FRONTIERS 2018/19
Emerging Issues of Environmental Concern

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© 2019 United Nations Environment Programme
ISBN: 978-92-807-3737-0
Job No: DEW/2221/NA
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FRONTIERS 2018/19
Emerging Issues of Environmental Concern

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© Johnny Adolphson / Shutterstock.com

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Foreword

7

Acknowledgements

8

Synthetic Biology: Re-engineering the Environment
Opportunities and challenges
Rewriting the code of life
Applications redefined: From laboratory to ecosystem
Innovating with wisdom
References

10
10
12
16
18
20

Ecological Connectivity: A Bridge to Preserving Biodiversity
Reconnecting fragmented ecosystems
The forces of fragmentation
Promoting connectivity solutions
Setting targets for future connectivity
References

24
24
26
30
32
34

Permafrost Peatlands: Losing Ground in a Warming World
Accelerating change in the Arctic
Thawing permafrost, decaying peat and complex interplays
Growing awareness of permafrost peatlands
Knowledge priorities and network expansion
References

38
38
40
44
46
48

The Nitrogen Fix: From Nitrogen Cycle Pollution to Nitrogen Circular Economy
The global nitrogen challenge
The knowns and known-unknowns of nitrogen
Policy fragmentation and circular economy solutions
Towards a holistic international approach for nitrogen
References

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60
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Maladaptation to Climate Change: Avoiding Pitfalls on the Evolvability Pathway
Defining adaptation and maladaptation for the climate change context
Maladaptation at scale
Avoiding maladaptation in a 1.5°C constrained future
References

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UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Table of contents

5

6© West Coast© Polarpix
Scapes / Shutterstock.com

Foreword
In the first decade of the 20th century, two German chemists – Fritz Haber andCarl Bosch – developed a way to produce synthetic nitrogen cheaply and on a large
scale. Their invention spurred the mass production of nitrogen-based fertilizers, andthus transformed farming around the globe. It also marked the beginning of ourlong-term interference with the Earth’s nitrogen balance. Every year, an estimated
US$200 billion worth of reactive nitrogen is now lost into the environment, where it
degrades our soils, pollutes our air and triggers the spread of “dead zones” and toxic
algal blooms in our waterways.
It’s no wonder that many scientists are arguing that “the Anthropocene” should
become the official name of the current geological era. In just a few decades,
humankind has caused global temperatures to rise 170 times faster than the naturalrate. We have also deliberately modified more than 75 per cent of the planet’s land
surface, and permanently altered the flow of more than 93 per cent of the world’s
rivers. We are not only causing drastic changes to the biosphere, we are also now capable of rewriting – and even creating fromscratch – the very building blocks of life.

There is some good news to report. As you can read in the pages that follow, a holistic approach to the global challenge ofnitrogen management is beginning to emerge. In China, India and the European Union, we are seeing promising new efforts to
reduce losses and improve the efficiency of nitrogen fertilizers. Ultimately, the recovery and recycling of nitrogen, as well as othervaluable nutrients and materials, can help us to farm cleanly and sustainably, a hallmark of a truly circular economy.
The issues examined in Frontiers should serve as a reminder that, whenever we interfere with nature – whether at the global scaleor the molecular level – we risk creating long-lasting impacts on our planetary home. But by acting with foresight and by working
together, we can stay ahead of these issues and craft solutions that will serve us all, for generations to come.

Joyce Msuya
Acting Executive Director
United Nations Environment Programme

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Every year a network of scientists, experts and institutions across the world work with UN Environment to identify andanalyze emerging issues that will have profound effects on our society, economy and environment. Some of these issues arelinked to new technologies that have astonishing applications and uncertain risks, while others are perennial issues, such as
the fragmentation of wild landscapes and the thawing of long-frozen soil. Another issue, nitrogen pollution, represents anunintended consequence of decades of human activity in the biosphere. While the final issue analyzed here, maladaptation toclimate change, highlights our failure to adequately and appropriately adjust to the shifting world around us.

7Acknowledgements
Synthetic Biology: Re-engineering the environment
Lead Authors
Bartlomiej Kolodziejczyk, H2SG Energy Pte. Ltd., Singapore
Natalie Kofler, Yale Institute for Biospheric Studies, Yale University,
Connecticut, United States
Contributors and Reviewers
Marianela Araya, Convention on Biological Diversity, Montreal,
CanadaJames Bull, College of Natural Sciences, University of Texas atAustin, Texas, United States
Jackson Champer, Department of Biological Statistics andComputational Biology, Cornell University, New York, UnitedStatesChen Liu, Department of Biological Statistics and Computational
Biology, Cornell University, New York, United States
Yongyuth Yuthavong, National Science and Technology
Development Agency of Thailand, Pathumthani, Thailand

Ecological Connectivity: A bridge to preserving
Biodiversity
Lead Author
Gary Tabor, Center for Large Landscape Conservation, Montana,
United States
Contributors and Reviewers
Maya Bankova-Todorova, The Mohamed bin Zayed Species
Conservation Fund, Abu Dhabi, United Arab Emirates
Camilo Andrés Correa Ayram, Alexander von Humboldt Biological
Resources Research Institute, Bogotá, Colombia
Letícia Couto Garcia, Federal University of Mato Grosso do Sul,
Campo Grande, Brazil
Valerie Kapos, UN Environment – World conservation Monitoring
Centre, Cambridge, United Kingdom
Andrew Olds, School of Science and Engineering, University of
the Sunshine Coast, Maroochydore, Australia
Ileana Stupariu, Faculty of Geography, University of Bucharest,
Romania8

Permafrost Peatlands: Losing ground in a warming
world
Lead Author
Hans Joosten, Greifswald University/Greifswald Mire Centre,
Greifswald, Germany
Contributors and Reviewers
Dianna Kopansky, UN Environment, Nairobi, Kenya
David Olefeldt, Faculty of Agricultural, Life and Environmental
Sciences, University of Alberta, Edmonton, Canada
Dmitry Streletskiy, Department of Geography, The George
Washington University, Washington DC, United States

The Nitrogen Fix: From nitrogen cycle pollution tonitrogen circular economy
Lead Authors
Mark Sutton, Centre for Ecology & Hydrology, Edinburgh, United
Kingdom
Nandula Raghuram, Guru Gobind Singh Indraprastha University,
New Delhi, India
Tapan Kumar Adhya, Kalinga Institute of Industrial Technology
Bhubaneswar, Odisha, India
Contributors and Reviewers
Jill Baron, U.S. Geological Survey, Colorado, United States
Christopher Cox, UN Environment, Nairobi, Kenya
Wim de Vries, Wageningen University and Research, Wageningen,
The Netherlands
Kevin Hicks, Stockholm Environment Institute, York,
United Kingdom
Clare Howard, Centre for Ecology & Hydrology, Edinburgh,
United Kingdom
Xiaotang Ju, College of Agricultural Resources and Environmental
Science, China Agricultural University, Beijing, China
David Kanter, College of Arts and Science, New York University,
New York, United States
Cargele Masso, International Institute of Tropical Agriculture,
Ibadan, Nigeria

Jean Pierre Ometto, National Institute for Space Research,São José dos Campos, Brazil
Ramesh Ramachandran, National Centre for Sustainable Coastal
Management, Ministry of Environment, Forest and Climate
Change, Chennai, India
Hans Van Grinsven, PBL Netherlands Environmental Assessment
Agency, The Hague, The Netherlands
Wilfried Winiwarter, International Institute of Applied Systems
Analysis, Laxenburg, Austria

Maladaptation to Climate Change: Avoiding pitfalls on
the evolvability pathway

Production team
Editor-in-chief: Pinya Sarasas, UN Environment
Technical support: Allan Lelei, UN Environment
Copy editor: Alexandra Horton, United Kingdom
Graphics, design and layout
Graphic designer: Audrey Ringler, UN Environment
Cartographer: Jane Muriithi, UN Environment
Printing
UNON/Publishing Services Section/Nairobi, ISO14001:2004Certified

Lead Author
Catherine McMullen, Stockholm Environment Institute, Bangkok,
ThailandSpecial thanks are extended toAlexandra Barthelmes and Cosima Tegetmeyer, Greifswald Mire
Centre, Germany; Marin Klinger, National Snow and Ice Data
Center, Colorado, United States; Salome Chamanje, David Cole,
Nicolien Delange, Angeline Djampou, Philip Drost, Virginia Gitari,
Jian Liu, Ariana Magini, Nada Matta, Pauline Mugo, Susan MutebiRichards, Shari Nijman, Andreas Obrecht, Samuel Opiyo, Meses
Osani, Roxanna Samii, Rajinder Sian, Nandita Surendran andJosephine Wambua, UN Environment
Production advisers
Maarten Kappelle and Edoardo Zandri, UN Environment

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Contributors and Reviewers
Thomas Downing, Global Climate Adaptation Partnership, Oxford,
United Kingdom
Anthony Patt, Institute for Environmental Decisions, ETH Zürich,
Zürich, Switzerland
Bernadette Resurrección, Stockholm Environment Institute,Bangkok, Thailand
Jessica Troni, UN Environment, Nairobi, Kenya

9

SYNTHETIC BIOLOGY: RE-ENGINEERING THE ENVIRONMENT

Photo credit: nobeastsofierce / Shutterstock.com

Synthetic Biology:

Re-engineering the environment
Opportunities and challenges
The world is facing unprecedented challenges to a healthyand sustainable future. Habitat destruction, invasive species,
and overexploitation are contributing to immense biodiversity
loss.1 Unsustainable, extractive industry practices further
burden the environment, and by extension, human welfare.
Vector-borne infectious diseases pose a major threat to
global health.2 Rapid climate change is likely to expand thegeographical range of tropical diseases and further stressalready taxed species and ecosystems.3
A number of approaches devised to meet these challenges– some proposed and others already implemented – share
a common strategy. That is, they depend upon the genetic
manipulation of living organisms to acquire new functions

10

that otherwise do not exist in nature, in order to serve humanneeds. Scientists can modify microorganisms like E. coli by
rewriting their genetic code to turn them into tiny living
factories that produce biofuel.4 Both baker’s yeast and E. coli
can be engineered to produce adipic acid – a petroleumderived chemical key to the fabrication of nylon – thus
offering an alternative to petroleum-dependent production.5,6
Baker’s yeast can also be reprogrammed to derive anantimalarial drug called artemisinin, which is normally sourced
from the sweet wormwood plant.7 These are all examples of
products made possible by the advanced genetic-engineering
technology known as synthetic biology.
The majority of commercially available synthetic biology
products have been developed to provide alternatives toexisting high-value commodities, especially those dependent

The Convention on Biological Diversity
considers that the following operational
definition is useful as a starting point for the
purpose of facilitating scientific and technical deliberations
under the Convention and its Protocols.
“Synthetic biology is a further development and new
dimension of modern biotechnology that combines
science, technology and engineering to facilitate
and accelerate the understanding, design, redesign,
manufacture and/or modification of genetic materials,
living organisms and biological systems.”20

Photo credit: BASF

on the petroleum supply chain and non-renewable resources.8
Moreover, synthetic alternatives and replacements for
substances conventionally derived from nature are also gaining
ground in research and market spaces.9-12 Modern Meadow, acompany behind the invention of a collagen-producing yeast,
aims to deliver a sustainable leather alternative with properties
and texture similar to animal-derived leather.11 Synthetic
biology has also opened up a new landscape for advanced
materials with novel functionalities and performance, such as
materials that can self-assemble or self-repair.13
The recent emergence of CRISPR (pronounced crisper and shortfor clustered regularly interspaced short palindromic repeats)
as a gene-editing tool has enabled even more precise andinexpensive methods of engineering individual organisms,
biological systems, and entire genomes.14,15 Applications ofsynthetic biology are advancing beyond the manipulation of
microbes in the laboratory to engineering the propagationof species outside controlled settings, for specific ends.
Strategies to release genetically engineered organisms into theenvironment to permanently alter entire populations of target
species have been proposed as a means to eradicate vectorsof disease, eliminate invasive species, and lend resilience tothreatened plants and animals.16

The intentional or accidental release of genetically engineeredorganisms into the environment could have significant
negative impacts on both human and environmental health.
Misuse of these technologies and a failure to accountfor unintended consequences could cause irreversible
environmental damage and pose significant geopoliticalthreats.17 The potential far-reaching impacts of synthetic
biology demand governance methods and researchguidelines that promote its ethical and responsible use.18,19

The filamentous fungus, Aspergillus niger, can naturally produce enzymes
that are commercially important in the food and animal feed industries.
The microorganism is genetically modified to enable the large-scale
enzyme production. 180x magnification.
Photo credit: BASF

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Succinic acid is a high-value chemical used in the food, pharmaceuticaland chemical industries. Basfia succiniciproducens as shown above is anatural succinic acid producing bacterium found in bovine rumen. To
achieve the industrial-scale production, it is genetically engineered for
improved productivity. 4,000x magnification.

11

SYNTHETIC BIOLOGY: RE-ENGINEERING THE ENVIRONMENT

Rewriting the code of life

DNA is in every living organism's blueprint. It guides the
production of proteins needed for an organism to function.

The development of recombinant DNA technology in the
1970s marked a major shift in how humans control genomes.21
Genetic sequencing technologies allowed for tracts of DNA tobe read and understood, providing the blueprint to engineer
genomes for new gene expressions. DNA sequences can becompletely rewritten by deleting, adding or replacing segments.
Entire portions of DNA can now be chemically synthesized andassembled, which has led to the creation of synthetic life.22
The latest gene editing tool, CRISPR-Cas9, has garneredsignificant excitement in the scientific community and generalpublic alike. First described in 2012, CRISPR is faster, cheaper,
more accurate, and more efficient than any of its gene-editing
predecessors.23,24 It has speeded up the editing process fromseveral months to just a few days.25,26
The CRISPR-Cas9 gene-editing technique was inspired by anaturally occurring defence system of certain bacteria against
viral invasion.27,28 In nature, a bacterium can deploy the Cas9
enzyme to cut invasive genetic material inserted by a virus,
effectively disabling the attack. Researchers have adapted thismechanism to cut DNA at any specific location. In CRISPR-Cas9
gene editing, scientists use a guide RNA to direct the Cas9
enzyme to a precise portion of DNA.
The Cas9 enzyme then acts as a pair of molecular scissors,
cutting or deleting the targeted segment. By exploiting thenatural DNA repair process, researchers can also insert acustomized DNA segment into the disrupted strand.29
Video: Synthetic biology explained

Video link: https://www.youtube.com/watch?v=rD5uNAMbDaQ
Photo credit: Omelchenko / Shutterstock.com

12© techNyouvids

DNA, or deoxyribonucleic
acid, is made up of four
nucleotide bases bondingin pairs.

Adeninepairs with
ThymineCytosinepairs with
GuanineJust as a combination of letters form a word with a certain
meaning, a string of As, Ts, Gs and Cs in a specific orderform a gene that produces a specific type of protein for a
specific function in the body.

When a ‘spelling mistake’, or mutation, occurs in the
DNA sequence, it affects the structure and function of
the synthesized proteins. A cell can become cancerous
as a result of ‘mistakes’ in the DNA sequence.
Scientists can determine the precise order of theletters through DNA sequencing. The complete
set of human DNA, or the human genome, has
3 billion combinations or base pairs.

ACCCAGTCGGATTCGGATCGGAGTCATCGTCGCGTG
GGATCGGATTCG

2.7 billion
base pairs

Genetic engineering
techniques have beenused for decades tomodify organisms byaltering the location ofgenetic materials, forexample in geneticallymodified organisms(GMOs), where a genefrom one species isisolated and transferred
to an unrelated species
in order to achieve thedesired characteristic in
the target organism.

651 million
base pairs
12 million
base pairs
baker’s yeast

In 2010, scientists
announced theirsuccess in creating
the world’s first
synthetic bacterial cell after adecade of learning to design,synthesize and assemble a DNA
sequence from scratch.

278 million
base pairs

Synthetic biology is the next level of genetic
engineering: the research is no longer confined
to manipulating natural genetic materials, butinvolves the programming and construction of
new biological systems using artificiallysynthetized DNA.

