I). They are described andunderstood to be interconnected and necessarily supported by multi-disciplinary, multi-partner approaches.
While forests and forestry are not specifically cited in all of the 17 SDG goals, a careful reading of them andthe associated targets makes clear that there is an important forest component in each goal and, indeed, aworld with a successfully delivered SDG agenda will be one that will necessarily includes significantly larger,
healthier, and more resilient forest cover.

Figure I

The SDGs are universal – adopted by and applicable to all UN member states – as were the Rio
Conventions 4 – however, rather than being thematic, or issue-based, like the Rio Conventions, the SDGs
are comprehensive, interconnected, time-bound (to 2030) and supported by a more robust infrastructureof integrated action, tracking, reporting and support across the UN system and with collaborating statesand entities. There is also arguably a much greater sense of urgency around them. Unfortunately, thismore robust and urgent approach – while welcome and positive - does not simply represent a more mature,
2

Transforming our World: the 2030 Agenda for Sustainable Development, (preamble) p. 3

3

https://sustainabledevelopment.un.org/sdgs

4

There are two exceptions: the Holy See and the USA did not sign the three Rio Conventions, although thelatter has actively supported activities related to their implementation over the years and has participated informal discussions of them as an observer.

8sophisticated approach to problem solving: in great measure it is the unfortunate result of a significant
accumulation of undelivered policy objectives since 1992 and the arrival of many more vexing problems in
the interim. However one looks at it, it can scarcely be denied that nearly 30 years after the Rio Conventions
were adopted our world, despite being ever richer in policy, is still profoundly deficient in its implementation.
This reality has obligated policy makers to devise a policy architecture to accommodate a much larger setof challenges and an approach to addressing them that recognizes their profound interconnectivity. This
interconnectivity, in turn, has provoked a significant reconsideration of what implementation should look
like, in particular, in a way that recognizes the essential need to implicate many more stakeholders thanhas been the case to date and at a scale (regional) that can produce more reliable and durable outcomes.
More positively, however, and regardless of how circumstances brought us to this cross-road, the SDGs
can be seen as having good potential to bring more effective tools, approaches, and perspectives to our
problems. This is particularly the case concerning opportunities for implementation at regional levels.
The understanding of the SDG package as being interconnected represents an important and largely new
entry point for problem solving that not simply invites but rather insists on cross-disciplinary, multi-party
approaches. This latter approach, often referred to as “localization” - a form of regional implementation- in some of the most recent SDG-related documents5, appears to be gaining traction and does represent
an important departure from past delivery patterns that often resulted in unhelpfully exclusive / narrowapproaches, high opportunity costs, and “turf” issues among potential delivery agents6.
But, before looking more closely at “localization” or other regional approaches, some consideration
should be given to the question as to why implementation has proven to be so very difficult.

Why has Implementation been So Difficult?
In the context of the Rio Conventions and the SDGs, implementation takes place at all levels: for example,
nation states establish benchmarks for carbon emissions and many have developed cap and trade and othersystems to reduce emissions of green-house gasses. They can also establish and support conservation areas,
create incentive systems (taxes, subsidies, and the like) to encourage or discourage behaviour of individuals
or businesses, etc. Depending upon the country (a unitary state, versus a federated union, for example),
specific power to act may be delegated to sub-national units, which will effectively have the lead on policy
and implementation. And, of course, at municipal, community and even individual levels informed policies
and choices can be made around issues ranging from what we eat and otherwise consume to how and what5

http://localizingthesdgs.org/about-us.php

6

The question of why we have substantially not delivered on the Rio Conventions and many other global goals is oneof the most important to have a clear answer to. We need to understand our pathology of inaction because if we do
not understand its nature it is very likely that we will continue down the same road and equally likely that we will be
unable to devise workable solutions.

9we recycle, the use and availability of public transportation, fuel efficient vehicles and so forth, all of which
can positively contribute to our shared objective of a sustainable future. And, while progress has been madein these and other areas, the rate and extent of progress has consistently proven to be deficient, which begs
the question, why?
There are many reasons that are frequently cited to explain the gaping disparity between objectives
and outcomes. Among these, some of the following would be familiar to most people: the need for large,
adequate, and predictable sums of money; the need to know precisely what to do when confronting problems
previously unencountered, managing opposition from entrenched interests; navigating competing priorities;
obtaining or creating suitable and affordable technology; obtaining accessible and understandable sciencebased knowledge to support decision-making; coordination of actions across disciplines, and manyothers. However, and based upon experience of the IMFN, the most intractable barrier to implementation
can be traced to a consistent failure to acknowledge and/or understand the full nature of the change
required. Implementation is much more than a financial, technical, scientific or managerial problem – it isfundamentally a complex social problem. Not only does it entail all and other of the very real and challenging
problems itemized above, which are essentially transactional in nature, but it is more fundamentally about
things that are transformational in nature. That is, it will not be enough for us to do better “things” on ourlandscapes – we have to change ourselves as part of the process, we need to stop some of the things we areaccustomed to doing, unlearn some very bad habits, genuinely accept that there will be costs and trade-offs
that will require us to change how we live – individually and collectively - and, fundamentally, we need totransform our relationship with and understanding of one another and with our world itself.
Both transactional and transformational change are needed, however, it is how transactions are
conducted that can make them transformational – or not - and this is where regional approaches and the
IMFN experience since Rio can shed light on effective ways to deliver more positive outcomes. The IMFN
approach was specifically designed to marry transactional actions to a transformational process, or, more
simply put, it married action to a deliberate idea of partnership within specific landscape settings. What
was observed consistently as the IMFN developed was that this business of stakeholders working together(between government departments, NGOs and the private sector, rivals, adversaries, those who are nottrusted, those who are too free with their opinions, and so on) is probably the most difficult thing that we
can do, which also explains why it has been so thoroughly avoided. For good or ill, however, experiencehas also shown clearly that we do not have a choice – we need to find a way for those conversations to takeplace and for common cause, in some fashion and in some measure, to emerge. This is, not surprisingly, nota project – it is a process. This type of change is a guided process that will require at least a generation or
two and will always be dynamic. However, any journey begins by taking those first steps and this is where10regional approaches offer some very exciting, very concrete opportunities in support of “implementation”.

Why a Regional Approach: Implementing policy at a regional level
The term “regional level” in the context of this paper is meant to be largely interchangeable with closely
related terms such as landscape approach, watershed management, integrated resource management,
ecosystem approach, and many others, all of which have in common an approach that embraces threeelements: a land-base large enough to be inclusive of multiple resource sectors (agriculture, mining,
forestry, recreation, etc), multiple values ( understood as economic, social, environmental, aesthetic, etc.,
and sometimes described in the context of ecosystem services [see Table II, below]), and multiple actors(private sector, government, communities, NGO’s, rural, and urban population centres, etc.). The idea of aregional approach, as reflected by these elements, is to establish a scale for implementation that embraces,to the extent possible, the full range and complexity in which our sustainability challenges actually exist
and partnerships reflective of that range and complexity. So, a landscape or regional scale, for sustainability
purposes, is arguably the most efficient scale to capture all of the elements needed to move forward withtangible, concrete action across a menu of objectives. If the scale is too large it will become difficult to target
actions with sufficient accuracy and difficult to engage stakeholders in that process. If the scale is too small,interesting and beneficial activities can certainly take place, but probably not with the interconnectedness of
issues and actors needed to address multiple issues and opportunities. In terms of physical scale, a relatively
sparsely populated country, such as Canada might work at a watershed scale comprising millions of hectares,
whereas a mountainous, densely populated country, such as Japan, might also consider regional approaches
within a watershed scale, recognizing that mountain watersheds in Japan can consist of fewer than 100,000
hectares. But in both of these examples, the mix of activities, values, and actors would be fully present.
To consider the benefits of a regional approach from another perspective, one can ask the question –when we talk about implementing sustainable development policies, who exactly is to do the implementing?
Ultimately, if it does not engage all of the actors who have interests and impacts on the landscape, if they
are somehow excluded from the process of transforming the landscape, most efforts are likely to struggle
and ultimately develop as stand-alone projects, and/or risk being orphaned. The idea of a regional approachis to work at the right scale, engaging the right partners, and jointly debating, negotiating and selecting
activities that are transformative of our landscapes simultaneously as they transform the institutional andhuman relations on the landscape.

11

Table II: Ecosystem Services7
Supporting

Habitat for Species; Maintenance of genetic diversity

CulturalRecreation and mental and physical health; tourism; Aesthetic appreciation andinspiration for culture, art and design; Spiritual experience and sense of place

Provisioning

Raw materials, fresh water, medicinal resources

Regulating

Local climate air quality; Carbon sequestration and storage; Moderation of extreme
events; Waste-water treatment; Erosion prevention and soil fertility; pollination;
Regulation of water flow; Biological control.

The regional scale, in addition to supporting the types of transactions and transformations describedabove, is extremely important more broadly to the implementation of the SDGs because this scale has proven,in the IMFN experience, to be manageable, represenative, replicable, and, not least important, successful
in delivering results.

The IMFN Experience
The origins of the IMFN date from a period of intense conflict in Canada’s forests, most notably arounda place called Clayoquot Sound, in British Columbia, roughly from the mid-to-late 1980s, until the early
1990s, but certainly also including other resource-based conflicts. At issue in many cases was logging of oldgrowth forests that pitted a traditional partnership of government and industry against a growing allianceof parties representing different, non-industrial values who had no effective entry point into discussions
or decisions about how the landscapes should be managed and for what values. Out of this period of very
heated conflict, occasional mass arrest, and global media coverage there emerged a significant paradigm
shift in resource management in Canada: from a period and a tradition largely dominated by a closed,
economically-driven relationship between government and industry to one which started to become moretransparent, accountable, inclusive and open to and accommodating of multiple values (economic, cultural,conservation, aesthetic, recreational, and so on). 8This general milieu of conflict was also an important sourceof inspiration for the Model Forest program. The strength of opposition to the status quo that emerged in
the late 1980s and early 1990’s in Canada was such that government and industry were essentially left withtwo choices: either continue with business as usual and prepare for endless conflict in the forest or find away to invite other interests and perspectives into the resource management discussion and be preparedfind a way to accommodate them. From this general period of conflict emerged the outline of what became7

http://www.fao.org/ecosystem-services-biodiversity/en/

8This is, of course, a significant over-simplification: these changes represented many years and great effort
to change deeply imbedded habits and beliefs around forest management, creating working relationships
out of mistrust; and, of course, creating a new functional system of interaction, new outcomes, credible
evidence-based decision-making, etc. to name just a few. Indeed, the process of evolution and maturation
continues.

12first, Canada’s Model Forest Program, and ultimately, the International Model Forest Network, which wasformally announced by Canada at the RIO (UNCED9) Conference, in 1992.
The six core principles that constitute the IMFN today are essentially the same as those framed by the
Canadian Forest Service in the early 1990’s:
1. A large, multi-use landscape with an important forest component
2. An inclusive, voluntary partnership.
3. A commitment by those partners to work together toward agreed-upon sustainability objectives
4. A programme of work reflective of the values and interests found in the landscapes
5. A governance structure that is inclusive, accountable, and transparent
6. A commitment to networking and sharing knowledge and know-how
Operating within the parameters of these six principles, partners were to develop their own “model”
of sustainability. And this is perhaps the most important underlying feature of the “model”: the idea that
all landscapes are unique (resource endowment and history of use, population, culture, demands andpressures on the resource base and so on) and that, as a consequence of this, work in support of sustainability
objectives will also necessarily be unique to any given landscape. This has very important consequences tothe objective of implementation. It means, for example, that sustainability – in practice – is necessarily asub-national activity. It means that there is no fixed recipe for sustainability – it will require a customized
approach in each location that it is pursued. It means that sustainability must be a decentralized activity
where responsibility is put into the hands of many people, with very diverse interests. And, because there
is no universal model to follow, work toward sustainability will necessarily be a process of joint learning,
exploration and doing, rather than delivering a project or product for a “client” on a fixed schedule according
to a preordained planning process, as might otherwise typically be the case.
One of the challenges that framers of the model forest concept had was how to get those with tenure andauthority over the land to agree to sit down and work with those without tenure or authority. Those withpower had no incentive and, in fact, could be understood to be wary of potentially having to surrender power
through this process or, at minimum, agreeing to an arduous, time-consuming process that held no advantage
for them. This problem was overcome in the following way: the model forest partnership would be voluntary
and no tenure or authority would be surrendered. However, to compensate for the potential weakness of its
voluntary nature.all partners would agree to engage in an open, transparent, informed discussion about how
they understood the land, its problems and ways to manage toward sustainable outcomes. Further, those withtenure and authority over the land (government, industry, private sector, farmers, for example) – who would
also share their views - would agree to consider for testing, adoption, or adaptation new ways of conducting
9

United Nations Conference on Environment and Development

13

their affair as proposed by the broader partnership if a persuasive case were made. Through this process of
discussion, exploration, action and negotiation, these diverse, non-traditional partnerships created the space
to better understand one another and the legitimacy of the various perspectives and values that each held,
the potential benefits of doing do things differently, and the commonalities between them that were, to thatpoint, largely unknown and unexplored. These partnerships were often very stressful and difficult to form
and manage, however, in most instances the need or desire to deal with shared problems in a new way, usuallycombined with a) appropriate support and encouragement from policy level, b) leadership of key, respected
figures, and c) resources to initiate action, was enough to bring the partners together and focus attention on ashared package of issues. This approach to partnership, governance, and action represents the transformational
aspect of the model forest – a structure that demanded an investment from stakeholders in the form of theirtime, good faith, attention, and willingness to learn new things, and that provided the time and opportunity
for them to take ownership of the process and take it forward according to their values, interests and objectives.
These are very early days for rolling-out “localization” for the SDGs, but if one looks at some of therecent descriptions of “localization” for their delivery, such as the one from UNDP, below, one can see
striking similarities with what the IMFN has been doing and, as such, excellent opportunities for learningand up-scaling such experiences in greater support of the SDGs:

Localizing development means taking into account subnational contexts in the achievement of the2030 Agenda, from the setting of goals and targets, to determining the means of implementation and using
indicators to measure and monitor progress. It is also putting the territories and their peoples’ priorities,
needs and resources at the centre of sustainable development. There should be sustained exchanges between
the global, national and local facets.
In the past, localization was mainly meant as the implementation of goals at the local level, by sub-national
actors, in particular by local and regional governments. But this concept has evolved. All of the SDGs havetargets directly related to the responsibilities of local and regional governments. That’s why the achievement of
the SDGs depends, more than ever, on the ability of local and regional governments to promote integrated,
inclusive and sustainable territorial development.
Subnational governments are policy makers, catalysts of change and the level of government best placed
to link the global goals with local communities. Localizing development is then a process to empower all local
stakeholders, aimed at making sustainable development more responsive, and therefore, relevant to local
needs and aspirations. Development goals can be reached only if local actors fully participate, not only in theimplementation, but also in the agenda-setting and monitoring.
Participation requires that public policies are not imposed from the top, but that the whole policy chain
is shared. All relevant actors must be involved in the decision-making process, through consultative and14

participative mechanisms, at the local and national levels. 10

Today, the IMFN continues to use its a regional / landscape approach to deliver on a broad range ofpolicy objectives, linked to the SDGs, across its six geographic networks (Canada, Ibero-America, Baltic,
Mediterranean, Asia, and Africa), with a total of nearly 70 sites across more than 30 countries, encompassing
almost 100 million hectares. The model has been as enthusiastically taken up in developed as in developing
countries, in tropical and boreal ecosystems, in areas of dense human population and areas of relatively
sparse population and wilderness. Notably, most Model Forests that have been created continue to operate
and this despite the fact that most do not have secure, core funding from their host governments11. Indeed,
the ongoing strength of model forests in developing countries – without core support – is a remarkableindicator of the significant value of the model to partners in those landscapes.

Over many years of discussion with Model Forest practitioners around the world there have been asmall number of recurring explanations accounting for the longevity of the network’s sites: the first is thegovernance system and specifically the fact that it is inclusive of all voices and interests, respectful andforward looking. Moreover, invariably over time, partners in the Model Forest process come to see thesepartnerships as being not optional but rather essential to achieving their goals. The second most frequently
cited advantage of the model forest model is economic: virtually all Model Forests include activities tosupport sustainable economic outcomes for their partners. The third most important value associated with

Figure Ⅱ10

http://localizingthesdgs.org/about-us.php

11

An informal calculation indicates that as many as 18 Model Forests have ceased operation for various reasons
over the years (i.e. key work had been completed; partnership failure; lack of financing, and other reasons).

15

the model forests is the practical nature of the work undertaken – sustainability for these partnerships
is not an abstract, academic, or distant aim, but one that is tangible, relevant and achievable. Finally, thenetwork itself is seen as a major asset to partners as it represents a community of practice and learning that
can accelerate progress. As indicated in the examples cited below of individual model forest activities andaccomplishments, while there are some thematic similarities in the activities (economic, restoration, tourism,etc.) of some model forests they are unique to their setting and to the values of their individual partnerships.

Selected Model Forest Accomplishments:
All model forests have broad-based programmes of work, and within them, flagship activities that are ofcentral importance to the partnership. To cite just a small number of cases, here are some of the main areasof activity and accomplishment of selected Model Forests.
In Canada, the Eastern Ontario Model Forest, in place since 1991, has become an accredited organization
for forest certification under the Forest Stewardship Council. This has allowed it to support thousands ofindividual woodlot owners who would not otherwise have been able to afford FSC certification.
In Morocco’s Ifrane Model Forest, partners there have focused on combating desertification and addressing
poverty and sustainable economic development based upon their natural resource sector.
On the densely populated island of Puerto Rico, the Tierras Adjuntas Model Forest, partners, including theisland government, were successful in developing and having passed a Model Forest Law which legislated
measures to reduce forest fragmentation (increase forest corridors) and increase biodiversity.
In France (Provence, Alpes, Cotes d’Azure Model Forest), multiple regional governments banded together
to better support sustainable rural agriculture and strengthen the role of wood and non-wood products in
the regional economy, in part, to reduce rural out-migration.
In northern Europe, Sweden’s Vilhelmina Model Forest saw partners work to reconcile traditional reindeer
herding across northern landscapes with the interests of private land owners.
In Cameroon’s Campo Ma’an Model Forest its main objectives were to diversity the agricultural andresource-based economies, improve agricultural productivity and incomes, and establish agricultural
production chains, all of which would reduce poverty while taking pressure off of the forest resource.
In the Philippines’ Carood Waterhsed Model Forest, a partnership led by 7 municipalities, 13 peoples
organizations and multiple other partners are working on major projects to restore a significantly degraded16ecosystem, including rehabilitation of steep slopes and mangrove forests, reintroduction of native species,
improved irrigation systems, nature-based tourism, livelihood development based upon local capacities,
interests and resources and many other areas.
In Japan’s Kyoto Prefecture Model Forest, a model unique to the IMFN saw the creation of a network of
public and private forests that draws heavily on prefectural corporations to provide leadership, together
with volunteer citizen groups to address climate, forest, water and related policy objectives, support healthy
engagement of citizens in nature and conservation, and reinforce the strong historical and cultural ties
between the people and nature of Kyoto Prefecure.
Finally, by way of example, the Chorotega Model Forest, in Costa Rica, built on and expanded an initiativeof local farmers and leaders in a watershed that had been severely degraded (88% of forest cover removed,
severe degradation of water quantity and quality, resulting in significant population decline as young people
and families left the watershed). Through their actions they were able to acquire degraded land, restore forest
cover, including with native and commercial species, strengthen the local economy, improve water supply
and quality and halt out-migration.
Each of the activities itemized above represents only part of a broader program of work in the respectivemodel forests and also represent concrete actions for implementation of one or several of the SDGs, national
policies and the priorities of regional partners. But the most important thing to note on the above is thateach of these activities is being shaped, selected, and delivered by individual regionally-based partnerships
based upon the model forest construct: the IMFN framework provides the form while the partnership
determines the content.

Lessons learned:
If regional/landscape approaches are indeed now seen as among the most highly recommended
approaches to achieving the SDGs (including closely related approaches, such as localized,
watershed, ecosystem-based, a nd ot hers) t hen what lessons does t he IMFN ex perience
have that might help others successfully put in place such constructs? In addition to several
observations already made, some of our most helpful lessons would include the following:1.

Although noted above, it bears repeating here: Recognize that each landscape and its
approach to implementation is necessarily unique: Regional or landscape approaches bydefinition mean that the specific approach, the priorities and the partnership that shapes
them will be unique to that landscape. As such, while implementation can be guided(frameworks such as the IMFN, tools, etc.) it cannot be imposed from outside and it cannot
be prescriptive. Implementation is ultimately cross-sectoral, multi-actor, and unique to its

17setting. Implementation therefore requires tailored approaches to fit each unique landscape.
2.

Establish priorities: No regional initiative can possibly address all 17 SDG goals and all 169 targets
simultaneously. Priorities and choices need to be made based upon open dialogue, sound science,landscape values and interests, and technical considerations, as well as clear relevance to policy.

3.

Doing, Not Doing, and Un-doing: Implementation is as much about doing what needs to be done,
as it is about not doing, or stopping activities that are harmful or counter-productive, and unlearning and un-doing the things that created our problems. In Model Forest experience, this very
important evolution in learning and critical thinking begins with the formation of the partnershipand development of the critical listening and learning skills that are key to moving forward.

4.

Ensure the Partnership is Inclusive: Create a partnership as complex as the values and uses of thelandscape and a forum where open and respectful dialogue on difficult issues can take place. It is notuncommon that different departments within the same government, and different levels of government
do not work together and are even adversarial to one another. Equally, indigenous people, local
communities, and the poor are often overlooked as potential partners. These groups have important
contributions to make and must also be beneficiaries of efforts to achieve sustainable outcomes.

5.

Link to policy and policy-makers: Make the work relevant, and known, to higherlevel policy makers and to local groups and interests. Ideally, the partnership will want
to include policy-level actors as a member of the partnership. This not only allows apartnership to broadcast its relevance, but it also provides opportunities for up-scaling
and replication and may also provide an important source of support and financing.

6.

Clearly identify benefits: Most, if not all partners, will want to participate in a regional
initiative because they have a stake in outcomes that ref lect their interests. These“stakeholders” will remain part of the initiative so long as benefits – even those thatare long-term – are well articulated in ways that are clear and meaningful to themand when the path to realizing them is clearly set forth and effectively communicated.

7.

Understand that healthy partnerships are dynamic, life-like things: Partnerships need to be
nurtured, supported, recognized, celebrated and guided. Trust can be difficult to establish.
Over time, interest can wane, particularly as complex and/or longer-range objectives are
slow to materialize. Because of this, strategies and approaches should be devised to build
trust, and to sustain, nourish and invigorate the partnership, including ensuring that shortterm milestones, outcomes and successes are clearly identified, achieved and celebrated.

18

8.

All partners should be considered equal, but that does not mean that they are the same:Some partners will have little or no experience working, negotiating, collaborating or evenpromoting and defending their own interests. It is important to be patient with and support
less experienced partners who need time to learn how to engage in the process. Indeed, it isin the best interest of the partnership that all are able to effectively participate. At the otherend of the spectrum, partners who are experienced and who are accustomed to leading
and directing often have a difficult time listening, following others, and being open tolearning. This too is vital to a healthy partnership and takes time to evolve and mature.

9.

Give it time: sustainability is a process - not a project. Learning and adapting is a permanentfeature of sustainablity across all landscapes. Additionally, these partnerships willalmost always draw together historical adversaries, those who have no previous working
relationship, and there will be an absence of trust among many. Partnerships take time andspecific action in order for trust to emerge. Without that trust, the partnership will not last.

10.

There are no shortcuts and it will be difficult: Recognize that achieving desired outcomes will bedifficult but recognize equally that there are no shortcuts – we have to work with one another toachieve these outcomes, and this includes working with those we are unaccustomed to working
with, and those we frequently choose or prefer not to work with.

11.

Regional approaches and the partnerships that support them are not self-financing:
Predictable, adequate core funding is essential. While funding is absolutely necessary.
too much can cause more problems than it solves: Having too much money for an initiative
can attract “fair weather friends”, those who are quite happy to join the partnership andhelp spend its money on projects and activities of their liking, only to leave the partnershipwhen funds are spent. The impact of such partners can be toxic to a partnership andneeds to be managed carefully and in the overall interest of agreed-upon outcomes.

12.

Cultivate and encourage ownership: Sustainability, as an actively pursued goal, must be “owned”
by the people who will win or lose based upon what is done. Put the challenge of sustainability into
as many hands as possible. Make it part of people’s lives. Let them own it, guide it, benefit fromit, worry over it. Who else but communities, and multiple other interests in a given landscape are
best placed to sort out the actual trade-offs, synergies, benefits and losses? This includes partners
ranging from government and industry to landless peasants and every interest in between.

13

Link with like-minded practitioners and initiatives outside of your region: The workof sustainability is difficult and frequently under-appreciated, with the rewards often
slow to materialize. Also, because the work is, by its nature, very focused on local
19

circumstances, it can be also somewhat isolating. We have found that there is greatstrength in linking with the broader global community of practice that is working with
regional approaches. Linking with that community provides confirmation that theirpartnership approach is valid, reassurance that their efforts are worth the investment,rich learning opportunities, and much needed encouragement to continue this work.
14.

Recognize the fundamentally social nature of what we are doing: Achieving global goals insupport of sustainable development is definitely about restoring and conserving our environment,
about striking a balance between what we take from the environment, what we leave untouched,what we rehabilitate, and so on. It is also about funding, policies and projects. But successful
implementation will ultimately depend less upon projects and more about a change in culture,
meaning that sustainability, ultimately, is not about changing our landscapes – although it requires
this – it is about changing ourselves, our relationship with our landscapes and with one another,and it is about understanding the impacts and trade-offs of our resource management and use andconsciously modifying our actions in order to have a better chance of achieving a balance between
what we need to live sustainably and what the landscapes need to remain healthy, dynamic, andproductive.

