平成 24 年度
東北地方太平洋沿岸地域
自然環境調査等業務報

告書

平成 25（2013）年 3 月

環境省自然環境局生物多様性センター

- 目

次 -

１．業務概要 ································································· 1-1
1.

業務概要 ··································································· 1-1

1.1

業務の目的 ······························································ 1-1

1.2

実施期間 ································································ 1-11.3

業務対象範囲 ···························································· 1-1

1.4

業務内容 ································································ 1-2

2.

業務工程表 ································································· 1-4

3.

実施体制 ··································································· 1-54.

成果品 ····································································· 1-5

２．海岸調査 ································································· 2-1
1.

砂浜・泥浜の変化状況 ······················································· 2-11.1

調査対象海岸 ···························································· 2-11.2

調査対象海岸の概要 ······················································ 2-21.3 東日本大震災による沿岸域への影響 ········································ 2-71.4

資料収集・整理 ························································· 2-18

1.5

調査方法 ······························································· 2-201.6 砂浜・泥浜海岸変化要因の考察方法 ······································· 2-272.

砂浜・泥浜の変化状況の調査結果 ············································ 2-362.1

調査対象海岸 ··························································· 2-362.2 各道府県における土地被覆別の面積変化 ··································· 2-392.3

変化要因別の傾向 ······················································· 2-45

2.4

土地被覆面積変化の相互関係 ············································· 2-52

2.5

県毎の変化状況 ························································· 2-55

3.

海岸線改変調査 ··························································· 2-110
3.1 概要 ·································································· 2-110
3.2

調査方法 ······························································ 2-112

3.3

調査結果 ······························································ 2-117

３．旧版地図の読図 ··························································· 3-1
1.

調査概要 ··································································· 3-1

1.1 目的 ···································································· 3-1
1.22.

調査内容 ································································ 3-3

調査結果 ··································································· 3-72.1

地形の特徴 ······························································ 3-7

2.2

地名との関連 ··························································· 3-15

2.3

まとめ ································································· 3-16

４．植生調査 ································································· 4-1
1.

調査概要 ··································································· 4-12.

植生改変図作成調査 ························································· 4-22.1

調査方針 ································································ 4-22.2

調査範囲 ································································ 4-22.3

調査方法 ································································ 4-32.4

調査結果 ······························································· 4-20

3.

重点地区調査 ······························································ 4-47
3.1 目的 ··································································· 4-47
3.2

調査範囲 ······························································· 4-473.3

調査方法 ······························································· 4-49

3.4 結果 ··································································· 4-50
4.

解析・とりまとめ ·························································· 4-63

4.1

GIS データの作成 ························································ 4-634.2

面積集計 ······························································· 4-63

4.3 地震等による植生への影響（津波高および地盤高との関係把握）·············· 4-68
4.4

カルテの作成 ··························································· 4-71

５．藻場関連調査の情報収集 ··················································· 5-1
1.

業務内容 ··································································· 5-1

1.1 概要 ···································································· 5-11.2

資料収集 ································································ 5-1

2. GIS データ作成 ······························································ 5-3
2.1

収集資料の内容 ·························································· 5-32.2

GIS データ作成方法 ······················································· 5-62.3

GIS データ作成結果 ······················································ 5-10６．生態系監視調査 ··························································· 6-1
1.

調査の背景と目的 ··························································· 6-1

2.

調査の概要 ································································· 6-22.1

調査対象サイト ·························································· 6-22.2

調査体制及び調査実施状況 ················································ 6-53.

調査方法 ··································································· 6-73.1

干潟調査 ································································ 6-73.2

アマモ場調査 ···························································· 6-9

3.3

藻場調査 ······························································· 6-133.4

海鳥繁殖地調査 ························································· 6-154. 結果 ······································································ 6-174.1

干潟調査 ······························································· 6-174.2

アマモ場調査 ·························································· 6-138

4.3

藻場調査 ······························································ 6-1664.4海鳥繁殖地調査 ························································ 6-178

5. 考察 ····································································· 6-211
5.1 干潟 ·································································· 6-212
5.2

アマモ場・藻場 ························································ 6-2155.3海鳥繁殖地 ···························································· 6-217

７．対象地域における調査等の情報収集 ········································· 7-1
1.

目的および背景 ····························································· 7-1

2.

収集方法 ··································································· 7-12.1

収集対象 ································································ 7-1

2.2

情報収集の手法及び情報収集先 ············································ 7-1

2.3

収集結果 ································································ 7-3

８．業務成果の公開 ··························································· 8-1
1.

業務成果の公開について ····················································· 8-1

2.

公開用データの作成 ························································· 8-2
2.1

公開用データの一覧 ······················································ 8-2

2.2 データの作成方法および閲覧性を向上させるための工夫 ······················ 8-3

９．有識者ヒアリング ························································· 9-1
1. 目的 ······································································· 9-1
2.