Using the natural baker’s yeast
genome as a blueprint, aconsortium of scientists are now
working to construct a yeast cellmade out of entirely synthetic DNA.

CRISPR-Cas9 genome editing technique
In nature, CRISPR-Cas9 is the bacteria’s defense and immunity
strategy against viral attacks, utilizing the system to precisely
identify and cut the DNA of an invading virus, thus disabling
the attack. Scientists have adapted the CRISPR-Cas9
mechanism for genome editing as it offers a more precise,relatively cheaper and faster way to modify a genome.

1
Scientists identify a section of DNA they want to modify.

Photo credit: BASF

This editing process can be likened to locating and precisely
cutting a specific word or a sentence out of a document, andif desired, replacing it with new wording. CRISPR is now being
used to repair disease-causing mutations in humans, achieve
new traits in crops, and synthesize novel microorganisms.14
More recent developments include the use of CRISPR-Cas13 toedit RNA instead of DNA.30
CRISPR gene editing is being used in research aiming to engineer
wild organisms outside human-controlled environments.
Gene drives are a synthetic biology application that depends
on CRISPR gene editing to ensure the expression of desired
gene edits in future generations of a wild species.31 The process
involves an organism being engineered in a laboratory to
encode a CRISPR-based gene drive and a desired gene edit. This
organism is then released to mate with the normal population in
the wild, forcing the inheritance of the desired gene edit alongwith the gene drive system in its offspring. The gene drive is aself-perpetuating process that repeats whenever the offspringmates with the wild population. And over time, the entire
population of that species will all carry both the desired gene
edit and the gene drive system. CRISPR-based gene drives canalso ensure the inheritance of traits that disrupt reproduction,such as sterility, which could spread in a population andpotentially lead to extinction. The application of CRISPR-based
gene drives is most suited to sexually–reproducing species withshort generation times, like most insects and some rodents.32

2
Scientists then create a genetic sequence, called a guide RNA,
that matches the targeted DNA section, and bind the guide RNA
to the Cas9 enzyme, which acts as a pair of molecular scissors.

Guide RNA

Cas9

3
Guide RNA locates the targeted section and tells Cas9 where to cut.

4
A new piece of DNA can be inserted at the site to replace the cut section.

UN ENVIRONMENT FRONTIERS 2018/19 REPORTThe spherical spores produced by fungus Emericella nidulans are coated in alayer of the protein hydrophobin which repels water. The gene responsible
for hydrophobin production has been introduced into E. coli bacteria to
manufacture the protein with commercial applications. 400x magnification

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SYNTHETIC BIOLOGY: RE-ENGINEERING THE ENVIRONMENT

Synthetic Biology

Sustainability applications

Market and investment

Many industries have made use of synthetic biology.
Microorganisms, from bacteria to yeasts, aregenetically engineered to become tiny factories
producing more sustainable ingredients for
medicines, vaccines, biofuels, green chemicals andnew materials.

US$13.9 billion
Projected global market
value of synthetic biology
applications by 2022

US$1.9 billion

Pharmaceutical products2018 Global
investment insynthetic biology
startups

E. coli is altered
to manufacture a
vaccine againstchlamydia, which is
becoming moreresistant toconventional
antibiotics

Alternatives to chemicals derived
from unsustainable sources
The blood of horseshoe crabs is amajor biomedical commodity used inpharmaceutical testing for bacterial
contamination. A synbio substitutecould reduce or replace
the need for harvesting
the nearly extinct
species from theoceans.

Green and bio-based chemicals
A variety of chemicals in everyday
products are derived from petroleum.
Synthetic biology enables the
production of substances that canreplace petroleum-based chemicals.

Lactic acid,succinic acid andpropanediol are amongchemicals made by
genetically engineered
microbes that arecommercially available
in the global
marketCRISPR-Cas9 genome editing technique
The discovery of CRISPR-Cas9 has changed
the entire outlook of synthetic biology research.
It enables scientists to cut out a particular DNA
segment of a desired sequence or replace it with a new
DNA strand. Many fields of medical research require suchediting precision to revolutionize treatments.
However, the technique is also subject to scrutiny for its
safety as it involves a potential off-target effect, whereby it
inadvertently cuts out DNA that has a similar sequence to thetargeted strand, potentially triggering cancer in edited cells.

14

Do-It-Yourself Biology
or DIY Bio

Risks and policy
considerations

The movement of so-called ‘citizen
scientists’ interested in performing
synthetic biology experiments has
gained significant traction globally.
Biology enthusiasts – many without
scientific background – meet ingarage labs to conduct experiments
using specialised DIY kits and simple
protocols available online.

There are concerns that synthetic
biology could be used to
re-engineer existing pathogenic
viruses, making them moredangerous or produce biochemicals
with only modest resources andorganizational footprint.

Some of the group have specialised
equipment and hire professional
staff to help citizen scientists,biohackers and biology enthusiasts
in developing their projects.

Synthetic biology presents newchallenges that need to beaddressed through theconsolidated action of
governmental and international
bodies. Development of effective
methods to better manage
emerging risks is essential inensuring technological safety.

Applications for conservation and public health
CRISPR-based gene drives may be key to addressing someglobal challenges, such as vector-borne diseases or invasive
species, but they require multifaceted societal debate
because of their power to modify, suppress or replace theentire population of the target species, bypassing thefundamental principles of evolution

Gene drives
have been madepossible by thedevelopment of
CRISPR-Cas9
technology

Gene drives with
suppression intent canforce the inheritance of
detrimental genetic alterations,such as sterility, potentially reducing
the target population to zero. The
suppression drive is intended tocontrol the populations ofmalaria-carrying mosquitoes
in the environment.

The
release of only a
few gene-drivebearing organisms into
the environment cantransform an entire
species population andpotentially the wholeecosystem

American chestnut trees are near extinction due tochestnut blight, a fungal disease native to Asia.
Pending regulatory approval, the American chestnut
can be engineered to be blight-resistant and spread in
the wild.

Genetic
cross-contamination
between species andunintended
ecological damage aresome of the legitimate
concerns that have
not yet been
resolved

CRISPR-based gene drives: Manipulating the wild populations of plants and animals

Ordinarymosquito

Mosquito withunique trait

50% chanceof inheriting
unique trait

Gene drive inheritanceA synthetic gene drive circumvents the rules of normal
genetic inheritance. This self-perpetuating mechanism isdesigned to ensure preferential inheritance of a modified
genetic trait in future generations. Over time the entire
population inherits the preferred engineered trait.

Ordinarymosquito

Mosquito withgene drive

100% forced
inheritanceof trait

During fertilization,
the offspring
inherits one set of
DNA from theordinary parent andone containing the
CRISPR-equipped
gene drive from thegeneticallyengineered parent.
CRISPR-Cas9 looks
for the target site in
the ordinary DNA
and cuts it.

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Normal inheritanceIn sexual reproduction, each parent passes half its DNA to its
offspring. A parent’s unique genetic trait has a 50-50 chanceof being inherited by the next generation. Over many
generations the unique genetic character still remains in the
population but at low frequency. The normal inheritance also
applies to the case of an offspring produced by a normalparent and a classic GMO parent.

When the cut DNA
attempts to repair
the damage, it
copies theengineered strand
containing the gene
drive.
The offspring ends
up having two
copies of thegeneticallyengineered DNA
with gene-drive
capability to passon to future
generations.

15

SYNTHETIC BIOLOGY: RE-ENGINEERING THE ENVIRONMENT

Applications redefined: From laboratory to
ecosystem

Video: Genetically modified mosquitoes

Synthetic biology could indirectly benefit conservation
efforts by allowing the development of artificial alternatives
to commercial products normally sourced from the wild.
For example, the blood of the horseshoe crab is a major
biomedical commodity used to test pharmaceuticals forbacterial contamination. Unsustainable harvesting is pushing
the species towards global extinction.33 A synthetic substitutehas been developed that could reduce or replace the needto harvest the endangered crabs.34,35 Likewise, engineered
microbes and microalgae capable of producing alternatives
to omega-3 oils could lessen pressure on declining wild fishstocks.36
Conservation measures that propose a more direct
application of the technology on target species have recently
emerged. Releasing genetically engineered organisms into
the environment could restore the health or enhance theresilience of damaged populations. For example, using anapproach that predates CRISPR, scientists have synthesized
the oxylate oxidase gene normally expressed by wheat, andforced its expression in the American chestnut tree. This
gene can neutralize the toxin secreted by the blight that has
driven the tree functionally extinct.37,38 Pending regulatory
approval, blight-resistant chestnuts could be planted to reestablish this once-dominant species in eastern U.S. forests.
Unlike genetically modified crops, where safety concerns
largely centre around containment, the engineered Americanchestnut is deliberately designed to spread and flourish in thewider environment.
As climate change is predicted to increase rates of species
extinction worldwide, CRISPR’s availability is likely to hasten
applications for ecosystem restoration.39 Scientists haveproposed using CRISPR for threatened species, such ascorals that are under immense stress from increased ocean
temperatures, acidification and pollution. Proof-of-concept
CRISPR research is underway to rewrite coral genomes
to express mutations that endow resilience.40,41 However,frameworks for field implementation of this research have yet
to be developed.

16

Video Link: https://www.youtube.com/watch?v=zlSTGkDyEfM
Photo credit: Ajintai / Shutterstock.com© biointeractive

CRISPR-based strategies could also remove invasive species
from threatened ecosystems. On many Pacific islands,
for example, invasive rodents are decimating native bird
populations.42 Through international collaboration, theGenetic Biocontrol of Invasive Rodents programme isdeveloping CRISPR-based gene drives that would spreadsterility.43,44 In New Zealand, CRISPR-based gene drives arebeing considered to help achieve the elimination of allinvasive predators by 2050.45 In Hawaii, gene drives havebeen proposed to reduce avian malaria spread by housemosquitoes that has caused serious declines in rare bird
populations.46,47 However, recent research indicates thatgene drives may face resistance and limited efficacy in wild
mosquito populations.48,49
It has even been suggested that extinct species could beresurrected for their ecological benefits, such as reviving awoolly-mammoth-like animal by gene editing the DNA of its
closest living relative, the Asian elephant.50,51 Proposals for deextinction of species are not only highly debatable, but also
re-emphasize the importance of addressing the root causeof extinctions. Such possible genetic interventions, even if
unrealized, encourage a valid debate on how biotechnology
can support, coexist with, or undermine the goals ofconservation.52

Video: Why horseshoe crab blood is so expensive
De-extinction

Video: What is a gene drive?

Normal inheritanceVideo Link: https://www.youtube.com/watch?v=75iP50LEHrU

Gene drive inheritance© STAT

Video link: https://www.youtube.com/watch?v=LgQZWSlLBnA
Photo credit: Lysogor Roman/ Shutterstock.com© Business Insider

To reduce the global disease burden, various synthetic biology
strategies aim directly at suppressing populations of disease
vectors. A company called Oxitec has genetically engineeredmosquitoes to express a synthetic lethal gene and has
released them in South America, South-East Asia, and several
Caribbean nations to suppress the vector for Dengue fever,
Zika virus, yellow fever, and chinkengunya.53,54 These so-called‘self-limiting’ mosquitoes pass a lethal gene to their offspring,
preventing them from surviving to adulthood. This method of
suppression is, however, reversible without continual releases
to sustain the engineered mosquito population in the wild.
To circumvent this issue, Target Malaria, an international
consortium funded by the Bill and Melinda Gates Foundation,
is developing CRISPR-based gene drives to permanently
control the malaria vector in sub-Saharan Africa.55 CRISPRbased gene drives are highly invasive as, in theory, a onetime release of a few gene-drive-bearing organisms could
completely suppress an entire wild population. Anotherstrategy is to use gene drives that do not suppress the
population, but instead limit the ability of mosquitoes totransmit pathogens.56 CRISPR-based gene drives have also
been devised to permanently immunize white-footed miceagainst Lyme disease on islands in Massachusetts, USA.57

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Attempts to revive species that have recently become
extinct or are close to extinction have been made todate using back-breeding and cloning techniques.58-60
These approaches depend on the availability of tissues
from extinct animals to clone, and extant species forcrossbreeding or to serve as a surrogate.61,62 None of thede-extinction efforts have succeeded so far. Bringing backspecies that have long disappeared from the planet andleft very little trace of their DNA is only remotely plausible.
It would require the reconstruction of the entire genome
and the existence of a closely related species for viablesurrogacy. Even if the technological difficulties can one
day be overcome, significant challenges remain in relation
to how the de-extinct species would function in today’senvironment. Fundamental ecological concerns include
the uncertainty of species competition and interaction;
the susceptibility of de-extinct species to diseases andparasites; the possibilities of serving as a disease
vector or becoming invasive species
themselves; and the probability of
establishing and sustaining a healthy
population from individuals withlow genetic diversity.61

17

SYNTHETIC BIOLOGY: RE-ENGINEERING THE ENVIRONMENT

Innovating with wisdom
The release of genetically engineered organisms accidentallyor intentionally into the environment has raised valid
concerns about biosafety and unpredictable consequences.
For organisms engineered in closed research or industrial
facilities, containment procedures and enforced regulations
on waste disposal help to avoid an escape, although this isnever fail-proof.63 In the case of intentional release, concerns
over potential genetic cross-contamination between species,
ecological interactions and impacts on ecosystems and theirservices remain largely unresolved.64 Altering a disease carrier
genetically could potentially cause a pathogen to evolve andbecome more virulent, or to be carried by a new vector.65
To date, CRISPR-based gene drives have been tested only
on small populations in controlled settings, with one recent
experiment successfully collapsing the entire malariacarrying mosquito population in the laboratory.66 As a firststep towards wider trials, Target Malaria has recently gained
permission to release 10,000 modified mosquitoes in Burkina
Faso. These specimens will be genetically engineered to besterile, but with no gene drives, to test how well they competewith wild males.67 However, such field trials to evaluate theefficacy of the gene-drive system could pose inherent risks.68,69
Under the precautionary principle, stringent risk assessment
and the inclusion of diverse stakeholder perspectives should
be applied in the development and handling of innovativesynthetic biology applications and products.19,70,71 The
precautionary principle states that when human activities
may lead to unacceptable harm that is scientifically plausible
but uncertain, action should be taken to avoid or diminish
that harm.72 A concept of substantial equivalence – that agenetically modified organism is as safe as its traditionalcounterpart – is often mentioned in conjunction with the
precautionary principle.73 Some countries have extensive
policy and regulations in place concerning genetic
engineering and research, while for others, non-functional
regulatory systems, policy gaps and risk-assessment capacity
are major challenges.74-77
Attempts have been made to identify, evaluate and address
the ethical and biosafety concerns of synthetic biology.
The U.S. National Academies of Science, Engineering,18

and Medicine published a report on gene drives in 2016highlighting the need for stringent environmental risk
assessments and deliberation that charters human values andnecessitates rigorous public engagement.19
In December 2017, the ad-hoc technical expert group on
synthetic biology, established by the Parties to the Convention
on Biological Diversity, concluded that organisms – developedor being developed through current methods of synthetic
biology, including those containing gene drives – fall under
the description of living modified organisms (LMOs), which
are regulated under the legally-binding Cartagena Protocol.78
With 171 Party nations, the Protocol applies the precautionary
approach and requires that each Party take all necessary
measures to ensure the safe handling, transport and use of theresulting LMOs.79
SYNBIOSAFE, an EU-funded research project, was established
to identify key issues in safety, security, risk management
ethics and, importantly, the science–society interface, whichemphasizes public education and dialogue among scientists,businesses, government, and ethicists.80,81 Some gene-drive
developers have also proposed ethical research guidelinesthat emphasize the need for meaningful public engagement.82
Video: Why is this African village letting
mosquitoes in?

Video Link: https://www.youtube.com/watch?v=ooYShrGtkUQ
Photo credit: Dmitry Trashchenko / Shutterstock.com© BBC News

Video: Could genetically engineered mice
reduce Lyme disease?

Citizen scientists, biohackers and garage labs
Synthetic biology and genome editing have attracted
interest not only from companies, but also regular
citizens. Do-It-Yourself Biology, also known as “DIY Bio”,
the movement of “citizen scientists” interested in synthetic
biology experiments has become an international
phenomenon over the last decade. Often with little priorknowledge of the field, enthusiasts meet in makeshiftlabs to take crash courses in biotechnology and conducthands-on experiments.90,91 Simple protocols found online
and specialized kits costing US$150–1,600 have driven the
movement’s rapid expansion.