20

Sophia Symposium 2018:"Sustainable Regional Development to Achieve UN SDGs by Utilization of Forest’s Ecosystem Services”

MOTIVATIONS FOR CREATING FOREST OFFSET PROJECTS: EVIDENCE OFENVIRONMENTAL AND SOCIAL CO-BENEFITS UNDER THE CALIFORNIA CAP-ANDTRADE CARBON MARKET

Erin Clover Kelly*, Marissa Bongiovanni Schmitz** and Ariel Weisgrau***
Abstract:
Forest carbon offset projects, one type of payment for ecosystem services (PES), have been successfully
developed under the California cap-and-trade program. As with many PES markets, forest offset project
development and implementation has potentially created co-benefits, or benefits in addition to carbon
sequestration. Through interviews with market participants, we assessed motivations for developing forest
offset projects, and linked these motivations to co-benefits. We found that landowners and managers joined
the market to diversify revenue, generate revenue from restricted lands and non-harvest (conservation)
activities, generate revenue when other (timber) values were diminished, implement a patient investment
strategy on cutover or degraded lands, and/or demonstrate the viability of forest offset projects under acap-and-trade market. Using these motivations as a starting point, we hypothesize the potential creation of
ecological (e.g., preventing fragmentation) and social (e.g., rural job creation) co-benefits under the market.
These co-benefits extend beyond the explicit purposes of the market and thus our paper offers a starting
point for thinking about the wide range of ecological and social co-benefits that are possible with forest
carbon offset markets.

*

Humboldt State University**

University of Minnesota***

Humboldt State University

21

ソフィアシンポジウム「SDGsの実現に向けて：森の生態系サービスを生かした持続可能な地域づくり」

森林カーボンオフセットプロジェクトの動機：
カリフォルニア・カーボンオフセット市場における環境社会的コ・ベニフィットの実証

エリン クロバー ケリー・マリサ ボンジョバンニ シュミッツ・
アリール ワイスグロー
要旨「生態系

支払 （PES）」 一形態、
多

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成功裡
同様

、森林

、炭素固定以外
行
多角化
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構築

便益
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行

、制限

上

。
土地

、伐採地

市場

分析

結果、土地所有者
保全活動

荒廃地

忍耐強

森林

可能性

得

、
市場

） 社会的

。

・

（地域

雇用創出

） 創設

可能性

検討

広範

生態的

、本稿
社会的

、

防止

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提供

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知見

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森林
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22

低下

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分

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上回

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目的

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出発点
直接的

・

参加

実行

動機
市場

動機

、他 （木材

投資戦略、。市場参加者

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実施

可能性

、森林

結

。

」

州
。他

入

「森林

足

柴田晋吾）

MOTIVATIONS FOR CREATING FOREST OFFSET PROJECTS: EVIDENCE OFENVIRONMENTAL AND SOCIAL CO-BENEFITS UNDER THE CALIFORNIA CAP-ANDTRADE CARBON MARKET

1 Introduction
Payments for Ecosystem Services (PES) are voluntary transactions that seek to ensure provision of
ecosystem services such as carbon sequestration or watershed protection (Wunder 2005). PES markets arestill emerging and their potential for providing social, economic, and ecological benefits are uncertain.
PES markets have the potential to create co-benefits, which are environmental and social benefits notdirectly related to the particular good being traded in the PES market, resulting in greater environmental
sustainability and social equity (Bulte et al. 2008). These co-benefits are positive externalities: that is, they
benefit third parties who are not directly involved in the PES market, including the general public. PES
operates under the assumption that environmental conservation of an ecosystem service can be encouraged
by privatizing and assigning ownership, thus “internalizing” a previously externalized cost (Robertson 2007).
Forest offset projects under the California cap-and-trade carbon market (“forest offset projects”) are one
type of PES in which forest landowners enter all or part of their forests into the market to offset emissionsof carbon-polluting entities. This paper is an exploratory, preliminary assessment of potential co-benefits
under the forest offset market based on interviews. We evaluate whether (and which) environmental andsocial co-benefits are potentially being created based on who is entering the forest offset market, and theirmotivations for entering the market. Some environmental co-benefits are built into the market, namely underthe “Natural Forest Management” requirements for projects, which have certain biodiversity and forest standstructure requirements, as well as a 100-year permanence (or maintenance of carbon) requirement. Other
co-benefits are not required, but are incentivized by protocol design, including provisions that encourage
third-party certification and/or the existence of a forest management plan. Our paper focuses on otherco-benefits that depend on discretionary choices. We explore these choices as they relate to participants’broader goals and objectives for managing forestland, as well as their motivations for entering California’s
carbon market.
The California cap-and-trade (or “compliance”) market has created a much higher price for forest offsets
than previous (voluntary) markets, which means that a large number of landowners may be motivated todevelop forest offset projects. Proposed motivations for joining the market include diversification of revenue
sources (Caldwell et al. 2014), doing the “right thing” in terms of climate change mitigation (Markowski et al.
2011), or alignment between carbon market objectives and existing landowner objectives (e.g., conservation)(Ruseva et al. 2017). But most studies have used hypothetical samples of landowners and asked whether
landowners would join the market under different conditions; the current research focuses on landowners
and project developers actually in the market, and asks why they joined. Part of the purpose of this research
was to assess the potential co-benefits from the market.

23

Before the establishment of forest offset projects under the California cap-and-trade market, someobservers speculated that carbon markets would produce co-benefits—including biodiversity andmaintenance of marginal forest lands (Wayburn et al. 2000). But biodiversity and carbon sequestration
are not mutually assured. Phelps et al. (2012) outlined five different ways to approach the dual objectives of
biodiversity and carbon sequestration under different assumptions: 1. Prioritizing seamless win-win carbon
sequestration and biodiversity protection, assuming that such opportunities exist; 2. Separating carbon
sequestration and biodiversity protection entirely and approaching them as two separate policies; 3. Adding
on biodiversity conservation as part of carbon market policies through voluntary and incentive programs;
4. Adding on biodiversity conservation through payments for “co-benefit optimization”; and 5. Making
biodiversity conservation central to carbon markets, potentially creating large costs and high barriers
to entry. These five policy approaches highlight that biodiversity does not necessarily just emerge fromcarbon markets, but depends on policy design, site, and other factors. Beyond biodiversity co-benefits, mostsocial scientists are concerned with social co-benefits, including equity and livelihood concerns (VisserenHamakers et al. 2012). Similar to ecological co-benefits, these social co-benefits do not arise automaticallyfrom carbon markets, but may be incorporated into market design or may be excluded or seen as tangential
to the market functioning.
The aim of this paper is not to justify the legitimacy of PES markets as we recognize that many PES
markets, including forest offsets, simplify and commodify complex ecosystems and social relations (Corbera2012). But we wish to offer some initial lessons from California’s forest offset program in the context ofglobal attempts to create forest offset programs, such as under the United Nations Reducing Emissions
from Deforestation and Forest Degradation (REDD+). As these schemes are developed, they can look to
the experiences of California’s program, and some may also wish to integrate with California’s market. In
this paper, we address two questions: what are motivations for joining the carbon offset market, and what
can these motivations teach us about potential co-benefits? We build on previous work by Anderson et al.
(2017) who reviewed project design documents for forest offset projects in the California compliance market
and coded them for co-benefits, including mention of watershed improvement or habitat for threatenedor endangered species. This paper asks similar questions, but we assume that motivations for entering themarket can offer important insight that might not be available in project design documents, which are often
written by third party developers and which serve a specific purpose, i.e. successfully passing registrationand verification procedural requirements.

1.2 Background: California’s cap-and-trade market and the role of forest offset projects
California has largely forged its own path on climate policy after the US left international climate change
agreements, first exiting the Kyoto Agreement in 2001 and then the Paris Accord in 2017. In 2001, thestate established the California Climate Action Registry to record carbon emissions and establish baseline
conditions; this state-run agency eventually became a non-profit organization that registers offset projects
in the cap-and-trade market. In 2006, Assembly Bill 32 (AB32) passed in California, which set standards
for carbon emissions reduction for the state: to 1990 levels by 2020, and a further 80% by 2050. One tool of24

AB 32 was the proposed cap-and-trade market, which was launched in 2013 after years of protocol design
and baseline carbon emissions measurements. Under the cap-and-trade market, offset projects (including
forestry but also agriculture, landfill, and other projects) are purchased by “capped” (carbon-polluting)entities to offset their emissions. Offsets provide some flexibility for capped entities to offset their emissions,
supplementing allowances (purchased from the state or other capped entities) and investments in carbonreducing technology.
Cap-and-trade markets are not new in the United States; they are seen as more politically palatable thanregulatory (simple cap) or tax approaches because they give businesses more flexibility to find greenhousegas reduction strategies. Several regional partnerships were established in the early 2000s to create carbon
markets (the Regional Greenhouse Gas Initiative with ten states, the Western Climate Initiative with sevenstates and four Canadian provinces, and the Midwestern Greenhouse Gas Reduction Accord, with six statesand one Canadian province) (Rabe 2016). Many of the states and provinces withdrew from these regional
partnerships, though RGGI has remained intact. As of 2018, while RGGI has continued, California’s market
has developed along a different path, with a more complex and comprehensive market, and with higher
regulatory hurdles than other markets (Bang et al. 2017). This is in part because of the exceptional natureof California as a state: it has an unusual political context, with much stronger environmental laws and amore competent administrative branch than most other jurisdictions, creating the conditions necessary fora successful cap-and-trade market (Bang et al. 2017).
Under California’s market, offsets can only be used to offset 8% of an entity’s emissions, and forest
offsets are only one type of offset. Therefore, we are focusing on a relatively small part of the cap-and-trade
market. Despite being a small part of the cap-and-trade market, forest offsets are complex and can becontentious because of the difficulty of ensuring that they are “real” – that is, they are sequestering carbon
and contributing to the overall objective of reducing emissions of greenhouse gases.
Forest offset projects in California’s market may be developed in any state in the US, but generally
only forests that are not owned by the federal government. There are three types of forest offset projects:
reforestation, avoided conversion, and improved forest management. Within the market, improved forest
management (IFM) projects are the most common type of project, and are the focus of this paper. The
IFM protocols are complex, but there are three components that are central to understanding project
development: 1. Permanence, 2. Verification, and 3. Additionality. To achieve permanence, forest offset
projects must be maintained for 100 years past the last date of carbon sale. Verification requires that qualified
third-party actors verify that projects are, indeed, sequestering the promised amount of carbon.
Additionality is central to the functioning of forest offsets; it is a concept that seeks to differentiate
between background or “typical” carbon sequestration that takes place in absence of any forest offset project,
and additional carbon sequestration that results from participation in the carbon markets. Before forest
offset projects enter the market, developers conduct in-depth inventories of carbon stocking, and theseinventories are compared to nearby similar forests as measured under the nationwide Forest Inventory andAnalysis (FIA) program, which is maintained by the US Forest Service. This allows for national participation
because FIA is a standardized, nationwide dataset. Carbon stocking standards are established based on these25FIA data among forests similar in terms of species and geographic context, creating a “common practice”
for the region, which constitutes the foundation of the baseline for forest offset projects.1 If proposed forest
offset projects are above common practice, then they are able to generate immediate revenue, which is
calculated as the difference between the carbon stocking on the project and the carbon stocking of common
practice. If proposed offset projects are below common practice, they must wait to generate revenue, until
the projects exceed common practice.

2 Methods
Initial in-person interviews (n=25) were conducted with both project developers and protocol designers
focused on the development of the forest offset protocols, who participated in their design, and how thedesign changed over time. Through the process of interviewing and coding, we discovered common
motivations for projects to enter the market, and began to theorize project typologies based on how entrants
were leveraging their market participation, and in some cases, how carbon revenue was utilized. We thenlooked for patterns in our database of projects that could confirm, undermine, or expand upon thesehypothesized motivations and strategies.

Table 1. Interviewee types by landowner, developer type, geography, and plans to harvest timber.
Landowner types: NIPF = non-industrial private forest (i.e., “family” forest owners), TIMO = Timberland
Investment Management Organization.
Landowner types

Developer types

Conservation

16

In-house

16

NIPF

6

12

Industry

8

Consultant
Contract(professional
carbondeveloper)

Geography (USFS region)
Southwest
23(California)
Northeast
7

7Southeast

2

TIMO
Miscellaneous
TOTAL

2
3
35

Northwest

3

35

Harvesting timber?
Yes

21

No

14

35

35

We followed this with additional interviews (n=21) with project developers and/or landowners—i.e.
people identified as responsible for forest offset project development. These twenty-one people represented
thirty-five projects that differed by landowner type, developer type, geography, and whether the projects
involved harvesting timber (Table 1). The sample was not representative of all the projects in the market

1

Other baseline components can include legal and economic considerations (e.g., conservation easements)
but for the purposes of this paper, “common practice” is equated with baseline.

26

(Figures 1 and 2) but offered a wide range of project types. Fifteen interviews were conducted by phone;
six were in-person. In our initial outreach emails, we offered a list of potential motivations and asked
interviewees to identify the motivations that best fit their projects. This list changed over time as more
options were added during discussions. Therefore, while we find the interviews to be illustrative of strategies
and motivations to enter the market, we caution that we cannot generalize quantitatively.
We also compiled a database of IFM projects using publicly-available records from two registries: theClimate Action Reserve and American Carbon Registry. We classified landowners into types based on landownership and read all publicly-available documents regarding project design. We included a total of 158
listed projects (updated in the summer of 2017), including all projects that had filed preliminary paperwork
to enter the market, some of which had already been awarded offset credits. We utilized this database toassess total market participation (Figures 1 and 2) and to calculate the number of projects below common
practice.

Number of forest oﬀset projects in the California cap- and trad e market by ownership type
40
35
30
25
20
15
10
5
0
T I MOI nd ustrial

Conserva on

NI PF

T ribalMiscellaneous

Unknown

Figure 1. Forest offset projects in the overall market, by ownership type.

Number of forest oﬀset projects by US Forest Service region
70
60
50
40
30
20
10
0
PaciﬁcSouthwest(California)

Northeast

Southeast

Southwestern

PaciﬁcNorthwest

AlaskaRocky
Mountain

Figure 2. Forest offset projects in the overall market, by region.

27

3 Results: Motivations for joining the market
Through initial interviews and subsequent follow-up interviews with project developers, we developed
a template of motivations for landowners and project developers to enter forests into the offset market(Table 2). Many interviewees identified multiple motivations, or variations on suggested motivations. The
list of motivations changed as a result of interviewee input, and therefore numbers across interviews are
not comparable. We found that the list served as a starting point for discussions about why projects werebeing enrolled.

Table 2. Identified motivations for landowners and project developers to develop forest offset projects
under the California cap-and-trade market.
Motivations
Revenue Diversification: Management objectives include diversification of forest revenue. Forest offsets, wood
products, and conservation easement dollars may be utilized together for economic and forest management objectives.
Conservation focus: Timber harvesting is economic and feasible, but is secondary to conservation objectives orcontrary to objectives. Carbon is attractive as a non-extractive revenue alternative.
Highest and Best Use (HBU): The most valuable use of the land and timber is in the carbon market, whether because
mills are distant, market value for timber species is low, or because grading makes harvest infeasible.
Restricted Lands: Projects have regulatory restrictions or easements existing on the property before project
development, limiting timber income opportunities.
Patient Growth: Project stocking is below, at, or moderately above Common Practice; projects patiently wait for carbon
to grow and accumulate.
Demonstration of market viability: Projects are used to test and demonstrate the feasibility of carbon-offset projects inthe market. May fit with participantsʼ objectives and values or may be in response to trying to meet conventions to
reduce carbon footprint or protect the environment.

3.1 Revenue diversification
By far the most common motivation identified by interviewees was revenue diversification. This was
described as managing forests for a range of financial benefits alongside forest offset revenues, including
wood products and/or other conservation funding such as from easements. In interviews, twenty-one
projects were identified as involving “revenue diversification” as a motivation. Of those, fourteen projects
were actively managing for timber and seven were not.
This category, which often placed forest offset revenue alongside timber harvest, highlights thatmanaging for carbon means different things for different landowners and project managers. It includes
everything from no-harvest preservation-style projects to traditional production forestry. Most interviewees
who were harvesting timber indicated they had not changed their silviculture or harvesting behavior, because
the carbon market was complementary to harvesting or to their previous management objectives. Several
interviewees did indicate they had changed their harvesting behavior: three said they harvested less because28

of a forest offset project, and one said they harvested more—because prior to the carbon market, they had
not considered harvest, but in bringing in consultants for the project, they became interested in harvesting
as a restoration tool.
One reason for revenue diversification was cyclical returns within the timber market – that is, thefluctuating prices of timber. In the words of one project developer, “Before the [carbon] market, money
was made from timber harvests. There was lots of pressure from the [timber] market to harvest more
intensely and more frequently… it’s hard for owners to manage for the long term, but the [carbon] market
is complementary with sustainable forestry. The [carbon] market was a counter to the traditional model.”Not all projects were diversifying income from timber production; for example, one project, located inan agricultural area, used their carbon revenue to diversify multiple revenue streams, including recreation,leased land, Christmas trees, and orchards.

3.2 Conservation focus
For some projects, interviewees indicated that carbon revenue fit conservation objectives related toreduced harvesting. In the words of one interviewee, the strategy was to monetize ecosystem services tosupplement revenue and “take the pressure off harvesting.” In this sense, the revenue from having a forest
offset project allowed other (conservation) objectives to be achieved, and sometimes filled important funding
gaps, when other revenue opportunities became scarce. As one interviewee stated, “I think a lot of land trusts
are starting to realize that there is value in the property that we have, and we have a head start because weown the land. Let’s make it work for us and enhance it at the same time. Not be begging at the troughs ofgovernment agencies for grants. Because frankly those monies have dried-up.”
A number of conservation ownership interviewees pointed to the need for carbon income because ofloans acquired during land purchase. As one indicated, the carbon market helped to “bridge a fundinggap” that existed; others said that carbon market revenues went directly to loan repayment. In fact, one
interviewee pointed to carbon revenues as a way to gain funding for further land acquisitions: “We’reconsidering using carbon offsets on an acquisition project… as a portion of the funds to pay for theacquisition…it will be one of the legs of a three legged stool: one will be carbon offset proceeds, another will
be grant funding, and the other will just be donors in the area. A three legged approach to buy the property.”
There were a small number of projects that interviewees indicated could engage in timber harvesting,but they elected not to altogether. We termed this sub-category of the conservation focus as “non-extractive”
in terms of motivations. In one interviewee’s words, they were “focused on conservation, not forestry” andtheir motivation was to protect a watershed. While none of these projects were actively harvesting timber
for commercial purposes, most interviewees who identified “non-extractive” motivations did remove trees
for other purposes, such as habitat, wildfire risk reduction, or restoration.

3.3 Highest and Best Use
Interviewees said that some projects demonstrated that carbon was the “Highest and Best Use” (HBU)of the forest, and pointed to a lack of timber markets (e.g., because of distant mills or low species value) or29

infeasible harvests (e.g., because of steep slopes). Another reason identified was stumpage prices – whenstumpage prices are low, carbon may become the HBU because the opportunity costs are less. A total of nineprojects identified carbon as HBU, and five of these did not engage in timber harvest, but four did, indicatingthat while timber harvests are marginal for some HBU projects, they are still possible.
One interviewee indicated that their forest property was in its fifth generation of family ownership. They
watched as timber markets changed and mills closed in their region, eventually resulting in carbon as thebest economical use of their land. As with many landowners and managers who indicated that carbon was
the HBU, they supplemented carbon revenues with other sources of income.

3.4 Restricted lands
In contrast to HBU projects, some interviewees noted that they worked on projects wherein timber
harvest was restricted not by markets but by legal restrictions, either existing conservation easements or
because the lands were in a designated protected status. One interviewee indicated that their project wasdeveloped on property which had been designated a recreation area and set aside for the carbon market,
while timber harvests continued elsewhere on the ownership. Another interviewee suggested that they
developed projects in already-restricted riparian set-asides. This suggests the possibility that landowners
can carve-off pieces of larger ownerships, enrolling only those in the carbon market that have little or notimber harvest.
One interviewee indicated that he thought that developing a forest offset project “makes more senseon encumbered land than unencumbered land” because “by selling a carbon encumbrance you’re already
restricting the land.” He explained that landowners and project developers could essentially layer on
encumbrances, netting revenue through different conservation sources.

3.5 Patient growth
Patient growth was described as a motivation by only a few interviewees, though we view it as potentiallyvery important for the market. Projects can be established on cutover, degraded lands with low stocking
that may have low purchase price, and very patient investors can then wait to produce credits (and income)under the carbon market. Two projects in the database were established on very low-stocked lands, which
an interviewee said would not generate timber returns for “ten to fifteen years.” Under this scenario, if alandowner has sufficient patience (and revenue flows elsewhere), they can enroll their project in a market
which will eventually produce returns.
Our database confirmed the possibility of this “patient growth” strategy, as thirteen projects were listed
below Common Practice standards. Of these, six projects had conservation landowners, which may indicate
the willingness of conservation landowners to purchase and rehabilitate degraded timberlands.

3.6 Demonstration of market viability
This category was created after several early interviewees identified demonstration of market viability as
an important motivation for entering the market. Two separate interviewees labeled themselves as “guinea

30

pigs” for the market, explaining that their forest offset projects were intended to demonstrate that the market
could work. One interviewee who had developed industrial projects specifically noted that they wanted todemonstrate the viability of industrial projects within the market, and to demonstrate the feasibility of“stewardship management” within the timber industry, using the market as a tool.
In the words of one interviewee, they wanted to demonstrate market viability because the market“places a value on the forest as a forest,” rather than as a commodity producer. A number of interviewees
also indicated that they wanted to demonstrate viability in order to contribute to a lower carbon footprint,
or “move the needle” on climate change and emissions. This demonstration of market viability extended
to providing lessons for other project developers in order to teach them how to enter the market, as one
interviewee stated: “we wanted to model this and prove the concept so that people could see how it worked
and hopefully learn from, that it would help in the adoption and participation by others.”
This identified motivation to enter the market in order to demonstrate viability speaks to skepticism thatthe sale of forest offsets could actually function as a marketplace, providing real revenue to participants, aswell as to the difficulty of getting forest offset projects into the protocols at all. Most cap-and-trade markets
have not included forest projects because of concerns related to the uncertainties of forest management,
particularly unintended reversals (e.g., insect infestations and wildfires), leakage (e.g., harvesting more
intensely outside the project area to compensate for reduced harvests within the project area), and the
difficulties of precisely capturing carbon sequestration through field measurements.

4 Discussion: Potential co-benefits
Under the framework suggested by Phelps et al. (2012), there are multiple ways that carbon markets can
incorporate co-benefits. In the California market, some co-benefits (e.g., preference for native species and a
100-year permanence requirement) are built into market protocols. Another co-benefit created through thedevelopment of the market itself has been the creation of new jobs in forestry, such as carbon consultants,
inventory specialists, growth and yield modelers, carbon financiers and aggregators, project auditors, andmarket registry staff (Kelly and Schmitz 2016). This is because ecosystem markets are expert-dependent,
creating high demand for human capital with understanding of the technical and complex aspects ofquantifying ecosystem services within forests. New professional opportunities within forestry may beespecially important in a context of declining timber markets, and a need to re-establish the relevancy offorestry as a profession through changing consumer demands and social values.
But other co-benefit production depends on choices made by market participants. These choices arereflective of participants’ wider goals and objectives for managing forestland, as well as their motivations
for entering California’s carbon market. Anderson et al. (2017) reported on a range of ecological co-benefits
on forest offset projects in the California carbon market, based on voluntary reporting in project design
documents. Their research provides an important snapshot of ecological co-benefits, particularly as they
relate to program requirements. Our results based on interviews suggest broader-level co-benefits that areboth ecological and social, and which extend beyond program requirements. We now outline some of theseco-benefits (Table 3) and discuss implications for policy-makers, particularly as they relate to understanding

31

the full ecological and social implications of using forest carbon markets as tools for climate mitigation.
Table 3. Potential social and ecological co-benefits generated by the forest offset market, based onlandowner motivations.
Potential co-benefit:

Motivation:
Revenue
Diversification:

Maintaining forest
lands as forest lands= Economic benefits
for rural places(particularly jobs),
reduction offragmentation

Creating
opportunities forconservation finance/
revenue sources =more conservation
capacity

Reducing pressure toharvest timber =longer rotations,older forests, lessharvest in
ecologically sensitive
areas

Creating social
license = corporatesocial responsibility,

x

x

x

x

x

x

x

Conservation focus:
Highest and BestUse:

x

Restricted Lands:
Patient Growth:xxx

Demonstration ofmarket viability:

x

x

x

x

x

4.1 Maintaining forest land as forest land
The ability of forest offset programs to help maintain forest land as forest land, i.e. to reduce forest
fragmentation, is one of the most likely co-benefits of forest offset projects under the California market. Thisis important because maintaining forest cover creates a range of ecosystems services, including productionof wildlife habitat and watershed improvement, as well as quality-of-life benefits, such as recreation, viewshed, and maintenance of open spaces (Millennium Ecosystem Assessment 2005). Maintaining forest landalso contributes to rural economic co-benefits, including contributions to remaining timber economies,
and to the sustainability of rural places and ways of life.
Because of the exceptionally long permanence requirement built into the California protocols, all lands
entered into the carbon market have a measure of insurance that lands will stay forested; forest offset
projects can be canceled, but only with repayment of revenue earned, plus a penalty if canceled within thefirst fifty years. However, we found that by offering another source of revenue, carbon offsets can especiallyhelp maintain forest cover for economically marginal properties by defraying the costs of owning andmaintaining forestland and/or by improving the economic appeal of forest management in the face ofcompelling land-use alternatives. Economically marginal properties include those owned by landowners
who might otherwise sell forest land into real estate or other purposes, such as family forest-owners (Hatcher
and Greene 2013), as well as particular forest types, such as those in regions that have lost timber processing
capacity and infrastructure, or because they have been previously harvested or do not contain economically32

viable species.

4.2 Increasing opportunities for conservation finance
Increased opportunities for conservation finance is an important co-benefit of offset projects in the
California market. In part because forest offsets provide non-extractive revenue, with reduced pressure
to harvest timber, there are increasing opportunities for conservation landowners (e.g., land trusts),
tribes, family forest owners, and other landowners with multiple objectives. Specifically we found thatcarbon-revenue provided two types of benefits for conservation-minded landowners: funding for new landacquisition, and revenue that can be used for ongoing stewardship and restoration, such as management
to reduce invasive species and/or to restore older forest conditions. This is in part because forest offsets
typically provide an initial lump sum of revenue, which can be used for property acquisition, followed bysmaller but consistent payments for new forest growth, which can fund restoration and/or contribute to
debt service on acquisition loans.
One interesting finding was that the existence of the California forest offset market improved somelandowners’ access to public and/or private loans for property acquisition, and in some cases, developmentof forest offset projects became a stipulation to receive funding. For conservation NGOs in particular,
offset revenue fills a gap left by diminished public grant monies for conservation generally; and, because
carbon revenue is ongoing, it has the added potential to provide funds for stewardship on properties thatconservation landowners are increasingly tasked with managing long-term. The availability of non-extractive
revenue also opened opportunities for conservation NGOs to participate in commercial forestry markets,
which was not always available with traditional timber markets, because offset revenue was viewed as moresocially acceptable to the community and/or in closer harmony with organization goals. A unique benefit
of increased conservation finance that applies to tribes includes greater capacity for these landowners to
re-acquire customary homelands, which we found to be the case on several projects.

