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Peatlands and carbon

Authors:
Assessment on
Peatlands,
Biodiversity
and Climate change
Main Report
Published By
Global Environment Centre, Kuala Lumpur
& Wetlands International, Wageningen
First Published in Electronic Format in December 2007
This version first published in May 2008
Copyright
© 2008 Global Environment Centre & Wetlands International
Reproduction of material from the publication for educational and
non-commercial purposes is authorized without prior permission
from Global Environment Centre or Wetlands International,
provided acknowledgement is provided.
Reference
Parish, F., Sirin, A., Charman, D., Joosten, H., Minayeva
, T.,
Silvius, M. and Stringer, L. (Eds.) 2008.
Assessment on
Peatlands, Biodiversity and Climate Change: Main Report
.
Global Environment Centre, Kuala Lumpur and
Wetlands
International, Wageningen.
Reviewer of Executive Summary
Dicky Clymo
Available from
Global Environment Centre
2nd Floor Wisma Hing,
78 Jalan SS2/72, 47300 Petaling Jaya,
Selangor, Malaysia.
Tel: +603 7957 2007,
Fax: +603 7957 7003.
Web: www.gecnet.info; www.peat-portal.net
Email: gecnet@genet.po.my
Wetlands International
PO Box 471
AL, Wageningen 6700
The Netherlands
Tel: +31 317 478861
Fax: +31 317 478850
Web: www.wetlands.org; www.peatlands.ru
ISBN
978-983-43751-0-2
Supported By
United Nations Environment Programme/Global Environment
Facility (UNEP/GEF) with assistance from the Asia Pacific
Network for Global Change Research (APN)
Design by
Regina Cheah and Andrey Sirin
Printed on Cyclus 100% Recycled Paper. Printing on recycled paper helps save
our natural resources and minimise environmental degradation.
Acknowledgements
The Assessment on P
eatlands, Biodiversity and Climate
Change was initiated by the project on Integrated
Management of Peatlands for Biodiversity and Climate
Change implemented by Wetlands International and the
Global Environment Centre with the support of UNEP-
GEF, the gover
(China, Indonesia and the Russian Federation) and
regions (ASEAN); as well as the Dutch and Canadian
governments and a range of other organisations including
the Asia-Pacific Network for Global Change Research
(APN).
Numerous experts on peatlands, biodiversity and climate
change have contributed to the development of the
assessment through contributing information and
references and reviewing drafts.
Contributors of photographs and illustrations including
Olivia Bragg, Dan Charman, Viktor Gusev,
Hans
Joosten, Richard Lindsay, Tatiana Minayeva, Faizal
Parish, Marcel Silvius, Andrey Sirin and Steve Zoltai are
thanked.
Contents
Foreword by the Secretariat of the CBD i.
Foreword by the United Nations Environment Program ii.
Foreword by GEC and Wetlands International iv.
Executive Summary v.
List of Authors xii.
Glossary xiv.
List of Figures xvi.
List of Tables xx.
Chapter 1: Introduction 1
1.1 Rationale for the Assessment 1
1.2 Purpose of the Assessment 4
1.3 Outline of the Assessment 6
1.4 Process of preparation of the Assessment 6
1.5 Scope and limitations 6
Chapter 2: What are peatlands? 8
Summary points 8
2.1 Definition 8
2.2 Peatland characteristics 9
2.3 Peat formation 10
2.4 Peatland distribution 11
2.5 Peatland ecology and peatland types 13
References 17
Chapter 3: Peatlands and people 20
Summary points 20
3.1 Human – peatland interactions 20
3.2 Benefits of peatlands 21
3.2.1 Regulation functions (ecosystem services) 22
3.2.2 Production functions 23
3.2.3 Carrier functions 26
3.2.4 Information functions 27
3.3 Peatlands and livelihoods 28
3.4 The root causes of human impacts on peatlands 30
3.5 Conflicts and wise use 33
References 37
Chapter 4: Peatlands and past climate change 39
Summary points 39
4.1 Climate and peatland characteristics 39
4.2 Past climate variability and peatland distribution 42
4.3 Peatland archives of past climate change 46
4.4 Peatland responses to past climate change 48
4.5 Peatland feedbacks to climate change 52
4.6 Recent changes in climate and peatland responses 53
References 56
Chapter 5: Peatlands and biodiversity 60
Summary points 60
Introduction 60
5.1 Peatland biodiversity: what makes peatlands different? 60
5.1.1 Peatlands and the biodiversity concept 62
5.1.2 Peatlands as habitats with specific features 63
5.1.3 Specific features of peatland biodiversity on the
species level 65
5.1.4 Specific features of peatland biodiversity on the