Nevertheless, the intentional release of modified organisms
and their potential to permanently transform wild species
and cross international borders will likely test the limits ofcurrent policy, leading some environmental groups to call fora moratorium on all gene-drive research.83 Other regulatory
concerns focus on the potential use of synthetic biology for
military offensive purposes.84,85
Current ethical frameworks may not be able to keep
pace with the rapid progress of synthetic biology and its
inherent complexity, especially concerning wild species.86
Decisions to release engineered organisms into the wild
will be shaped by the pervading environmental ethic, or
how a majority of citizens relate to non-human nature.87
Altering the genetic code of wildlife is seen by some asa gross overstep by humans, echoing concerns about
genetically modified crops. Others may feel that there is a
moral responsibility to use a technology that could save lives
or restore damaged ecosystems.87 These contrasting value
systems require responsible decision-making for resolution.89
Synthetic biology applications also raise questions of who
has ownership of an LMO and its genome, what protection
is available for vulnerable communities, and how to ensure
those most impacted have a voice. It is crucial that balanced
and inclusive deliberative forums steer the field of synthetic
biology and ensure that its environmental applications areused to the benefit of all on our shared planet.

DIY Bio labs can be found in most major cities and by 2017
there were about 168 groups worldwide.92,93 Regulating
the use of easily accessible and low-cost technologies
like CRISPR and gene editing kits will likely be a challenge
for authorities. There is also growing concern that thetechnology could be misused by terrorists to destroy
agricultural crops or turn harmless microbes into biologicalweapons.94
60

50

40

30

20

10

0
2006

2008

2010

2012

2014

2016

United States of America

Australia and New Zealand

CanadaAsia

EuropeLatin America

Source: The Brookings Institute93

UN ENVIRONMENT FRONTIERS 2018/19 REPORT© PBS NewsHour

Number of DIY Bio Groups

Video Link: https://www.youtube.com/watch?v=FOCNixYPsf4
Photo credit: Szasz-Fabian Jozsef / Shutterstock.com

19

SYNTHETIC BIOLOGY: RE-ENGINEERING THE ENVIRONMENT

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106,107

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ECOLOGICAL CONNECTIVITY: A BRIDGE TO PRESERVING BIODIVERSITY

Photo credit: ALEX_ UGALEK / Shutterstock

Ecological Connectivity:

A bridge to preserving biodiversity
Reconnecting fragmented ecosystems
Nature was once vast and boundless, but in an industrialized,
21st century world, this is no longer the case. Across the globe,
landscapes and seascapes are becoming more fragmented.
Wildlife has less freedom to roam and free-flowing rivers are
increasingly rare. Along tropical coastlines, previously seamless
gradients of mangroves, seagrass meadows and coral reefs
are now more fractured, undermining essential productivity
and ecosystem resilience to natural and anthropogenic
disturbances.1 A consequence of the segmentation of naturallandscapes is that mammals and other species are moving
less than half the distance they once did.2 This limited ability
to migrate, disperse, mate, feed and thrive means that wild
animals are cornered into situations where the threat ofextinction looms larger.

24

Fragmentation is typically a symptom of landscapetransformation and destruction. The division of habitat intofragments has three specific effects: a reduction of overall
habitat area and quality, increased isolation of small habitat
patches, and increased disturbance associated with artificial
boundaries of habitat fragments, or ‘edge effects’.3-6 Isolated
and smaller patches of habitat mean fewer species and smaller
populations in each patch, with restricted interactions among
habitat patches. Increased fragment edges expose populations
within the patch to external disturbances along the boundaries.
Eventually, when a patch becomes too small and isolated, viable
populations and species richness can no longer be sustained.5
Fragmentation ultimately leads to a downward spiral ofcascading ecological dysfunctions, from the unravelling of foodwebs, to the loss of critical ecological processes such as mineraland nutrient flows, to direct extinction of species.3,5,7-9

Despite the obvious advantages, the world’s nations currently
lack a consistent approach to implementing connectivity
conservation. What are the best measures to assess successfor connectivity conservation? How do governments andconservationists create corridors, design ecological networks,
or determine the effectiveness of connectivity conservation
efforts? The conservation of intact landscapes and seascapes
through the designation of more or large-scale protectedareas is feasible, but requires making difficult political, socialand economic choices.14,15 Connectivity as a conservation
target requires shared goal setting among stakeholders toensure multidimensional consideration and implementable
coordinated action. Public and private sectors must work
together for effective outcomes because stopping biodiversity
loss and reducing the impact on ecosystems is a shared
responsibility of both sectors, from the community level toa global scale. In many instances, connectivity efforts can
incorporate local socioeconomic concerns within a larger
conservation framework.
Species richness andinteractions, andabundance

Genetic variability
and gene flow

Movement anddispersal

Risk of zoonotic
disease emergence,outbreaks and human
exposure to diseases

Habitat fragmentation
About 40% of terrestrial ecosystems have been
converted into agricultural landscapes.16 Land andriver transformation for human use leads to habitat
fragmentation. Smaller and more isolated fragments ofhabitat surrounded by human activities are less likely tomaintain the function and survival of animal and plant
inhabitants. Habitat fragmentation negatively affects
abundance, distribution, movement, species richness andinteractions, reproduction and genetic diversity.5 It impairs
the ability of species to adapt to new climatic conditions.17

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Maintaining or restoring connectivity between fragmented
habitats or landscape patches has been identified as the
key to counteracting many of the negative impacts offragmentation.10 Connectivity can be defined as the degree towhich landscapes and seascapes allow species to move freely
and ecological processes to function unimpeded. Scientificevidence built on island biogeography research and species
meta-populations studies overwhelmingly demonstrates
that connected habitats are more effective in preserving
species and ecological functions.11,12 Connected ecologicalcommunities and habitat patches sustain vital ecologicalprocesses such as pollination, productivity, decomposition,and biochemical and nutrient cycling. Ecological connectivity
can also help species adapt to future environmental
conditions and buffer changes by bolstering ecologicalresilience to disruptive threats such as climate change.13

25

ECOLOGICAL CONNECTIVITY: A BRIDGE TO PRESERVING BIODIVERSITY

The forces of fragmentation
Societies are transforming the Earth’s biosphere andreshaping its ecology in unprecedented ways. The latest
research indicates that more than 75 per cent of the planet’s
land surface has been modified by humanity.18-21 Human
population pressures, growing urbanization, agricultural
expansion, pollution, and infrastructure development all workin synergy as fragmentation forces. Some land-use projections
estimate that by 2050, roughly one billion hectares of tropicalland could be cleared specifically for agricultural needs.22 The
marine environment is even less immune to these trends: newresearch shows that of the world’s oceans, only around 13
per cent is still classified as marine wilderness, much less thanmany conservationists had expected.23
Linear infrastructure is often the tip of the spear of modern
development. Roads, rails, pipelines, fences, and canals arebeing built at record rates, especially in remote, previously
undeveloped regions of the tropics. Ninety per cent of all
new road construction is expected to occur in developing
nations.24 In India, where nearly 60 per cent of the world’s tiger

population is found, critical tiger corridors are threatenedby 4,300 kilometres of newly planned national and stateroads.25 Globally, over 25 million kilometres of new roads are
anticipated by 2050 – a 60 per cent increase in the total lengthof existing roads in 2010.26
Free-flowing rivers, the ecological lifeblood of landscapesand estuaries, are challenged by the fragmentation resulting
from the size and scale of the ongoing construction of dams.
Large dams divide 59 per cent of global rivers into sections,disrupting the natural flow of 93 per cent of the global rivervolume, with nearly 28 per cent considered to be underheavy or severe flow regulation.27 In the Amazon basin alone,
there are currently over 400 dam projects being developed,
constructed, or planned.28 Together, dam construction, roadbuilding and deforestation work to undermine the ecologicalintegrity of continental river basins, which also has realconsequences for other human economic and recreational
activities. For example, freshwater connectivity contributes
approximately US$200 million per year to the Amazon basin
fishing economy that provides employment for roughly
200,000 anglers.29

Landscape fragmentation by roads

An analysis of a dataset of 36 million km of roads across the world shows that roads have fragmented the earth landscape into more than 600,000 patches.
More than half of these patches are within 1 km range of any road (in red). Moving towards the blue shade are land patches further away from all roads
and less influenced by road effects.
Source: Ibisch et al. (2016)30

26

Xingu River in northern Brazil in 2000 and 2017
2000

2017

The construction of the Belo Monte hydroelectric dam project in 2011 has completely reshaped the Xingu River. More than 80% of the river flow has been
diverted, causing large areas to dry up and directly affecting indigenous communities and wildlife living in the area.
Photo credit: Joshua Stevens / NASA Earth Observatory

Video: Seed dispersal and forest fragmentation

Video link: https://www.youtube.com/watch?v=0m6AjWZ2p8I
Photo credit: Jess Kraft / Shutterstock© HHMI BioInteractive

UN ENVIRONMENT FRONTIERS 2018/19 REPORTRivers, landscapes and coastlines are inextricably linked.
Connectivity is also a recognition that nature operates as anintegrated sum of its parts. Connectivity between aquaticand terrestrial systems is vital to ecological integrity andtoo often, these elements are managed as separate units.
In temperate ecosystems, for example, research has shownthat the footprint of gravel-bed river floodplains extends
well beyond riparian zones. This influence on sub-surface
terrestrial ecology projects beyond visible river channels
and their deltas, reaching further into the marine realm.
Free-flowing river systems work to connect aquatic, avian,and terrestrial communities – from microbes to grizzly
bears – influencing the biogeochemistry of landscapes andseascapes along the way.31

27

ECOLOGICAL CONNECTIVITY: A BRIDGE TO PRESERVING BIODIVERSITY

Landscape fragmentation and connectivity
Landscape fragmentation is the subdivision of large, continuous habitats into
smaller, more isolated pieces or patches.

Landscape connectivity is a measure of the extent to which a particular landscapeallows the free movement of animals and other ecological flows.

As the climate warms, maintaining connectivity between areasof different temperatures could allow organisms to move alongtemperature gradients, permitting species to adapt
Well-connected spaces allow species to migrate to new
habitats, especially when they need to adapt to climate changeRoadschange thebehaviour ofsome species. Studies
found animals likehedgehogs, rattlesnake,turtles, red squirrels
and snails avoided
crossing roads.

Transport
infrastructuresuch as roads
and railways
disrupts the
movementof wildlife

Habitatfragmentation has
been found to cause areduction in thenumber of top
predators

Connectivity enhances
plant–animal
interactions such as pollination andseed dispersal. Plants in moreconnected areas produce more fruit.

28

Globally, theconstruction ofover 3,700 largehydropower dams
is planned

A global study
found that 177
mammalian species
had lost more than 30%of their geographic ranges
and 40% of these species
exhibited huge declines
in populations

Riverfragmentation ismostly caused by dams andreservoirs, which disconnect
upstream and downstream
ecosystems, affecting pathways
for species dispersal andmigration as well astransport of organic andinorganic matters

Factors such as
road width, trafficload, and curvatureof the road can also
influence how many
species are killed

Land–seaconnectivity
encompasses biologicalmigration, hydrologicalcycling, nutrient transport,
and other climatic
processes, which arevital to both coastal andglobal ecosystems

Modernforestry practices
degrade theconnectivity oflandscapes
By 2030, nearly
40% of the world’s
rivers will beseverely
fragmented

A
major study of the
Amazon concluded that thebest way to protect it fromhuman activity and ensure
resilience against climatechange would be to create
very large, extensive
and connectednature reserves

Ecological corridors are strips of vegetation that connect
patches of habitat to one another, facilitating movement ofplants and animals
59% of theworld’s river
basins containlarge dams and thisfigure will reach
75% by 2030

Stepping stones are relatively small patches of native vegetation
scattered throughout a landscape, promoting species movement
and long-distance dispersal
Stepping stones allow species to move between isolated
habitats and colonize new habitats

Wellconnected marine
habitats are
more resilient toclimate change

Connectivity isvital for organisms intropical and sub-tropicalshallow coastal watersthat depend on migration
between coral reefs,
mangroves, estuaries, andriver ecosystems

In Moreton Bay,
Australia, a study
found that coral reef
patches with higher
connectivity with
mangroves had a greater
abundance of species thanthose that wereisolated frommangroves

UN ENVIRONMENT FRONTIERS 2018/19 REPORTThe creationof corridors
between nature
reserves facilitates
habitat connectivity,
which increases species
richness in thereserves

In
Brazil, a study ofhighly sensitive bird
species found that moreconnected forests
had more bird
species thanless connected
forests

29

ECOLOGICAL CONNECTIVITY: A BRIDGE TO PRESERVING BIODIVERSITY

Promoting connectivity solutions
Connectivity conservation is the antidote to fragmentationand in a time when the threats to nature are at scales
that stretch both human and financial-response capacity,
progressive initiatives are being implemented by somecountries. In Brazil, connectivity conservation underlies
the country’s ambitious efforts to restore viable habitat
connections within the heavily fragmented Atlantic rainforest,
the Mata Atlantica. Some endangered species have been
the focus of restoration projects aiming to connect isolated
populations, for example, the golden lion tamarin. Targeted
restoration has been shown to reduce species extinction
rates in once-fragmented forest blocks.32 Connectivity is
now the stated objective of various Brazilian biodiversity
policies. The Brazilian Forest Act and Brazil’s Native Vegetation
Protection Law specifically highlight connectivity as a criticallandscape restoration and habitat conservation strategy. 33,34
The government of El Salvador has recently proposed thatthe period 2021–2030 be declared the “United Nations Decadeof Ecosystem Restoration” with the aim to restore and enhancelandscape connectivity and ecological functions.
In Africa, the Government of Tanzania recently passed a new
Wildlife Conservation Act that emphasizes the need for greater
wildlife corridor conservation among its protected areas. In
Kenya, where most wildlife is found outside of protected areasand county-level planning has just begun, the Kenya Wildlife
Service has systematically catalogued the nation’s key wildlife
corridors and dispersal areas, and has crafted a national
wildlife corridor policy.35
Within the global marine realm, connectivity functions
in a three-dimensional way as the water column adds anadditional variable to movement ecology. The sea itself is aconnecting medium. Thus, marine connectivity is manifested
in multiple ways across marine-coastal connections, surfaceseafloor interactions, and as part of ocean current dynamics.36

Seascape connectivity
Seascape connectivity is the degree to which the seascape facilitates or impedes movement

Coastal habitats exist as components of functionallyconnected mosaics. Fragmentation or loss of a habitat
is likely to impair the integrity of adjacent counterparts

Mobile organisms move between ecosystems toforage, spawn and migrate, while sessile species
rely on tidal regimes and currents to deliver foodand nutrients and disperse larvae

Patch size impacts ecological processes such ascolonization, reproduction, mortality, predator-preyinteractions, and the transport of materials, energy,
and marine organisms across seascapes.

30

Furthermore, the complex life histories of many marine
species have evolved with the movement dynamics of thisfluid world. Seagrasses and mangrove swamps are well-known
nursery habitats for the young of many marine species, whichthen often need to travel to coral reefs, seamounts, or otherwaters to mature. Seascape connectivity is emphasized asa key guiding principle in marine conservation and spatialplanning, as well as restoration efforts; however, in practice
it is rarely incorporated into the design of marine reserve
networks.36-39 This is largely due to the scarcity of quantitative
data on multiple aspects of connectivity in the design phase,for example, the dispersal and movement patterns of key
species at different life stages, ecological connectivity within
and outside reserves – as well as between habitat types, andgenetic connectivity among populations.10,38-40 Nevertheless,studies of interactions between connectivity and theperformance of marine reserves in the Caribbean, Florida Keys,
Solomon Islands, Moreton Bay and the Great Barrier Reef inAustralia demonstrate the ecological importance of greater
connectivity. Positive effects on fish abundance, species
richness and composition, recruitment and various ecologicalprocesses were observed in these protected areas.10,41-44

Video: What’s marine connectivity?