4.3 Reducing pressure to harvest due to non-extractive revenue potential
Due to offset revenue, landowners and land managers who have enrolled forests in the California
program may have reduced pressure to harvest trees. This can offset over-harvesting for landowners who
prefer or require a steady forest income (for example, if they harvest at low market prices), or for landowners
who need an influx of income. The carbon market alleviates over-harvesting under these circumstances
because there is not a need to harvest to maintain revenue; rather, landowners may balance timber harvest
with sale of carbon credits, in order to better facilitate forest regrowth or other ecological objectives, or tomore strategically time timber harvest sales, e.g. by extending rotation ages/cutting cycles if stumpage prices
are low, and instead selling carbon, until timber markets rebound.
At a broader level, the introduction of a legitimate revenue stream not based on timber extraction has
the potential to facilitate a transition already underway within US forestry towards management for multiple
objectives (McQuillan 1993). Forestry is a service-oriented profession that seeks to meet the evolving goals
and objectives of society (Hull 2011), but within the confines of existing market opportunities. Timber

33

extraction and creation of wood products has long been the sole reliable income stream for most forest
types—with exceptions for certain properties with unusual conservation or recreation value—and theprimary driver of management decisions. The possibility of carbon revenue can thus increase the rangeof management options open to landowners, for instance by allowing practitioners to engage in moreexperimentation with management and/or to employ strategies that might align with management goals
and objectives, but which require a basic level of revenue generation. This could include extending harvest
rotations to produce higher quality wood products, reducing harvest in ecologically sensitive areas such as
wetlands or within stream buffer zones, and/or reducing erosion as roads are used less often and vegetationis allowed to remain on site for longer periods. Sale of forestry offsets may also allow for use of smaller
harvest units, resulting in reduced clear-cut sizes and more options for less-intensive silvicultural methods,
e.g. single-tree and group selection, rather than even-aged methods.
We note, however, that managing for timber does not preclude co-benefit production; it facilitates someco-benefits (such as restoration and fire management), and contributes to rural livelihood and community
resilience. Combining timber and carbon fits with forestry that aims to achieve multiple benefits.

4.4 Creating social license
An interesting finding of this research is that forest offset market participation has the ability to create
or improve social license among timber companies. This is important because of declining public approval
for commercial timber harvest in the US during the environmental movement of the last half century, withcritiques focused on degrading logging practices, harvest of iconic old growth trees, and destruction of
habitat for threatened and endangered species (Salwasser 1990). Public disapproval led to lawsuits against
timber companies and direct action by environmentalists aimed at halting logging (Widick 2009), andfacilitated policy changes that increased the stringency and oversight of forestry regulation. Forestry practices
have evolved since this period of high controversy, but negative public perceptions remain, particularlyin certain regions of the US, such as the Pacific Northwest. Carbon market entry represents one way tolend environmental credibility to timber companies, by improving their image as prudent land stewards
with long-term commitments to sustainability. Specific benefits of greater social license include: improved
public relations with communities and with regulatory bodies, fewer environmental-legal challenges,
more autonomy with forest management decision making, and improved market value of forest products.
Many timber companies, including for instance Timberland Investment Management Organizations, arepairing carbon market entry with other markers of environmental stewardship, including participation incertification schemes, such as the Sustainable Forestry Initiative (SFI), and sale of conservation easements.

4.5 Equity: A missing co-benefit
Thus far we have highlighted numerous co-benefits provided by or open to forestry offset market
entrants. However there were a number of ways that the market was missing anticipated co-benefits, the mostglaring of which is a lack of equity within the market in terms of landowner participation. This is because
only relatively large acreages or those with high carbon stocking can join the market (Kerchner and Keeton342015). This means that many of the most economically marginal landowners, particularly non-industrial(family) forest landowners are unlikely to join the market, whether because of high barriers to entry (highcosts), or lack of capacity or desire for a 100-year commitment (Kelly et al. 2017). This is reflected in therelatively small proportion of NIPF landowners in the market. While the California market may not besuitable for NIPF landowners, this means that they do not fully benefit from this new revenue source, andmany of their forest lands remain vulnerable to fragmentation. Meanwhile, landowners who may be mosteconomically comfortable and have the most options (e.g., timber industry) have a new source of revenue.
This raises important questions about the additionality and co-benefit potential of forest offset projects
owned by large timber producers. One concern is that, if carbon market participation fits seamlessly into
the regulatory requirements of commercial timber producers, these projects may not offer substantial
greenhouse gas reduction or other co-benefits. However, Anderson et al. (2017) find just the opposite,
concluding that conservation landowners are “non-additional” while industrial projects are “additional,”
based on assumptions that timber companies actually need to alter their management to enter the carbon
market. These questions deserve further research that can consider nuance and complexity, and which
acknowledges that no landowner demographic is monolithic. Our research highlighted above, however,suggests that carbon-based revenue is likely to create co-benefits even for large timber producers who maypractice business-as-usual forestry, insomuch as it increases the viability and competitiveness of US timbercompanies in the face of wood product market declines and global competition, which have led to forestry
mill closures and loss of capacity since the 1990s.

Conclusions
This paper offers a starting-point for thinking about the range of ecological and social co-benefits
that are possible on forest offset projects. Some co-benefits, such as improved watershed quality or habitat
improvement, are likely to be shared by all participants, by virtue of policy requirements or because of themany ecosystem services inherently produced by forests, but other co-benefits will vary project-by-project
and by region and will be influenced by landowner motivations for market participation, as well as bylandowner goals and objectives for forest management more broadly. Future research comparing differencesamong geographic regions and landowner types can improve our understanding of forest offset co-benefit
potential. In addition, comparative research that investigates co-benefit production across multiple carbon
offset programs may illuminate the factors that influence the types and magnitude of co-benefits that are
possible with forest offset projects.
Many of the lessons of the California market are not transferable to other places. For example, land
tenure is well-established in the United States relative to many places where competing land claims, often
between the state and indigenous people, remain unresolved. But the motivations for project development
and related co-benefit production still offer insights for policy makers considering forest offsets as tools forclimate mitigation. In particular: this research may help policy-makers evaluate competing offset options—e.g., dairy methane digestion, rice methane capture, or rangeland soil carbon sequestration—by stimulating

35

discussions on the wide range of longer-term social and ecological implications of alternative land-based
greenhouse gas reduction options. In a context of concerns about whether offsets provide ‘real’ climate
mitigation (Lohmann 2009), research on ecological and social co-benefits can also provide policy makers
with a fuller picture of the direct and indirect outcomes that are possible from forest offset programs,
regardless of whether they provide ton-for-ton carbon sequestration exchanges.

References
Anderson, C.M., C.B. Field, and K.J. Mach. 2017. “Forest offsets partner climate-change mitigation withconservation.” Frontiers in Ecology and Environment 15(7): 359-365.
Bang, G., D.G. Victor, and S. Andresen. “California’s cap-and-trade system: Diffusion and lessons.” Global
Environmental Politics 17(3): 12-30.
Caldwell, B.T., K.A. Holland, Z. Barbane, and M. Jonas. 2014. “AB 32 – a compliance carbon market for US
forests, an opportunity for foresters.” Journal of Forestry 112(1): 60-61.
Corbera, E. 2012. “Problematizing REDD+ as an experiment in payments for ecosystem services.” Current
Opinion in Environmental Sustainability 4(6): 612-619.
Hatcher, J., T. Straka, and J. Greene. 2013. “The size of forest holding/parcelization problem in forestry: A
literature review.” Resources 2(2): 39-57.
Hull, R. B. 2011. “Forestry’s conundrum: high value, low relevance.” Journal of Forestry 109(1): 50-56.
Kelly, E.C., and M.B. Schmitz. 2016. “Forest offsets and the California compliance market: bringing an abstract
ecosystem good to market.” Geoforum 75: 99-109.
Kelly, E.C., G.J. Gold, and J. Di Tommaso. 2017. “The willingness of non-industrial private forest owners to enter
California’s carbon offset market.” Environmental Management 60: 882-895.
Kerchner, C.D., and W.S. Keeton. 2015. “California’s regulatory forest carbon market: viability for northeast
landowners.” Forest Policy and Economics 50: 70-81.
Lohmann, Larry. 2009. Neoliberalism and the Calculable World: The Rise of Carbon Trading. In Upsetting theOffset: the Political Economy of Carbon Markets. Edited by Steffen Boehm and Siddhartha Dobhi, 25-40.
London: Mayfly Books.
McQuillan, A. G. (1993). Cabbages and Kings: The Ethics and Aesthetics of” New Forestry”. Environmental
Values, 191-221.
Millennium Ecosystem Assessment. 2005. Ecosystem and human well-being: general synthesis. Washington,
DC: World Resources Institute.
Markowski-Lindsay, M., T. Stevens, D.B. Kittredge, B.J. Butler, P. Catanzaro, and B.J. Dickinson. 2011. “Barriers
to Massachusetts forest landowner participation in carbon markets.” Ecological Economics 71: 180-190.
Phelps, J., E.L. Webb, and W.M. Adams. 2012. “Biodiversity co-benefits of policies to reduce forest-carbon
emissions.” Nature Climate Change 2: 497-503.
Robertson, M. 2007. “Discovering price in all the wrong places: the work of commodity definition and priceunder neoliberal environmental policy.” Antipode 39(3): 500-526.
Ruseva, T., E. Marland, C. Szymanski, J. Hoyle, G. Marland, and T. Kowalczyk. 2017. “Additionality andpermanence standards in California’s forest offset protocol: a review of project and program level
implications.” Journal of Environmental Management 198(1): 277-288.

36

Salwasser, H. 1990. “Gaining perspective: forestry for the future.” Journal of Forestry 88(11): 32-38.
Schmitz, M.B., and E.C. Kelly. 2016. “Ecosystem service commodification: lessons from California.” Global
Environmental Politics 16(4): 90-110.
Visseren-Hamakers, I.J., C. McDermott, M.J. Vijge, B. Cashore. 2012. “Trade-offs, co-benefits, and safeguards:
current debates on the breadth of REDD+.” Current Opinion in Environmental Sustainability 4(6): 646-653.
Widick, R. 2009. Trouble in the forest: California’s redwood timber wars. Minneapolis, MN: University of
Minnesota Press.

37

ソフィアシンポジウム「SDGsの実現に向けて：森の生態系サービスを生かした持続可能な地域づくり」「生態系サービスへの支払い」（PES）により持続可能な地域づくりを目指す―タイにおける取り組みから

柴田

晋吾

概要
国家経済社会開発計画 「生態系支払 （PES）」 位置付

然資源環境省生物多様性経済公社（BEDO/MONRE） PES
様性

高

複数

生態系

進

。本稿

郡）、

Mae Sa 流域（
成果

課題
型

提供

PES

有

紹介

郡） ３
。

考

、持続可能

、地域
発展

促

仲介者

箇所

新

PES

取

組

郡）、Khlong Prasong 准地域（
事例

取

、生物多

各地

Tung Jao 上流地域（

見

、天

組

評価
、Aerni

社会的
期待

時期尚早

、
云

Engel and Wunscher
形成

契機

。

Sophia Symposium 2018:"Sustainable Regional Development to Achieve UN SDGs by Utilization of Forest’s Ecosystem Services”

Pursuing Sustainable Regional Development Through"Payment for Ecosystem Services" PES)
-Implementation Status in Thailand
Shingo Shibata
Abstract
In Thailand, "Payment for Ecosystem Services" (PES) is incorporated in the National Economic Social
Development Plan, and PES activities are conducted to target areas of high biodiversity and multiple
ecosystem services by Biodiversity-Based Economy Development Office/Ministry of Natural Resources
and Environment. In this article, implementation status is overviewed for the upper stream of Tung Jao
Watershed (Chiang Mai Province), Khlong Prasong Sub-District (Kurabi Province) and Mae Sa Watershed(Chiang Mai Province). Although it is too early to evaluate these activities, some positive outcomes andchallenges can be observed. These PES activities can be categorized as hybrid-type defined by Aerni, Engeland Wunscher, etc., and they are expected to help to promote sustainable development through fostering
new social network and business opportunities in the region.

39

「生態系サービスへの支払い」（PES）により持続可能な地域づくりを目指す―タイにおける取り組みから

1．はじめに
貧困、食料不安、政治的不安定などの問題が絡み合っていることが多い開発途上国においても、
UNCED 以降は農業環境政策を強化し、農業の環境への影響を低減させるための環境法が各国で制定され、ドーナーによって、様々な「生態系サービスへの支払い」（Payment for Ecosystem Services,
以下 PES と称する）スキームが行われるようになった。食料安全、生物多様性、水源、文化などの農業のプラスの外部経済に着目した欧州型の資産形成タイプのものから、野生生物保護、森林保全、生物多様性などの農業以外の環境への負の外部経済を低減させるアメリカ型の利用制限タ
イプのものまで様々な形態で行われるようになった [Aerni. 2016]。
タイでは、2010 年に名古屋で開催された CBD、COP10 などを受けて、2012-2016 年の第 11 期
国家経済社会開発計画、および 2017-2021 年の第 12 期国家経済社会開発計画に PES が位置付けられた。第 12 期国家経済社会開発計画には、「PES の考え方は、地域の天然資源の保全を行う地
域コミュニティが追加的な収入を生む生物多様性に根ざした経済開発のもう一つの方法である」と記された。これを受けて、タイ国内各地で国際ドーナーや NPO、および政府機関によって
PES プロジェクトの取り組みが実施されている。とりわけ、天然資源環境省生物多様性経済公社（BEDO/MONRE）はタイ国内での主要な PES の実施機関となっており、BEDO が自ら PES スキー
ムの仲介者となって、生物多様性が高く、複数の生態系サービスを有している箇所をターゲットとして各地で取り組みを進めている。特に、タイ北部においては、BEDO は同じく天然資源環境省の国立公園局（DNP）や郡の水局（Provincial Waterworks Authority, PWA）などと協定を結んで連携しつつ PES に取り組んできている。
BEDO の PES の取り組みは、①対象区域の同定と生態系サービスの評価、②販売可能な生態系サービス、販売予定者、購入予定者の見極め、③ PES の原則の策定と問題点の解決、④交渉と合意の実行、の 4 段階に分けて実施されている [Pongplutong et.al. 2015]。本稿においては、BEDOの主要な取り組み地域である 1）Tung Jao 上流地域（チェンマイ郡）、2）Khlong Prasong 准地域（クラビ郡）、および USAID LEAF の支援を受けている 3）Mae Sa 流域（チェンマイ郡）の事例、の3 つの事例についての取り組みの概要を見ることとする。

2．取り組み事例
1）Tung Jao 上流地域（チェンマイ郡）
郡、Mae Taeng 地域、Pa Pae 准地域、Tung Jao 流域
PES

実施

生態系

少数民族
地

存在

族

評価
集落

準備活動

開始

選

。Baan Hua Lo

実施区域

、豊

水

利用

棚田

、森林

耕地

明確

分

住居

、2012 年

広。集落民

。Tong Jao 流域

40。

結果、Baan Hua Lo
山々

森林
川

水源地域

注

間

依存

平

土

生活
。Tong Jao

業

18

村落

族

680 人、

族

従事

、28 ％

435 世帯

、一家族
PES

存在

、総人口

平均貯金額

販売者
水道水

人
過

Baan Hua Lo

人々

。PWA

生産

使用

内訳

族
。1557

746

雇用労働者

33

Authority, PWA）
給

5 人、

、

5489人

。年間

族

3078人、

世帯

68 ％

平均世帯収入980人、1058 世帯

農

1000

。
、 購入者

Mea Tang 准流域

水水局（Provincial Waterworks
非処理水

国

北部地域

供

。

具体的には、2013-2017 年に、PWA が上流の販売者を雇用し、6 つのチェックダムの建設と維持管理、40 キロメートルの防火帯の設置と山火事防止のための森林巡視を行うという内容で、これらの活動に年間 17 万タイバーツ（5230 ドル）が費やされた。これに対して 75 名の Baan Hua
Lo の人々が参加した。参加した人々はチェックダムの建設に年間 1500 バーツ（41 ドル）の支払いを受け、平均で人々の年収の約 9％の増加が図られた。

図1

Tung Jao upstream watershed, Pa Pae sub-district,
Mae Taeng district, Chiang Mai province of Thailand [BEDO. 2016]

また、2014-2016 年には、PWA が 2 万バーツの予算で 10 名の集落民を雇用して植樹と植栽木の手入れを行った。また、チェックダムの維持管理、防火帯の設置、山火事防止のための森林巡視もあわせてこれらの人々の仕事となった。この結果、一人当たり年間 2000 バーツの追加収入となっ2016 年 8 月に PWA の担当者と会い、たが、これは人々の年収の 12％に相当する額であった。著者は、また現地の集落を訪れる機会があったが、集落の人々と BEDO や PWA などの関係者との強い信頼が生まれているということが、現地での関係者との会話を通じて感じ取ることができた。

41

写真 1

タイ・チェンマイ郡、Hua Lo 集落の景観。棚田と森林の間に清流が流れるカレン族の暮らす山あいの村（2016 年 8 月撮影）。

写真2 同。Hua Lo集落のカレン族の人々。Ms Pongplutong（BEDO/MONRE）（2016年8月撮影）。

本 PES

住民

現在
、持続可能

保全

関係者

結

本 PES

強

実行

成果

Werachai and Pree-ravee[2018]、1）PWA

取

組

多

、2）

保全

学
形成

強

挙

、3）PWA

集落。

2）Khlong Prasong 准地域（クラビ郡）の事例
マングローブ地域の減少はタイも例外ではない。タイでは、1961 年に 3678900 ヘクタールのマングローブが存在していたとされるが、経済開発、インフラ開発、ツーリズムなどによる開発のため、2007 年のランドサットによる調査では 229619 ヘクタールと 3 割以上の減少が起こって42きているとされている。本プロジェクトの対象とされているクラビ郡においても同様な状況である。クラブ郡、Muang 地域、Khlong Prasong 准地域には、沿岸デルタ地域にマングローブが広がっているがエビ養殖の放棄地などによる喪失箇所が虫食い状に存在している。

図2

Krabi 周辺のマップ。沿岸部のマングローブの消失の状況が明瞭にわかる [BEDO. 2016]

BEDO は、美しいマングローブの景観によって恩恵を受けているホテル（Island Eco village resort）、ボート（Khao Kha Nab エコツーリズム）、オートバイ、レストランなどなどを購入者として組織化し、地元の保全組織（マングローブ森林保全協会）を販売者として、マングローブの修復活動を行う PES スキームを 2012 年に開始した。購入者グループがマングローブの修復のための PES 基金を設立し、購入者グループは毎月 15.38 ドルを支払いという契約を締結した。Pongplutong[2018] によればその後の支払いは順調に行われていない状況にあるため、ホテルの宿泊客も巻き込む仕組みも含めた何らかの改善策が必要な状況となっている。

写真3 タイ・クラビ郡デルタ地域には、かつてのエビ養殖跡地の荒廃地が多く存在している（2016年8月撮影）
。

43

写真 4

タイ・クラビ郡デルタ地域の外れにあるホテルでは、
近年沿岸部の木々の根が高波による浸食を受けている（2016 年 8 月撮影）。

3）Mae Sa 流域の事例（Aura-PES）
本地域は、1977 年にユネスコ Mae Sa-Kog Ma バイオスフィアリザーブに指定され、人々と自然、生態系、自然資源をステークホルダーの参加によって持続可能な取扱いを目指している地域である。Mae Sa 流域はチェンマイ郡の Mae Rim 地域に位置し、チャオプラヤ川の 8 つの支流のうち最大であるピン川流域に注いでいる。流域面積は 13,880 ヘクタールあり、チェンマイ市の北西
18-43 キロメートルに位置している。上流部の平均傾斜は 14-54％であるが、下流域になると 0.64％と緩やかになっている。農業、ツーリズム、水企業、産業などの取水によって水量は変動が大きくなっている。
流域

約三分

二（4 ％） 経済林
産地（9 ％）
22

。森林以外
市場目的

村落
下流

森林地域

住

常緑熱帯降雨林
8.63 ％

23.75 ％

中心

従事

。森林減少

森林
及

農業

減少

小流域

、流域

（57.8 ％） 保全林

利用

。流域

村

。

上流

高地

住

、平均

6.67

大
提供

、3436

果樹園（39 ％）、商品農業（38 ％）、花生、
集約的人（76.6 ％）43 ％（1309 世帯） 農業
均

箇所

農業

村落

20

、50140

問題
生態系

。

44

20 村落
少数民族
所有
、1997 年
低下

招

住

4

准地域
3046 世帯、中流

族（23.4 ％）。

。Mae Sa 流域

森林2006 年

間

。森林減少

平

図 3 Mae Sa Watershed と集落の状況 [ 出典：LEAF. 2016]

Mae Sa 流域においては、USAID LEAF プロジェクトの一環として国営企業（Tipco 食品。ミネ
ラルウオーター AURA を販売、唯一の購入者）と Phongkhrai コミュニティ（販売者）が参加して PES スキームに取り組まれている。Pongkhrai コミュニティは Mae Sa 流域の 22 の村落のうちの一つであり、Pongkhrai 准流域の唯一のコミュニティによる Phongkhrai 准流域における 10 ライ（rai）の再植林が主要な活動である。2 年間で 1 ライあたりの樹木密度を 500 本以上とするた
めに、1660 本の土着樹種のほかに 3340 本の苗木が植栽された。総費用は 20 万バーツ（2 万バー
ツ / ヘクタール、40 バーツ / 苗木）となっている。015 年 6 月以降、二年間の間、購入者から 20万バーツが直接コミュニティに対して支払いが行われた。2015 年 6 月からモニタリングと実行の仲介を行うために Aura-PES 調整委員会が設置されている。

写真 5

USAID の支援による水源 PES を実施している Tepco（AURA）国営企業。

45

写真 6

AURA-PES の販売者である Pongkhrai コミュニティでの聞き取り調査の状況（2017 年 8 月）

3．現在までの取り組みの評価
BEDO の PES の取り組みは 2012 年から開始されたばかりであり、実施内容やスケールは限定的・小規模であること、また、Aura-PES も極めて最近開始されたものであるため、これらのスキー
ムの影響を総括するには未だ時期早尚であるが、Pongplutong[2018] は現在までの取り組みについて以下のように評価している。
① 環境管理経済手法 適用

変化

見

彼
変

③ 地域

自然資源 環境

制御 権利

従来

積極的

自然資源管理

参画

環境管理

従来

統合的

行

、Pongplutong[2018]

周

PES

考

② PES
購入者

④ 金銭取引

⑥ 土地

購入意思

。
。

組

、以下

諸点

実行上困難

必要

。
複雑

。

不十分

。

。

必要

、産物

権利関係

不十分

各種資源

供給者

、PES
以上

知識

不確実

交渉技術

⑦
挙

方

行

能力

考 方

。

①

⑤

取

2012年以降現在

点

③ 潜在的

積極的

。

民間

④ 自然資源

態度

。

② 地域
積極的

、

、

供給者

開発、

。

提案書 作成、費用 試算。
実行

法的、経済的

動機

。

。
困難

経験

、 今後

PES

46

実施

必要

点

挙

Pongplutong[2018]

以下

①

PES
。

以下
考

PES

方

二点

考

方

点

含

。
知識

技術

訓練

必要

。

実行

実務的

知識

収集方法
生態系

見極

産物

開発
提案書

価値評価
作成

費用試算
交渉技術
②

PES
、中央政府

実施
PES

動機

動機

作

Environmental Measures for Environment） 制定
。
PES

実行

法的

、地方政府

環境管理

分権

動機 与

不足

問題

必要。環境目的環境手段法（Act on
、PES

経済的手法

法定化

法律規制

制定

、地方政府

。

4．おわりにAerni[2016] は、ネオクラシカル厚生経済学に基づく Coasean タイプの PES 理論を古典的なPES とし、古典的な PES は地域における改革や事業性を無視していたと指摘し、それに代わるハ
イブリッド型の PES が増加してきていること、そしてこのタイプの PES が持続可能な地域づくりにとって大きな役割を果たすことを指摘している。Aerni はハイブリッド型の PES について明
確な定義は行っていないが、従来の厳密な PES の理論に縛られないもので、上下流連携、公・民パー
トナーシップの醸成などによって PES が地域の新たな社会的ネットワークやビジネスの契機を提供し、地域の持続可能な発展につながるものを指してこのように称している。ハイブリッド型
PES では、農民に対しての補償は行うが、革命的な地域の起業などに対してよりオープンなものとなり、彼らの収入を増やそうという意思が生態系サービスを増やそうという公的な利害と一致し、財政的持続可能性につなげることができるとしている。一方、Engel and Wunscher[2015] は、
PES スキームをその性格と購入者などによって、①受益者支払い型（Coasean タイプ）、②政府支払い型（Pigouvian タイプ）、③ハイブリッド型にタイプ区分している。ハイブリッド型は、市
民社会組織、国際機関、政府などの第三者が一定の役割を果たしているものであり、多くの PES
プログラムがこのタイプに含まれるとし、第三者の果たす役割は、所有権の明確化、取引費用の削減、ただ乗りや不完全な情報の克服など多岐に及んでいるとされる。この Engel and Wunscher.
[2015] のハイブリッド型の PES は、第三者の仲介者の存在など構成の複雑性に着目した定義であるが、これらはいずれも Wunder[2005] の定義による古典的な完全型の PES ではなく、公・民パー
トナーシップなどが強調されているなどの点において、実質的には Aerni[2016] の云うハイブリッ
ド型の PES とほぼ類似のグループを指す概念であると考えられる。

47

上記で見たタイにおいて実施されている PES も政府系機関である BEDO が仲介機関となって、地域のステークホルダーが購入者、販売者などの一定の役割を果たすなかで、地域の社会的ネッ
トワークやビジネスの契機を提供することで地域の持続的な発展に資することを目指しているものであることから、Aerni[2016] や Engel and Wunscher[2015] の云うハイブリッド型の PES であるということができるであろう。今後、中央政府レベルにおける PES の法制化の動きも見込まれるところ、今後の動向に注目したい。
注） 本内容

一部

果

。

、上智大学

事業：「河川域」

学融合型国際共同研究

成参考文献-Aerni Philipp. 2016. CSR, Sustainability, Ethics & Governance. The Sustainable Provision of Environmental Services.
From Regulation to Innovation. Springer.
-Engel S. and Wunscher T. 2015. Payment for ecosystem services as a mechanism to promote biodiversity conservation ina green economy. Potentials and limitations. Biodiversity in the Green Economy. Routledge.
-Pongplutong R. et.al.2015. Watershed Management through Payment for Ecosystem Serive in Tung Jao Upstream Areaof Chiang Mai Province, Thailand. Unpublished Paper-Pongplutong R. et. al. 2015. Conservation of Mangrove Forest Ecosystem through Payment for Ecosystem Service: Case
Study of Khlong Prasong Sub-district, Muang District, Krabi Province, Thailand. Unpublished Paper- Pongplutong R. 2018. Verbal communication.
- Usaid Leaf Thailand report PAYMENT FOR ECOSYSTEM SERVICES IN THE MAE SA WATERSHED-Werachai N. and Prae-ravee K. 2018. Payments for Ecosystem Services, and Sustainable Development: The Case ofThailand. Presented at Regional PES Dialogue, Bagkok, Thailand. Aug. 2, 2018.
-Wunder S.（2005）Payments for Environmental Services: Some Nuts and Bolts. CIFOR Occasional Paper No.