population level 66
5.1.5 Specific features of peatland biodiversity on the
ecosystem level 67
5.1.6 The specific role of peatlands in biodiversity maintenance 71
5.2 The taxonomic biodiversity of peatland 73
5.2.1 Microorganisms and lichens 73
5.2.2 Bryophytes and vascular plants 75
5.2.3 Invertebrates 77
5.2.4 Vertebrates 78
5.3 Human impacts on peatland biodiversity 80
References 91
Chapter 6: Peatlands and carbon 99
Summary points 99
6.1 Peatlands and carbon stock 99
6.2 Carbon accumulation in peatlands 104
6.3 Carbon losses from peatlands 105
6.4 Human impact on peatland carbon 107
References 111
Chapter 7: Peatlands and greenhouse gases 118
Summary points 118
7.1 GHG related to peatlands 118
7.2 Net peatland impact on GHG radiative forcing of the climate 119
7.3 Ecological and environmental control of GHG emission from peatlands 121
7.3.1 General 121
7.3.2 Carbon dioxide 123
7.3.3 Methane 124
7.3.4 Nitrogen oxide 126
7.4 GHG flux rate in natural peatlands 126
7.5 Human influence on GHG flux from peatlands 129
References 133
Chapter 8: Impacts of future climate change on peatlands 139
Summary points 139
8.1 Future climate change scenarios 139
8.2 Impacts of climate change on peatlands 143
8.2.1 Effects of increasing temperatures 143
8.2.2 Effects of precipitation changes 145
8.2.3 Hydrological changes 146
8.2.4 Changes in permafrost and snow cover 149
8.2.5 Sea level rise 150
8.2.6 Carbon dioxide fertilization 151
8.2.7 Other impacts of climate change on peatlands 151
References 152
Chapter 9: Management of peatlands for biodiversity and
climate change 155
Summary points 155
9.1 Protection and rehabilitation of peatlands 156
9.1.1 Protection of remaining peatlands 156
9.1.2 Fire prevention and control 157
9.1.3 Rehabilitation of degraded peatlands 158
9.2 Modification of peatland management strategies 161
9.2.1 Improved water management 161
9.2.2 Modification of agricultural practices 163
9.2.3 Modification of livestock management on peatlands 165
9.2.4 Modification of forestry practices 166
9.2.5 Modification of Peat extraction 168
9.3 Integrated management of peatlands 169
9.4 Peatlands in relation to policy processes 170
9.4.1 Peatlands and policy 170
9.4.2 Addressing root causes and enhancing implementation mechanisms 171
9.4.3 New emerging innovative options 172
9.4.4 The need for local policy embedding of innovative mechanisms 174
9.4.5 Harmful subsidies, policies and taxes 176
9.4.6 Synergy between conventions to develop integrated policy
frameworks 177
Conclusion 177
References 177
i
Foreword by the
Secretariat of the
Convention on Biological Diversity
The seventh meeting of the Conference of the Parties to the Convention on Biological Diversity
(CBD), held in Malaysia in 2004, welcomed the proposed Assessment on Peatlands, Biodiversity and
Climate Change. It is with great pleasure to see this significant undertaking present its final
conclusions.
The Assessment has demonstrated the importance of the biodiversity associated with these
ecosystems, the services they provide and their critical role in sustaining livelihoods, especially in
tropical areas. The role of peatlands in greenhouse gas regulation has also been clearly articulated.
We now need to raise the profile of these ecosystems in the debate on linkages between wetlands,
biodiversity and climate change for the conclusions drawn in this assessment demonstrate one of the
clearest opportunities for win-win outcomes. We have already moved in this direction. The twelfth
meeting of the Subsidiary Body on Scientific, Technical and Technological Advice, held in Paris in
July 2007, noted the importance of the outcomes of this assessment and requested that the Secretariat
of the CBD, in collaboration with the secretariats of relevant multilateral environment agreements and
other relevant partners, review opportunities for further action to support the conservation and
sustainable use of the biodiversity of tropical forested peatlands, as well as other wetlands, and to
report on progress to the ninth meeting of Conference of the Parties in Bonn in May 2008. These
concrete steps demonstrate that at Convention level we are serious about paying attention to the issues
identified. But the most important need is for this progress to be reflected in real changes to the
policies, management and use of peatlands on the ground.