Video link: https://www.youtube.com/watch?v=MowPR5GYqKM
Photo credit: Damsea / Shutterstock© Ifremer

Video: Behind the scenes of the red crab
migration—Christmas Island 2012

Efforts have been made by the international community topromote connectivity solutions. In 2016, the International
Union for Conservation of Nature (IUCN) established theConnectivity Conservation Specialist Group (CCSG) tocatalyze and energize the growing practice of connectivity
conservation. Comprising around 900 members from 80
nations, the CCSG is focused on building capacity for thepractice of consistent connectivity conservation worldwide
by developing networks and providing guidance through a
combination of scientific, engineering and policy expertise.
Video link: https://www.youtube.com/watch?v=n9yl51LQ0sI
Photo credit: David Stanley© Parks Australia

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

It is almost impossible for Marine Protected Areas, thecornerstone of ocean conservation, to function as ecologicalisolates in this highly connected environment. As such, thesea is conducive in creating ecological networks that connect
critical habitats across space and time.

31

ECOLOGICAL CONNECTIVITY: A BRIDGE TO PRESERVING BIODIVERSITY

Setting targets for future connectivity
The Aichi Biodiversity Targets adopted as part of theimplementation of the Strategic Plan for Biodiversity
2011–2020 by the Convention on Biological Diversity (CBD)
encompass the issues of landscape and seascape connectivity.
The Aichi Biodiversity Target 11 states that at least 17 percent of terrestrial and inland water areas and 10 per cent ofcoastal and marine areas are to be protected worldwide in awell-connected system of protected areas. Yet many scientists
believe that current biodiversity conservation deserves amore ambitious goal.45,46 The conservation science community
argues that, on average, 50 per cent of all lands and seasneed to be managed in order to sustain the ecologicalprocesses that maintain nature and critical planetary healththresholds, including ecosystem services that support
human livelihoods.4,14,15 For many areas of global ecologicalsignificance, a bolder target is scientifically warranted andpolitically supported. For instance, the Amazon basin requires
greater protection to sustain this vast watershed’s regionaland global hydrological and climate functions. If the Amazon
loses more than 20 per cent of its forests, landscape models
predict a threshold flip in conditions that would support
tropical savannah rather than forest, resulting in impacts
on global climate patterns.47 In implementing the Aichi
Biodiversity Targets, the Brazilian government established its
own goal to protect 30 per cent of the Amazon while ensuringthat other biomes within its territory would individually meetthe 17 per cent target.48 The next ten-year CBD strategicplan covering 2021–2030 will be negotiated in October
2020 in China. There is enthusiasm among the conservation
community that the goals of Aichi Biodiversity Target 11 could
be framed more ambitiously and in line with the aspiration of“50% for Nature” by the year 2050.
While much effort has focused on meeting the protection
percentages for lands, freshwater and seas, it is also
recognized that more could be done on the modifying
element of a well-connected system of protected areas, andother effective area-based conservation measures. The science
unequivocally demonstrates that connected protected areas
are more effective protected areas.49,50 Connecting fragmented
landscapes and seascapes through ecological networks caneffectively enhance the functionality of nature and boost
more ambitious approaches to conservation.

32

Wildlife corridors are a widely accepted
connectivity strategy for protecting species
migrations. Corridors are often designed for and focusedon a particular species, such as pronghorn antelope inNorth America, tigers in Asia, and spotted jaguar in SouthAmerica. Corridors come in an array of shapes and sizes
depending on the species of concern and the constraintsof the landscape, ranging from discrete linear trails toseries of “stepping stone” habitat patches that facilitate
migration of birds or sea turtles.
Linkage zones are larger landscape or seascape areas thatserve a wide array of species and ecological processes inorder to maintain connectivity. These zones comprise large
swathes of land or sea that facilitate dispersal between
protected areas, which is critical in places like East Africa
where an overwhelming majority of wildlife is foundoutside of protected areas. Linkage zones also facilitate
the movement of animals, biomass, and energy between
habitat patches, or among different ecosystems withinprotected areas.
Permeability areas are the largest-scale concept used byconservationists to protect connectivity values in humandominated regions outside of protected areas. These areas
support the seasonal needs or spatial extent of species
movement and/or ecological processes, such as vernalpools or specific freshwater hydrologic flows.
Climate corridors are proposed by scientists as a means toconserve species movements along temperature gradients;
these same corridors often serve as ‘climate refugia’.51 Someconnectivity conservation efforts explicitly include climate
resilience in their objectives, such as the Great Eastern
Ranges Initiative in Australia.52

Presently 14.7 per cent of land around the world is coveredby protected areas and less than half of this coverage
is connected.50 As this statistic suggests, there is muchopportunity for improving connectivity between protectedareas globally. If the world seeks large-scale conservation
action rapidly, connecting protected areas through ecologicalnetworks offers hope.

Stepping stones and crossing

Protected areas alone cannot save biodiversity or conserve
the interconnected ecological functions that sustain
life on this planet. Connectivity is the embodiment of
ecology, which is the science of interdependence. This isimperative as interconnected lands, freshwater and seas
are the lifeblood of intact nature. Thus, connected networks
represent the best opportunity to maintain and restore
ecological and evolutionary processes, avoid extinctions,and protect terrestrial, freshwater, and marine ecosystems
vital to humanity and all life. Connectivity could ensure that
ecosystems around the world will be more resilient andadaptable to global change, and will have the ability to sustain
the ecological integrity that meets the needs of present andfuture generations. Until the forces of fragmentation are
overcome, connectivity conservation by design creates asafety network for biodiversity conservation – and ultimately,
humanity.

UN ENVIRONMENT FRONTIERS 2018/19 REPORTThe application of connectivity conservation is still relatively
nascent within wider conservation practice, and there ismuch to learn to perfect best practices.53.54 As an emergent
practice, ecological connectivity conservation faces its
greatest implementation challenges outside of protectedareas. Limiting impacts from fragmenting forces such as
linear infrastructure development is obviously a critical need.
Educating policymakers, government agencies, and local
community stakeholders about the importance of ecologicalconnectivity is equally crucial. While some nations could
introduce regulatory measures to conserve connectivity, thevast majority of ecological connectivity efforts will rely on
incentive-based participatory conservation approaches.55
The adaptation of existing environmental policies could
facilitate the wider adoption of connectivity conservation by
including connectivity targets within both environmental
impact assessments, and various conservation finance and tax
incentive programmes.

33

ECOLOGICAL CONNECTIVITY: A BRIDGE TO PRESERVING BIODIVERSITY

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10, 40-43, 73

37

PERMAFROST PEATLANDS: LOSING GROUND IN A WARMING WORLDPermafrost Peatlands:

Permafrost peatlands with numerous lake depressions, Cape Bolvansky, Russia
Photo credit: Hans Joosten

Losing ground in a warming world
Accelerating change in the Arctic

38

Peatlands located in the tropics receive much attention as
global hotspots for their critical role in carbon storage andclimate change mitigation. They store nearly 120 gigatons ofpeat carbon, but this is only about 20 per cent of all carbon
locked away in global peatlands.1 The largest volumes are
stored in the northernmost areas of our planet, with thenorthern circumpolar region holding almost half of the world’s
soil organic carbon, largely in the form of permanently frozen
peat.2-5

temperatures for at least two consecutive years. Arctic
and subarctic peatlands exist within the permafrost zones
of Canada, Denmark/Greenland, Finland, Norway, Russia,
Sweden and the United States. Permafrost peatlands with apeat layer thicker than 40 centimetres span over 1.4 million
square kilometres, and an even larger area has shallower
peat.3,6-8 Extensive permafrost peat deposits can also be found
far outside the Arctic and subarctic regions, for instancein Mongolia and on the Qinghai-Tibetan plateau, where
mountain ranges prevent warm oceanic air from moving
inland, and winter temperatures are very low.9,10

Much of the ground in the northern hemisphere freezes
and thaws seasonally, and some stays frozen all year round.
Underneath roughly 23 million square kilometres of thenorth lies permafrost – ground that remains at sub-zero

Permafrost peatlands are undergoing rapid changes. The
Arctic is now warming twice as fast as the global average.11
In recent decades, the southern permafrost boundaries havereceded northwards by 30 to 80 km, a significant loss incoverage.12-15 The risks associated with permafrost degradation
are that the mobilization and microbial decompositionof previously buried, frozen organic matter could lead tothe release of significant amounts of carbon dioxide andmethane, which could, in turn, strongly reinforce global
warming.16-19 Widespread permafrost degradation would also
have enormous direct impacts on the regions’ ecosystems,
hydrology and infrastructure.
Although permafrost has been intensively studied for overa century, more research on its distribution, characteristics
and dynamics is critically needed to better understand how it
responds to climate change and human disturbance.20 In thecase of peatlands with permafrost, knowledge is even moreincomplete. The way in which permafrost peatlands respondto a warming climate and their collective role in global climatechange are neither clearly understood nor straightforward,
as the interaction of permafrost, ecosystems and climate isextremely complex.20-22 For example, although frozen (dry)and thawed (wet) peatland sites may have similar carbonsequestration rates and act as a carbon sink, they usually havetotally different greenhouse-gas flux characteristics and may
act as a net source of emissions.23-25 Moreover, frozen andthawed peatland sites could also rapidly alternate over timeand space.23,26
Permafrost thaw is seen as one of the most important “tipping
elements” that could precipitate a runaway greenhouseeffect, or an uncontrollable “Hothouse Earth”.27 To avoid sucha destructive scenario, it is critical that the world’s permafrost
and its peatlands stay frozen and retain their carbon deposits.

Peatlands and permafrost: the role of peat, plants and water
Peatlands are characterized by a thick layer of dead plant remains, or peat. The water-saturated, oxygen-free andpermafrost conditions prevent peat from full decay and allow it to accumulate over thousands of years. The thermal
conductivity of peat is very low when dry, but 5 times higher when wet, and 25 times higher when frozen. The intricate
relationships between peat, vegetation, water and ice maintain the delicate balance of permafrost peatlands.
The
removal of
shrubs leads tomore solar heat
input, permafrost
collapse and wetter
conditions

Vegetation
is important
for the heatbalance ofthe soilA moss layer
has similar
properties to peat
and may cool theunderlying soil
considerably
Palsa

Palsa
Peat

Lake
Discontinuous permafrost
Continuous permafrost

Open water
accumulates
summer heat
and acts as aheat source inwinter, affecting
the distributionof permafrost

Unfrozen groundIn summer, dry peat obstructs heat inflow, butwhen wet and frozen, its properties facilitate
the penetration of winter cold into the soil.
This resulting cold pump creates andconserves permafrost under conditions inwhich it otherwise could not exist.

Cold ice expands byattracting and freezing
nearby water, leading
to drier conditions,changes in vegetationand the formation of
ice-rich peat mounds
or palsas

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Without flowing
water, permafrost
degrades very slowly
and may persist at
depth for long periods
even after superficial
disturbancePeat keeps
the underlying
permafrost effectively
insulated fromtemperature variations
that could inducea thaw

Trees, shrubs and lichens, which
grow better in warmer and drier
conditions, can also create colder
soil conditions: trees and shrubs
absorb incoming light and heat,
whereas light-coloured lichensreflect sunlight39

PERMAFROST PEATLANDS: LOSING GROUND IN A WARMING WORLD

Each year of the past decade has been warmer in the Arctic
than the warmest year of the 20th century.15 Globally,
permafrost temperatures have continued to rise in recent
decades. The greatest increments in annual mean permafrost
temperatures have been observed in the coldest parts of the
Arctic, whereas the increases have been much less in “warmer”
permafrost and in discontinuous permafrost zones. In somelocations, permafrost temperatures have dropped marginallybecause of recent cold winters.15,28
As temperatures rise, the thawing of ice-rich permafrost or
the melting of ground ice leads to distinctive depressions in
the landscape, known as thermokarst. Over the past decades,
thermokarst formation in peatlands seems to have accelerated
in the discontinuous permafrost zones.29-31 However, across the
Arctic, long-term observations do not suggest uniform trends
in thermokarst development attributable to global warming.15
When formerly frozen soil collapses due to a thaw, thesubsidence allows the formation of small, new bodies of waterthat can later evolve into lakes. The formation of thermokarst
lakes, in turn, accelerates permafrost thaw even faster anddeeper.19 The spread of these lakes, on the other hand, could
Video: Permafrost – what is it?

Video link: https://www.youtube.com/watch?v=lxixy1u8GjY
Photo: Freshly-drilled core sample of permafrost, Pokhodsk, Russia
Photo credit: Hans Joosten

40© Alfred-Wegener-Institut, HelmholtzZentrum für Polar und Meeresforschung

Arctic (60–90°N) and global annual surface air temperature
relative to the 1981–2010 average value+2
Temperature Anomaly (˚C)

Thawing permafrost, decaying peat andcomplex interplays

ArcticGlobal

+1
0
-1
-2
1900

1920

1940

1960

1980

2000

Year

Source: Adapted from the Arctic Report Card 2018 of the US National Oceanic and Atmospheric Administration11

also increase the connectivity of drainage networks, supportinglake drainage, vegetation regrowth, peat formation and there-establishment of permafrost.32-37 These contrasting dynamics
illustrate the greater need for a better understanding ofpotential impacts of the warming trend.
Climate change and elevated temperatures have dramaticallyincreased the incidence of wildfires in the Arctic, withblazes spreading into tundra and forest–tundra boundary
regions. Fuelled by underlying peat deposits, fires releasevast amounts of carbon, destroy vegetation and insulating
soil layers, and decrease ground albedo, or light reflectance,
leading to increased sensitivity to climate change andwidespread thermokarst development.38-44 Even under themost conservative scenarios, the combined impacts of warmer
temperatures and wildfires are predicted to be especiallysevere in discontinuous permafrost zones, with climate
conditions becoming unfavourable to permafrost altogether.31
This could cause changes in the types of vegetation and its
productivity, which could in turn result in larger and more
frequent wildfires.45,46
Another effect of increased warming due to climate change
is that permafrost thaw could release significant amounts ofmethane, a potent greenhouse gas, into the environment.
Although there is large variability in Arctic methane-emission
estimates, current global climate projection models seem tosuggest only slight increases in methane emissions from thenorthern permafrost region.47,48 However, most models do notinclude an adequate representation of thaw processes.8

C

C
C

C

account for a small fraction of total carbon release from newly
thawed permafrost, yet it could cause up to 40 per cent of
the additional warming effect attributable to newly thawed
permafrost.49

Thermokarst

Photo credit: Hans Joosten

Thermokarst is a landscape feature that results fromthe melting of ground ice in regions with underlying
permafrost, causing subsidence at the surface. Typicalthermokarst formations include thermokarst lakes,
sinkholes, pits and troughs in polygonal terrain.56,57
Thermokarst is widespread in discontinuous permafrost
zones.58,59 It is also frequently found in the much colder
zones of continuous permafrost, where ice wedges cause
permafrost instability.60,61

Climate change is only one of many factors directly
influencing the changes in permafrost peatlands. Any
disturbance to the surface soil can lead to permafrost
degradation, including natural processes such as forestor tundra fires, and anthropogenic disturbances, suchas industrial and urban infrastructure development andconstruction activity, mining, tourism, and agriculture.50,51
These many forms of development in permafrost peatlands
often disregard the unique features of the areas, causing
landscape fragmentation and disruption of the water
cycle.14,52 In Russia, 15 per cent of the tundra territory has
been destroyed by transport activities, resulting in permafrost
thawing, erosion, subsidence and thermokarst development.53
About 45 per cent of the oil and natural gas production fields
in the Russian Arctic are located in the most ecologicallysensitive areas, often in peatlands, including the Pechora
region, Polar Urals and north-west and central Siberia.54,55 The
rising demand for natural resources and increased accessibility
to frozen regions due to warmer conditions may in the future
result in more industrial and infrastructural activity, escalating
disturbance to peatlands and permafrost. The resulting
changes will also impact indigenous peoples who havetraditionally depended on the use of land such as peatlands
for food, reindeer, game, and fish.14

Water accumulating due to thermokarst initially enhances
heat gain and degradation in a positive feedback.
Conversely, vegetation growth and the accumulationof organic matter gradually limits further downwardthawing. Because of new and rapid peat accumulationin thermokarst depressions, the thawing of permafrost
does not necessarily convert the peatland into a carbon
source.22,23,62 However, wet soil conditions will likely cause
the release of methane.
A recent modelling study assessed the long-term climaticconsequences of permafrost degradation by considering
the abrupt thaw processes relating to recently formed
thermokarst lakes. The result suggested that within thiscentury, carbon release in the form of methane (CH4) may

Thawing and collapse of permafrost in Mongolia

Photo credit: Hans Joosten

UN ENVIRONMENT FRONTIERS 2018/19 REPORTC41

PERMAFROST PEATLANDS: LOSING GROUND IN A WARMING WORLDDistribution of
Permafrost
Peatlands

Permafrost
is degrading. The
southern boundaries
have retreatednorthward by
30-80 km in recent
decades

Underneath
25% ofthe northernhemisphere lies
permafrost

Peatlands span vast areas in the permafrost zones.
At least 1.4 million km2 of permafrost peatlands
have a peat layer thicker than 40 cm, anda much larger area has shallower peat.