48

福島第一原発建屋内のたまり水の放射性汚染状況の解析（5）
大坪

国順

概要
本稿

、福島第一原発建屋内

水

放射性汚染

。東京電力
状

報告資料

（1）原子炉冷却

伴整理

約 110 万 m
状態
（2）

汚染水

3

。

水中
止

新

処理

順調

進

約 86 %、、2018 年内感

。特100 m /day 程度

処理

現

転

放射性物質

見込

薄

、事故当時

除去

。

比

100 分

1 程度

、2018 年 7 月以降
主高温焼却炉建屋
対策

貯留

全

上昇

約 1/2

要因

、建屋

上昇
流入

、主建屋（原子力建屋
建屋。

。現在、一時貯蔵100 %

放射線強度上昇

貯蔵以下、初期放射線強度、

放射線強度上昇

137

上昇

絞

汚染水

水

判明

放射線強度

。両者

3

明

除

比率

、2016 年 10 月以降

懸念材料

策

一年間

137

低減

状況

原子炉建屋内

結果、

放射性汚染水2018 年 10 月末

地下水量

建屋）以外

移送

講

、新

考

貯

。

、

対

。

（3）塩素

濃度

2016 年 12 月
感

、変動
上昇

転

。2016 年 1 月以降
放射線強度

変動

2016 年 11 月

、2018 年 8 月

700 ppm

200 ppm
記録

上下変動

、基本的

同様

。

49

、

下

後上昇
137

。
止

Analysis of time variations of radioactive substances in the ponding water in the mainbuildings of the Fukushima Daiichi Nuclear Power Plant (5)Kuninori Otsubo
Abstract
This paper shows the latest results of time variations of radio-active substances in the ponding water inthe main buildings of the Fukushima Daiichi Nuclear Power Plant. It has passed almost one year from theprevious publishing of my paper on this issue. During the period, the weekly data of cesium 137, tritium, andchloride ion of the ponding water have been kept reported by Tokyo Electric Power Co. Ltd. Time variationsof the three parameters have shown the following tendencies.
(1) At present, about 1,100,000 m3 of the contaminated water has been reserved in the tanks and allradioactive substances except for tritium have been removed from 86% of the reserved water.
(2) The strengths of radiation of cesium137 and tritium have been decreasing to one-hundredth of theinitial strengths up to October, 2016, then, they turned to increase and kept increasing until now.
Especially the degree of increase of tritium has been remarkable. The causes of those increases
are considered that the daily amount of groundwater flowing into the main buildings has been
decreasing to 100 m3 from 400 m3 and some amount of highly contaminated water ponding inother buildings has been transported to the pond in the main buildings. As for cesium137, acountermeasure has been undertaken; however, as for tritium, there was no effective countermeasurefor the increase.
(3) The concentration of chloride ion decreased to 200 ppm momentary and began to increase as ofMarch, 2017 and kept increasing up to now. As of February, 2016, time variation pattern of chloride
ion concentration has been similar to those of the strengths of radiation of cesium137 and tritium
except for the period of between October, 2016 and March, 2017.

50

福島第一原発建屋内のたまり水の放射性汚染状況の解析（5）はじめに2011 年 3 月 11 日

既

7 年半

染水

2018 年 10 月末

同

研究報告

水

放射線汚染強度
追跡

状況

明

濃度

一年
一方

放出
確

考察内容

整理

考察

本稿

検討

使

炉建屋内

地下

存在

関
変更

加

前報

水（

水

、
所在

放射性物質

、初期

溶

推察

、全

燃料

。

得
裏付
掘

燃料

出

事実

東京電力

。

観測
起

得
。本稿

公表
、東京電力

。

資料

汚染水

累積貯蔵量、併呼称） 塩素

、毎週
濃度

毎月

冷却水量

水
。

水

1）

放射性物質

分析結果―水処理。

更新

2）

放射線強度 塩素

137

一年間 新

処理水量（

、

公表

上

整理 、2018 年 10 月、

。原子） 汚染状況

、「福島第一原子力発電所周辺

放射能濃度測定結果―」

濃度 時間変化

動機

、原子炉内

報道資料

呼

内

放射線強度

放射性強度

最初

、燃料

考察

迫

毎週公表

放射能（

放射性汚

。

塩分）、地表一時貯蔵

137

論証

全

資料

上

追跡

、当初生成

挙動

水

検討

収

、前報

取

時間的経過

安定

、放射性汚染水

・

。本

。
冷却水中

格納容器内

、福島第一原発建屋内
。

5 稿目

考

残留分

設備

。本稿

本稿

塩素

物理化学的状態

137

過

判明

中心 検討 加。

2．原子炉建屋周辺の地下水の概要（1）建屋周辺の断面の概略と地下水制御施設の概要
図− 1
模式的

福島第一原発
示

不透水層
山側近傍

上

建造

T/B 海側近傍施設

数多（

断面（東西方向） 地下水制御施設。原子力建屋（以下、R/B

側遮水壁（凍土壁） 複数
水

建屋（1 〜 4 号機）周辺

設置

。不透水層
数十本

突

抜

形

海側

建屋（以下、T/B

被圧地下水層設置。一方、T/B 海側
、更

）

透水層

及

不透水層

設置

下

呼

設置

。
。更

海側遮水壁（鉄鋼矢板） 張

51

。）

呼

）

。R/B
囲
西

T.P.+2.5 m（O.P.+4 m）地盤

、T.P. (Tokyo Peil )：東京湾平均海面、O.P.：現地平均海面

概要

巡

形

山側

陸

地下

地下水
。

（O.P.+4 m） 地には地下水ドレンがは海側遮水壁（
東京湾

海

）が
、O.P.

り

地

多く

置されており、 にその海側にで、T.P. (Tokyo Peil )らされている。
（
海

である。
）

西側

(

(

)

)

水
T.P.+8.5m 地水
T.P.+2.5m 地

海
水
水
水

(

水

)
水

(

)
水

図−１

図－１

福島第一原発の建屋周辺の断面と地下水制御施設の模式図

福島第一原発の建屋

の

と地下水

の

図

T.P.+8.5 m 地盤

、西（2）T.P. +8.5 m 地盤における地下水の挙動. P . 3)+ 8 . 5 m
東京電力 ）T資料に2, 3, る、1,

約 1.4 km

幅

4水の
号機

約 1,000 m /day

側 約 800から
1.4 kmm /day
揚水の囲 では、西の

は、原子炉
。

建屋を

山側斜面

が 。原発事故前
地する T.P.+8.5m地、原子炉主建屋で 海 1,000
排出 m

3海 とされる。原発
自然流出

立地

、
1, 2, 3, 流
および
地下水
込 4

3
東京電力の資料 3)によれ

3

3
/day
、残の地下水が流れ
約 200 m /day

800 m

ドインにより

3

地下水

/day

3
m /day の地下水が海に流 mして水されて海に排/day 程度
現在が、凍土壁
西 山側 され、掘削 りの12 本200地下水揚水用井戸、300 〜 350

3いたものとされる。
地下水
揚水、放射性濃度
T/B

在は、
壁の西の
迂回
海 排出

2015300～350
m /day年 9 月以降、。

側にされた 12）。 の地下水
（地下水

汲

上

地下水

。

、水質

運用目標未満上 、R/B

水用T/B）周辺 地下水位
度の地下水が度をチェ
主建屋（R/B 水され、放射性
調整

3

排水

高 場合 目標濃度以下 浄化
4)

から、
して

浄化

い場
常時稼働
後

4
表−１

凍結開始前からの陸側遮水壁内側 (T.P.+8.5m 地盤 ) の水収支の変遷
2016 年1 月−3 月
凍結開始前

凍結完了時

現在

m3/daym3/daym3/day

F

810

630

400

降雨涵養量（建屋周辺地盤） E1

‑50

‑105

‑110

降雨涵養量（建屋屋根） E1r

‑30

‑65

‑70

420

510

440

0

0

0

180

120

140

310

110

60

‑20

50

‑60

810

620

400

凍土壁内側への地下水流入量

サブドレン揚水量

A

閉合範囲外への鉛直移動量
建屋への流入量DB

凍土壁から海側への地下水流出量
地下水変動への寄与量

C

E2

A+B+C+D+(E1+E1r) ＋ E2

2017 年9月

2018 年9月＊ここで、A：実測値、B：実測からの推定値、C：実測からの推定値、D：仮定、（E1+E1r）：実測からの推定値、E2：実測からの推定値（−値は地下水位上昇を示す）＊＊建屋屋根降雨の内、周辺地盤への浸透分が E1r であり、屋根損傷部からの建屋直接流入分は B に含まれる

52

海

地下水位

、雨量

、及

、

揚水量

実測値

（凍結開始前、凍結完了時、及、2018 年 9 月） T.P.+8.5 ｍ地盤

。凍結完了

揚水量

5)

、

壁内側

地下水流入量800 m /day

水流入量

約 50 m /day、

凍土壁

3

3

400 m /day、

地下水流出量

三期間
、表− 1

変化

3

減少

推定

水収支

400 m /day 程

3

海側

基

応

、凍土

、主建屋

約 250 m /day 減少

地下

。

3

（3）T.P. +2.5 m 地盤層における地下水の挙動
T/B 東側

T.P. +2.51 m 地盤層（原子炉建屋
。
、

点在
前報

移動中

土壌粒子

、全β及

。下部透水層
述

地層

137

海側地盤）

懸念

数多

、2014 年 7 月

濃度

観測井

検出

公表資料 以後

見当

、

。

地下水位

、降水量

、

基 推定

三期間（凍結開始前、凍結完了時、及 、2018 年 9 月）

揚水量、及 地下水

。凍土壁 効果

8)

結果、
表−２

検出

6)

払拭

程度減少

高
濃度

7）

支 、表−2

設置

吸着
無視

水質結果

自由地下水観測井

、凍土壁

地下水

海側

揚水量

揚水量 実測値
T.P.＋2.5 ｍ地盤 水収地下水流出量250 m3/day

220 m3/day 程度減少。

凍結開始前と現状の陸側遮水壁外側 (T.P.+2.5m 地盤 ) の水収支の評価
2016 年1 月−3 月凍結開始前2017 年9月

2018 年
9月

凍結完了時

現在

m3/daym3/daym3/day

310

110

60

降雨涵養量（T.P.+2.5m 地盤） R

‑40

‑80

‑60

ウェルポイント汲み上げ量

80

20

10

240

150

90

0

0

0

30

30

30

0

0

‑10

310

120

60

凍土壁から海側への地下水流出量
W

地下水ドレン汲み上げ量G

閉合範囲外への鉛直移動量
海への地下水流出量
地下水変動への寄与量

C

D

S
Eg

R ＋ W + G + D + S + Eg

＊ここで、R：実測からの推定値、W：実測値、G：実測値、D：仮定、S：実測からの推定値、およびEg：実測からの推定値（−値は地下水位上昇を示す）

3．放射性汚染にかかる諸水量の概要（1）原子炉内での放射性汚染水の発生
原子炉
放射性物質

冷却水
生成

低温安定状態

保

。現在

、燃料
、当初生成

53

、初期

新
溶

出

各種

残留分

冷却水中

放出

考

（長期 FP呼）。

9)（2）原子炉冷却水量と放射線汚染処理水量の推移
2011 年 6 月以降、循環式冷却。主建屋（R/B

T/B）内 汚染水 周、周辺地下水位

T.P.+2.5 m (O.P.+4.0 m) 以下、主T.P.+1.5 m 前後 保持操作

辺 地層 漏 出
建屋内 滞留槽 水位

正式稼働

循環冷却
以下
力

化

低下

、1 号機

、将来的

図− 2

R/B

T/B

原子力建屋

3

一環

、2016 年 3 月

間

汚染水

1 号機 R/B

連結

循環冷却

除去処理水量

図中 実線 処理水量35日移動平均値。冷却水量 、4

落 着

因

、
表− 3

。一方、
装置停止

、放射線汚染水、2016 年度

発生量

400 m /day

要因 、T.P.+2.5 m 地盤
原因 、凍土壁
day

大幅

大

。降水起源

建屋流入地下水量・。

2017 年 3 月下旬以

3減少

15 m /day

海側

地下水流出量

建屋流入量

目標

。
3

310 m /day

180 m3/day

抑制

120 m3/day

達成

代替、2020 年中

汚染水発生量150 m3/day(m3/day)

処理量(m3/d)

1400

処理量35日移(m3/d)

水量と処理水量

1200
1000
800
600
400
200
2018/9/27
150

200

250

300

350

(week)

400

図−図−２
原子炉への
水
量と
ウム 137
汚染水の処理量の週変化
原子炉への冷却水供給量とセシウム
137 汚染水の処理量の週変化

表－

減少
。

水量(m3/d)

100

60 m3/

閉塞、T.P.+8.5 m 地盤海側（陸側遮水壁外）

1600

50

総量

。減少 最大半減

190 m /day

1800

0

。

10）

11）

0

原

。汚染水発生量
3

。

低減

。

考

3

100 m3/day

水位低下、、薬液注入水

示

段階 経

変遷

175 m /day

。凍土壁

、

週変化

1)

。東京電

除去装置 用

要因別実績

凍結完了

減少

。2018 年内
東京電力

、三

建屋移送量

維持

除去処理水量 方 週変動 大2018 年度 4 月‑7 月期間

3状況

T.P.+1.7 m

。

冷却水量

降 約 205 m /day

水位独立、2018 年 9 月
3

。

54

放射線汚染水の発量の実

2016 年度

2017 年度の変2018 年

表−３

放射線汚染水の発生量の要因別実績の変遷
2016 年度

2017 年度
実績(m3/day)

2018 年4 月­ 7 月(m3/day)

150

95

90

建屋流入量（屋根損傷箇所からの流入）

30

35

30

T.P.+2.5m 盤からの建屋移送量

175

35

15

汚染水発生の要因

実績(m3/day)

建屋流入量（地下水等の流入）

薬液注入量

20

20

15

廃炉作業に伴い発生する移送量

25

35

35

汚染水発生量

400

220

190

3.7

3.8

3.6

参考：降雨量

図− 3
HTI

呼

建屋

図－ は、 建屋内のたまり水量、、 主建屋内
水量、ス建屋内のたまり水量、HTI
内の建屋内
水量、 高温焼却炉建屋（以下、

1)
およびそれらの合計水量の週変化を示したものである）たまり水量、
内
水量、合計水量 週変化 示 。

建屋と HTI のたまり水量は、変

水量

HTI

いといえる。一方、主建屋内10 月）(mm/d)

水量はあるものの、変動

特段、 建屋内のたまり水量には

明

減少傾向

認

の

増加傾向

らかな減

に、第 275 週あたり（2016 年 10 月）からの減

減少率 大量も 。
てたまり水

ス

も減

減少傾向

。特

が

、第 275 週

同様

。
。一

られる。

率が大きい。それを水総量な反映を示している。

1)

もな（2016 年

し

傾向

示

。

量 (m3/day)

130000120000

建屋内(m3)110000HTI(m3)
水合計(m3)

ス建屋(m3)

10000090000
80000

建屋内のたまり水

70000
60000
50000
40000
30000
20000
10000
2011/6/1
2011/10/1
2012/2/1
2012/6/1
2012/10/1
2013/2/1
2013/6/1
2013/10/1
2014/2/1
2014/6/1
2014/10/1
2015/2/1
2015/6/1
2015/10/1
2016/2/1
2016/6/1
2016/10/1
2017/2/1
2017/6/1
2017/10/1
2018/2/1
2018/6/1
2018/10/1

0

図－
図−３
図－

図− 2

基

3

m /dayとなったデータから 2017 年度の処理水量の日440 m3/day である。一内

一方、図− 3の建屋内のたまり水の量の週変化
主建屋内のたまり水の貯留量の週変化

基

水日

減量の

値を

205 m3/day および汚染水発

。
量に

、図－

2017 年度

2018 年 4 月中から、

求

建屋内滞留水日低減量

値 220 m3/day（表－値
日冷却水量 205 m /day
している。
3

日平均値

30m3/day となる。 の値と日2017 年度

るとになったデータから 2017 年度の建屋 3

の

処理水量

ると

量

値を

。

約 440 m /day
水量平均値）の合計量は日処理

求約 30

汚染水発生量平均値 220 m /day（表− 3）

水中の放射強度を

55
9

減さ

る

3

とを

に、

合計量

日処理量

対応

。

2018 年 4 月中旬、滞留水中 放射強度 低減
目的 、ウム除去装置による処理水の
を直接
建屋に
水する
イン（
処理水 余剰分 直接主建屋 注水（滞留水浄化設備） 稼働

除去装置
水浄 期間
。

3
3
建屋
化
）が
している。 の期 の日
水量は 205 m3/day であり、、主建屋内滞留水 低減量 平均値 約 45 m /day
。汚染水
日冷却水量 205 m /day3
内
水の 3 減量の値は 45 m /day である。汚染水発量値を 1903、三者 合計量 約440 m /day。
合計量 日処理水
発生量平均値 190 m /day3
440 m3/day となる。 の合計量と日処理
3m /day とすると、三者の合計量は
3
差、約 70 m /day 滞留水浄化設備 回。今後、量
量（510 m /day）
水量（510 m3/day）との 、 70 m3/day が水浄化に されている程度
不明、現在 倍程度 増加
余地 十分
考
。
とになる。 後、 の量が の 度になるかはであるが、 在の
度に

する

地は

にあると考えられる。

（3）一時貯蔵タンクの処理水量の推移
却水

除去処理水
塩分 の
除去 水 の後、一部 循環式冷却）
循環 ウム除去処理水は、残系外 貯 が除去された後、一。貯蔵は以外 各種放射性物質
するた
に
水として

下、ALPS 等される水は、
呼 ）
存

汚染
され、

りが

放射性物質除去冷

水 ス、 ムを 137（以
外に 、多核種放射性物質除去設備
えられる とになる。

各種放射性物質除去
ウム 以外
137 とストンチウム以外の。
染されているので、多維持

上 一時貯蔵
放射性物質により汚（以下、ALPSと）でト

図− 4 リチウム以外の汚染水 日処理水量放射性物質が除去された上で一時日処理水貯蔵量 推移 示
。 タン

に

存される。

図－４に汚染水の日処理水量と日処理水

保量の推移を示した。

1200
日処理水
1000

(m3/day)

両者の(m3/day)

2017/9/20

800

2017/5/23

日処理水量35日移

量

600
400
200

2018/9/15

2018/11/14

2018/7/17

2018/5/18

2018/3/19

2018/1/18

2017/11/19

2017/7/22

2017/3/24

2017/1/23

2016/9/25

2016/11/24

2016/7/27

2016/5/28

2016/3/29

2016/1/29

2015/11/30

0
2015/10/1

汚染水の処理水量と処理水(m3/day)

量35日移

図－４ 汚染水の日処理水量と日処理水貯蔵量の推移
汚染水の日処理水量と日処理水
量の推移
図−４

一時貯蔵

貯蔵

137日処理水量変動2018 年 10 月現在、ALPS 等

処理水
良増加速度（日処理水貯蔵量） 、大変動
103
対応 、2017年4月以降 平均値 約260 m /day
水除去汚染水） 量56

量約 94 万 m 、

処理

、
。

処理水（塩分3

約 15 万 m

3

。

12)

2018 年 10 月

在、ALPS

ンチウム処理水（

と

15

の量は

により処理された水の量は
ウムとスト

94

、スト

m

ンチウムのみが除去された汚染水）

m3 となっている 12)。

の汚染水の濃度変化の4．原子炉建屋内の汚染水の濃度変化の解析（1）循環式冷却システムの概要
１）
図− 5

循環式冷却
図− は

の 要
概要説明図
ス ムの

m 程 日水205冷却。原子炉
現在 毎日 205在は図である。原子炉は
3。冷却、一旦、各 R/Bにm 3 使の水で 水 されている。

T/B 地下室 、貯留。両建屋内
れた水は、一R/B およびT/B の水

地下 に 維持される。両建屋内のたまり水は、をするた に地下、設定水位
地下水流入分 冷却水分 水相当
量
建屋
水流入 と
水 に 状況する量がス建屋もしくは
HTI に移送される。
HTI 移送
。
応
主建屋以外
汚染水
移送
（表
れらには状況にて 建屋以外からも汚染水が移送されてくる（表－
137 を
）。
建屋 滞留
汚染水
、
参照の と）。 れら建屋にする汚染水はポンされ、ウム 137
除去
後、塩分 除去。
とスト ンチウムが除去された後、が除去される。

−3

参照

一時

qg+

タン

水 qc

原子炉建屋

水化装置

原子炉
ウム 137
除去装置

地下水 qg

たまリ水
量 V
度 C

汚染水 qg+qc

図− 循環式冷却システムの概要説明図
ス ムの
図
図−５

2018 年 4 月初旬
一時貯蔵
建屋

11
、処理水 一部

、図− 5
貯

注水

。

冷却水

循環

、残

系外

、2018 年 4 月中旬以降

、処理水

余剰分

直接主

、

・

（滞留水浄化設備） 併

稼働。

（2）原子炉たまり水中の汚染物質の濃度（強度）の推移
滞留

中

137（Cs137） 放射線強度用資料
385 週分
1
月

毎週公表
整理

。

結果

示

月間隔

。

東京電力

約1

Web

（T） 放射線強度

Cs137 濃度2011 年 9 月 20 日
、東電（Cl-）濃度、2011 年 6 月 15 日

。汚染水

月間隔

Cl- 濃度

公表

資料 2)

57

。図− 6

2011 年 7 月 5 日

記載

対数、Cs137表示） 示

2018 年 11 月 1 日。

値、、2011 年 92)半対数紙表示（濃度値2018 年 9 月 20 日

Web 上

、毎週

時間変化
用

週変化
Cl- 濃度

毎週公表

分析

1）

（T） 放射線強度。Cs137 放射線強度、
放射線強度

塩素

代用

、300 週以降。

、T
HTI

放射線強度、および Cl- 度は 2011 年 7 月 5 日から 2018 年 11 月 1 日まで、T
放射線強度は 2011 年 9 月 20 日から 2018 年 9 月 20 日までとなっている。なお、
度については、東電の Web 上での資料 2)に300 週以降の HTI の Cs137
れている強度でさ用した。

1.00E+10

Cs137 (Bq/L)

1.00E+09

トリチウム(Bq/L)
イ

1.00E+08

ン(ppm)

Cs137, T, Cl-

1.00E+07
1.00E+06
1.00E+05
1.00E+04
1.00E+03
1.00E+02

0

50

100

150

200

250

300

350
400
(week)

図− セシウム
ウム
強度、トリチウム強度および
イ ン 度の週変化
図−６137137
強度、トリチウム強度および塩素イオン濃度の週変化
121）セシウム 137 の放射線強度
図−6、Cs137

直線的

低減 、第 80 週

10 Bq/L） 漸近

放射線強度
様態 示

7

2011 年 7 月5日

2.1×109 Bq/L

半対数紙表示低減率、第 125 週辺

一定値（約 1.9 ×。

始 第 278 週辺 （2016 年 10 月中旬）
、第 279 週
年 6 月）
図− 6
求

建屋

平均値

平均値

濃度

汚染水

。
、第 1 号機 T/B

後濃度上昇

、

以降 1.0×10 Bq/L 前後
、

建屋

、両建屋

水

HTI
汚染水

放射線強度

考

来

、平均値

厳密

放射線強度

変化

水

復水器内

高

第 360 週辺 （2018
。

移送

主建屋内
移送

続

推移

8

。第 278 週以前

、

急落
。

達

、再 、下降

。原因
13)

放射線強度

Cs137

上

移送

1.14×10 Bq/L

主建屋以外

跳

7

8

示

後、第 240 週辺 （2016 年 2 月）
1.0×107 Bq/L

、3.0 × 10 Bq/L

濃度汚染水

小

放射線強度

滞留量

主建屋内

水

、第 279 週以降
主建屋

水

Cs137

。

2）トリチウムの放射線強度
図− 6

水

水

、淡水化装置

含

T

入口

採取

4.2×10 Bq/L低減

後、第 250 週辺

1.0×10 Bq/L 迄下

。

後上昇

Bq/L

上昇

。

染濃度

約 1/2

達

第 279 週以降

後 2.0×10 Bq/L T 前後
6

、懸念材料
図− 6

値

推移

一

主建屋内

転

水

58

用

、2011 年 9 月 20 日

、第 160 週（2014 年 7 月上旬）

。

5

合

直線的

漸近

約 3.0×10 Bq/L
5

。分析

。T 放射線強度

半対数紙表示

6

示

低減

続

、第 278 週目採取

第 360 週辺 （2018 年 6 月）
。

値

、

。前報

検討

訂正

放射線強度

正

反映

2.6×106
初期汚

、

場
。

3）塩素イオン濃度Cl- 濃度、2011 年 7 月 5 日

週 (2013 年 1 月 1 日 )9 日）

16,000 ppm
約 300 ppm

徐々

上昇

転

漸近

、半対数紙表示

直線的

傾向、第 180 週（2014 年 12 月

、第 230 週辺 （2015 年 12 月）があったが、第 180 週（2014 年 12 月 9 日）あたりから

く

低減

、第 80

記録

960 ppmに上に。

1 週14 日）280 週辺
、第 239 週（2016
境 年低下
続 、第
年 11 月） 時点
て、第年
230月
り（201512 月）には960 ppm
を （2016した。しかし、第340 週
下。 年 後、約前後下し 上昇239 週（20161 月 14 350
日）ppm
を に
、第、第
280 週
り（2017（2016年
年12
11月）
月）辺