対象とした有識者一覧 ······················································· 9-1

3.

ヒアリング結果 ····························································· 9-2

１０．地震等による自然環境への影響に関する検討 ······························ 10-1
1.

検討会の実施 ······························································ 10-1
1.1 目的 ··································································· 10-1

2.

1.2

検討委員一覧 ··························································· 10-1

1.3

実施状況 ······························································· 10-21.4

検討内容 ······························································· 10-3

今後のモニタリング計画 ··················································· 10-10

１１．総括 ·································································· 11-1
1.

はじめに ·································································· 11-1

2.

調査結果 ·································································· 11-13.

2.1

海岸調査 ······························································· 11-1

2.2

旧版地図の判読 ························································· 11-22.3

植生調査 ······························································· 11-22.4

生態系監視調査 ························································· 11-32.5

自然環境に関する情報収集 ··············································· 11-32.6

情報公開 ······························································· 11-32.7

検討会 ································································· 11-4

今後の取組み ······························································ 11-4

＜資料編＞
資料１

海岸調査

地区海岸一覧

資料２

植生調査

震災前植生図資料３

植生調査

震災後植生図

資料４

植生調査

植生改変図

資料５

植生調査

面積集計結果

資料６

生態系監視調査

調査マニュアル

資料７

生態系監視調査

データシート

資料８

ヒアリング記録一覧

資料９

平成 24 年度東北地方太平洋沿岸地域自然環境調査等に関する検討会資料

平成 24 年度東北地方太平洋沿岸地域自然環境調査等業務
要 約１．業務目的
2011 年３月 11 日に発生した東北地方太平洋沖地震及びそれに伴う津波（以降、東日本大震災という）は、東北地方太平洋沿岸を中心とする地域の自然環境、生活環境、社会環境に極めて大きな影響を与えた。本業務は、東日本大震災による自然環境への影響が特に顕著であった東北地方太平洋沿岸地域等において、植生、海岸等の調査を行うとともに、地震等による自然環境等への影響を整理・把握することで、今後の継続的なモニタリング等の効果的な施策につなげることを目的とした。
なお、本業務はアジア航測株式会社（共同実施者：一般財団法人自然環境研究センター）が実施した。
２．結果概要(1) 海岸調査
調査対象域（津波浸水域）の泥浜・砂浜（調査延長約 510km）を対象に、1970 年代（高度経済成長期）、震災前、震災後の３時期の空中写真、衛星画像等を判読し、沿岸の土地被覆の変化を縮尺1/10,000 で整理、GIS 化した。解析により、個別の海岸の変化を把握するとともに、青森、三陸北、三陸南、仙台湾、福島、茨城・千葉の６つの地域ゾーンごとの沿岸の自然環境の変化（汀線、海岸林、砂浜等の状況）を明らかにした。
(2) 旧版地図の判読
明治後期〜大正前期の旧版地図（縮尺 1/50,000）を、土地分類基本調査（地形分類図）を参考として、「旧河道」、「河川」、「湖沼」、「湿地」、「砂丘」、「砂浜」の凡例で判読し、GIS 化した。判読結果を震災後の浸水域の状況等と比較することで、かつての地形や土地利用が、現在の自然環境の姿を読み解く材料として有効であると考えられた。
(3) 植生調査
津波浸水域の震災前後の植生図の作成、植生図作成のための組成調査、震災の時点情報として広く植生の相観を把握する植生景観調査、特定植物群落調査等を行った。震災前後の植生図は、沿岸部は縮尺 1/10,000、内陸部は 1/25,000 で判読図化した。震災後植生図には従来の凡例に加え震災による被災状況を示す凡例（樹林では倒伏、立枯れ等）を付加した。また、2 時期の植生図の差分を植生改変図として整理し、いずれも GIS データ化した。集計解析により、海岸林、砂丘植生等の重要な自然資源の消失・劣化、海岸林への外来種木本群落の侵入等を整理した。また、(1)海岸調査同様、6 つの地域ゾーンごとの植生への影響パターンを整理した。このほか、3 箇所の重点調査地区で、地形、植生、動物の一体的な調査を試行した。
(4) 藻場関連調査の情報収集
青森県〜千葉県の太平洋沿岸における藻場分布情報に関する既存資料の情報（6 件）の整理と GISデータ化を行った。
(5) 生態系監視調査
津波浸水域等に含まれる第７回自然環境保全基礎調査及びモニタリングサイト 1000 の調査実施地
点のうち、干潟（15 箇所）、アマモ場（５箇所）、藻場（４箇所）、海鳥繁殖地（３箇所）で震災後の調査を実施し、震災前後の比較を行った。この結果、地形等の立地特性と津波、地盤沈下の外力の大きさの違いによると考えられる様々な影響形態を調査地点ごとに整理した。
(6) 自然環境に関する情報収集・情報発信、有識者ヒアリング
津波浸水域に関する震災前後の自然環境に関する調査、研究等の情報を幅広く収集し、スクリーニングの結果 104 の重要情報に集約した。これらの既存情報及び(1)、(3)に関する情報を、国民の利活用を図るため、情報の収集・提供を行っている者に対し、震災に関する効果的な情報発信を行
うための助言等を得て、ウェブサイト「東北地方太平洋沿岸地域自然環境情報」（http://www.biodic.go.jp/Tohoku̲Portal/）より順次発信した。
(7) 検討会
2013 年２月８日、仙台市において検討会を開催し、平成 24 年度に実施した各調査の結果を報告するとともに、今後の効果的な調査計画や情報の効果的な利活用のあり方について審議いただき、陸と海をまたいだモニタリングを行うべき、復興に活かすための調査成果の発信を検討するべきなどの意見をいただいた。