Permafrost peat deposits are also
found in Mongolia and on
the Qinghai-Tibetan Plateau

Permafrost
IsolatedSporadic

42

Peatlands

Discontinuous> 50% coverContinuous

20-50% cover

Geospatial data sources:
Peatlands data provided by Greifswald Mire Centre, Greifswald, Germany
Permafrost data provided by Alfred Wegener Institute, Helmholtz Center
for Polar and Marine Research (AWI), Bremerhaven, Germany90

Arctic
temperatures
are rising twice as
fast as global
average

Peatlands
are thelargest longterm stores oforganic carbon
of all terrestrial
ecosystems

Climatemodelssuggest 35%
near-surface
permafrost
loss by2050

Shrubs, trees
and lichens can keep
soil cooler by absorbing or
reflecting sunlight.
Removal of the protective
vegetation can cause
rapid degradation of
permafrost.

Fire removes insulating
vegetation, peat and soil
layers, making peatland more
vulnerable to climate change

When peat is nolonger frozen as aresult of permafrost thaw,
microbial decomposers
become active andbreakdown organic
materials, causing
emissions of
CO2 and CH4

Experts expect
the permafrost
regions to becomea carbon sourceby 2100

Deeper water bodies accumulate
heat in summer and become a heatsource in winter, influencing the
local distribution of permafrost

Circumpolar soils
hold 50% of theworld’s soil carbon,
and this carbon is largely
stored in peatlands
and often conserved
as permafrostIn
the absenceof moving surface
or groundwater,
permafrost degrades
very slowly and canpersist at depth fora long time

Permafrost soils including peat
deposits contain twice as muchmercury as the amounts foundin the rest of global soils, theatmosphere, and oceans combined

Permafrost
thaw could releasesignificant amountsof mercury into
the environment

Thermokarst
is a distinctive
depression in thelandscape as aresult of permafrost
thaw or meltingof ground ice
Thermokarst
is widespread in
the zone of
discontinuous
permafrost

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Peatlands are areas witha layer of dead plant materials(peat) at the surface. The
water-saturated and oxygen-free
conditions prevent peat fromfully decomposing.

Arctic warming
has increased fire
activity in tundra andforest–tundra regions
causing significant
reductions insoil carbon

The combined
impact of climate
warming andwildfire is more
severe in the zone of
discontinuous
permafrost

Soil organic carbon may be lostin different forms: as gases – CO2
or CH4 – emitted back into theatmosphere, or as dissolved organiccarbon or particulate organiccarbon transported into rivers

43

PERMAFROST PEATLANDS: LOSING GROUND IN A WARMING WORLD

Growing awareness of permafrost peatlands
For more than a century and increasingly over the last
decades, permafrost regions have been the subject of
research and technology development to address their
distinctive scientific and engineering challenges. Despite
the efforts of the International Permafrost Association and
the Global Terrestrial Network for Permafrost, large gaps inregion- and habitat-specific knowledge remain, not least due
to extreme climatic conditions, limited accessibility and acomplex geopolitical setting. A recent review indicated that
30 per cent of all citations in scientific literature related to field
experiments in the Arctic are primarily derived from the direct
surroundings of just two research stations: Toolik Lake in
Alaska, USA and Abisko in Sweden.63 This could bias scientificconsensus and lead to inaccurate predictions of the impacts ofclimate change in the Arctic.
1949

1972

With the growing awareness of climate change and Arctic ice
melt, recent assessments are increasingly trying to encompass
aspects such as social-ecological change, regime shifts, andthe role of human action in adaptation and transformation.64.65
Large-scale research projects are being developed to address
the implications of permafrost thaw and degradation. These
include the Arctic Development and Adaptation to Permafrost
in Transition (ADAPT) initiative, which collaborates with 15
laboratories across Canada and other groups of researchers
to develop an integrated Earth systems science framework in
the Canadian Arctic. Dedicated laws such as Ontario’s 2010
Far North Act are combining with new planning initiatives
to open up and protect the Far North through a land-use
planning process in consultation with First Nations.66
The Arctic Council is an example of strong international
cooperation that has been especially instrumental in

1979

2010

2013

Progression of thermokarst development due to permafrost thaw between 1949 and 2013 in a study site located in Prudhoe Bay, Alaska, United States.
The white line is the Spine Road constructed in 1969.
Source: Walker et al. (2014) 52

44

generating and increasing knowledge for national andinternational policymaking, such as with its 2017 report onsnow, water, ice and permafrost in the Arctic.15,67 While itis recognized that Arctic states play a key role as stewardsof the region, efforts by other actors in the protection andawareness of permafrost peatlands are also needed. A numberof international organizations, such as the Intergovernmental
Panel on Climate Change – through its IPCC Special Report on
the Ocean and Cryosphere in a Changing Climate, the World
Meteorological Organization, and the International Science
Council through the International Arctic Science Committee,
have become increasingly engaged, helping to raiseawareness and understanding of the implications of changes
in the Arctic.

Permafrost thaw has led to thermokarst formation in peatlands near
Naryan-Mar, Nenets autonomous region, Russia
Photo credit: Hans Joosten

C
C

C
C

C

Ontario’s Far North Act and the role of First Nations in protecting permafrost peatlands

Between 50-57 °N and 79-94 °W lies the Far North of Ontario, Canada – a dynamic landscape hosting arctic, boreal, andtemperate biomes. Here, peatlands dominate the landscape, covering 47 per cent or 21 million hectares of the Far North
area, and storing about 36 gigatons of carbon as peat.68 This is equivalent to a quarter of the carbon stored in all of Canada’s
peatlands.

As required by the Act, the Far North land use strategy sets out to help prepare community-based land-use plans while
integrating issues beyond the scope of individual planning areas, such as indigenous knowledge. Four objectives outlined in
the strategy include:
1. A significant role for First Nations in planning.
2. The protection of ecological systems and areas of cultural value in the Far North by including at least 225,000 km2 of theregion in an interconnected network of protected areas designated in community-based land-use plans.
3. The maintenance of biological diversity, ecological processes and functions, including the storage and sequestration ofcarbon in the Far North.
4. Enabling sustainable economic development that benefits the First Nations.
The strategy was planned for completion by 2016, but the process is still ongoing, led by interested First Nations working with
the Ontario Ministry of Natural Resources and Forestry. Some community-based land-use plans have been approved, somedrafted, while others are underway and some have not yet started.70 Although progress is being made, uncertainty remains
on how to achieve some of the Act’s objectives, including in areas of governance, and particularly in scientific knowledge. It isimperative to understand how climate change affects carbon sequestration and storage in the Far North peatlands, as well as
the related ecological processes, in order to develop appropriate policy and management responses.

UN ENVIRONMENT FRONTIERS 2018/19 REPORTAssented to in October 2010, Ontario’s Far North Act recognizes the significant role of the Far North in carbon storage andsequestration capacity, and provides for community-based land-use planning as a strategy to fight climate change.66,69 The
Act centres around the significant role of First Nations – aboriginal peoples in Canada who are not Métis or Inuit – in land-use
planning that includes cultural, social, ecological and economic considerations.

45

PERMAFROST PEATLANDS: LOSING GROUND IN A WARMING WORLD

Knowledge priorities and network expansion
There remains a great deal of uncertainty about how fast
permafrost peatlands will change and what the impacts of
those changes will be, both locally and globally. International
cooperation is required to fund further research in the longterm and devise workable strategies to reduce vulnerabilities.
Nations need to collaborate on a range of implementablemeasures that acknowledge and apply traditional and local
knowledge, facilitate engagement with stakeholders, anddevelop effective observation networks.15 At the same time,
public outreach and education concerning the risks, likely
impacts and potential adaptation options will be key todeveloping informed governance and policy.
Although there is an existing network of observation stations
providing information on general trends in permafrostchange, the spatial distribution of sites is very uneven. In
particular, there are large gaps in the network across thecentral Canadian and central Siberian Arctic, Greenland,
Russian Far North-East, Tibetan Plateau and subarctic
region.30,63 The timely assessment of the global status of

permafrost requires the expansion of existing research
networks to a more comprehensive monitoring network.
This extended network would optimally be designed to beuser-friendly for all stakeholders, from climate scientists to
the general public, and would include the use of standardized
measurements and easily accessible databases.15,64 Countries
with extensive permafrost zones would benefit frompreparing adaptation plans that assess the potential risks andinclude mitigation strategies for the damage and costs ofpermafrost degradation.64
Permafrost peatlands as carbon hotspots represent a special,highly diverse and dynamic environment that encompasses
complex relationships between soil carbon, hydrology,
permafrost, vegetation, and people. The major knowledge
gaps lie in the limited understanding of how the processes
interrelate and in the insufficiency of current studies andmodels. More research is required on the precise location of
permafrost peatlands, how they are changing, and what theirrelease potential is. Climate models need to include carbon
emissions from the mobilization of permafrost carbon. To
better characterize the response and feedback of permafrost
peatlands to climate change, it will be critical to advancebeyond single-disciplinary investigations. This will requireVideo: Restoring peatlands in Russia for fire 		
prevention and climate change mitigation

Satellite image taken on 19 July 2016 showing dense smoke overpermafrost peatlands of north-central Russia. Red demarcations indicate
high surface temperatures likely caused by peat fires.
Photo credit: NASA Earth Observatory/Jesse Allen and Joshua Stevens

46

Video link: https://www.youtube.com/watch?v=QZ5qu_nPHYM
Photo: Fire in dwarf birch tundra in Komi Republic, Russia© Wetlands International
Photo credit: Hans Joosten

a move towards an integration of field observations andretrospective – or palaeoenvironmental – studies, remotesensing, and dynamic modelling.22,30 The physical complexityof permafrost peatlands and the significant potential risks of
their degradation and disruption also demand a more holistic
approach to land-use planning and management, requiring
better integrated knowledge for planners and policymakers.

Video: Peatlands – climate regulation
and biodiversity

The Arctic has already begun to change substantially. Even
with the full implementation of the Paris Agreement under theUnited Nations Framework Convention on Climate Change,
it is still likely that by the end of this century the Arctic
environment would be quite different from that of today.15 The
near inevitability of accelerating impacts reinforces the urgent
need for local and regional adaptation strategies targetingthese carbon-dense northern ecosystems. The prudent
management of permafrost peatlands will be key to limiting
greenhouse-gas emissions, reducing human and ecologicalvulnerabilities, and to building longer-term climate resilience.
© Naturstyrelsen
Photo credit: Hans Joosten

Palsa permafrost mire near Noyabrsk, Western Siberia, Russia
Photo credit: Franziska Tanneberger

UN ENVIRONMENT FRONTIERS 2018/19 REPORTVideo link: https://www.youtube.com/watch?v=ZcxZ9gvNfSU
Flat palsas in Komi Republic, Russia

47

PERMAFROST PEATLANDS: LOSING GROUND IN A WARMING WORLD

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Jones, B.M. and Arp, C.D. (2015). Observing a catastrophic thermokarst lakedrainage in Northern Alaska. Permafrost and Periglacial Processes 26, 119–128.
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Van Huissteden, J., Berrittella, C., Parmentier, F.J.W., Mi, Y., Maximov, T.C. andDolman, A.J. (2011). Methane emissions from permafrost thaw lakes limitedby lake drainage. Nature Climate Change 1, 119-123. https://doi.org/10.1038/
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Roach, J., Griffith, B., Verbyla, D. and Jones, J. (2011). Mechanisms influencingchanges in lake area in the Alaskan boreal forest. Global Change Biology 17,2567-2583. https://doi.org/10.1111/j.1365-2486.2011.02446.x

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Jepsen, S.M., Voss, C.I., Walvoord, M.A., Minsley, B.J. and Rover, J. (2013).
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distribution determined from remote sensing of interior Alaska, USA.
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Flannigan, M., Stocks, B., Turetsky, M. and Wotton, M. (2009). Impacts ofclimate change on fire activity and fire management in the circumboreal
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Jones, B.M., Kolden, C.A., Jandt, R., Abatzoglou, J.T., Urban, F. and Arp, C.D.
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Hu, F.S., Higuera, P.E., Walsh, J.E., Chapman, W.L., Duffy, P.A., Brubaker, L.B. etal. (2010). Tundra burning in Alaska: Linkages to climatic change and sea ice

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PERMAFROST PEATLANDS: LOSING GROUND IN A WARMING WORLD
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Vlassova, T. (2002). Human impacts on the tundra–taiga zone dynamics: thecase of the Russian lesotundra. Ambio Special Report, 12, 30–36.

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Instanes, A. (2016). Incorporating climate warming scenarios in coastal
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Shiklomanov, N.I., Streletskiy, D.A., Swales, T.B. and Kokorev, V.A. (2017).
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Jorgenson, T., Shur, Y.L. and Osterkamp, T.E. (2008). Thermokarst in Alaska.
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Kokelj, S.V. and Jorgenson, M.T. (2013). Advances in thermokarst research.
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Jorgenson, M.T., Racine, C.H., Walters, J.C. and Osterkamp, T.E. (2001).
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McLaughlin, J.W. and Webster, K. (2013). Effects of a changing climate on
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Nauta, A.L., Heijmans, M.M.P.D., Blok, D., Limpens, J., Elberling, B., Gallagher, A.
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to a methane source. Nature Climate Change 5, 67-70. https://www.nature.
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THE NITROGEN FIX: FROM NITROGEN CYCLE POLLUTION TO NITROGEN CIRCULAR ECONOMY

Photo credit: oticki / Shutterstock.com

The Nitrogen Fix:

From nitrogen cycle pollution to nitrogen circular economy
The global nitrogen challenge
The UNEP 2014 Year Book highlighted the importance ofexcess reactive nitrogen in the environment.1 Its conclusions
are alarming. This is not just because of the magnitude andcomplexity of nitrogen pollution, but also because so little
progress has been made in reducing it. Few of the solutions
identified have been scaled up, while the world continues topump out nitrogen pollution that contributes significantly todeclines in air quality, deterioration of terrestrial and aquatic
environments, exacerbation of climate change, and depletionof the ozone layer.2-10 These impacts hinder progress toward
the Sustainable Development Goals as they affect humanhealth, resource management, livelihoods and economies.11-15
Yet there are signs of hope. The past four years have seena transformation in approaches to managing nitrogen52

pollution. These include new thinking for both consumption
and production in order to seriously address the nitrogenproblem.16-24
Nitrogen is an extremely abundant element in the Earth’s
atmosphere. In the form of the N2 molecule, nitrogen isharmless, making up 78 per cent of every breath we take. The
two nitrogen atoms are held together by a strong triple bond
(N–––N), making it extremely stable and chemically unreactive.
The planet benefits because N2 allows a safe atmospherein which life can flourish, while avoiding the flammableconsequences of too much oxygen. The environmental
interest in nitrogen focuses on the conversion of N2 into otherchemically reactive forms. For simplicity, scientists refer to allother nitrogen forms as “fixed” or “reactive nitrogen” (Nr).11,25
There are many types of Nr with many different effects –beneficial and harmful – and this is where the complications
arise. Reactive nitrogen is essential for all life on earth.
For example, ammonia (NH3) is the foundation for aminoacids, proteins, enzymes and DNA, and thus central to themetabolism of all life forms. Similarly, nitric oxide (NO) acts
as a key biological signalling compound, while ammonium(NH4+) and nitrate (NO3-) are the major nutrient forms ofnitrogen essential for plant growth. This points to a primary
benefit of Nr compounds in that they help to produce foodand animal feed. Using the Haber-Bosch process of artificial
nitrogen “fixation”, humans have massively scaled up the
manufacture of fertilizers – ammonia, urea and nitrates – tosustain a growing world population.26 In parallel, humans
benefit from the natural biological fixation of N2 to Nr byspecialist bacteria found in soil and associated with the rootsof legume crops.
Against these benefits must be set the numerous lossesof ammonia, nitrate, nitric oxide (NO), nitrous oxide (N2O)

and many other forms of Nr pollution that cause multiple
impacts on the environment. These may occur directly
following fertilizer use, while animal manure, human excreta
and other organic wastes also cause huge losses of Nr to
the environment. Although the fraction of Nr lost to theenvironment from biological nitrogen fixation is thought tobe smaller than from many fertilizers, once excreted fromanimals and humans, both sources contribute to Nr pollution.
Reactive nitrogen is also yielded as a by-product of humanactivities. For instance, fossil fuel and biomass combustion
processes release NO and NO2, collectively called NOX. While
major efforts have been made to reduce NOX from vehicles
and energy generation, emissions are still escalating in rapidly
developing parts of the world.6,12 Altogether, humans areproducing a cocktail of reactive nitrogen that threatens health,climate and ecosystems, making nitrogen one of the mostimportant pollution issues facing humanity. Yet the scale ofthe problem remains largely unknown and unacknowledged
outside scientific circles.