200 ppm
650 ppm
図− 6

越 の時 では200 。
ppm まで下がった。その後、

350 ppm

後まで上

し、

12 月）
りからは 650 ppm を越えるよ
Cl- 年
示 第 340 週（2017濃度、淡水化処理装置入口 採水 になった。
汚染水

第278週以前

水化処理装置入りで示されている
建屋 HTICl の移送度は、 汚染水
主建屋内 で

図－、度である。第 278 週以

水のCl- 濃度

考

HTI

移送

。

主建屋内

外

汚染水-

度と考えてよい。しかし、第 279 週以降は

Cl

建屋

濃度

の Cl-

ったので、図－度は。

水された汚染水、、第 279 週以降

主建屋以

ス建屋と HTI に移送される汚染水はCl- 濃度建屋内のたまり水

水

は、

図− 6
内

約

建屋内たまり水の、図− 6Cl- 濃度

建屋以外からの汚染水が主建屋

Cl- 濃度水 ス建屋もしくは。
HTI に移送されてくるので、図－の Cl- 度は 建屋内のたまり水の Cl- 度そのものではない。

（3）たまり水の汚染物質濃度変化の無次元表示
図− 7

T 放射線強度 Cl- 濃度、Cs137 ）たまり水の汚染物質濃度変化の
図—

示

週変化

初期濃度値

は、Cs137 および T の放射線強度と Cl- 度の週変化をそれ

無次元化

れの初期

。

度値で無次元化して示したものである。
01.00E+00

100

300(week)

400

2018/9/27

Cs/Cs0
イ ン
トリチウム
トリチウム予測値、T、Cl−
初期値で無次元 表示したCs１

200

1.00E-01

1.00E-02

1.00E-03

無次元表示の
イ ン 度、
ウム137
137放射線強度、および放射線強度、および
無次元表示の塩素イオン濃度、セシウム
トリチウム放射線強度の週変化（初期値で無次元化）
トリチウム放射線強度の週変化（初期値で無次元化）

図−
図−７

T

放射線強度

初期値

。図中

強度

14)

週変化

三者

直線

第 330 週

、東京電力

無次元表示
存在

FP

減水率14 用場合、第 150 週

示唆週変化2011 年 7 月 5 日、長期 FP

。第 160 週以降

値

逆算

予測
実測値

乖離

値
T

大

放射線
、長期

。
、過去 4 報（福島第一原発建屋内

59

水

放射性

T の放射線強度の場合、第 150 週までの減水率を用いて 2011 年 7 月 5 日の値を逆算しその値を初期値とした。図中の直線は、東京電力が、長期 FP ソースタ
ームがないと予測した T の放射線強度の週変化 14)の無次元表示である。第 160
週以降は実測値との乖離が大きくなっており、長期 FP ソースタームの存在を示唆している。

汚染状況16), 17), 7)
三者の第33015),
週までの週変化については、過去４報（福島第一原発建屋内の参照。
解析（1）〜（4）
たまり水の放射性汚染状況の解析（１）～（４））15), 16), 17), 7)も参照されたい。

1）たまり水の汚染物質濃度変化の要因に関する考察

１）たまり水の汚染物質濃度変化の要因に関する考察、原子炉建屋内 流入
地下水・雨水水量、、地下水
図－８は、原子炉建屋内に流入する地下水・雨水水量、および、地下水ドレ（海側遮水壁 西側 隣接）
建屋
移送量 推移 示。作図 用
ンとウェルポイント（海側遮水壁の西側に隣接）からの建屋への移送量の推移
18）
。著者
、2016
年 1 月〜 2018 年 10 月 東京電力
報道配付資料を示したものである。作図に用いたデータは、2016
年 1 月～2018 年 10
月の東 、地下水

図− 8

）
18
汲 上
地下水
、専用 浄化処理装置。著者は、地下水ドレンとウェルポイント
京電力からの報道配付資料である

外

以

放射性物質
除去
後 港湾内 排水考
、実際 、多から汲み上げられた地下水は、専用の浄化処理装置によりトリチウム以外の放時

800 m /day 射性物質が除去された後に港湾内に排水されていると考えていたが、実際は、
越 汲 上 水 原子炉建屋 移送。
多い時には 800 m3/day を越す汲み上げ水が原子炉建屋に移送されていた。
3

原子炉建屋に流入する諸量(m3/daｙ)

1300
1200

地下水・雨水流入量

1100
1000

地下水ドレンとウエル
ポイントからの移送量

900

両者の合計

800
700
600
500
400
300
200
100

2018/11/1

2018/9/1

2018/7/1

2018/5/1

2018/3/1

2018/1/1

2017/11/1

2017/9/1

2017/7/1

2017/5/1

2017/3/1

2017/1/1

2016/11/1

2016/9/1

2016/7/1

2016/5/1

2016/3/1

2016/1/1

0

図－８ 地下水ドレンとウェルポイントからの原子炉建屋への移送量の推移
図−８ 地下水ドレンとウェルポイントからの原子炉建屋への移送量の推移
15

配布資料
、「地下水
水

設置
、浄化処理
近

行

井戸

流

量

減少

状

、台風

約 200 m /day 前後
約 180 m /day

地下水

大雨

変動

約 120 m /day

汚染水
。

止

地下水

上

確認後

、海洋

地下水

取

。
排水

上

地
、原

移送量

。流入量

変動

水

移送

60

、

。

、地下水・雨水流入量

凍土壁陸側部凍結開始後
建屋

組

19)

。2016 年 1 月〜 9 月

上

Web
、地下

減

・

低減
汲

量

行

。」 説明

起因

関

組

。2016 年 12 月初旬
3

廃炉

増加

満

、地下水・雨水流入量

3

込

海側遮水壁

図− 8
急増減

、東京電力

』取

、排水基準

地下水

3

量

原子炉建屋等

護岸

子炉建屋等

理由

、汚染源 『漏

、地下水
下水

見逃

降水

、

流入

原因

。
、2015

年 10 月

海側遮水壁

完成

、T.P.+2.5 m 地盤層
量

急増

。

地下水位

上昇

、一部

、移送量
年3月

後
建屋

変動

開始

。2016 年 10 月以降
、図− 8

挙動

移送

HTI

結果

流出地下水量処理

必要100 m /day

低減

T.P. +2.5 m 地盤層

、移送量
踏

大幅

抑制
汲

3

300 m /day
凍結

海

地下水

3

凍土壁海側部以下壁

3

100 m /day

、図− 7

動向

。2016 年 1 月〜 9 月。低減

地下水流出量3

20 m /day 弱低減

Cs137、

T示、第 230 週（2015 年 11 月）以降

生

中心

考察

上

原因

、2016

減少

考
。

放射線強度

Cl- 濃度対応。

。

2）セシウム 137 とトリチウムの放射線強度の週変化
第 160 週以降
前報

、Cs137

、
。
汲

不明

、汚染度

水

原子炉建屋
上

移送水

T

Cs137

放射線強度

T

T

放射線強度

地下水・雨水考第 279 週
水

前報

強度

跳

、東京電力

事前

予測

Cs137

T

Cs137
、Cs137濃度、qb：主建屋以外
qc1：第 280 週以降
根破損部

、上昇

理由

急降下

薄

効

考

。

、台風
上

放射線

水

移送

上昇
、T

(qbCb+γ)/qt1

汚染水生。）Cs137T続。

高濃度滞留汚染

。）

放射線強度
移送

量、γ：放射性物質

冷却水量、qg1：第 280 週以降

考21)、Cb：主建屋以外

移送

降水流入量

第 365 週（2018 年 6 月中旬）。
（第 1 号機 T/B 復水器内

放射線強度

。（

漸

、(qbCb+γ)/(qg1+qr1)
汚染水

放射性物質

溶出率、qt1 = (qc1+qg1+qr1+ qb)、

地下水流入量、、qr1：第 280 週以降

第 360 週辺

漸近値

屋

向

。

2018 年 4 月中旬
設備

滞留水浄化設備稼働。滞留水浄化設備

稼働

放射線強度

漸近値

、第 384 週時点

改善（下降） 期待

3)

下降

HTI

100 Bq/L以下、放射性物質濃度

汲

上

放射線強度

近

度

主建屋
、前者

地下水

T

入

考察

、

、地下水

。

移送

HTI

流入

考

規模

水

Cs137

大量

見当

放射線強度

建屋内

期間中 Cl- 濃度

低

形跡

移送

第 278 週辺 （2016 年 9 月中旬） Cs137
汚染

変化、300 〜 100 m /day

、移送水

300 〜 800 Bq/L

低減

溶出率γ

3

20)

、

継続的

第 278 週第 270 週 (2016 年 8 月中旬 ) 辺
水。

第 250 週辺

、放射性物質、第 230 週辺汲。

Cl- 濃度理由分果、Cs137

。

水

移送
後者

低

、図− 8

上

上下動

放射線強度

T

原因
、

挙

放射性強度

T

Cs137
。

直接注水量

(qbCb+γ)/(qt1+qd)

qd

、放射線強

明確

。

同様

。

塩素イオン濃度の週変化

第230週以降

Cl-濃度

週変化

第 278 週辺 （2016 年 9 月中旬） Cl- 濃度

基本的
Cs137

61

Cs137
T

T

放射線強度

比

急降下

、

。

理由

、地下水

時期

建屋

残念

、地下水

HTI

検証
前報

濃度

Cl汲

上

出来

近

Cl-

濃度

現

、

考

汲

上

Cl- 濃度、(qg1Cg1 + qbCb)/qt1

水Cl- 濃度

。

測定値

公表

。
水

流入地下水

Cl- 濃度決。（。）第 360 週辺 （2018 年 6 月）

考。

滞留水浄化設備稼働、Cl-濃度、Cl- 濃度

場合

降） 期待

希釈効果

水

、今後

280 週以降

移送水

漸近値

第 384 週

(qg1Cg1 + qbCb)/(qt1+qd)

時点

明確、Cg1：第
漸近値

向

、濃度

改善（下

。

5．汚染水対策にかかる考察（1）循環式冷却システムの今後
1）1 〜 4 号機たまり水をセシウム除去装置へ直送する配管システム
東京電力 、HTI

建屋、1 〜 4 号機
。

度

水 移送

新移送

21)

貯留

高濃度汚染水

1 〜 4 号機内

直送

SARRY

稼働 始

冷却水

、HTI

循環系統

移送配管設置工事 実施
建屋内 貯留水 放射性物質 強水 放射性物質 強度 反映

稼働後 、1 〜 4 号機

除外

、新移送

水 直接

公示 求

。

2）1 〜 4 号機滞留水浄化設備の設置
東京電力、2016 年 10 月

120 m /day 程度
却水量

冷却水循環

、冷却用淡水注入量

3

汚染水量

減少

、主建屋内

新

処理水

余剰分

稼働

直接主建屋

効果
水

期待
外部

。漸近値
導入

、地下水流入量
増大

続

、当初

冷

漸近値

目的

（滞留水浄化設備） 設置、SARRY、2018 年 4 月中旬

実現

新

漸近値 γ /(qc2+ qg2 + qr2+qd)

漸近

思

効果

期待

、qc2：2020 年以降

冷却水量、qg2：。

、qr2：2020 年以降
新

関

、一時貯蔵

qb → 0

地下水流入量、

濃度

放射線強度

低減

、2020 年度中

直接注水 効果 期待
、T

放射能濃度

注水

直接注水

同様 、Cl- 濃度

。

。
T

Cs137

、主建屋流入地下水量
22)

。

、滞留水中

濃度

滞留水浄化設備

低減

近

。中期目標

、Cs1372020 年以降

水

変更

減

3

漸近値 Ce1、東京電力

200 m /day 程度

270 m /day 程度

移送
数倍高

稼働条件
3

屋根破損部

漸近値 qg2Cg2 /(qc2+ qg2 + qr2+qd)。

、漸近値

γ /(qg2+qr2)
地下水流入量

漸近

。

62

、直接注入
増

段階

降水流入量

、Cg2：2020 年以降 流入地下水

下
実現

、

、
。

思
Cl- 濃度

、
。

漸近値
汚染

低減

（2）汚染水浄化装置
周知

ALPS 等

貯蔵

敷地内

汚染水

増

続
庁内

関

第1回

検討
害

） 設置
会合

報告書」 上申

。報告書

、

必要経費

試算結果

、必要期間

受
目的

水
計 15 回棄、水蒸気方式、「多核種除去設備等処理水

、
行

汚染水

取扱

処理方策

中心

一時

議論

進

、2016 年 6 月 3 日 「汚染水

地中注入、海洋投。

示

23)小委員会」 設置

。小委員

社会的

観点等

含

総合的

9回

小委員会

開催

、主

風評被

。

議論

。2013 年 12 月 25 日

風評被害

24)

観点

開

関

。2018 年 7 月 13 日

、

社会的

貯蔵

汚染水処理対策委員会、2016 年 5 月 27 日

水

会

設置

（

開催

。T 汚染水。

経済産業省資源対策

除去

T

汚染水処理方法、2018 年 8 月末

説明・公聴会。

開催

25)（3）凍土壁
地下水
行

R/B

流入

T/B

防

、2017 年 11 月 3 日

東京電力

地下水

地下水

、東京電力

水位

掲

凍土壁

作

原子炉周辺

取

囲

工事

。

全域凍結

、「凍土壁

、主建屋周辺

、凍結工法
26)

流

完全

目的値

十分制御

可能。」

。2 −（2）、（3） 述

目的

達成

考

、原子炉内

燃料

凍土壁

構築

遮断

、

併用
。

（4）燃料デブリの所在にかかる事柄
4．
却水中

検討

内容

総合的

、現在

当初生成

放出

放射性物質
考

、依然
得

判断

全

、初期 溶

物理化学的状態

出

安定

残留分

冷

。

燃料

格納容器内

収

調査

、全

。下部透水層

地下水質

確認

一

有力 物証

、

福島第一原発建屋内

水

放射性汚染状況

解析

以下

。

確
燃料

論証

格納容器内

形 公表

収

考

。

6．おわりに明（1） 原子炉冷却貯留

伴

放射性汚染水約 110 万 m

3

。

、

汚染水
比率

（2） 第 160 週 (2014 年 7 月 ) 以降
上下変動

対応

処理

順調

進

約 86 %

2018 年内

、前報
。現在
除

100 %

137
。両者

63

通

見込

述

内容

加

、一時貯蔵

全

放射性物質
薄

放射性強度

除去

。
無次元表示

、第 240 週辺 （2016 年 2 月）

第 279

週（2016 年 10 月下旬）
屋

下降

続

。今回

300 〜 100 m /day

及

水

地下水

判明

両者

放射線強度

詳

検討

3

HTI

、

上昇特性

、前報

（3） 第 280 週以降上昇
滞留水浄化設備考（4） 塩素

水
稼働

期間中、

主建
移送

下降

放射線強度
措置

、2018 年 10 月現在、効果

、第 230 週以降

上下変動

、

原因

推察

。第 280 週以降

。

。

濃度

検討

同期

低減

、2018 年度 4 月

137

放射線強度

明確

現

。

上下変動

、基本的

低減

有効
137

。

参考文献
1） 東京電力：福島第一原子力発電所

高濃度

放射性物質

・

資料 .

（第 1 報 ‒ 第 377 報）、東京電力

含

水

貯蔵及

処理

状況

(http://www.tepco.co.jp/decommission/information/newsrelease/watermanagement/index-j.html)
2） 東京電力：福島第一原子力発電所周辺
水処理施設

放射性物質

分析結果 ―水処理設備

放射能濃度測定結果―、

分析結果．( 毎月更新 )(http://www.tepco.co.jp/decommission/data/analysis/index-j.html)
3） 東京電力：福島第一原子力発電所周辺

地質・地下水解析 (PDF 形式 )、経済産業省汚染水処理対策委員会第 5 回（平成 25 年 8 月 23 日）配布資料、資料 3、p.7、2013.
4） 東京電力
9 月 18 日、p.1‒2.

( 株 )：地下水

稼働

伴

地下水

状況

、参考資料、2014 年(http://www.tepco.co.jp/nu/fukushima-np/handouts/2014/images/handouts_140918_06-j.pdf)

5） 経済産業省：廃炉・汚染水対策

会合 第 58 回事務局会議、資料 3‒1、p.26、2018 年 9 月 28 日 .

（http://www.meti.go.jp/earthquake/nuclear/decommissioning/committee/osensuitaisakuteam/2018/10/3-1-6.pdf）
6） 東京電力：下部透水層

水質調査結果、福島県主催「平成 26 年度第 5 回 福島県原子力発電所

安全監視協議会」、参考資料 3‒2、p.1-7,7） 大坪国順：福島第一原発建屋内

水

廃炉

関

2014 年 7 月 30 日．
放射性汚染状況解析（4）、地球環境学、No.13 上智地球環境学会、p.1‒20, 2018.
8） 経済産業省：廃炉・汚染水対策

会合 第 58 回事務局会議、資料 3‒1、p.21、2018 年 9 月 28 日 .

（http://www.meti.go.jp/earthquake/nuclear/decommissioning/committee/osensuitaisakuteam/2018/10/3-1-6.pdf）
9） 内田 俊介：福島第一原子力発電所

汚染水

現状

汚染水中

、日本原子力学会主催

研究会講演資料、p.60-69, 2014 年 4 月 .
10） 経済産業省：廃炉・汚染水対策現地調整会議（第 45 回）、資料 1‒1、p.3, 2018 年 8 月 23 日．
(http://www.meti.go.jp/earthquake/nuclear/osensuitaisaku/committtee/genchicyousei/2018/0823_01_01.pdf)
11） 東京電力(株)：福島第一原子力発電所

廃止措置等

向

（案）、

中長期

平成 29 年 9 月 26 日 廃炉・汚染水対策関係閣僚等会議 資料 2、p10.
(http://www.tepco.co.jp/nu/fukushima-np/roadmap/2017/images2/t170926_04-j.pdf)12） 経済産業省：廃炉・汚染水対策

会合 第 58 回事務局会議、資料 1‒2、p.2、2018 年 9 月 28 日 .

(http://www.meti.go.jp/earthquake/nuclear/decommissioning/committee/osensuitaisakuteam/2018/10/1-2.pdf)
13） 東京電力：1 号機復水器水抜

及配管、廃炉・汚染水対策会合事務局会議（第 35 回）、資料 3‒1‒3、p.1‒4、2016 年 10 月 27 日．
14） 東京電力：福島第一原子力発電所

量及64

多各種除去設備処理水

化学的水質

、

・

資料、2014 .

(http://www.meti.go.jp/earthquake/nuclear/pdf/140424/140424_02_003.pdf)
15） 大坪国順：福島第一原発建屋内

水

放射性汚染状況

解析、地球環境学、No.10 上智地球環境

水

放射性汚染状況解析（2）、地球環境学、No.11 上智地球

水

放射性汚染状況解析（3）、地球環境学、No.12 上智地球学会、p.123‒134, 2015.
16） 大坪国順：福島第一原発建屋内環境学会、p.129‒142, 2016.
17） 大坪国順：福島第一原発建屋内環境学会、p.17‒32, 2017.
18） 東京電力( 株 )：建屋

地下水

移送量・地下水流入量等

推移、東京電力報道

配付資料 2016 年 ‒2018 年(例、http://www.tepco.co.jp/nu/fukushima-np/handouts/2017/images2/handouts_171211_02-j.pdf)

19） 東京電力( 株 )：地下水

地下水汲上(http://www.tepco.co.jp/decommission/progress/watermanagement/groundwater_drain/index-j.html)
20） 東京電力( 株 )：

・地下水

浄水分析結果、東京電力報道配付資料 2016年 ‒2018 年(例、http://www.tepco.co.jp/nu/fukushima-np/f1/smp/2017/images4/drain_stank_17121501-j.pdf)21） 経済産業省：進捗状況一覧表、汚染水処理対策委員会（第 20 回）、参考資料 3

進捗状況一覧表、p.2、

2017 年 8 月 25 日 .
(http://www.meti.go.jp/earthquake/nuclear/osensuitaisaku/committtee/osensuisyori/ 2017/pdf/0825_s03_00.pdf)
22） 東京電力：福島第一原子力発電所 1 〜 3 号機原子炉注水量 低減、廃炉・汚染水対策会合

事務局会議（第 35 回）、資料 3‒5、p. 3、2016 年 10 月 27 日．
(http://www.tepco.co.jp/nu/fukushima-np/roadmap/images1/images2/d161027_10-j.pdf)
23） 経済産業省：

水報告書、 汚染水処理対策委員会（第 18 回）、 参考資料 5、pp.66、2016 年 9 月 27 日 .
(http://www.meti.go.jp/earthquake/nuclear/osensuitaisaku/committtee/osensuisyori/2016/pdf/0927_01k.pdf)24） 経済産業省：多各種除去設備等処理水取扱

関小委員会 ( 仮称 )設置

、汚染水処理対策委員会（第 18 回）、参考資料 6、2016 年 9 月 27 日 .
(http://www.meti.go.jp/earthquake/nuclear/osensuitaisaku/committtee/osensuisyori/2016/pdf/0927_01l.pdf)
25） 経済産業省：多各種除去設備等処理水取扱

関小委員会（第 1 〜第 9 回配付資料）.

(http://www.meti.go.jp/earthquake/nuclear/osensuitaisaku/committtee/takakusyu/001_haifu.html – 009_haifu.html)
26） 経済産業省：陸側遮水壁

効果

関

現時点

評価

、陸側遮水壁

（第22回）、

資料 1‒1，2018 年 1 月 17 日 .
(http://www.meti.go.jp/earthquake/nuclear/osensuitaisaku/committtee/rikugawa_tusk/pdf/180117_01c.pdf)

65Exploring Positive Implications of Eco-labeling Schemeson Sustainable Development Goals
Huiying Cai, Masachika Suzuki
Abstract
Eco-labeling or environmental certification schemes are voluntary commitments to communicate theenvironmental attributes of products and services with consumers. Presently, eco-labeling schemes are
utilized in various sectors including food, electronics, clothing, mining, and others. The objectives of thisarticle are twofold. The first objective of this article is to introduces eco-labeling as a marketing tool forfirms to attract consumers. The second objective is to examine and highlight the potential linkages with
Sustainable Development Goals (SDGs) among eco-labeling schemes in the food industry. Recently, there
are growing interests and needs among both policymakers and researchers to understand the possible
interactions among different SDGs. The result of the study described in this article indicate that several key
SDGs are strongly linked to the issues covered by the eco-labeling schemes. The results of the study suggestthat the companies in the food industry may be able to enhance their social, economic, and environmental
commitments through the use of eco-labeling schemes. It may be also possible to use the eco-labelingschemes as a marketing tool by informing consumers not only about the environmental but also socialand economic attributes of the products and services that the consumers would not recognize otherwise.

67

環境ラベリング制度と持続可能な開発目標 (SDGs)の正の関連性の検討

蔡慧穎・鈴木政史

概要
環境ラベリング制度（環境認証制度）は企業が消費者に対して商品やサービスの環境面での特性を知らせる自主的な取り組みである。現在、環境ラベリング制度は、食品、電気、衣服、採掘な
どの様々な産業分野で導入されている。本論文の目的は 2 つある。1 つの目の目的は企業が消費者を取り込むためのマーケティングツールとして紹介することである。2 つ目の目的は、食品産業で導入されている環境ラベリング制度のレビューを行い、それぞれの制度と持続可能な開発目
標 (SDGs: Sustainable Development Goals) との関連を検討し明らかにすることである。現在、政策立案者及び研究者の間で SDGs の間の関連性を理解しようとする関心とニーズが高まっている。
本論文で紹介する研究の結果は、研究対象とした環境ラベリング制度が主要な SDGs との強い関連性を示している。この結果を受けて、本論文の結論は食品産業の企業が環境ラベリング制度の活用を通して、環境面だけなく社会・経済面におけるコミットメントを高めことができる可能性を指摘すると共に、消費者の間で認識されていない環境・社会・経済面の様々な取り組みを消費者に周知するツールとしての環境ラベリング制度の可能性を指摘した。

68Exploring Positive Implications of Eco-labeling Schemeson Sustainable Development Goals
1. Introduction
Eco-labeling or environmental certification schemes are voluntary commitments to communicate
the environmental attributes of products and services with consumers. They can be useful and effective
tools to bridge the gap between production and consumption of products and services by informing theconsumers about the environmental attributes of the products and services that consumers would notrecognize otherwise. They can be an effective marketing tool to attract “green consumers.” In order toobtain an eco-labeling, the target products or services typically need to go through a verification process
conducted by a third party. They can be certified with eco-labeling if they meet required environmental
criteria. Presently, eco-labeling schemes are utilized in various sectors including food, electronics, clothing,mining, and others.

The objectives of this article are twofold. The first objective of this article is to introduces eco-labeling asa marketing tool to attract consumers. The first part of the article describes the main drivers for producers
and retailers to obtain eco-labeling and illustrates possible marketing implications for them. The second
objective is to examine and highlight, if there are any, the potential linkages with Sustainable Development
Goals (SDGs). Eco-labeling schemes in the food industry are the focus of this study. While the scope ofmany eco-labeling schemes typically limited to the environmental issues, the schemes may have positive
implications on economic and social issues covered under SDGs. Recently, there are growing interests
and needs among both policymakers and researchers to understand the possible interactions among
different SDGs (Nilsson, 2017). While SDGs are well-recognized both in the public and private sectors, theunderstanding of the inter-linkages among various goals is lagging behind.

2. Introducing eco-labeling as a marketing tool of products and services
2.1 What is ecological or green marketing?
Various articles indicate that there are “green consumers” who seek to purchase “green” food products.
In order to meet their demand, many food and retail companies produce and promote food as eco-products,
sustainable products, bio-products and green products in the market. According to a European Union (EU)Council Regulation, many of these products are categorized as organic food by the government at first(Council Regulation No 834/2007, 2007). However, the term “organic” is simply referred as product itself
rather than the whole production process. In the case of the EU, the EU Council defines organic process as“combines best environmental practices, a high level of biodiversity, the preservation of natural resources,
and the application of high animal welfare standards” (Council Regulation No 834/2007, 2007).