2012 Survey of the Natural Environment in the Pacific coast of Tohoku district
Summary
1. Objectives
The 2011 off the Pacific coast of Tohoku Earthquake and Tsunami brought tremendous effects onnatural, social and living environment. In this project, changes in vegetation distribution and coast are
surveyed in the disaster area in order to organize and to understand the effects of the earthquake to thenatural environment, moreover, to connect to the effective policies such as continuous monitoring of thenatural environment in the Pacific coast of Tohoku for the future. The survey was conducted by Asia Air
Survey Co.,Ltd (Joint implementation with Japan Wildlife Research Center).

2. Overviews of the results(1)Coast Survey
Coast survey on changes in sandy/muddy beaches (extend to 510km total) was conducted in theproject area (Tsunami flooded area). The land use changes among 1970s, 2000s and 2011(after theearthquake) were interpreted by using satellite imageries and aerial photographs. Those changes weredigitized and processed as GIS data in 1:10,000 scale. By analyzing the data, the changes in individual
coasts were understood and overall changes in natural environment (shoreline, coastal forest andbeaches) were clarified in 6 coastal zones (Aomori, north Sanriku, south Sanriku, Sendai bay, Fukushimaand Ibaraki-Chiba).

(2)Interpretation of Old Edition Maps
By interpretating the Old Edition Maps of late Meiji to early Taisho era (1:50,000 scale), rivers, lakes,wetlands, sand dunes and beaches were identified and digitized as GIS data. This data is considered as
effective material to understand the present natural environment after the earthquake disaster.

(3)Vegetation Survey
Vegetation mapping, vegetation survey, vegetative landscape survey and specific plant community
survey were conducted. The vegetation maps before and after the earthquake were created in scale
1:10,000 in coastal area and in scale 1:25,000 in inland area. Classification relating disaster damage suchas ‘lodging’ and ‘die back’ were added to forest classification. Vegetation change maps were made byoverlaying those two maps and digitized as GIS data. By analyzing the difference of the maps, changes in
the natural environment; degradation of important natural resources such as sand dune vegetation andcoastal forest and invasion of alien species to coastal forest were identified. Also, similar to (1)Coastsurvey, the patterns of the earthquake effects to vegetation in 6 zones were specified. In addition,
topography, vegetation and fauna were surveyed in three pilot areas as selectively area survey.

(4)Seaweed beds data collection
The seaweed beds data of 6 area in the pacific coast from Aomori to Chiba prefecture was collected
and digitized as GIS data.

(5)Ecosystem monitoring survey
Survey sites of tidal flats (15 sites), zostera bed (5 sites), seaweed beds (4 sites) and seabirds (3sites)
were selected from the sites of the 7th National Survey on the Natural Environment and Monitoring Sites
1000 (all survey sites above are in the tsunami flooded area). By comparing the result of the survey after
the earthquake to the one of the previous survey, effects of the earthquake depending on the factors suchas characteristics of location, difference of external force of tsunami and ground subsidence wereunderstood.

(6)Data collection and information release/academic adviser interviews
The survey and research data relating natural environment in tsunami flooded area was widelycollected and screened to 104 important sources. In order to promote wide and effective use of these
existing information and the results of (1) and (3) above, with the advices from 5 academic professionals
who have been collecting and providing the information on the disaster, data is opened on the website ‘theNatural environmental information in the Pacific coast of Tohoku district’ (http://www.biodic.go.jp/Tohoku_Portal/)(7)Advisory committee meeting
The Advisory committee meeting was held on February 8th, 2013 in Sendai to report the results of thesurveys conducted in the fiscal year 2012. The effective survey plans and the ways to utilize data arediscussed. It was suggested to conduct monitoring crossing from sea to land and to share the results ofthe surveys for recovery from the disaster.