Different forms of nitrogen in the environment
N
N

N
N
N

N

H
N H
H

O

O

N

O

N

O

N

O

O
-

Di-Nitrogen (N2)

Ammonia (NH3)

Nitric Oxide (NO) andNitrogen Dioxide (NO2)

Nitrate (NO3 )Nitrous Oxide (N2O)

SourceN2 makes up 78% of air
we breathe

SourceManure, urine, fertilizers andbiomass burning

SourceCombustion from transport,
industry and energy sector.
NO and NO2 are collectively
known as NOX.

SourceWastewater, agriculture andoxidation of NOX

SourceAgriculture, industry
and combustion

Benefits
N2 maintains stable
atmosphere for life on Earth.
It makes the sky appear blue.

Benefits
NH3 is the foundation foramino acids, protein andenzymes. Ammonia iscommon used as fertilizer.

Benefits
NO is essential in humanphysiology. NO2 has
no known benefit.

Benefits
Widely used in fertilizers andexplosives

Benefits
Used in rocket propellants
and in medical procedure
as laughing gas

Effects
N2 is harmless andchemically unreactive

Effects
NH3 causes eutrophication
and affects biodiversity. It
forms particulate matter in air
which affects health.

Effects
NO and NO2 (or NOX) aremajor air pollutants,
causing heart disease
and respiratory illness.

Effects
It forms particulate matterin air and affects health.
In water, it causes
eutrophication.

Effects
N2O is a greenhousegas–300 times more
powerful than CO2.
It also causes depletionof stratospheric ozone.

UN ENVIRONMENT FRONTIERS 2018/19 REPORTN

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THE NITROGEN FIX: FROM NITROGEN CYCLE POLLUTION TO NITROGEN CIRCULAR ECONOMY

The knowns and known-unknowns of nitrogen
Both the cycling of nitrogen compounds and the humanimpacts are well documented.4,12,27,28 Yet compared withthe role of carbon in climate change, there has been little
public debate about the need to take action on nitrogen. The
increased levels of Nr compounds in the air above cities andabove agricultural areas are measurable, for example as NOX,
NH3 and fine particulate matter, or PM2.5. Elevated levels ofNO3- in groundwater under agricultural areas in several regions
around the world and in rivers downstream of cities with little
or no sewage treatment are equally quantifiable. Atmosphericconcentrations of the greenhouse gas N2O are accumulating
at an accelerating rate. The clear message is that humans are
massively altering the global nitrogen cycle, causing multiple
forms of pollution and impacts, making Nr a key pollutant totackle, from local to global scales.22
The European Nitrogen Assessment identified five key threatsof nitrogen pollution: water quality, air quality, greenhouse-gas balance, ecosystems and biodiversity, and soil quality.4 It
highlighted that nitrogen pollution itself is not a new problem,
but that nitrogen management needs to be part of the solution
to many existing environmental problems. Concerning foodproduction, global nitrogen use is extremely inefficient.20,29
Considering the whole food chain, only around 20 per cent of
the Nr added in farming ends up in human food.11,17 This implies
that a worrying 80 per cent is wasted as pollution and N2 tothe environment, demonstrating that Nr pollution represents a
massive loss of valuable resources.
While past efforts have focused on a fragmented approach
between different Nr forms, considering them all together has
several advantages. First, it allows us to start looking at thesynergies and trade-offs between Nr benefits and different typesof Nr pollution. Secondly, and just as important, it encourages
us to quantify the societal cost of all the impacts of nitrogen
pollution in order to inform policy and the general public.13,30
Cost estimates can help guide mitigation policies, however,
the true cost of Nr pollution is really a known-unknown, since

The average concentration of nitrogen dioxide (NO2) in the troposphere in 2014

0

1
15

2

3

4

5
2

10 molescules/cm

NO2 is a gas emitted mainly from cars, power plants and industrial activity. NO2 and other NOx react with other air pollutants to form harmful ground-levelozone, acid rain and particulate matter.
Photo credit: NASA Goddard Space Flight Center

54Video: Saving the Great Lakes from toxic algae© PBS NewsHour

impacts tend to be fundamentally “non-commensurable”, thatis, it is hard to find a common measure. Comparing health,ecosystem and climate costs is like trying to compare apples
and oranges. The available estimates, based on the willingnessof people to reduce the risks of Nr pollution, or estimates ofcosts to ecosystems and healthcare services, are neverthelessinformative and indicate a global cost of around US$340
billion to US$3,400 billion annually.11
A much simpler calculation, however, can be even more
powerful. Globally, around 200 million tonnes of Nr resource
is lost to the environment per year as Nr and N2.11,28 If we
multiply this by a nominal fertilizer price of US$1 per kg N,
then the total amounts to a cash loss of around US$200
billion per year. This represents a strong motivation for action.
This message is also relevant for areas with too little Nr, suchas sub-Saharan Africa, where reducing Nr pollution would
help limited available Nr sources to go further in supportingfood production.31 The conversion of Nr compounds back to
N2 (termed “denitrification”) does not provide a safe way to
avoid Nr pollution. Rather, it implies a need for fresh Nr inputs,
tending to increase pollution. Indeed, all N2 and Nr losses need
to be reduced if economy-wide nitrogen use efficiency (NUE)
is to be increased.

Algal bloom (shown in milky green) in the west of Lake Erie between
Canada and the United States on 3 August 2014. Lake Erie’s frequent algal
blooms are caused by nitrogen and phosphorus loading from agriculturalrunoff of fertilizers and manure, municipal wastewater effluent andatmospheric deposition.
Photo credit: Jeff Schmaltz / NASA Goddard Space Flight CenterVideo: Human fingerprint on global air quality

Video link: https://www.youtube.com/watch?time_continue=7&v=aMnDoXuTGS4
Photo credit: Doin / Shutterstock.com© NASA Goddard
Space Flight Center

UN ENVIRONMENT FRONTIERS 2018/19 REPORTVideo link: https://www.youtube.com/watch?v=b6JzL4NG26k
Photo: Algal bloom in Pelee Island in the southeast of Lake Erie
Photo Credit: Tom Archer / Michigan Sea Grant (www.miseagrant.umich.edu)

55

THE NITROGEN FIX: FROM NITROGEN CYCLE POLLUTION TO NITROGEN CIRCULAR ECONOMY

Innovations
and Risks
Fossilfuel
combustions in the transport, energy and industrial sectors
High temperature combustion ofcoal, petroleum and natural gas releasesa large amount of Nr in the form of NO andNO2, collectively known as NOx

The transport
sectorcontributes to morethan 65% of NOxemissions

Fossil fuelcombustion is
responsible for
13% of theanthropogenic
fixation of
N2 to Nr

Fertilizer
manufacture
accounts for 63% of
the anthropogenic
fixation of N2 to Nr

Fertilizer manufacture
The Haber-Bosch process was invented
more than 100 years ago to meet thegrowing need for mass industrial
production of Nr fertilizers andnitrogen-based explosives. Like thenatural nitrogen fixation by bacteria,
it artificially fixes
atmospheric N2 into
ammonia (NH3).

Biological nitrogen fixation in crop cultivation
In nature, N2 canbe converted
into Nr throughlightning andbiologicalnitrogen fixation
by nitrogenfixing bacteria

N2

N2

+

Nitrogen fixation

N2

N2

NH4

-

NO2

56

Biologicalnitrogen fixation incrop production is
responsible for 24%of the conversion
of N2 into Nr-

NO3 Denitrification
Unlike sewage and wastewater, a large amountof food waste is avoidable

Waste
In addition to the food production
and combustion of fossil fuels
being key to mitigating Nremissions, the role of waste
management is also significant
in preventing more Nr fromcascading through theenvironment

Nr can also be biologicallyconverted back to N2 throughthe denitrification processby anaerobic bacteria. Thesenatural processes keep a balanced
cycle of nitrogen, but increased
cultivation of nitrogen-fixing
crops such as legumes has
significantly added Nr inputs andlosses into the environment.

Sewage,wastewaterand food waste
contain proteins.
About 16% ofprotein isnitrogen

Cereals, fruits,
vegetables, roots
and tubers make up
the largest volumesof food losses
and waste

Every year
about1/3 of thefood produced
globally for humanconsumption is lostor wastedNearly 80% of
anthropogenic
N2O emissions
come fromagriculture

80% of global
Ammonia, NH3,
emission comesfrom humanactivities, largely
fertilizer applications
and animalhusbandry

50% of nitrogen
fertilizers added tofarm fields ends up as
pollution, or iswasted bydenitrificationback to N2

In 2016 theworld used 105 million
metric tons of nitrogen
fertilizers, or theequivalent to 4.2 million
truckloads offertilizers

Long-term
applicationof ammonium-based
fertilizers causes soil
to become acidic,
negatively affecting
crop production

The Nitrogen Cascade78%
of air is N2

Nitrogen is essential for every living organism. It is partof DNA, amino acids, proteins, chlorophylls, enzymes,
vitamins and many other organic compounds.
N2 is abundant but metabolically unusable by livingorganisms except for some microbes. To makenitrogen usable, N2 must be converted into otherforms of nitrogen or reactive nitrogen, Nr.

Ammonia andnitric acid react to form
ammonium nitrate inparticulate matter,increasing risks ofrespiratory andheart disease

Nitrate, NO3from farming can leachdown through soils into
groundwater, affecting thequality of drinking watersupplies and posing
significant risk tohuman healthAmmonia
pollution cause
eutrophication, soil
acidification and direct
toxicity in organisms,
reducing
species richness
and diversity

Nr emissions
can mix with rain
to create nitricacid rain

Nr enrichment
promoteseutrophication,
leading to harmful algal
blooms, dead zones
and biodiversity loss
in freshwater and marine
environments

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Nitrogen
Oxides, NOx, affecturban air quality. Acute andchronic exposures to NO2 arelinked to respiratory andcardiovascular diseases andmortality. Children, the elderly
and persons with asthma arevulnerable to NO2.

Nitrous
Oxide N2O is agreenhouse gas – 300
times more potent thanCO2. It also damages theozone layer

57

THE NITROGEN FIX: FROM NITROGEN CYCLE POLLUTION TO NITROGEN CIRCULAR ECONOMY

Policy fragmentation and circular economy
solutions
Just as nitrogen science has become fragmented between
environmental compartments and Nr forms, the same istrue of nitrogen policies. The impacts of Nr cross multiple
policy domains, such as air pollution, climate, freshwater andmarine policy, biodiversity, health and food security. While
this fragmentation is widely seen in the domestic policies
of many countries, it is equally apparent in the Sustainable
Development Goals (SDGs). Examination of the SDGs and theunderlying indicators shows that nitrogen is relevant almost
everywhere, but almost equally invisible. Only in the proposed
indicator for SDG 14.1 on life below water is a nitrogen-related
indicator currently being developed.32 Proposals to include
NUE or nitrogen losses in the set of SDG indicators have notbeen adopted thus far.20,33
The consequences of this policy fragmentation acrossthe nitrogen cycle can easily be seen in policy trade-offs.
For example, policies to reduce NO3- pollution of waterin the European Union led to the prohibition of manure
application to land in winter “closed periods”. However, thisled to an increase in spring-summer manure application,
which in turn resulted in an increased peak in atmosphericammonia concentrations.34 This temporal effect was only
partly avoided in a few EU countries, by requiring low NH3emission application of manure.35 Another example concerns
the recommendation to bring cattle indoors to reduceclimate-relevant emissions of N2O. However, even with thebest technical measures to moderate emissions, this would
generally lead to increased NH3 emissions.36 Such trade-offs
are also relevant for combustion sources. For example, theintroduction of catalysts to reduce NOX emissions in the 1990s
increased N2O and NH3 emissions.
These examples illustrate the urgent need to bring nitrogenscience and policies together across multiple threats.11,30,37
For example, the Chinese Government’s 2015 “Action Planfor the Zero Increase of Fertilizer Use” aimed to prevent thegrowth in synthetic fertilizer use by 2020 without reducing
food production, which would limit all forms of Nr pollution.
It has been suggested that a next step should focus onsocioeconomic barriers associated with farm size, innovationand information transfer.38

58

Nitrogen, nutrients and the circular economy
The Circular Economy Package adopted by the European
Union in 2015 aims to maximize the efficiency of
resource use in all steps of the value chain – production,
consumption, waste management and recycling of
secondary raw materials.42,43 The plan recognizes the
management and trade of organic and waste-based
fertilizers as key in the recovery and recycling of bionutrients, such as nitrogen and phosphorus, back in the EU’s
economy. The new regulation encourages the sustainable
and innovative production of organic fertilizers using
domestically available bio-waste, animal by-products suchas dried or digested manure, and other agricultural residues.
Currently, only 5 per cent of organic waste material isrecycled and applied as fertilizer within the EU. Enabling freecross-border movement of the bio-based fertilizers would
lead to the creation of a new market space and supply chain
for secondary raw materials within the EU. It is estimatedthat around 120,000 jobs would be created as a result. The
recovery of nitrogen from bio-waste is expected to reduceor substitute the need for synthetic or inorganic nitrogen
fertilizers, the production of which has high carbon andenergy footprints. At the same time, this will further help toreduce losses of reactive nitrogen into the environment.
Mobilization of the circular economy for nitrogen and othernutrients starts on farms, where reducing losses allows amore effective delivery of nutrients to support crop growth.
A major need here is the provision of practical tools to guidefarmers on reducing nitrogen inputs to account for reduced
nitrogen pollution losses, achieved by implementing
mitigation methods. These should be supported byappropriate soil testing to give farmers confidence infine-tuning nutrient levels.
However, there is also massive potential for scaling up
reuse of nitrogen and other nutrients for the production ofvalue-added, marketable products. Just as major investment
is transforming society for a “low-carbon economy” (e.g.
through renewable energy sources), the value of nitrogen
implies a major economic opportunity through investment
toward a “nitrogen circular economy”.