69

And yet, consumers still hold the confusion towards the meaning of “green” or “organic.” In thiscircumstances, the green marketing has emerged as an approach to create an opportunity for both companies
and consumers to have a better understanding of greenness (Charter, 2017). Some literatures have regarded
green marketing as an approach for firms to verify themselves as environmentally-friendly organizations
by combining their market environment (such as consumers and competitiveness) and non-market
environment (such as regulators and citizens) together (Teisl & Roe, 2005).
As indicated above, various terms are being used to identify the relationship between business marketingand environment such as environmental marketing (Iyer, Coddington, & Ottman, 1994), ecologicalmarketing (Dyllick, 1989), and sustainable marketing (van Dam & Apeldoorn, 1996). These green strategies
sometimes can be regarded as part of their efforts for information disclosure (Prakash, 2002) to help
consumers to compare various environmentally sound products and services. In this context, eco-labelingschemes are often being introduced as a useful and effective tool for the producers to disclose informationand for consumers in the choice of the products and services.

2.2 What are the main drivers for producers and retailers to obtain eco-labeling?
Some literatures illustrate that the main motivation for firms to obtain eco-labeling is to respond toexternal market pressure from various stakeholders such as “green consumers” and improve their market
competitiveness (Iraldo & Barberio, 2017). In other words, the market factors such as adding the values ofcurrent products and expanding a new market could be the main drivers for firms to apply for eco-labeling.
More specifically, many firms attempt to send the environmental information, through eco-labeling, that
affects consumers’ decisions on choosing products. In many cases, eco-labeling is an intermediate to build
a bridge between producers and consumers with environmental sound products (D’Souza, Taghian, Lamb,& Peretiatkos, 2006). Some literatures point out another drive for firms to obtain eco-labeling. They indicatethat obtaining eco-labeling could be an opportunity to improve their product image or reputation by going
through a third-party certification process and proving the superior ecological performance of products
or services (D’Souza, 2004).
While scholars suggest that eco-labeling schemes are beneficial for green consumers who wish to identify
environmental products, various research have questioned whether premium on environmental soundproducts and services can increase the sales (D’Souza, 2004) as the cost of eco-labeling (due to the fee paid
to consultants, funding, and licenses) may increase the prices of such products and services. When “green”
recognitions are lacking by a majority of consumers, the relatively higher cost of the products and services
can become a main barrier to promote eco-labeling. Nevertheless, as stated above, eco-labeling is often
recognized as a useful tool to help consumers looking for some criteria to justify their purchases (D’Souza,
2004) based on positive contributions to the global environment. It is reasonable to state, therefore, that
eco-labeling can be unique approach to link environmental concerns and environmentally responsible

70

purchasing to marketing strategies.

3. Research design
This study examines and highlights, if there are any, potential linkages with several different
Sustainable Development Goals (SDGs). While the scope of many eco-labeling schemes typically limited
to environmental issues, the schemes may have positive implications on economic and social issues covered
under SDGs. Indeed, there are growing interests and needs among both policymakers and researchers tounderstand the possible interactions among different SDGs (Nilsson, 2017). While SDGs are well-recognizedboth in the public and private sectors, the understanding of the inter-linkages among various goals is lagging
behind. Some scholars indicate that there are both positive and negative interactions among different SDGs.
While there may be synergies among various SDGs (positive interactions), trade-off or cancelation of eacheffort among different goals (negative interactions) is also conceivable.
This study focuses upon the positive interactions between eco-labeling schemes and various SDGs in
the food industry. It attempts to identify SDGs in selected food eco-labeling schemes and provide crosssectional information on the food eco-labeling schemes. As stated above, many firms attempt to integrate
environmental considerations into business or marketing strategies through eco-labeling in order tomeet consumers’ demand for the products and services with clear indications of environmental superior
attributes. This is also the case with the food industry. For consumers, when they go to a retail store topurchase food, reading an eco-labeling is the starting point to explore how the products are positioned in
an environmentally sound fashion.
While many of the existing food eco-labeling schemes tend to emphasize the single dimension ofenvironment-related issues such as the use of organic component (e.g. EU organic labels) or animal rights(e.g. Animal Welfare Approval), the single dimension only reveals the limited information about the
products (Ridoutt, Sanguansri, & Harper, 2011). Therefore, this study copes with 11 general food eco-labelingschemes that are not focusing on a single dimension of environmental issues.
Figure 1 classifies those 11 eco-labeling schemes into four groups based on their main scopes and aims.
Group I (UTZ Certified, Demeter, LEAF and Food Alliance Certified) focuses mainly on creating sustainable
management in the farming practices, while eco-labeling schemes in Group II (AENOR Certification, Global
GAP and Milieukeur) place priority on sustainable outcomes such as sustainable products and services in thefood industry. Fair Trade Organization Mark, one of the most widely recognized ethical labeling schemes,
is classified into Group III, as it is the only scheme with the main focus placed upon the social issues forthe farmers and workers in the food production chain. This labeling scheme is an exception in this study
as the main scope of the labeling scheme is not environmental issues. Lastly, Group IV including Marine
Stewardship Council, DeLaval and LODI RULES emphasizes one specific food product such as fish, dairy

71

products as well as wines.
Figure 1 illustrates the possible interactions between selected eco-labeling schemes and SDGs. As
preliminary research has indicated that several SDGs including 1, 4, 9, 10, 11 and 16 are not strongly related
to eco-labeling schemes, Figure 1 does not indicate the relationships between the labeling schemes andthose goals.

4. Review results
As seen in Figure 1, SDG 12 (Sustainable Production and Consumption) is relevant to all eco-labelingschemes in the food industry reviewed in this study. This is because SDG 12 attempts to build the connections
between production and consumption. Indeed, the use of eco-labeling scheme is encouraged under thisgoal as follows:“There also needs to be significant focus on operating on supply chain, involving everyone from producer to
final consumer. This includes educating consumers on sustainable consumption and lifestyles, providing themwith adequate information through standards and labels and engaging in sustainable public procurement,
among others.” (UN Environment)
SDG 12 aims to improve the quality of life without increasing environmental deterioration and foster the
emergence of eco-labels (Horne, 2009). As indicated above, the food-related eco-labeling schemes can be auseful instrument to communicate the environmental performance of products or services from the supply
side (Thøgersen, Haugaard, & Olesen, 2010). They can connect the production side and the consumption
side and are likely to help to improve the quality of life of consumers.
Apart from SDG 12, SDG 2 on sustainable agriculture is also a fundamental goal there are related to all
11 food eco-labeling schemes. SDG 2 integrates food security, nutrition and sustainable agriculture which
are essential parts in food industry and being emphasized in every food eco-labeling scheme reviewed inthis study. It is reasonable to recognize that the most targets set under SDG 2 support the progress of SDG
12 and vice versa. For example, sustainable agriculture, which is the core target of SDG 2, aims to increasing
productivity and efficiency in the farming practices, and directly contributes to all parts of SDG 12 (Mollier,
Seyler, Chotte, & Ringler, 2015). Similarly, the sustainable natural resources and the increase in productivity
encouraged under SDG 2 directly support SDG 12 with respect to the management of chemicals and efficientuse of water and resources.
In addition to SDG 2 and SDG 12, there are other goals that are interacting with eco-labeling schemes.
The four eco-labeling schemes in Group I aim to improve the sustainable management practices in farming.
These schemes support to improve the working conditions, achieve equality (SDG 8) and protect life on

72

73

Demeter

Linking

Food
Alliance
Certified

I

I

I

IV

IV

IV

III

II

II

Certification and labelling scheme towork together with existing brands, andshow that consumers that products havebeen sourced, from farm to ship shelf in asustainable manner.
Demeter is the largest certification
organization for biodynamic agriculture.
LEAF (Linking Environment
Certification and labelling scheme thatcertifies farms, ranches, and food processors
and distributors for sustainable agriculturaland facility management practices.

Brief

DeLaval
LODI RULES for Sustainable Winegrowing
is C a lifor niaʼs or ig ina l sust ainable
viticulture program. This program truly
began from the ground up, with grape
LODI Rules growers deciding it was important for the
future of the Lodi region. Our certification
process is rigorous, based in science,
voluntary, and third-party accredited andaudited.

DeLavalMarineThe MSC is an independent, not for profit,
Stewardship international body based in the UK. It was
Council initiated by the

AENOR
Ecolabel system aimed at recognizing
Certification
Global G.A.P. is a private sector body thatsets voluntary standards for the certification
Global Goodof agricultural products around the globe.
Agricultural
The aim is to establish one standard forPractice
Good Agricultural Practice with different(Global GAP)
product applications capable of fitting to
the whole of global agriculture
The Dutch environmental quality label for
Milieukeur
products and services. The
This label connects disadvantaged farmers
and workers with consumers, promotes
Fair Tradefairer trading conditions and empowers
Organization
farmers and workers to combat poverty,Markstrengthen their position and take more
control over their lives.

UTZ
Certified

I

II

Name

Group

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

SDG 7
Affordable
and Clean
Energy○○Clean Water

SDG 6

○

○

GenderQuality

SDG 5

○

○

SDG 2
SDG 3
Zero Hunger
Good Healthandand
SustainableWell-being
Agriculture

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

○

SDG 8
SDG12
Decent Work Responsible
andConsumption
Economic
andGrowth
Production

Figure 1: Possible interactions between selected eco-labeling schemes and SDGs

○

○

○

○

○

ClimateChangeSDG13○Life Below
Water

SDG14

○

○

○

○

○

○

○

○

Life on Land

SDG15

○

○

○

○

○

○

○

○

○

Partnershipfor the Goals

SDG17

land (SDG 15). The food industry is expected to provide livelihood for the poor and vulnerable people andimprove the poor economic development. By improving the working conditions and creating equal job
opportunities for both women and men which is the main part of SDG 8, the eco-labeling schemes can help
to promote sustainable economic growth. With respect to SDG 15, the goal supports sustainable agricultural
production and genetic diversity in order to protect, restore and promote sustainable use of terrestrial
ecosystems. Those four eco-labeling schemes in Group I may help to promote sustainable agricultural
production and therefore they are likely to be linked to the goal as well.
It is also noted that some eco-labeling schemes reviewed in this study have direct interactions withspecific goals. The focus of the UTZ and Food Alliance Certified is sustainable management of water (SDG
5), while the other two in Group I (Demeter and LEAF) is directly linked sustainable use of energy (SDG 7).
In the case of the UTZ, the impacts of food upon mental, emotional and physical health are also consideredin the certification process, as the quality food and nutrition status are a fundamental driver for health andwell-being. As such, the linkage between the eco-labeling scheme and SDG 3 on good health and well-being
is observable. On the other hand, SDG 5 indicates that empowering women in agriculture through increasing
their decision-making over agricultural production and incomes has been shown to improve both family
health and nutrition outcomes. From this perspective, the eco-labeling schemes such as the UTZ have thedirect and indirect interactions with SDG 3 and SDG 5.
While the labeling schemes in Group II pay more attentions to sustainable outcomes such as productions
and services rather than the process or management of practices, the goals related to environmental issues
including SDG 6, SDG 7 and SDG 15 are linked to those schemes in Group II. In the case of AENOR
and Milieukeur, they are specifically related to SDG 13 that requires the reduction of GHG emissions inagriculture. Group IV contains labeling schemes that have strong focus business areas such as fishery, dairy
farming and wines. Each eco-labeling scheme in this group is directly and/or indirectly linked to different
SDGs. While the main focus of the MSC is the life in the sea (SDG 14), DeLaval and LODI cope with the
improvement of energy efficiency in business operations (SDG 7).

5. Conclusion
This study illustrated the positive interactions between eco-labeling schemes and SDGs. The study
analyzed 11 schemes in the food industry. The results of the study indicated that SDG 2 and the SDG 12
have the strong connections with them. It turns out, however, that they are also strongly linked to otherenvironmentally-related goals such as SDG 6, SDG 7, SDG 13 and SDG 15. In addition, the goals in the socialand economic dimensions such as SDG 3, SDG 8 as well as SDG 17 are also associated with the labelingschemes in the food industry sector. The results of the study suggest that the companies in the food industry
may be able to enhance their social, economic, and environmental commitments through the use of ecolabeling schemes. It may be also possible to use the eco-labeling schemes as a marketing tool by informing

74

consumers not only about the environmental but also social and economic attributes of the products andservices that the consumers would not recognize otherwise.
Note: The brief introductions of each labeling schemes in Figure 1 are taken from various sources oninternet. The research was supported by the Environmental Research and Technology Development Fund
(S16-4) of the Environmental Restoration and Conservation Agency of Japan.

References
Charter, M. (2017). Greener Marketing. Routledge. https://doi.org/10.4324/9781351283526
Council Regulation No 834/2007. (2007). Retrieved fromhttps://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32007R0834&from=EN
D’Souza, C. (2004). Ecolabel programmes: a stakeholder (consumer) perspective. Corporate Communications:
An International Journal, 9(3), 179–188.
https://doi.org/10.1108/13563280410551105
D’Souza, C., Taghian, M., Lamb, P., & Peretiatkos, R. (2006). Green products and corporate strategy: anempirical investigation. Society and Business Review, 1(2), 144–157.
https://doi.org/10.1108/17465680610669825
Dyllick, T. (1989). Ecological Marketing Strategy for Toni Yogurts in Switzerland. Retrieved fromhttps://link.springer.com/content/pdf/10.1007%252FBF00383035.pdf
Iraldo, F., & Barberio, M. (2017). Drivers, Barriers and Benefits of the EU Ecolabel in European Companies’
Perception. Sustainability, 9(5), 751.
https://doi.org/10.3390/su9050751
Iyer, E., Coddington, W., & Ottman, J. (1994). Environmental Marketing: Positive Strategies for Reaching theGreen Consumer. Journal of Marketing, 58(2), 127.
https://doi.org/10.2307/1252276
Nilsson, M. (2017). Important interactions among the Sustainable Development Goals under review at the HighLevel Political Forum 2017. Retrieved from www.sei-international.org
Prakash, A. (2002). Green marketing, public policy and managerial strategies. Business Strategy and theEnvironment, 11(5), 285–297.
https://doi.org/10.1002/bse.338
Ridoutt, B. G., Sanguansri, P., & Harper, G. S. (2011). Comparing carbon and water footprints for beef cattle
production in Southern Australia. Sustainability, 3(12), 2443–2455.
https://doi.org/10.3390/su3122443
Teisl, M., & Roe, B. (2005). Evaluating the factors that impact the effectiveness of eco-labelling programmes.
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https://doi.org/10.1177/027614679601600204

75

Families and SDGs Goal 5:
Parental Leave Policies and Gender Equality
Keiko Hirao*
Abstract
This paper explores how family policies can positively enhance gender equality that SDG Goal 5 aims toachieve. In recognition to the global attention given to gender equality vis à vis work-and-family conflict,this paper gives special attention to the impact of family leave policies on women’s career outcome andmen’s participation in unpaid work. Literature from 1990s was reviewed among which evaluative studies
that adopt experimental design were selected for further examination. The major findings are two-fold. First,
longer and generous parental leave policies do not necessarily promote gender equality in the labour market.
They encourage mothers to delay their return and thus jeopardize long-term advancement of their career,
resulting in perpetuating gender gap in economic rewards. Second, parental leave reserved for fathers, as abenefit non-transferable to mothers (daddy quota), is a promising scheme to encourage fathers to take leavefrom work, especially when this benefit is provided as bonus period of ‘take-it-or-lose-it’. Gender equality inthe public sphere can never be achieved unless unpaid domestic work and care work is shared more equallyin the private sphere. Future family policies should give more attention to the contradicting demand thatthey are trying to fill. They must ensure well-being of children while making sure that equality between
genders is promoted.

*

Sophia University, Graduate School of Global Environmental Studies77持続可能な開発目標と家族政策
̶育児休業制度の効果̶

平尾

桂子

概要
ジェンダーの平等（持続可能な開発目標 Goal5）の達成に対する育児休業制度の効果を検証する。子どもを養育する労働者を対象とする休業制度は、パプアニューギニアを除く全ての国と地域で制定・施行されており、世界的に休業期間、補償内容ともに拡大される傾向にある。本論
では、1）女性の労働供給および賃金格差、2）男性の育児休業取得および実際の育児参加に注目し、その政策変化の効果を文献研究により検証した。レビューに用いた文献は、1）政策変化の事前・事後における、2）縦断的ミクロデータを用いた（疑似）実験法（quasi-experimental design）により因果関係を明らかにする研究に限定した。その結果、1）育児休業の長期化は総じて女性の労働供給を低下させ、労働市場におけるジェンダー平等には必ずしも効果的ではないこと、2）男性の育児取得率の向上には父親しか利用できないパパ・クォーターが有効だが、実際の育児参加に対する影響は限定的であることが判明した。家族は、その形こそ多様化したが、依然として社会の結合力や生産性の源泉であり、文化を次世代に伝える中心的制度の一つであることに変わりはない。持続可能な開発目標の達成に向けて家族政策の視点の重要性が示唆される。

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Families and SDGs Goal 5:
Parental Leave Policies and Gender Equality
Introduction
The past four decades witnessed a substantial progress toward equality of gender. When the United
Nations General Assembly adopted the Convention on the Elimination of All Forms of Discrimination
against Women (CEDAW) in 1979, a majority of girls living in the world did not have a chance to grow up
imagining what they might be able to do in the future, except for getting married and being mothers. There
have been substantial advances since then in women’s legal rights, educational opportunities, health status,
employment, and decision-making power. Much of the progress has been credited to the voices of womenand advocacy agents that promoted international conventions, treaties, resolutions and following legislativechanges in member nations that pledged to be bound by the international agreements.
The progress toward gender equality, however, is still far from complete. We still observe persistentgender segregation horizontally and vertically; women are overrepresented in the informal economy, parttime jobs with little job security, and in low-paying occupations, such as domestic service and care work.
Vertical gender segregation is still prevalent, and the women’s share of top management in large corporations
is still unacceptably low. It is expected to take more than 70 years before it is completely closed (ILO,
2016b). Gender inequality remains an assiduous challenge for the international community as a significant
obstacle to sustainable development. The Goal Number 5 of the 2030 Sustainable Development Goals (SDGs),
therefore, aims to continue the progress that the international society has made for gender equality.
This paper seeks to contribute our knowledge of how family policies can positively enhance genderequality that SDG Goal 5 aims to achieve. Specifically, this paper tries to answer the following two questions:
What is the impact of parental leave on women’s labor force behavior and their income?
2. Which designs of parental leave policies are most likely to encourage men’s take-up rate and increase
their participation in unpaid work?
This paper pays particular attention to the effect of policies that address work and family conflict becauseof the following two reasons. First, the interplay within family profoundly affects the power relationshipbetween men and women through the allocation of roles and responsibilities for domestic work andupbringing of their children. Gender inequality in the public sphere is both the cause and the result of
the disparity in the private area. How men and women spend their time within their family mirrors andreproduce the differences in their access to resources outside the home, namely income and political power.

*

This research was conducted as a part of Family and the 2030 Sustainable Development Agenda, aninternational research project sponsored by the International Federation for Family Development (IFFD)
and United Nations Department of Economic and Social Affairs (UNDESA). An earlier version of thispaper was presented at the Expert Meeting for SDGs & Families Global Project, held at the UN Headquarterin New York, U.S.A. (December, 2017).

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Second, reconciling work and family conflict is one of the most challenging conundrums facing
humanity. As a society, reasonable economic growth must be maintained, and at the same time, sound caremust be provided for upbringing the next generation to keep a society sustainable. The competing demands
for production and reproduction are particularly acute in developed countries where fertility has long fallen
below replacement levels.
This paper consists of four sections. After a brief description of SDGs Goal 5, part three gives the general
overview of parental leave policies around the globe and then presents the global evidence on how they affectthe women’s career outcome and men’s contribution to domestic work.

Gender Equality in Sustainable Development Goals
Goal 5 of the SDGs aims to achieve gender equality not only as a fundamental human right but also as anecessary condition for attaining peaceful, inclusive, and sustainable development. Although gender equality
is enshrined as a stand-alone Goal of its own, it is a cross-cutting issue and is deeply interlinked with manyof the other SDGs such as poverty (Goal 1), food security (Goal 2), health (Goal 3), and education (Goal 4).
For example, women still make up a high proportion of people living in income poverty (e.g., Chant, 2006),
and gender equality is expected to contribute to the reduction of poverty through improvement in women’s
income, health, education, and access to and control over land and other resources.
Sustainable Development Goal 5 consists of six outcome targets and three sub-targets. These targets
show the practical starting points and translate that gender equality refers to ending discrimination (5-1),
violence (5-2), and harmful practice against women and girls (5-3). Equality between the sexes also means
equal rights in the public sphere that include: access to economic resources and land ownership (5-A), equal
opportunities for leadership in political, economic and public life (5-5), which are supported by soundpolicies enforceable legislation that promotes gender equality and empowerment of women and girls. In
tandem with women’s empowerment in the public spheres, Goal 5 also calls for recognition of unpaid careand domestic work. Through a provision of public services and infrastructure as well as the promotion ofshared responsibility within the household and the family, the target 5-4 aims to enhance acknowledgmentof care work and domestic work that are unpaid.
This paper identifies target 5-1 (ending discrimination) and targets 5-4 (recognition of unpaid work) as
the focusses that are most pertinent to family perspective. It also defines gender equality as equal access tomonetary rewards and an equitable distribution of unpaid work between men and women as measured bygender wage gap and the time used in unpaid work. As noted earlier, this paper focuses on policies aiming
at balancing work and family responsibilities as the critical elements for gender equality. The following
sections will give the general overview of parental leave policies and then presents the global evidence on
how they affect women’s career outcome and men’s contribution in domestic work.
Parental Leave Policies and Gender Equality: Review of Literature
Parental leave policies are almost universal today, but at the onset, they started as policies to protect

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maternity. It goes back to the first International Labour Conference in 1919 when the Convention onmaternity protection was adopted (Convention No. 3). It was initially designed to promote the health of amother and her newborn baby by providing a mother time to physically recover from the childbirth andalso to build psychological attachment to her newborn child. It was later developed as a statutory provisionof the right to return to the previous employment so that the female workers would not be discriminatedagainst for the maternity reasons.
As of this writing, all countries except Papua New Guinea have laws mandating some form of parental
leave (ILO, 2014). There are significant variations in the duration and level of compensations of the provisions
among countries. The job-protected leave available to either parent varies from 12 weeks in the United States
to 156 weeks in France, Germany, Poland, and some other countries in East Europe. A majority of countries(98 out of 185 countries as of 2013) provide at least 14 weeks of maternity leave among which 42 countries
meet or exceed the 18 weeks of leave proposed in the Recommendation No. 191 (ILO, 2014). Among theOECD countries alone, maximum job-protected leave for mothers varies from 12 weeks in the United States
to 166 weeks in Spain. The amount of cash benefit and its source also differ widely. The average payment rate
for mothers as measured by the percentage of the national earnings of 2014 vary from no payment in the
United States to 100 percent coverage in Spain and Netherland. (Olivetti & Petrongolo, 2017)
The recent trend is toward expansion in the leave coverage. Canada, for example, increased paid familyleave about 25 weeks to 50 weeks in 2000. In 2004, the state of California strengthened maternity rights,
allowing for up to 6 months of maternity leave. Other countries that have recently extended the parental
benefit include the United Kingdom, 2003, 2007, Denmark 2002, and in Germany 1979, 1986, 1992, and1993 (Schonberg & Ludsteck, 2014). Sweden was the first country to introduce gender-inclusive leave policy
in 1974 that enabled mothers and fathers to share six months of parental leave. Other developed countries
began to supplement “maternal leave” for mothers around the time of childbirth with “parental leave” tocare for the children in their early years (OECD, 2017).
The literature that examines the effect of family policies on gender equality can be roughly categorized
into two groups: 1) cross-country approach and 2) within-country approach. The cross-country approachtries to capture the impact of policies using comparative aggregate data compiled by internationalorganizations. The variables employed, however, are inevitable coarse and leave many of the unobserved
heterogeneities unspecified, which makes identification of causal impact impossible. Moreover, family
policy is very complex and does not stand-alone by itself. It has to be studied in conjunction with manyother legislation that affects families, such as tax and pension system, employment regulations, pay equity
between part-time and full-time work, availability of subsidized daycare and early childhood education,school hours, demand for parental involvement for school children, and so on.
Because of these limitations in cross-country research, this paper focuses on within-country approachthat examines the impact of specific policy interventions. By using longitudinal microdata (on pre- andpost- policy reform) this approach enables a natural experimental design of policy assessment. This method
is by far more robust in specifying the causal impact of a particular policy. A drawback of this approach isthat it can consider only one policy intervention at a time. The challenge, therefore, is the generalizability81on how a particular program in a specific time and place can be applied to a different cultural and social
setting. With these limitations in mind, the following section will present the results of the literature review.

Literature Search
The literature search was undertaken in February-March and June-August 2017, using Web of Science(WOS) and a combination of EndNote search engine connected to EBSCO and PubMed. The first round of
search used the topic word such as “family policy,” “gender equality,” (WOS, 68 hits, with oldest publishedin 1996), “parental leave” and “gender equality” (WOS, 107 hits with oldest published in 1990). EndNote
directly connected to Thomson Reuter WOS Core Collection with the keyword search “gender equality” and“family policy” found 401 articles with oldest published in 1994, “gender equality and “parental leave” hit
135 articles from 1990. A further search was conducted to identify the source references in relevant articles
that reviewed the literature.
Once the list of literature was built, they were selected by conceptual coherency, methodological andscientific validity. Papers that met all three standards were included in the study. Table 1 and 2 in the
Appendix provide the list of the articles accepted for the review in this paper.