Regional consumptions of all types of nitrogen
fertilizers in 1980 and 2016 (in million metric tonnes)

4.7

3.6

1980
Year
2016

21.8

9.4
5.3

2.8
9.2

11.8
14.2

0.3

1.3

2

3.3

15

13

34

11.7

Western andCentral Europe

AfricaWest Asia

East Asia

Eastern Europe
and Central Asia

North America

Latin America andthe Caribbean

South Asia

Oceania

In India, a financial perspective also informs the government’s
policy from 2016 requiring all urea fertilizer to be coatedwith neem oil, in order to reduce both environmental lossesof Nr and financial leakage of the subsidy to non-agriculturalurea applications. The same principle underlies the Indian
Prime Minister’s call in November 2017 for farmers to halve
fertilizer use by 2020, as well as governmental backing for
Zero Budget Natural Farming (ZBNF) in some Indian states.
The ZBNF movement focuses on avoiding costly external
inputs of fertilizers and pesticides, helping farmers avoid
debt, while promoting organic opportunities to improve soilorganic matter, soil biology and fertility. In Andra Pradesh, a
rapid upscaling of ZBNF to thousands of enthusiastic farmers
is being supported by partnership between BNP Paribas,
United Nations Environment Programme (UNEP) and theWorld Agroforestry Centre ICRAF, through the Sustainable
India Finance Facility (SIFF). This innovative approach is basedon loans to support investment and expansion being paidback by the government, since much less fertilizer subsidy will
be needed when the fertilizer use reduces.40,41

UN ENVIRONMENT FRONTIERS 2018/19 REPORTThe situation has been very different when it comes tocombustion sources of NOX, since all available technologies,
for instance, catalytic and non-catalytic reduction, focus on
denitrification of NOX back to N2. Yet this represents a massive
loss of resources. Multiplying global NOX emissions by thefertilizer price of Nr would give an annual resource of US$50
billion globally, pointing to the need for technologies torecapture NOX as NO3-.11,39

1.8

Year

It is also easy to envisage transforming the nitrogen cycle inagriculture into a model of the circular economy for nitrogen.
Here improvements in efficiency and reduced losses fromfertilizers, biological nitrogen fixation, urine and dung allow
more of the fresh nitrogen to reach intended food and bioenergy products. At the same time, reprocessing of livestockand human excreta into new fertilizers offers the opportunity
to market recycled fertilizer products.

Data source: International Fertilizer Association (https://www.ifastat.org/databases/plant-nutrition)

59

THE NITROGEN FIX: FROM NITROGEN CYCLE POLLUTION TO NITROGEN CIRCULAR ECONOMY

Towards a holistic international approach fornitrogenVideo: Why fertilizer matters to the environmentand your bottom line

The encouraging news is that a few countries are piloting
more integrated approaches to nitrogen management.
For example, Germany quickly responded to the European
Nitrogen Assessment by working on an integrated nitrogenstrategy.23,44 The difficulty for many countries is that a responseto address nitrogen threats is split across multiple ministries,
making it difficult to coordinate action. For example, in Brazil,
agriculture is still expanding over large areas and the needfor better decoupling of crop and animal production withenvironmental impacts has not been expressly addressed.45
Internationally, the transboundary impacts of Nr also require
clear legislation and policy actions.
The members of the International Nitrogen Initiative (INI)
have given considerable thought to these challenges. The firststep has been to work with the United Nations Environment
Programme to establish a coordinated approach to scientificsupport for international policy development, in the form of
the “International Nitrogen Management System” (INMS).
With the support of the Global Environment Facility and80 partner organisations, INMS is developing guidanceon the management of nitrogen, the integration of flows

Video Link: https://www.youtube.com/watch?v=5TzzPOy1T3g
Photo credit: Visual Generation / Shutterstock.com© Environmental Defense Fundand impacts, cost-benefit valuation, and future nitrogenscenarios. INMS is also developing regional multi-country
demonstrations to show how holistic nitrogen management
can help. A key outcome will be the first Global Nitrogen
Assessment, due for publication in 2022.
The next challenge is to develop a more coherent policy
framework for the nitrogen cycle. The need for this canclearly be seen in the multitude of the United Nations
Environment Assembly resolutions relevant to nitrogen: 2/6(Paris Agreement), 2/7 (Chemicals & Waste), 2/8 (Sustainable
Consumption & Production), 2/9 (Food Waste), 2/10 (Oceans),
2/12 (Coral Reefs), 2/24 (Land Degradation), 3/4 (Environment& Health), 3/6 (Soil), 3/8 (Air Quality) and 3/10 (Water
Pollution).46,47 The point is well made by Resolution 3/8, which
encourages governments “to take advantage of synergistic
effects of efficient nitrogen management on reducing air,marine and water pollution”.

Video: Air pollution from agriculture

Recent discussions in the scientific and policy communities
have explored how to coordinate nitrogen policy engagement
more effectively.48 Some possibilities include:
Video Link: https://www.youtube.com/watch?v=07P_wXTTusI
Photo credit: gillmar / Shutterstock.com

60© European UnionAt present the Coordination Mechanism is lacking, which
limits the extent to which the existing MEAs learn from eachother, while also being inefficient in requiring that INMS
work individually with multiple MEAs. The Coordination
Mechanism would serve to actively engage Member States
and relevant MEAs. The Major Groups and Stakeholders to
the United Nations Environment Programme already facilitate
involvement of business and civil society. It should be notedthat Option 4 remains just that – an option. It is for national
goverments to discuss which approach would be the mostagile, efficient and cost-effective.
Nevertheless, this discussion points to another benefit. It is
becoming increasingly obvious that global society needs aholistic approach for nitrogen science and policy. First, themulti-source, multi-sector perspective allows synergies andtrade-offs to be considered. This would benefit agriculture
and industry by providing a more coherent basis for businessdecision-making. Secondly, the holistic approach provides
the foundation to develop the circular economy perspectivethat is vital to mobilizing change. In addition to these,such an approach for nitrogen becomes an illustration of
how future environmental policy could coordinate more
effectively between issues. As the United Nations Environment
Programme works towards its strategy for a “Pollution-Free
Planet”, the lessons are likely to be all the more important
across the realms of interacting pollution issues.

Inter-convention Nitrogen Coordination Mechanism

Air Quality

MarineClimateStratosphere

Inter-convention
Nitrogen
Coordination
Mechanism

Montreal Protocol

Biodiversity

Providing science support

Video: The agricultural ammonia challengeVideo Link: https://www.youtube.com/watch?v=y0lG5mOWyAs
Photo credit: Mark Sutton© CAFREtv

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Option 1: Nitrogen fragmentation across policy frameworks –the status quo
Option 2: Nitrogen leadership under one existing policy
framework. This provides a challenge to the mandate of eachsince existing Multilateral Environmental Agreements (MEAs)
address only parts of the challenge.
Option 3: A new international convention to address thenitrogen challenge. There is currently little readiness for thisapproach.
Option 4: An “Inter-Convention Nitrogen Coordination
Mechanism”, providing an intergovernmental forum for interinstitutional cooperation on nitrogen, perhaps under the
mandate of the United Nations Environment Assembly.

61

THE NITROGEN FIX: FROM NITROGEN CYCLE POLLUTION TO NITROGEN CIRCULAR ECONOMY

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Bittman, S., Dedina, M., Howard C.M., Oenema, O. and Sutton, M.A. (eds.)(2014). Options for Ammonia Mitigation: Guidance from the UNECE Task Forceon Reactive Nitrogen. Edinburgh: Centre for Ecology and Hydrology. http://
nora.nerc.ac.uk/id/eprint/510206/1/N510206CR.pdf

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

24.

63

THE NITROGEN FIX: FROM NITROGEN CYCLE POLLUTION TO NITROGEN CIRCULAR ECONOMY
Graphic references

49

49.

Zhang, R., Tie, X. and Bond, D.W. (2002). Impacts of anthropogenic and natural
NOx sources over the U.S. on tropospheric chemistry. Proceedings of the
National Academy of Sciences of the United States of America, 100(4), 15051509. https://doi.org/10.1073/pnas.252763799

50.

FAO (2011). Global food losses and food waste – Extent, causes andprevention. Food and Agriculture Organization of the United Nations, Rome.
http://www.fao.org/docrep/014/mb060e/mb060e00.pdf

51.

Ussiri D., Lal R. (2013) Global Sources of Nitrous Oxide. In: Soil Emissionof Nitrous Oxide and its Mitigation. Springer, Dordrecht. https://doi.
org/10.1007/978-94-007-5364-8_5

52.

IFA (2018). International Fertilizer Association database (IFASTAT).
International Fertilizer Association, Paris. https://www.ifastat.org/

53.

Behera, S.N., Sharma, M., Aneja, V.P. and Balasubramanian, R. (2013). Ammonia
in the atmosphere: a review on emission sources, atmospheric chemistry anddeposition on terrestrial bodies. Environmental Science and Pollution Research,
20(11), 8092-8131. https://doi.org/10.1007/s11356-013-2051-9

54.

Field, C.D., Dise, N.B., Payne, R.J., Britton, A.J., Emmett, B.A., Helliwell, R.C.,
Hughes, S, et al. 2014. The Role of Nitrogen Deposition in Widespread Plant
Community Change Across Semi-natural Habitats. Ecosystems, 17, 864-877.
https://doi.org/10.1007/s10021-014-9765-5

55.

Payne, R. J., N. B. Dise, C. J. Stevens, D. J. Gowing, and Begin Partners. 2013.
‘Impact of Nitrogen Deposition at the Species Level’. Proceedings of the
National Academy of Sciences, 110(3): 984–87. https://doi.org/10.1073/
pnas.1214299109

56.

Sheppard, L. J., Leith, I. D., Mizunuma, T., Cape, N., Crossley, A., Leeson, S.,
Sutton, M.A., Dijk, N. and Fowler, D. (2011). Dry deposition of ammonia
gas drives species change faster than wet deposition of ammonium ions:evidence from a long-term field manipulation’. Global Change Biology, 17:3589-3607. https://doi.org/10.1111/j.1365-2486.2011.02478.x

4

4

4

22

50

50

51
53

30

53

35
4

52

22,53

22,
54-56

© Johnny Adolphson/Shutterstock.com

Photo credit: sta / Shutterstock

64

65

UN ENVIRONMENT FRONTIERS 2018/19 REPORTMALADAPTATION TO CLIMATE CHANGE: AVOIDING PITFALLS ON THE EVOLVABILITY PATHWAY

Maladaptation to Climate Change:

The 2011 flood in Bangkok, Thailand
Photo credit: Wutthichai / Shutterstock.com

Avoiding pitfalls on the evolvability pathway
Defining adaptation and maladaptation for the
climate change context
Metaphors are essential to logical thinking. As used forclimate change research and policy, the terms adaptation andmaladaptation originate from evolutionary biology.1 Basically,
genetic mutations spontaneously appear in every generationof a species and a natural selection process, imposed by
the external environment, determines the success or failure
both of those mutations and, as a consequence, of species.
The idea can be applied to bacteria, to plants and animals,
to ecosystems, and even to human behaviour. An importantcharacteristic of successful adaptation is evolvability, thecapacity to continue evolving through further adaptation as
surrounding conditions continue to change.2 In evolutionary
biology, an identifying characteristic of a maladaptation is theabsence of evolvability. It is a dead end.

66

While the origins of adaptation come from evolutionary
biology, adoption of the term for successful human responses
to environmental change started with disaster management.
In that field, all human responses to a disaster are adaptations
to the changed condition, including efforts to abate, or cut off,the source of the disaster.3 The separation of what was calledabatement from adaptation materialized in negotiations
around the United Nations Framework Convention on
Climate Change. One rationale for separating them was thatnegotiators would be distracted from agreement on pathways
for abatement, or mitigation, if adaptation were available
as an easier option.4 Another explanation is that developed
countries would only support efforts that had global
outcomes, such as reduced carbon dioxide in the atmosphere,
rather than locally focused adaptation objectives.5

As climate change negotiations progressed, researchers
examined how and why some adaptation actions go awry,
particularly those actions that waste substantial amountsof human, natural, or financial resources.6 As these opinions
developed, the United Nations Intergovernmental Panel on
Climate Change (IPCC) realized the importance of precise,unambiguous terminology. In 2001, the panel suggested anuanced definition of maladaptation, one that differs from its
usage in biology or behavioural science, in the form of“… an adaptation that does not succeed in reducing
vulnerability but increases it instead”.7 Discussions further
focused on differences between a maladaptation and an
unsuccessful adaptation. An unsuccessful adaptation may
be neutral – it may simply mean an action did not work. But
when an intended adaptation results in increased vulnerability
for other groups and sectors, even in the future, that is amaladaptation.8 At the same time, neither unsuccessful
adaptation nor maladaptation should be confused withsham adaptation: wasteful projects presented as adaptation,such as expensive infrastructure serving only the interests of asmall group, without actually improving resilience or reducing
vulnerability to climate change.9
Maladaptation thinking continues to advance, and one influential
study considered the problem according to the outcomes,
identifying five categories of maladaptation when compared toalternative choices. According to this analysis, maladaptations
are actions that increase greenhouse gas emissions, burden
the most vulnerable disproportionately, incur high opportunity
costs, reduce incentives to adapt, or set paths that limit the
choices available to future generations.8 These parameters
were further articulated and broadened by the IPCC in their2014 Fifth Assessment Report.10 As the concept of adaptation
versus maladaptation becomes clearer and we are better able
to distinguish between them, managing the consequences ofclimate change should become less intimidating.

CENTRAL & SOUTH
AMERICANORTH AMERICAEUROPEARCTICAFRICAANTARCTIC

ASIA

AUSTRALASIASMALL ISLANDSEUROPEASIANORTHAMERICASMALL ISLANDSAUSTRALASIA

Confidence in attribution toclimate changevery low med high verylowhighindicates
confidence range

Observed impacts attributed to climate change forPhysical systems
Biological systems
Human and managed systems
Glaciers, snow, ice
Food production
Terrestrial ecosystems
and/or permafrost
Rivers, lakes, floods,
Livelihoods, health,Wildfire
and/or drought
and/or economics
Coastal erosion
Marine ecosystems
and/or sea level effects
Regional-scale
Outlined symbols / bars = Minor contribution of climate change
impacts
Filled symbols / bars = Major contribution of climate change

Graphic and caption source: The fifth assessment report of the Intergovernmental Panel on Climate Change11

Each filled symbol in the top
panels indicates a class of
systems for which climatechange has played a majorrole in observed changes in atleast one system within thatclass across the respective
region, with the range ofconfidence in attribution
for those region-wide
impacts indicated by thebars. Regional-scale impacts
where climate change has
played a minor role areshown by outlined symbols
in a box in the respective
region. Sub-regional impacts
are indicated with symbols
on the map, placed in theapproximate area of theiroccurrence. The impactedarea can vary from specificlocations to broad areas
such as a major river basin.
Impacts on physical (blue),
biological (green), andhuman (red) systems aredifferentiated by colour.
Absence of climate change
impacts from this figure does
not imply that such impacts
have not occurred.

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Global patterns of observed climate change impacts

67

MALADAPTATION TO CLIMATE CHANGE: AVOIDING PITFALLS ON THE EVOLVABILITY PATHWAY

Maladaptation at scale
In the face of climate change, the concept of maladaptation
has developed from adaptation that does not work to
adaptive actions that damage resources, narrow future
options, worsen the problem for vulnerable populations, orpass on responsibility for solutions to future generations. If an
adaptation action violates sustainable development, social
equity and poverty eradication goals, particularly in the senseof disproportionately burdening the vulnerable, that action
is maladaptive.12 Efforts to avoid maladaptation at larger
scales include research to identify major risks and responsible
adaptation strategies throughout the infrastructure asset
lifecycle that can inform the decisions, and the actions, ofplanners and regulators, designers, constructors, operators,
investors and insurers.13 Threats from maladaptation would
likely escalate as the scale of the action increases. Recallingthe characteristic of evolvability from biology could provide apreliminary screen for maladaptive actions, while prioritizing
preservation of evolvability could forestall serious mistakes.
Limiting future options at the scale of installing aseawall along a domestic property may be considered amaladaptation as it will cause problems and limit options
for neighbours, but such consequences are usually limited
to the local vicinity. However, if a poorly considered action
aggravates the original problems or limits future choices
at a regional or global scale, then it becomes a much
more dangerous maladaptation. At a larger scale, such
maladaptations may not only constrain evolvability, but
could also threaten the resilience of ecosystems, ways oflife, and whole societies. This scale of maladaptive actions,especially those that increase greenhouse gas emissions or
intensify ecosystem degradation, could contribute to thebiogeophysical feedbacks to drive Earth system functions
towards global tipping elements. Many of these tipping
elements are irreversible – such as losses of permafrost, coral
reefs or the Amazon rainforest – and that irreversibility could
usher us over planetary thresholds.14
The IPCC’s Global Warming of 1.5°C report of 2018
identifies multiple requirements for effective adaptation,
demonstrating the importance of climate-smart planningand implementation during the transition to an acceptable

68

Abridgement of maladaptation in
the Fifth Assessment Report of theIntergovernmental Panel on Climate
Change10
In the IPCC’s 2014 Fifth Assessment Report, Working
Group II on the Impacts, Vulnerability and Adaptation(WGII) defined maladaptation as “…actions that may leadto increased risk of adverse climate-related outcomes,
increased vulnerability to climate change, or diminishedwelfare, now or in the future”. It also offered a summary
table of twelve broad categories for maladaptation.
Two of the WGII categories describe actions that
deliberately ignore what is known: failure to anticipate
expected climate change, and failure to take wider
implications into account. Other categories concern
trading off long–term vulnerability for short–terms
benefits, including resource depletion that leads tolater vulnerability; procrastination versus impetuous
action; installation of infrastructure that cannot last;and engaging in moral hazard, where risk-taking is
encouraged by various schemes offering payouts.
Further categories emphasize actions that promote
one group, often an elite, over other groups, warningthat perpetuating privilege may lead to conflict, as
well as actions that ignore local knowledge, traditions
and relationships. However, persisting with traditional
but inappropriate responses is also consideredmaladaptation.
WGII also warns against actions that set pathdependencies that cannot be easily corrected, andactions, especially engineering defences and solutions,that preclude alternative approaches, such as ecosystembased adaptation. Finally, migration may be appropriate
adaptation or maladaptation – or both – depending on
the context and outcome.

temperature increase.15 Avoiding maladaptation is a crucialcomponent of this transition. A number of regional-scalecases, self-identifying or not as climate change response,
can serve as examples for useful inquiry as we face a future
disrupted by climate change. These cases are quick samples
of categories presented by the IPCC’s Fifth Assessment Reportand other distillations of current literature.

Burdening the most vulnerable disproportionately
In some cases, attempts to adapt to changing conditions on
multiple fronts can become maladaptations for particular
population groups. After 2005’s Hurricane Katrina devastated
New Orleans and the surrounding region in the USA, initialplans for new green areas to build urban resilience against
future floods appeared to concentrate acquisition in the
low-lying land that traditionally belonged to poor AfricanAmericans, rather than to other groups.12,19 That particularurban-renewal proposal was not accepted. However, morethan a decade later, studies show that many of the city’s
poorest and most marginalized people never regained whatlittle they did possess, and a significant proportion of themhad to migrate out of the region.12,20

Hurricane Katrina of August 2005 damaged many sections of the levee
system designed to protect the low-lying city of New Orleans against
floods and storm surges. The satellite image shows how a levee breach(yellow circle) allowed flood water from the 17th Street Canal to inundateneighborhoods on the east side of the canals, causing billions of dollars inproperty damage, while the west side remained dry.
Photo credit: Digital Globe (www.digitalglobe.com)

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Balancing short–term demand against planning for long–term resilienceAs an example of the balance between shorter- and longerterm benefits, the Coastal Climate-Resilient Infrastructure
Project in southwest Bangladesh has already been presented
as a case study of a possible maladaptation.16 Conditions
that frame the question are the adaptation benefits over the
next two decades versus the longer-term maladaptive costs
that will dominate by 2050 as rising sea level inundates theregion.16 Potential maladaptive outcomes include complex
issues for migration, both out of and into the region. Investors
expect that the new markets and better roads, bridges,
drainage, and cyclone shelters will encourage the coastal
populations to stay, when perhaps they should migrate inland.
There is a significant likelihood that these facilities will lurenewcomers, possibly including some of Dhaka’s informal
settlement population who have already been displaced byenvironmental disasters.19

69

MALADAPTATION TO CLIMATE CHANGE: AVOIDING PITFALLS ON THE EVOLVABILITY PATHWAY
Water scarcity
Drought

Maladaptation to
Climate Change

The case studies presented in the infographic
demonstrate a range of actions to adapt tochanging climate at different scales. Somecases are maladaptive given the unintended
consequences or will become maladaptationsin the near future. Others are actions taken after
consideration of many factors to avoid
maladaptation.
Maladaptation, defined by the IPCC, is anintended adaptation that instead increases
risk of climate-related damages, increases
vulnerability to climate change, or diminishes
welfare, now or in the future.

Climate change disrupts the hydrological cycle.
Drought will become more intense, frequent andpersistent, threatening all human uses and ecological
functioning. Extended drought conditions lead togroundwater overexploitation and aquifers are
seldom recharged sufficiently once rains arrive.

By 2025,
48% ofglobal landarea will likely
becomedrylands
Recurring droughts
forced 70% of poor Somali
pastoralists into charcoal
production, leading to theclearing of woodlands that
accelerated desertificationand increased
vulnerability

Maldaptations are poor choices amongalternatives, choices that increase greenhousegases, unfairly burden the most vulnerable,
incur unjustifiable costs, reduce incentives toadapt, or limit choices available to future
generations.

Decisionmaking that
ignores science,
wider implications,or likely
consequences

Actionsfavouring one
interest group overanother, laying groundfor future conflictand damage

Unwisetrade-offs: short vslong term benefits,risk vs reward (moral
hazard), too short vs toolong consideration
periodActions that
determine pathdependency and lockin or that eliminate
choices of future
generations
Relocationthat puts
populations in evenmore threatening
conditions

70

Mexico City faces
By 2050, 5.7 billion water scarcity. Exploiting
people could
distant groundwater sources
be living in
is a short-term solution.
water scarce
Actual adaptation invests inareas. Regions
longer-term solutions,are alreadysuch as rainwater
adapting
harvesting andto water scarcity
greywater treatment
through groundwaterand reuse.
exploitation, water
rationing, or
desalination. Suchmeasures may bemaladaptive in thelong term.

Agriculture

Some
Zimbabwean farmers
offset climate uncertainty
by increasing pesticideuse. Too often, beneficial
insects are also eliminated,making conditions
worse.

Persistent climatechange extremes
threaten agricultural
production systems.
Farmers pride
themselves on theiradaptive capacities,
but these extremes arrive
so frequently and persist so
unpredictably that adaptation
becomes a constant concern.

Brazilian double
cropping started after
the introduction ofclimate-specific cultivars.
As rain onset shifts,
these practices become
maladaptive.

HealthAntibiotics
are overused
and misused for bothpreventing and treating
veterinary challenges.
This maladaptation tovector-borne diseases
exacerbates threats ofantibiotic resistance.

Shifting climatic
zones andincreases infrequency andintensity ofclimate extremes
produce healthconsequences. Thisvariability causes crop
losses and expanded ranges
for disease vectors threatening critical plant andanimal species, as well as human populations.
A study showedthat the dung fromcattle treated with antibiotics
emitted more methane
than antibiotic-free dung.
Antibiotic residues
also altered dung
beetles’ gut
microbes.

Florida canalwater levels are used
to recharge and maintainSea levels continue topressure against saltwaterrise globally, threatening intrusion into groundwater.
infrastructure,
Raising canal water levels togroundwater resources,
counter the intrusion
natural barrier islands
inadvertently increases
and coastal communities.
flood threat.
An existential threat to
low-lying nations andsmall island states
extends to a wayof life for millions
of people.

State lawguarantees coastal
access to native Hawaiians
for cultural purposes andsubsistence fishing. Sea level
rise curtails public access,disproportionately affecting thepoor, while development for
private profit persists.

CitiesBy 2050, 70% of the global population will live incities. Around the world, cities already experiencechanging climate in the form of heatwaves,
floods, and adaptation failure. Urban adaptations
can be policies, infrastructure development, or
technological fixes. Remedies seldom benefit all,and they can threaten some marginalized groups.

Warming
temperatures andwater shortages prompted
Melbourne, Australia toincrease air-conditioning
and desalination.
These are maladaptations:b-y increasing GHG emissions,they compound vulnerability
in other systems, sectors
and communities.

Flood

Wildfire

Flooding is one of the most common climate change
impacts experienced worldwide. Flood and water
management systems suited to the past no longer
suffice. As climate continues to change, adaptive
management and wide-ranging stakeholder buy-in
are required to avoid maladaptations.

Globally, the length of the fire season increasedby 19% from 1979 to 2013. Wildfires play importantroles in ecosystems worldwide, but theirdestruction can ruin socioeconomic systems.
In some regions, standard management
strategies exacerbate conditions.

Bangkok’s
metropolitan region isflood-prone due to the lack ofplanning and investment.
Unplanned and uncoordinatedautonomous adaptation
leads to flooding downstream andweakens the entire public drainage
system. In 2011, official responses
to flood protected the wealthy
and burdened vulnerable
groups.
z

After decades offire suppression andfive years of climate–
related drought, Californian
forests are full of wildfire
fuel. With transformation inmind, the State is initiatingprescribed burning tomanage thatthreat.

Some farmers
seek protection fromclimatic extremes throughAround the world, people have adapted toclimate impacts in various ways: water supply
crop insurance thatrethinking, insurance schemes, livelihood strategy
can inhibit further
Insurance policies
changes, voluntary or forced migration, andadaptation
are maladaptive whenresettlement projects. When these well-intentioned
strategies.
they support risky behaviour,
methods are ill-suited to local conditions, or do notsuch as rebuilding in dangerous
consider multiple facets of the issue, vulnerability
locations, or they promote
may increase.
replacement rather than redesign
according to changing conditions.
As climate threats intensify,
insurance may provide a
China’s climate
false sense ofOn
adaptation resettlement
security.
small island
projects offered financial
states, increasingly rising
incentives and improved living
tides wash over coastlines,
standards. They also produced
ruining freshwater resources
disproportionately heavier
and crops. Researchers suggest
burdens on those left behind,labour mobility is thethose already displaced,
best long-term solution toand the poor.
avoid maladaptation
associated withresettlement.

Societal vulnerability

UN ENVIRONMENT FRONTIERS 2018/19 REPORT

Sea level rise

71

MALADAPTATION TO CLIMATE CHANGE: AVOIDING PITFALLS ON THE EVOLVABILITY PATHWAY
Limiting options for future action
Petroleum geologists and engineers developed the capacity
to extract oil and gas from deep earth reservoirs sealed by
the caprock formations.21 Some of the depleted reservoirs
are considered well suited to sequester carbon dioxideover centuries and longer.22 Their suitability is due to ourunderstanding of reservoir permeability and the quality of
the caprock layer that seals the reservoir.21,23 When natural
gas was promoted as a mitigation strategy, that is, a bridging
fuel from coal and oil to renewables, investment grew andthe technology evolved.24 However, there are more problems
with that bridge than had originally been anticipated. Muchof it was related to the evolution of an extraction techniquecalled hydraulic fracturing, or fracking.25,26 This technology
injects a mix of water, sand and chemicals at high pressure todeliberately force fissures and cracks in the reservoir to release
the natural gas. A number of environmental challenges arise
from fracking, including aquifer depletion and contaminationfrom chemicals used in drilling and injection, leakage of
methane into the environment, and increased seismicity.27-30
Further, some suggest that hydraulic fracturing may destroy
the caprock seal that makes the depleted reservoirs valuable
for carbon sequestration.31,32
The IPCC Global Warming of 1.5˚C report details two pathwaysof emission reduction and atmospheric greenhouse gas
limitation that will achieve the goal of keeping the global
average temperature increase above pre-industrial levels
at 1.5˚C. Both pathways rely heavily on the promise of
sequestering carbon in geological formations.15 This hydraulicfracturing industrial policy demonstrates maladaptation on
two fronts: the possibility of foregoing long–term benefits
for short–term gains and locking into path dependency
by damaging future resources. At the same time, fracking
increases greenhouse gas emissions by leaking methane
throughout its production cycle.26,33-35

Hydraulic fracturing or fracking

Drilling
rig
Waste
water

Gas
containers

Discharge and disposal of fracking wastewater
can cause environmental contamination

Fracking wastewater contains salts,heavy metals and naturally occuring
radioactive elements

Water andchemical mixture

Well
Injection of fracking fluids into wells allows
gases and liquids to contaminate aquifer

Flowback fluid carries gas
back up to the surface
Water,
sand andchemicals
injected athigh pressure
to cause fracturesin the shale

72

FracturesGas-rich shale formation

Fractures

Fracking can trigger earthquakes

Water aquiferAvoiding maladaptation in a 1.5°C constrained
futureThe vision offered by the IPCC’s Global Warming of 1.5°C report,
and the wisdom of keeping temperature increase to that mark,suggests that climate change consequences need to be more
widely considered in decisions made by public and private
sector actors, as well as by civil society.14 Rather than narrowing
the concept of maladaptation to unfortunate and complicating
outcomes of actions formally labelled as adaptation, policy
advisers and decision makers at various levels and in a broad
range of institutions could be widening their deliberation to
avoid climate change maladaptations in their planning.
The 1.5°C report also emphasizes the United Nations Agenda
2030 and its sustainable development goals, particularly thoseconcerning equality and equity.14 This vision for meeting theclimate challenges ahead focuses on a future that is worth
living in, that is better than the one experienced by too many
people today. Reducing the root causes of conflicts, wars,
insecurities, poverty, and migrations is a vital component of
this vision. The human species has always adjusted to changing
conditions and we are by nature adaptable creatures. Learning

Photo credit: EcoFlightby trial and error is a dependable methodology to guide ouradaptations. But we are also a species that uses foresightand that plans ahead. We can design our future. Avoiding
maladaptations means we learn not only from our own
errors, but also from those experienced by individuals andcommunities around the world. Using foresight is not limited
to each group’s suspicions, presumptions, or even aspirations,but needs to be based on scientific evidence and realistic
probabilities.
Evidence indicates that maladaptation can be avoided byevaluating all costs and benefits, including co-benefits, forall groups in society, and by being explicit about who thewinners and losers will be, and how the burdens could bebetter shared. Entrenched habits of dismissing the interestsof future generations are not appropriate along either of
the IPCC 1.5°C pathways that will keep the global averagetemperatures within that manageable range. We are now livingin the future that was overly discounted when the Framework
Convention on Climate Change was agreed in 1992. Avoiding
maladaptation means evading lock-ins and path dependence,and optimizing evolvability instead. Otherwise, in biologicalterms, we will find we are at a dead end.

UN ENVIRONMENT FRONTIERS 2018/19 REPORTJonah gas field, Wyoming, United States73MALADAPTATION TO CLIMATE CHANGE: AVOIDING PITFALLS ON THE EVOLVABILITY PATHWAY

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Sunset Crater Volcano National Monument near the Coconino National Forest
Photo credit: Coconino National Forest, U.S. Forest Service

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77

UN ENVIRONMENT FRONTIERS 2018/19 REPORTUNEP FRONTIERS
2016 REPORTEmerging Issues of Environmental Concern

2014
In 2016 UN Environment launched its new yearly publication
series, Frontiers - Emerging Issues of Environmental Concern. The
report identifies and provides an insight into a broad rangeof emerging environmental issues that require attention andaction from governments, stakeholders, decision makers aswell as the public at large. The first edition, Frontiers 2016,
presents the following six emerging issues.

78•

The Financial Sector: A Linchpin to Advance Sustainable
Development•

Zoonoses: Blurred Lines of Emergent Disease andEcosystem Health•

Microplastics: Trouble in the Food Chain•

Loss and Damage: Unavoidable Impacts of Climate Change
on Ecosystems•

Poisoned chalice: Toxin accumulation in crops in the era ofclimate change•

Exotic Consumerism: Illegal Trade in Live Animals

The Frontiers 2017 report presents the following emerging
issues.
• Antimicrobial Resistance: Investigating the Environmental
Dimension•

Nanomaterials: Applying the Precautionary
Principle•

Marine Protected Areas: At the Heart of Sustainable
Development•

Sand and Dust Storms: Subduing a Global
Phenomenon•

Solar Solutions: Bridging the Energy Gap for Off-Grid
Settlements•

Environmental Displacement: Human Mobility in the
AnthropocenePrinting: UNON, Publishing Services Section, Nairobi, ISO 14001:2004-certified

www
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unenvironment.org/frontiers

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