Parental Leave Policies on Women’s Career Outcome
Thirty years of research on gender-impact assessment of parental leave policies have found mixed andsomewhat enigmatic evidence. While some scholars claim that generous leave policies have some favorable
effect on female labor market outcome (Gornick, Meyers, & Ross, 1998), there have been serious concerns
raised about the unintended adverse effect on gender equality. It is argued that developed welfare states
facilitate women’s access to the labor force, while at the same time, such policies are negatively associatedwith women’s prospect of reaching a higher position in the labor market compared with men (Mandel &Semyonov, 2006). That is, nations characterized by progressive and “family friendly” policies tend to havea high level of gender segregation that disfavors women. (Charles & Grusky, 2004; Mandel, 2012; Mandel &Semyonov, 2006). The negative association between the generosity of parental leave entitlement and women’slabor outcome, as known as “welfare state paradox” has been a focus of debate for some time.
Theoretically, the impact of parental leave on gender equality is ambiguous. It may foster employment
by allowing mothers who would have withdrawn from the labor market and also by encouraging women
who were not previously employed to work for pay because leave benefit makes employment more plausible.
Conversely, parental leave mandate increases the labor cost and may prompt employers to engage instatistical discrimination.
The changes in parental leave policies in many countries have enabled the quasi-experimental design
to assess the impact of policies on women’s labor outcome. In the United States, when Family and Medical
Leave Act (FMLA) was enacted at the federal level in 1993, 12 states and the District of Colombia had alreadystipulated similar leave provision (Waldfogel, 1998). This staggered introduction of legislation enabled Baum82

(2003) to assess the effect of parental leave policies. Using National Longitudinal Survey of Youth (NLSY) anddifference-in-difference estimator he did not find a significant impact of legislation on the wages of women.
Likewise, Hofferth and Curtin (2003) assessed the effect of FMLA using the 1984-1997 wave of Panel
Study of Income Dynamics (PSID) and its 1997 Child Development Supplement. The findings suggest that
only in states that had not passed leave statute, women who gave birth after the passage of the FMLA in 1993
were more likely to return to the same job. That is, although it was not as powerful a job retention policy as
paid leave, unpaid leave can help workers retain their jobs. On the other hand, the passage of FMLA was not
associated with an increase in wage in the two years after birth (Hotterth and Curtin 2003).
Using a similar approach, Waldfogel (1998) examined the effect of childbirth and parental leave policies
on women’s earning in the United States and Britain. The data used were NLSY for the U.S. and National
Child Development Study (NCDS) for Britain. She found heavy motherhood penalty in both countries; about
40-50 percent of the wage gap explained by the parental status that women are penalized for having children,
and another 30-40 percent by the family status, that mothers taking more time out of the labor market.
The result also showed that women who had parental leave and returned to work after childbirth received awage premium that offset the adverse wage effects of children. This positive effect is partly explained by theemployer characteristics (in the United States) and previous wages (in Britain), but after controlling thesefactors, the premium of leave entitlement remained significant (Walfogel 1958).
In Austria, Lalive and Zweimueller (2009) and Lalive et al. (2014) examined the effect of sequentialchanges in leave benefit in 1990, 1996, and 2000. The 1990 reform extended the job protection and cash
benefit from one year to two years; the 1996 change kept the job protection period unchanged but decreased
the cash benefit period from two years to 18 months; the 2000 reform increased the cash benefit to 30 years
while keeping the job protection at two years. Using the Austrian Social Security Database, they comparedmothers’ career outcomes for those who had childbirth before and after these policy changes. The analysis
found that longer leave durations significantly delay mothers’ return-to-work. Nevertheless, despite thesignificant delays of labor force reentry of mothers exposed to the more generous leave regimes, no evidence
was found that the delay had any detrimental effect on their labor market outcome in the medium-run(Lalive et al., 2014; Lalive & Zweimueller, 2009).
In Germany, sequential reforms that expanded maternity leave coverage took place in the late 1970s to
2007. Schonberg and Ludsteck (2014) examined the effect of these policy changes by constructing complete
work histories of men and women covered by the Social Security Records. The results show that eachexpansion in leave coverage reduced mothers’ post-birth employment rates. In the long run (2-6 years afterchildbirth), there was no improvement in mothers’ labor market participation (Schonberg & Ludsteck, 2014).
Using a similar scheme, Gangel and Ziefle (2015) examined the effect of the extension of parental leave
entitlement in Germany. They used the German Socio-Economic Panel (1990–2004 waves) and found that83

increasing generosity of leave right leads to a decline in mothers’ work commitment in both East andWest Germany. They conclude that policy-induced shifts in mothers’ preferences contributed to hindering
women’s labor force participation.
Similar policy impact of shaping employment behavior was confirmed in Australia when paid leave
became available in 2011. The policy provided entitled mothers up to 18 weeks of paid leave with theAustralian minimum wage. Using Household, Income and Labor Dynamics in Australia, Hondralis (2017)
found that women who gave birth after the reform did postpone their return to work until the end of theentitlement period. Women with higher education react strongly to the available policy and markedly adjust
their employment behavior.
Baker and Milligan (2008) examined the impact of policy change in Canada where job-protected leave
provisions are under provincial rather than federal. Using the panel sample and between-province timeseries data created from the Labor Force Survey from 1976 to 2002, they find that modest leave entitlementsof 17-18 weeks do not change the length of time mothers spend away from work. However, longer leaves dohave a substantive impact on behavior, leading to more time spent at home.

Parental Leave Policies and Fathers’ Take-up and Participation in Unpaid Work
Gender equality cannot be achieved unless men take a more active role in parenting. The European
Union Parental Leave Directive 2010/18 recommended that non-transferable parental leave for fathers be
introduced. Today, leave entitlement for fathers is granted in 79 countries out of 167 for which data are
available (ILO, 2014). Among the OECD countries, 26 states provide at least a few days of paid leave thatcan be used only by fathers (OECD, 2016).
The duration varies widely from only one day in Tunisia to one year in Japan. In spite of the prevalenceof legal entitlement, the take-up rate of fathers has been meager. Less than 1 percent of leave recipients are
fathers in the Czech Republic; 2 percent in Finland and Poland, and 3 percent in Austria (INLPR, 2012).
However, in countries where leave entitlement for father is non-transferrable and is well paid, fathers are
more likely to take the leaves. This trend is most prevalent in Nordic countries (INLPR, 2012).
Sweden was the first country to introduce gender-inclusive leave policy in 1974 that enabled either
mothers or fathers to share the period of parental leave. The actual men’s take-up rate, however, did notchange until 1995 when the Swedish government decided to create what is called “daddy month,” a month ofparental leave exclusively reserved for fathers. In 2002, a second daddy month was added (Ekberg, Eriksson,& Friebel, 2013).
Norway is another head runner that introduced four weeks of fathers’ quota in 1993, two years before
such policy was adopted in Sweden. The fathers’ quota in Norway has been extended to 14 weeks throughprogressive reforms and then decreased to 10 weeks in 2014 (NAV, 2014). Iceland provides fathers the largest
non-transferable share of parental leave; three months reserved for the father, three months to the mother,and three additional months that can be allocated between parents (Steingrimsdottiry & Vardardottirz,2015). Likewise, Quebec in Canada established a “daddy quota” in 2006. It is operated through the Quebec84Parental Insurance Plan (Patnaik, 2016). In Germany, too, non-transferable paid paternity leave is establishedin 2007 (Kluve & Tamm, 2013).
The existing literature suggests three critical findings. First, as a direct effect, non-transferable “daddyquota” increased the take-up rate of parental leave by fathers. In Norway, the introduction of “daddy-quota”
in 1993 increased the take-up rate of fathers from 3 percent before 1993 to 60 percent in 1995 (Rege & Solli,2013). Iceland introduced a reform in 2001 that give parents an option to add one month of parental leave in
addition to the allotted six months on the condition that the father uses the additional month. The reform
created substantial incentives for fathers to be more involved in caring for their children during their firstmonths of life, and the take-up rate in the first year was 82.4 percent (Steingrimsdottiry & Vardardottirz,2015). In Sweden, the incentive provided by the “daddy month” encouraged men to take approximately
15 days longer parental leave which accounts for about 50 percent increase from the pre-reform average(Ekberg, Eriksson, & Friebel, 2013). A similar effect was confirmed in Germany (Kluve & Tamm, 2013) andin Canada (Patnaik, 2016) where fathers’ take-up rate of parental leave increased after the introduction of
non-transferable paternal leave. This evidence shows that parental leave period that is non-transferable tomothers (“use-it-or-lose-it” quota) is a powerful instrument to increase men’s participation in parental leave.
Second, findings on the effect of policy reform on fathers’ involvement in childcare and domestic work
are mixed. In a cross-section cross-time research daddy quota is found to be associated with men taking
more time within the family and child care. This association, however, is observed only among highly
educated fathers, and no effect was identified for fathers with lower levels of education (Boll, Leppin, &Reich, 2014).
Ekberg et al. (2013) operationalized involvement in childcare as whether or not parents use the leave tocare for sick children. Their result indicates that Swedish fathers in the treatment group are no more likely
to take time off from work to take care of sick children than the control group who did not have a choice forthe “daddy quota.” In Germany, Kluve and Tam (2013) find that fathers are not more involved in childcare
beyond the period of leave allocated for them.
On the other hand, in Canada where “daddy-quota” was introduced, Patnaik ( 2016) finds that
introduction of “daddy quota” in Quebec province was effective in changing gender dynamics within thehousehold not only for short-run but also for 1 to 3 years after the reform. Using the time diary data from
Canada’s General Social Survey (GSS), Patnaik found that fathers spent 37 minutes longer in non-market
work per day while mothers reduced their time spent in housework by 18 minutes.
Third, there is some evidence that the “daddy quota” lead to fewer conflict regarding the division ofhousehold chores. Kotsadam (2011) find that daddy quota introduced in Norway reduced the level of conflicts
over household work within couples, but this does not necessarily mean that men are doing more of thehousework. Rønsen and Kitterød (2015) report that after the introduction of the reform in Norway, especiallyin the mid-2000s, women returned to work significantly faster. However, they failed to disaggregate theeffect of policy reform and the expansion of subsidized daycare services that was initiated at the same time.
In Iceland, the introduction of the “daddy quota” is credited for more marital stability. After the reform,
the fathers entitled to paternity leave were less likely to divorce during the first years of children’s life85

(Steingrimsdottiry & Vardardottirz, 2015).
In sum, providing father-specific leave seem to increase men’s participation in parental leave, at least
when they are well-paid. The countries mentioned above have the compensation of 80 to 100 percent of pay
during the paternal leave. We cannot overemphasize the importance of monetary benefit because the leavedecision can be driven by simple financial logic. Regardless of the policy design, there is a strong incentive
for a couple to allocate their time for paid and unpaid work according to the comparative advantage (Becker,
1985, 1991). Given the persistence of the gender wage gap, it is more likely that fathers would continue
working unless otherwise compelled. In this respect, merely providing fathers with an exclusive entitlement
for leave is not enough; it must be not only well-paid but also be offered as an extension as “use-it-or-lose-it”
option for fathers.

Conclusion and Discussion
This paper examined how family policies can contribute to gender equality that SDG 5 aims to achieve.
The outcome indicators used in this study are women’s career outcome (represented in wage gap) and time
men and women spend on unpaid work.
As reviewed in this paper, countries characterized by “family friendly” policies with more extended
and more generous leave provisions tend to have a higher level of gender segregation that disfavors women.
Maternity leave policies are expected to promote and achieve gender equality at workplace by securing theright to return to the previous employment position. However, the research finding suggests that the opposite
is true. The studies that use micro-level analysis with natural-experimental design generally find that theprovision of longer parental leaves for childbirth discourages female labor force participation. Although thejob protection of leave entitlement enables more women to stay in the labor force, extension in the durationof leave entitlement or increased wage compensation rate worked as incentives for mothers to spend a longer
time at home after the child birth.
More time at home for parents after the childbirth is the direction that most developed nations areheading. This trend means, in reality, more time at home for mothers and little if any more for fathers.
As noted above, mothers are more likely to delay their return to work as much as the entitlement andcompensation allow them, while fathers do not respond to the leave entitlements. This would increase
the amount of child care and housework done by the mother, and the share of such work and reinforce
the gendered division of housework. The underlining frame of work-and-family conflict continues to bea “women’s affair.” Concerns about the negative consequences of more extended parental leave are mostprominent for higher-skilled, higher-earning professional workers. It is because these workers are hard to
replace, and employers would be reluctant to place women in such jobs that substitution of one worker for
another is difficult. Consequently, an introduction of generous and more extended parental leave, in general,
is found to have an adverse effect on gender equality in the labor market.
On the other hand, fathers’ response to changes in leave policies is minimal. Only when the leave
entitlement is made non-transferable to mothers and provided as bonus period of “take-it-or-lose-it,” fathers

86are more likely to take the leave. Even in an exceptional case where paternity leave is made mandatory(Portugal since 2009), the take-up rate of fathers remains around 50 percent (Wall & Leitaro, 2016, p. 283).
In other words, fathers need to be strongly incentivized or even urged, to take leave from work when they
become parents.
Whether a policy is viewed as effective or not depends on the desired outcome. Parents spending moretime at home means children are receiving more time of parental care at home. From the perspective of childdevelopment, this is a desirable outcome (Waters & Cummings, 2000 ; England & Hiester, 1995). literatureon the importance of the early childcare scheme, however, rarely frame their argument concerning genderequality.
Family policies are often about competition among competing values and embodiment thereof, moreso than other fields of systems. The reproduction of the next generation is the necessary condition of thesustainable future. As family policies are directly related to the nexus of production and reproduction,
they inevitably have to face the question of what is suitable for children as well as what enhances equality
between gender. As Hertz (1999) notes, the extent to which the idea of balancing work and family may be aeuphemism for competing ideals about childrearing, such as professional/commodified services vs. parental(or maternal) care.
The problem between the demands for economic productivity and reproductive capacities of the postmodern societies cannot be solved by achieving gender equality alone. Instead, it is deeply related to ourbelieved values of gender, generation, and class, that are interrelated but often in conflict with each other.
Future family policies should give more attention to the contradicting demand that they are trying to meet.
They must ensure the well-being of children while making sure that equality between genders is promoted.

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coordination in the European Union. European Societies, 7(1), 27-52.
OECD. (2016). Parental Leave: Where are the fathers? Retrieved from https://ssrn.com/abstract=2475970
OECD. (2017). OECD Family Database. from OECD
Olivetti, C., & Petrongolo, B. (2017). The Economic Consequences of Family Policies: Lessons from a Century ofLegislation in High-Income Countries. The Journal of Economic Perspectives, 31(1), 205-230.
Patnaik, A. (2016). Reserving Time for Daddy: The Short and Long-Run Consequences of Fathers’ Quotas.
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88

Schonberg, U., & Ludsteck, J. (2014). Expansions in Maternity Leave Coverage and Mothers’ Labor Market
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89

90

Schoenberg &Ludsteck (2014)

Hofferth & Curtin(2003)

five major expansions in maternity leave
coverage in Germany

Family and Medical Leave Act, Unpaid jobprotected leave

Germany,
East &West

U.S.
FederalGermany,
East &
West

Kluve Tamm (2013)

Gangl & Ziefle(2015)

Germany,
East &
West

Added generousity in parental leave (Eltenge)
from January 1 of 2007. It offers earningrelated benefit of 67% replacement rate for
either father or mother for up to 12 months. Iffather and mother participate, they receive 2
extra months, resulting 14 months of leave in
total

Extension of leave period in 1991 (from12 to
18 weeks), in 1992 (from 18 to 36 months)
and in 2001 (additional flexibility enablingparents to take three-year leave between achildʼs second and eighth birthday.

Country/
regionFamily intervention description

ArticleMothers

Parents

Parents

Parents

PolicyTargetNational

FederalGermany,
East andWest
National

National

Level

results
Found a significant decrease in mothersʼ
employment probability during the 12 months
after giving birth and an increase in mothersʼ
employment probability after the transfer
expires. The implementation of two daddy
months is currently not reflected in significant
changes in fathersʼ time devoted to childcare
Increasing generosity of leave entitlements led
to a decline in mothers' work commitment inboth
East and West Germany. Policy-induced shifts
in mothers' preferences contributed to retarding
women's labor force participation.

Women who return to work are more likely toreturn to the same job after the passage of the
FMLA, but this is true only in states that had
not passed a medical leave statute before theFMLA. FMLA and leave are not associated withincreased wages in the two years after birth.
Each expansion in leave coverage reduced
mothersʼ postbirth employment rates in the shortrun. The longer-run effects of the expansions onmothersʼ postbirth labor market outcomes are,small. 1986 reform, extended paid maternity
leave beyond the period for job security.

Data & Meihods
Survey data from parents with children bornin the first quarter of 2007 and parents withchildren born in the last quarter of 2006.
b efore- and af ter t he refor m, natura lexperimentGerman S o cio-Economic Panel anddifference-in-differences, triple difference,and instrumental variables estimators forpanel data

1984-1997 waves of the Panel Study ofIncome D ynamics and its 1997 Child
Development Supplement

Data: Social Security records from Institutefor Labor Market Research. Complete workh i stor i e s i nclu d i ng t he l e ave p e r i o d.
difference-in-difference design

Table 1. List of articles on the effect of parental leave policies on women’ (quasi-experimental designs)

Appendix

91

Austria

AustriaU.S and
Britain

The U.S.

Canadian
provinces

1 9 9 0 Au s t r i an re for m , e x t e n d i ng j o bprotection and cash benefit from one year to
two years, 1996 two year job protection but
shorter cash benefit period to 18months, 2000
reform; job protection two years, cash benefit
increased to 30 months

Austria, reform increasing the duration ofparental leave from one year to two years forany child born on or after July 1, 1990, AND
reduction of parental leave duration in 1996,
reducing from 24 months to 18months.

U.S. 1993 Family and Medical Leave Act, U.S. 12
weeks of unpaid parental leave and Leave Policies /Britain Trade Union Reform and Employment
Rights Act, July 1993, and European Directive ofCouncil of Ministers, implemented March 1994

1993 Family and Medical Leave Act, U.S. 12
weeks of unpaid parental leave

Canada, reforms in parental leave by provinces.
Modest expansion (from 17 to 18 weeks) in the
1970s, more substantial expansion (to34, 29,52) in the 1990s, andLalive et al. (2014)

Lalive & Zweimueller(2009)

Waldfogel (1998)

Baum (2003)

Baker & Milligan(2008)
Parents

Parents

Parents

Parents

Parents

Provinces

Data: Labor Force Survey from 1976 to 2002.
Two samples, panel and time series of crosssection

Data: NLSY, difference-in-difference -indifference estimator taking advantage ofvariations in state-level maternity leave
legislation and FMLS

Job protected leave can increase the time mothers
spend with their newborns and increase thelikelihood of a return to the pre-birth employer.
Job continuity associated with an expansion ofleave entitlement, but they come from twosources: one from those who continued their jobs
rather than leaving totally, and two from those
who changed to a part-time job.

Maternity leave legislation did not havesignificant effects on employment and wages ofwomen. The result holds true for women who
work for employers that are covered by the
FMLA

Data: NLSY (National Longitudinal Survey ofYouth) for the US and National Child
Development Study (NCDS) for Britain.
NCDS followed babies born in 1958 when
they reached 7, 11, 16, 23, and 33. NLSY
(since 1976) selected British equivalent age
groups. OLS to access the effect of children todifferences in wages (fixed effect model)

Firm/
union
beforeFMLA(1992) in
U.S.
Nationalin Britain

Federal

Women who had leave compensation andreturned to work after childbirth received a wage
premium that offset the adverse wage effects ofchildren.

Data: Austrian Social Security Database(ASSD), individual history of employment,
earning and parental leave take-ups.

More extended parental leave increases fertility(mothers who gave birth their first child after
the reform have more second children thancontrol group) and extended parental leavesignificantly reduces the return to work. The
reversal reform in 1996 increased employment
and earning, but compressing the time between
births.

Longer leave durations significantly delay
return-to-work. Despite the significant delays inreturn-to-work among mothers exposed
to t he more generous le ave reg imes,No
detrimental effects on their labor market
outcomes in the medium-run

National

National

Data: Austrian Social Security Database,Comparing mothersʼ career outcomes for
those who had labor before and after thepolicy changes in 1990, 1996 and 2000 for alength of cash benefits and job protection

92

CanadaNorwayGermany

2011 up to 18 weeks of paid leave, receiving
the Australian minimum wage (approximately
A$673 per week before tax).

introduction of “daddy quota” and its extension
from 4 weeks in 1993, to 14 weeks in 2013 (butreduced to 10 weeks in 2014) research wasadministered before the reduction.

Expansion of job protection period: 1979 (from2 to 6 months)/ 1986 (from 6 to 10), 1988 (from10 to 12 months) / 1992 (from 12 to 18 months)/ 1993 (18 months to 36 months). Maternity
benefit expansion: 1986, 1992, 1993.

Hondralis (2017)

Rønsen & Kitterød(2015)

Schonberg &Ludstook (2014)
Parents

Parents

Parents

National

National

National

Each expansion in leave coverage reduced
mothersʼ postbirth employment rates in the
shortrun. The longer-run effects of the expansions onmothersʼ postbirth labor market outcomes are,however, small.

Panel from Norwegian Labor Force Survey(NLFS).1996-2010

Data: Social Security records, provided by theInstituteFor Labor Market Research. Differencein-difference design that compares labor market
outcomes of mothers who give birth shortly
before and shortly after a change in maternity
leave legislation in years of policy changes andyears when no changes have taken place.

Women do postpone the return to work until theend of the entitlement period. Highly educatedwomen react strongly to the available policy andmarkedly adjust their employment behavior.
Systems have substantial power in shaping
employment behavior.
Wo m e n i n N o r w a y r e t u r n e d t o w o r ksignificantly faster after the policy change.
However, public or subsidized daycare wasgreatly expanded at the same time, so Rønsen &Kitterød did not find that the “daddy quota” wassolely responsible for the timing of work entry

D at a : Hou s e h ol d , In c om e an d L ab or
Dynamics in Australia (HILDA) 2008-2013/2008-2010 pre-reform birth vs. 2011-2-13
post-reform birth/ propensity score matching
and assessed the probability of working in a
specific week after a childbirth93Country/
RegionNorwayGovemment

Government
SwedenDaddy quota in Norway (1993), four weeksof leave reserved exclusively for fathers
which are nontransferable to mothers.

1995 ʻdaddy monthʼ reform. This package
reserved one month of the parental leave tothe father.

Kotsadam &Finseraas (2011)

Ekberg, Eriksson &Friebel (2013)

QuebecNorwayIcelandQuebec Parental Insurance Program in 2006,
that improved compensation and reserved
five weeks of leave for fathers or the “daddy
quota” reserved exclusively for fathers.

Introduction of a paternity-leave quota in
1993, reserving four weeks of the total of 42
weeks of paid parental leave exclusively forthe father.

2001 take-it-or-lose-it paternity-leave quota
given to fathers as an option to add one
month of parental leave to the allotted six
months but only if the additional month
was used by the father.

Patnaik (2017)

Rege & Solli (2013)

Steingrimsdottiry &Vardardottirz (2015)

ArticleFamily intervention description

Fathers

Fathers

fathers

Fathers

fathers

Plicy
TargetNational

National

Provinces

Sweden,National

Norway,National

Level

Find strong short-term effects of the incentives
on male parental leave, but no behavioral effects
in the household. Fathers in the treatment groupdo not take larger shares of the leave period totake care of sick children, which is their measurefor household work. They also investigate asecond data set on fathersʼ and mothersʼ longterm wages and employment, without finding
evidence for substantial effects of the reform.

Data: Swedish registry and employment data.
Assessed involvement in childcare of fathers
as measured whether or not fathers use theleave to care for sick children. Comparison:
fathers who had children before the reform
and those who had children after the change.

Increased fathersʼ take-up rate from 3 % in 1993
to 60 % in 1995. Fathers who took paternity
leave experience decline in earning.
Created substantial economic incentives for fathers
to be more involved in caring for their children
during their first months of life and the take-up
rate in the first year was 82.4%. Parents who areentitled to paternity leave are less likely to divorce
during the first ten years of their childʼs life,

Data: Norwegian registers, a difference-indifferences model that exploits differences infathersʼ exposure to the paternity-leave.
Register-based panel dataset comprising asample of 600 Icelandic families who had
children in the three months before and thethree months after the first change to theparental leave system. Difference-in-difference
model estimating the risk of divorce.

Benefit claims from the 2002-2010 rounds ofthe Employment Insurance Coverage Survey /for long-run effect, time diary data from
Canada's General Social Survey (GSS)

Respondents who had their last born child justafter the reform report an 11% lower level ofconflicts over a household division of labor andthat they are 50% more likely to equally divide
the task of washing clothes than respondents
who had their last child just before the reform.
(but this does not necessarily mean that men are
doing more of the housework.)

Data: 2007/2008 Life course, Generation and
Gender study (LOGG). Control group parents
with the last child born between April 1, 1991,
and March 30, 1993, vs. experiment group ofparents who had their last child born between
April 1, 1993, and March 30, 1995. Quasiexperimental

Leave reserved for fathers did increase fathersʼ
take-up; Fathers not only responded to higher
benefit but also the daddy-only label associatedwith quota. (Majority of families did not
exhaust leave benefit before the reform. Longterm effect was observed in the time-use patternthat showed an increase in the hours men spend
in unpaid work.

What are the results?

Data & Methods

Table 2 Table 1. List of articles on the effect of parental leave policies on fathersʼ involvement in childcare. (quasi-experimental designs)

並列均衡と交換経済
鷲田豊明
概要
一般均衡（General Equilibrium）は、今日の市場経済の本質的な機能を、価格による財・サービスの交換過程として表現する。また、このような過程が、パレート最適状態をもたらすという、
規範的な意味も示している。さらに、ゲーム論との関係のなかで、この一般均衡が、コアに含まれるという意味での頑健性、安定性を持っている蓋然性も示されている。
本論文では、市場経済を理解するためのツールとして、一般均衡とは少し異なる並列均衡（Parallel

Equilibrium）という概念を提起する。並列均衡とは、市場に参加する全ての主体が二者に分解され、その二者の間で並列的に進行する交換手続きを通して実現する均衡であり、均衡は全ての参加者にとってそれよりは望ましいものであり、規範的にはパレート最適性のみが約束される均衡である。この並列性のために、価格が機能していない。したがって、この均衡がコアに属することも約束されていない。並列均衡の中には一般均衡も含まれ、それに近い状態となることはあり得るが約束されるものではない。

Parallel Equilibrium and Exchange Economy
Toyoaki Washida
Abstract
General Equilibrium e presses essential functions of our market economies as processes of
e changes of goods and services. It also has the robustness and stability in the meanings that it
is included in core de ned by game theory. Moreover, it shows us the normative meanings thatit brings Pareto optimal states.
The paper proposes Parallel Equilibrium which is slightly di erent concept from the General
Equilibrium. The Parallel Equilibrium is reali ed by processes of all participants divided into
two subjects pair who e change each other. The equilibrium state is preferred to the initialstates for all participants and the state is Pareto optimum. The price is not unique so thatthe processes go on in parallel. Then it is not necessarily included in a core though it possibly
includes a General Equilibrium states.

95

並列均衡と交換経済
鷲田豊明

1

はじめに
均衡は、経済学の中心概念の一つで、複雑でダイナミックな経済を変化する契機がない状態として把握し、分析し、認識する手段である。経済学はそのために、多様な均衡概念を用いるが、一般
均衡（General Equilibrium）はその中でも最も重要な概念である。一般均衡は、今日の市場経済の本質的な機能を価格による財・サービスの交換過程として表現する。また、このような過程が、パレート最適状態をもたらすという、規範的な意味も示している。さらに、ゲーム論との関係のなかで、この一般均衡が、コアに含まれるという意味での頑健性、安定性を持っている蓋然性も示されている。
一般均衡が、市場経済の本質的側面をとらえていることは否定しがたい。が、それだけで市場経済の本質の全てが語られるものでないことも明らかである。丸山徹氏は一般均衡の前提となる「全ての主体にとって共通な市場が存在するという想定を外すとどうなるか？」と提起し、取引条件が一部の売り手と一部の買い手との間の交渉になり、その条件が相手が変わるごとに変わってしまい、「こうした、いわばバラバラに分解された経済では、市場の競争人の示す価格にあわせて、全主体が受動的に需給計画を決定すると言うがごとき、一種交響楽的なハーモニーは到底期待されそうにない。分断された経済の分析には、別の手法が開発されなければならない」（丸山、2013）と述べている。
本論文では、市場経済を理解するためのツールとして、一般均衡とは少し異なる並列均衡（Parallel

Equilibrium）という概念を提起する。並列均衡とは、市場に参加する全ての主体が二者に分解され、その二者の間で並列的に進行する交換手続きを通して実現する均衡であり、均衡は全ての参加者にとってそれよりは望ましいものであり、規範的にはパレート最適性のみが約束される均衡である。この並列性のために、価格が機能していない。したがって、この均衡がコアに属することも約束されていない。並列均衡の中には一般均衡も含まれ、それに近い状態となることはあり得るが約束されるものではない。
本論文は、このような並列均衡のワーキングの解明、および一般均衡が見落としてしまうような市場の機能を明らかにすることを目的としている。並列均衡そのものは一般性のある概念だが、ここでは一つの分析例として、並列均衡によって、市場の恩恵を受けるものと受けないもの、相対的に多くを手に入れる者とそうでない者との差の発生を分析する。一般均衡においては、交換の前後
で、どの主体にとっても価値は保存されているが、並列均衡は、その原始的性質から、また、価格という概念を持たないので、このような保存性が失われている。逆に、それによって、われわれの交換経済の本質に迫ることも可能になるのである。

2

並列均衡の定義とアルゴリズム
並列均衡は、その実現手続きとともに定義される。そのまえに、まず、交換から確認しておこう。

96定義 1：交換とは、それに参加する主体が、他の主体との財・サービスの授受によって自らを望ましい状態に変更しようとする行為である。
したがって、各主体は、自らの状態が改善していない限り交換に同意しないことを前提とする。
定義 2：並列均衡は、全ての主体を無作為に選択した二者の交換の繰り返しによって実現する均衡である。
二者の交換の繰り返しが、均衡にいたいるのか、すなわちそれ以上の状態の変更が、全ての主体
にとって受け入れられなくなるような状態に至るのか、その状態は、パレート最適性を実現するのか、これを理論的に明らかにすることは困難である。交換過程にさまざまな想定を組み込まない
限り、理論分析の対称とはなり得ない。ここでは、アルゴリズムを定義し、それによるシミュレー
ションによって均衡の可能性と特性を把握する。
まず、二者の交換の交換手続きをエッジワースのボックス図で示そう（図 1）。
x 2A
OB

x 1B
S
P
T

M

R
Q
L

x 1A

OA

x 2B

図 1: Gradient and E change

二人をとで表そう。交換前の状態がであったとしよう。

はA
からみれば xA
1 x2 でBからみれば xB
1 x2 であるとする。このとき、 点において、効用を増加させる方向へ−−の gradient ベクトルと R は、それぞれの効用関数を A および B として、

あり、

−

A

A

xA
1

xA
2

および、

−

R

B

B

xB
1

xB
2

となる。
交換は、その結果として両者が望ましい状態にならなければならない。それは、この場合、 から、無差別曲線で囲まれたレンズの内側への移動によって実現する。無数の選択肢はあるが、ここ−は、 からみると、では 方向への財の所持量の組み合わせの変更を考慮しよう。このとき、

97

−

−

となり、

−

−

−

A

R

xA
1

B

A

−

xB
1

xA
2

B

A

B

−

xA
1

−

xB
2

xB
2

−

xA
2

−

で与えるとして、実際どれだけの規模で交換するかからみると、

−

R−

B

−

xB
1

交換の方向性、すなわち交換比率は上記のAは別に定義されるべきである。この規模を決定するパラメータは、共通にしよう。このとして与えることには、ある程度小さくなければならない。なぜなら、大きすぎると、パレート最適点を外してしまうからである。
−−
および R の長さ（絶対値）に注目すべきである。二人の状態がともに改善するこ
また、−とは、それぞれの長さが不適切だと実現できない。両者の長さが等しいと、その和のベクトル
は、両者の効用を厳密に改善する方向となる。すなわち、

−

−

R

であることが必要となる1 。
したがって、一回の交換によって実現する

−−−−−

A new

同じく、

−

−

new

−−B−

−

R−

となる。

−

−

の新たな所持量new は、

R

の所持量は

−−−−−
B

−−A
−

いまもし、交換前の状態が図の−−点のように表されると、実質的な交換は行なわれない。 R −0（零ベクトル）となってしまっているからである。この状態はまた、限界代替率が等しい状態である。
われわれのアルゴリズムはすべての参加者の間で、すべての財に関して限界代替率等しくなって−−R−いるときに、手続きは止まるようになっていなければならない。実際の計算では、このの絶対値（ノルム）がある正の十分小さな値以下になっている状態で計算を止めるように設計されるべきである。
アルゴリズムは、図 2 に表している。
したがって、このすべての限界代替率が等しくなっている状態は、また、パレート最適でもある。並列計算アルゴリズムは、正常に収束する場合には、パレート最適点に収束していることになる。また、それが初期状態（アルゴリズム開始の時点）より望ましい状態であることは、十分確かに推定される。

並列均衡のシミュレーション

3

この並列均衡アルゴリズムが実際にパレート最適点に収束することを、いくつかのシミュレー
ションで示しておこう。純粋交換経済を考える。主体の数を数をiとし、財の数を M とする。効用関とし、次のように特定化する

1 ただし、本論文における実際のシミュレーションでは、収束を高速化させるために、これにこだわらずにベクトルを定める。結果的に、並列均衡においては、両者の効用が改善されることと、パレート最適性が実現されれば良いからである。

98

図 2: Parallel Equilibrium Algorism

M
�

i

i
i
j ln xj

j=1

ここで

i
i
j が特定化され、また、xj の初期状態があれば、このアルゴリズムを実際にシミュレー

ションすることができる。
今回は、表 1 のような設定で行った。収束基準を 5.0e-8 にしているが、1.0e-9 程度でも十分収束する。
表 1: Parameters and Initial Endowmentsij rangeij basexij range

xij base

i

0.5

0.2

10.0

1.0

0.01

tolerance
2.0e-81.0e-9は、各主体 、各財 に関して、まず、base となる値を与え、range の範囲内の無作為に実数を加えて設定した。同じく、初期賦存量 xij についても、base を与えた上で、range の範囲内の実数を無作為に加えて設定した。ただし、初期分配の所得は、すべての財の価格を 1 と想定した上で、すべての人について財数と同じになるように調整する。すなわち、各主体が一つの財を平均 1ずつ持つように設定している。したがって、各自の初期賦存量の財の割合は、総保持量（総所得）がすべての人にわたって等しくなるような形で、無作為にばらついた値となっているのである。
交換主体と財の数を、 1 10 人 10 財、 2 100 人 100 財、 3 1,000 人 1,024 財、 4 10,000 人

1,024 財、 5 300,000 人 1,024 財の 5 パターンで行なった。計算には、並列計算アルゴリズムと並列計算コンピュータを用いたが、そのスレッド数の制約から、財の数は 1,024 財が上限となり、メ99

モリ制約から最大主体数が 300,000 人となっている2 。
シミュレーションの結果を表 2 にまとめた。
表 2: Simulation Results

persons goods iteration time sec.
10
10
5,796
1

nal di s mrs di ma
5.08e-10
2.03e-6

mrs di min mrs di ave
2.43e-93.00e-7100

100

28,2193

1.82e-8

1.62e-6

0.0e-12

1.11e-8

1,000

1,024

9,104

4

9.73e-102.64e-90.0e-120.3e-11

10,000 1,024
300,000 1,024

9,317
9,472

40
2,364

9.83e-10
9.88e-10

2.40e-93.17e-90.0e-120.0e-120.1e-110.0e-12

まず、シミュレーションでは、並列計算アルゴリズムとマルチコアのハードウェア3 を用いているので、計算速度はきわめて速い4 。30 万人が 1,024 個の財を交換する状況でも、最適解を約 40 分
で解いている5 。

nal di s は、最終的な各財の gradient の差の最大値であり、それが tolerance 以下になっていることを示している。ほぼゼロである。mrs は第 0 材に対する限界代替率を表し、すべての人、す
べての財にわたって計算し、対応する限界代替率の差の割合の最大値、最小値、平均値を表している。比較的、人と財の数が少ない場合に、大きな値となっている。たとえば、10 人 10 財の場合、最大の限界代替率の差は 0.0002 であり、それでもほとんどさがないと言ってよい。他の場合は、
ほぼ限界代替率に差はないことを表す値となっている。すなわち、すべての人の間で、二つの財の限界代替率は等しくなっているのである。すなわち、シミュレーションの結果において、すべての並列均衡は、パレート最適である。
また、すべてのシミュレーションにおいて、すべての主体が、初期状態からみて効用を厳密に増加させていることも確認している。

4

並列均衡の意味
並列均衡が、すべての参加者によって初期状態よりも望ましくまたパレート最適であるという規範性を持ちうることを示したので、改めて並列均衡の意味を考えてみよう。
並列均衡は、パレート最適であるために、パレート基準で、一般均衡よりも劣った均衡であるとは言えない。ただし、コアには含まれていない可能性があるので、ゲーム論的な意味での、安定性の点では、粗野な均衡であることは否めない。
一般均衡と本質的に異なるのは、価格が機能していないことである。純粋交換の一般均衡においても、最終状態において限界代替率はすべて等しくなっているが、それは同時に価格比でもある。
しかも、その価格で計ると、最終状態の財全体の価値は、初期状態の総価値に一致している（自由財がなければ）。並列均衡においても、一般均衡と同様に限界代替率はすべての主体にとって等し
いので、それを価格と見なすことはできるが、その価格で計った初期状態の価値は、必ずしも最終
2 並列計算アルゴリズムと、ハードウェアの詳細は別に述べる。
3 Tesla K20, 2,496 cores.

4 たとえば、500 人 100 財の純粋交換均衡の場合、非線形連立方程式解を求める GAMS を用いると 10 時間以上かかった。
5 この計算時間のかなりの割合が、無作為に 2 者の組み合わせを決めているプロセスで費やされていることを指摘しておこう。実際に、並列的な交換プロセスの計算は、半分以下の時間しかかかっていないと思われる。

100

状態の価値に一致しない。すなわち、最終状態における財の総価値からみれば、初期状態から豊かになった人も貧しくなった人もいるのである。しかし、価格がないので、そのような結果は明示的には見えてこない。
並列均衡において、価格が役割を果たしていないという事実は、この均衡の完全な非現実性を表していると言えるだろうか？ 市場経済において、価格の成立していない市場はないように見える。並列均衡においては、交換が完全に分解されてしまっているので、分解された個々の交換において、交換比率は発生するが、その交換比率は、交換が現実に行なわれているプロセスでは、他の場で行なわれている同じ財の交換比率とは異なってしまっている可能性がある。すなわち、「一物一価の法則」は全く成立しない。
確かに、同じ市場の同じ場所にある特定の財に二つの価格がつくことは理論的にも現実的にもあり得ないだろう。しかし、財やサービスが、そのおかれた条件の違い以上に、異なった価格をつけているように見える事態は、それほどまれではない。市場で、主体の交渉力などによって価格がかわってくることは日常的にあり得る。価格よりも、交換が優先されることは現実に発生する事態なのである。その交渉力の対象になっているものが同じ財ではないと言えるかもしれない。たとえば、A さんの持っている G という財と B さんの持っている同じ G という財は、財だけみれば同じだけれども、市場では異なった財と見なすということは、漕艇場はあり得るかもしれない。あるいは、賃金は労働につけられた価格であるが、それは同じ労働時間でも、無数に近いバリエーションを持っている。経済学は、このような財やサービスにつけられる多様な価格を単に捨象しているのにすぎない。
すなわち、現実の経済に均衡があるとしたら、それは並列均衡と一般均衡という二つの性質を持っていると考えた方がよいということである。あるいは、現実の経済の均衡は、並列均衡と一般均衡の中間にあると言ってもよい。
また、財の流通ということを考えてみてもよい。ある主体から、別の主体に、財が次から次へと持ち手を帰ることによって流通は成り立っている。このようなプロセスとその結果は、並列均衡のアルゴリズムそのものに似ている。

5

並列均衡から見える市場
並列均衡は、一般均衡とは異なった視点からわれわれの市場経済を分析するツールとなる。
ここでは、一つの例を示そう。先に述べたように、一般均衡においては、初期値の総価値と交換

後の総価値は基本的に等しい。これは、ある与えられた価格のもとで全体一斉に交換が行なわれることを前提にしているからである。しかし、並列均衡においてはこのようなことが成立しない。すべての主体は初期状態よりも満足しているのだが、交換の結果には完全に平等ではない状況が現れる。交換前は、先に述べたように、すべての財の価値を 1 として、財の数だけの共通の所得で財が配分されている。財の配分そのものはランダムだが、その合計はすべての主体で等しくなっているのである。交換後の状態は、すべての財の価格を 1 としても、あるいは、限界代替率を用いても計ることはできる。いま、すでに示したシミュレーション結果でこれがどのようになっているのかを示すと、図 3 のようになる。
この図は、縦軸がその所得の人数であり、横軸が所得である。所得 1 単位ごとのヒストグラムになっている。ただし、価格がすべて 1 として、最終状態の所得の分布を示したものである。価格を最終的な限界代替率に変えても、分布はほとんど重なるので、そちらは示していない。この場合、初期の所得は、1,024 に統一しているので、きわめて公平な状態から出発して、図のような分布が101

14000
12000
10000
8000
6000
4000
2000
0

960

980

1000

1020

1040

1060

1080

図 3: Income Distribution 30,0000 subjects

発生したことになる。最大所得は、1,071 で、最小は 976 である。これを大きいとみるか、小さいとみるかはこれだけでは判断しがたいが、完全に等しくなる一般均衡との差は歴然としている。
このように所得の分布が発生することは、単に、並列均衡の粗野な性質からくるものと考えるべきではない。先にも述べたように、並列均衡は現実の一部を反映しているのであり、したがって、このような所得の分布もまた、交換経済の帰結と考えるべきである。遺産などの外的なものをのぞけば、われわれはただ、自分の持っている物を交換しているだけである。しかし、実際に貧富の差は発生する。労働は単一のサービスではなく、多様な質を持った多様なサービスと考えるべきである。それらの交換の結果としてあるものは豊かになり、貧しくなると言える。
この所得分布では、全てが 1 である初期の価値と最終的な限界代替率で測った価値で評価した所
得分布がほとんど重なっていたが、少し違った場合も示しておこう。図 4 は、主体が 300,000 人、財が 1024 の場合における、その両者の分布を 1 単位ごとのヒストグラムで示している。ここでは、初期の分配パラメータの base 値を最初の第 1 財から最後の第 1024 財まで、0.02 ずつ増加させ

6ている 。したがって、財の需要に偏りが発生することになる。
シミュレーションは、117,021 回で収束し、8 時間 5 分 14 秒かかっている。そうしない場合よりも、格段に必要繰り返し回数、および時間が増えている。全ての主体が最終的に初期状態より厚生水準を厳密に増加させ、最終誤差は 9.35e-10 で、最終限界代替率の違いの最大値は 2.82e-9 で、最小値、平均値はそれぞれほぼ 0 である。したがって、最終状態がパレート最適であることはほぼ確実である。
図 4 をみると、この場合は、初期の単位価値で最終所得を評価すると、分布は、ほぼ初期配分の1,024 の近くに固まってしまっているが、限界代替率で評価した所得は、このような偏りを入れていない場合と同様な分布を見せている。

6 実際さらに、総和が、そうしない場合と同じ時なるように正規化しているが、理論的にはこれはしてもしなくても結果は同じになる。

102

90000

20000

80000

18000

70000
60000

Unit Prices

16000

Mrs Prices

14000
12000

50000

10000

40000

8000

30000

6000

20000

4000

10000
0

2000
960

980

1000

1020

1040

0
1080

1060

図 4: Income Distribution 30,0000 subjects with MRS

6生産を含む並列均衡

6.1

生産と交換

これまでのモデルの中には、消費者だけが存在した。消費者はそれぞれ、初期に財のバスケットを保有していて、交換をすることによってそのバスケとの財の組み合わせをより望ましいものに変更する。この交換の繰り返しによって、すべての主体がそれ以上の交換を望めない状態、それが並列均衡となった。ここで、生産をモデルの中に組み込もう。生産とは、通常は、生産要素を投入し、何らかの財を新たに生み出すアクティビティと経済学では考えられてきた。そこには、生産を、新たな財が創造されるプロセスに注目していた訳である。このプロセスを担っているのは一般に企業と呼ばれるが、この企業も、対外的には単に交換を行っているだけであり、交換によって状態を変えようとしているという点では、消費者と同じである。ここでは、まず、こうした生産の担い手である企業を、交換主体として定義する必要がある。
また、並列均衡においては、価格というものを明示的に表さない。通常、企業の利潤最大化行動
なり、費用最小化行動は価格を用いなければ定義できない。この問題も同時に解決しなければならない。
いま、最も単純な形で、生産を含む均衡を考えよう。二人の消費者と企業が一つあったとする。
財は、2 種類のみで、一つの企業がこの二つの財を結合生産している。既に生産要素は企業に与えられていて、企業はただ、この二つの財の生産フロンティア上で二つの財の生産量の組み合わせだ
けを技術的に調整できるだけだとしよう。図 5 にこの状況が描かれている。消費者二人の状況は、
初期分配をのぞけば図 1 に描かれたものと基本的に同じである。企業は、原点F で表される生産フロンティアを持っている。いま、このフロンティア上の一点て選択されたとする。そして、この企業の所有権を A および B がAM :A からみて、曲線
B が企業によっ

B M の割合で持っていて、その割合に応じて二つの生産物が二人の消費者に分配されたとすると、二人の消費者の初期

103

図 5: Parallel Equilibrium and Production

保有量は M 点となる。
この M 点は、なによりも二人の消費者の間の限界代替率が等しくないので、二人の間で交換が行われ、最終的に領域 R の中のある一点で、限界代替率が等しくなるようなところが選ばれる。しかし、もし、この最終的な限界代替率が、もともとの生産フロンティア上の限界変形率と等しくない場合は、もともとの生産フロンティア上の点を別な点に変更することによって、パレート優位な最終結果を得ることができる。たとえば、いま、両消費者の間で等しい限界代替率を �x2 /�x1 であり、限界変形率が �x�2 /�x�1 であったとしよう。そして、さらに、

�x2
�x�2
<
�x1
�x�1
となっているとしよう。このとき、消費者にとっては、第 1 財を微小に 1 単位だけ減じ第 2 財を

�x2 /�x1 単位増加させても、両者の効用水準は変わらない。一方、第 1 財の生産を 1 単位減じると、第 2 財の生産を �x�2 /�x�1 だけ増やすことができる。そうすると、�x�2 /�x�1 − �x2 /�x1 > 0だけ、両消費者の満足度を維持したまま、余剰を発生させることができる。これを両方、あるいは、どちらかの消費者に配分すれば、誰の満足度を下げることなく、いずれか一方、あるいは両方の満足度を増加させることができることになり、そのような状態はパレート最適ではないことを意味する。したがって、パレート最適であるためには、限界代替率と限界変形率のすべてが等しくなっていなければならないのである。
このような状況の中に、生産を含む並列均衡の基本的な形が描かれている。価格が明示的な役割を果たす必要がなく、消費者も生産者も相互の分離された交換と、限界代替率ないしは限界変形率だけが問題になる状況となっている。

104

6.2

生産の概念

ここで、改めて並列均衡と整合性を確保できるような生産概念を考えてみよう。企業は消費者との間で財と貨幣を交換する。貨幣は価値基準財にすぎないとすれば、これは消費者と企業の間での財の交換と解釈できる。また、消費者は労働の提供者であるとすれば、労働と財の交換だといえる。

7

並列均衡のアルゴリズム
ここでは、通常の直接的計算と対比させる形で、並列均衡計算のアルゴリズムのコアの部分を示しておこう。交換主体が 20,000 人、財が 1,024 種類あるとする。
まず、従来の直列的計算法を示す。計算用のコア（CP ）が一個であるとする。先に示したア
ルゴリズムを通常の計算手続きで実現すると、図 6 のように基本的にループ計算を用いる。まず、無作為に 2 人のペアが 10,000 ペア作成される。次に、ペアの一つを取り上げて、1,024 個の財について、1 個ずつ、gradient（一種の相対価値）を計算し、ペアの両者の差から、その財についての交換量を計算する。これが一番内側のループ Loop 1 である。次に、これをすべての人について、一人ずつ 10,000 回行なう。Loop 2 である。ここだけで一つの CPを利用して 1,024 万回の計算が行なわれる訳である。

Making pares

Loop 0

Gradient Calculation

Loop 1
1,024

Exchange

Check convergence

図 6: Series Calculation

105

Loop 2
10,000Making pares

1

2

1

3

Goods
4

1,024

2
Loop

3
Pares of
Persons
10,000

Check convergence

図 7: Parallel Calculation

この課程の最大交換量を誤差として、収束を判定する。交換量が十分少なくなっていれば、それがパレート最適状態である。誤差がまだ大きいと、一番外側の Loop 0 がおこなわれる。
以上が、従来の直列的計算のアルゴリズムである。
これに対して、並列計算は、多数のコアを利用して、並列的に計算を行なう。図 7 に計算のアルゴリズムを示す。直列の場合の、Loop 1 および Loop 2 は存在しない。まず、ペアが 10,000 個造られる。これは同じである。このペアと、財をマトリクスのように指定されたセルについて、一つのスレッドが割り当てられる。たとえば、図の色の濃いセルは、第 3 番目のペアの、第 2 番目の財について割り当てられたスレッドである。ここで、gradient の計算、およびその財についての交換の計算が行なわれてしまう。すなわち、1,024 万個のスレッドが作成され、システムによって多数のコアに自動的に割り当てられるのである。ここでの計算の場合は、2,496 個のコアに 1,024 万個
スレッドが割り当てられる訳である。

参考文献[1] 丸山徹, 2013,『新講 経済原論 第三版』, 岩波書店.
[2] Debrew, Gerard, Herbert Scarf, 1963, “A Limit Theorem on the Core of an Economy”,
International Economic Review, Vol.4, No.3, pp.235–246[3] Johansen, Lief, 2012, “A Calculus Approach to the Theory of the Core of an E change
Economy”, The American Economic Review, Vol.68, No.5, pp.813–820[4] Schwei er, rs, 1982, “A Lagrangean Approach to the Limit Theorem on the Core of an
Economy”, Zeitschrift fur Nationalokonomie Journal of Economics, Vol.42, No.1, pp.23–30

106[5] Green, Jerry R., 1972, “On the Inequitable Nature of Core Allocations”, Journal of Economic Theory 4, pp.132–143[6] 鈴木康夫, 1995,『コア極限理論へのラグジュアン解析的接近法についての解説』, 神戸学院経済学論集, pp.75–91[7] Qin, Cheng-Zhong, Lloyd S Shapley, Ken-Ichi Shimomura, 2006, “The Walras core of an
economy and its limit theorem” Journal of Mathematical Economics 42, pp.180–197[8] Aumann, Robert J., 1964, “Markets with a Continuum of Traders”, Econometrica, Vol.32,
No.1-2, pp.39–50[9] Schotter, Andrew, 1973, “Core Allocations and Competitive Equilibrium—A Survey”,
Zeitschrift fur Nationalokonomie 33, pp.281–313[10] Dierker, Hildegard, 1975, “Equilibria and Core of Large Economies”, Journal of Mathematical Economics 2, pp.155–169[11] Bewley, Truman F., 1973, “Edgeworth’s Conjectrure”, Econometrica, Vol.41, No.3, pp.425–
454[12] Arrow, Kenneth J., 2012, “General Economic Equilibrium: Purpose, Analytic Techniques,Collective Choice”, The American Economic Review, Vol.64, No.3, pp.253–271

107

上智地球環境学会

1 . 設立主旨
持続可能 地球社会形成、社会科学、人文科学

地球環境学 創成 発展 必要性 今日誰 目
貢献

研究者 知的研究 人材育成
互依存、琢磨明

展開 目的
新。上智地球環境学会 、

人的
発足

形成

。自由

文明創造的 場 広 提供

自然科学 成果 総合(3)。

(2) 研究紀要『地球環境学』 発行
発行

(4)

他

3 . 構成(1) 地球環境学研究科

専任教員(2) 地球環境学研究科、

議論、自立的 研究 相

2 . 学会 活動(1) 定例研究会 開催

基礎

大学院生

地球環境学No. 142019 年 3 月 26 日 発行

発行

上智地球環境学会〒 102 - 8554
東京都千代田区紀尾井町 7 - 1

Tel. 03 - 3238 - 4366 Fax. 03 - 3238 - 4439
上智大学大学院 地球環境学研究科
URL: http://www.genv.sophia.ac.jp

印

刷

所

株式会社 白峰社

ISSN

1880 - 7143