The Assessment has helped put these important ecosystems on the map, addressed the important issues
and identified the responses that are needed. I would like to thank all of the people involved in
contributing to this assessment. I have every confidence that it will make a major difference to
improving the long-term sustainability of peatlands and therefore go down in history as a significant
contribution towards the achievement of the 2010 biodiversity target.
Ahmed Djoghlaf
Executive Secretary
Convention on Biological Diversity (CBD)
ii
Foreword by the
United Nations Environment
Programme
Climate change is emerging as the defining political, as well as environmental, concern of our era. But,
while emerging issues, such as avoided deforestation, are increasingly on the agenda, peatlands have
been largely left out of formal negotiations under such instruments as the UN Framework Convention
on Climate Change (UNFCCC) and its associated Kyoto Protocol, as well as the UN Convention on
Biological Diversity (CBD).
Tropical peat swamps, boreal forests and arctic permafrost regions, as well as temperate bogs, are a
true global heritage, occurring in more than 180 countries. Although they cover only 3 percent of the
land area, they store nearly 30 per cent of all global soil carbon. They hold approximately as much
carbon as is found in the atmosphere or as in the total of terrestrial biomass.
As such, peatlands currently present a significant unrealized opportunity for cost-effective measures in
mitigating and adapting to climate change. However, time is running out. The continued burning,
degradation, drainage and exploitation of peatlands all over the globe, and particularly in Southeast
Asia due to forest fires, constitute a ‘time bomb’ of massive amounts of below-ground stored carbon
ready to be released in the atmosphere. This will not only undo much of the mitigation effort already
achieved, but also go against the principles and goals of global greenhouse gas emission reduction.
As well as being the most important long-term carbon store in the terrestrial biosphere, peatlands have
broader significance. They provide water resources regulation and a wide range of other valuable
goods and services to industrial as well as agricultural societies. Peatland ecosystems are diverse and
unique, and often provide the last refuge for endangered species.
This timely Global Assessment of Peatlands, Biodiversity and Climate Change has been produced as
part of the UNEP/GEF Integrated Management of Peatlands for Biodiversity and Climate Change
project, led by Wetlands International and the Global Environment Centre, and funded by the Global
Environment Facility and various other donors. Both lead agencies and their partners have been
instrumental in putting peatlands and their wise use high on the agenda of the CBD Subsidiary Body
on Scientific, Technical and Technological Advice (SBSTTA) and of the Conferences of Parties (CoP)
to both the CBD and the UNFCCC, as well as the Ramsar Convention on Wetlands of International
Importance.
UNEP is glad that this publication’s policy recommendations have been adopted by the CBD SBSTTA
July 2007 Recommendation No XII/5 ‘Proposals for Integration of Climate Change Activities within
the Program of Work of the [CBD] Convention’, to advise the upcoming CBD CoP 9 , and request the
CBD Executive Secretary to convey its message to the UNFCCC CoP 13. This assessment helps to
strengthen the political agenda, both on peatlands and on Reduced Emissions from Deforestation and
Degradation (REDD). It provides options for the sustainable management of peatlands, and builds a
case for a cost effective contribution to averting further increases in carbon emissions worldwide, in
developing as well as developed countries.
It also complements previous UNEP-supported work, such as the GEF Soil Organic Carbon project,
developing measurement methodologies on carbon stock and fluxes, and the Assessments of Impacts
and Adaptations to Climate Change project (AIACC), developed with the UNEP/WMO
Intergovernmental Panel on Climate Change (IPCC) and funded by the GEF, to advance scientific
iii
understanding of climate change vulnerability and adaptation options in developing countries. The
Carbon Benefits Project (CBP) Modeling, Measurement, and Monitoring, a planned UNEP/World
Bank initiative, supported through the GEF, will further benefit peatland and REDD climate mitigation
programming by developing additional methodologies specifically to determine the carbon benefits of
GEF programme investments. UNEP looks forward to working even more intensively with global
partners in the future to incorporate peatlands and their dominant role in carbon emission mitigation
into international agreements and programmes.
Achim Steiner
United Nations Under-Secretary-General
Executive Director, UNEP
iv
Foreword by Global Environment Centre
and Wetlands International
Peatlands are one of the world’s most important ecosystems covering over 400 million ha and
representing about a third of the estimated area of the world’s wetlands. The global Assessment on
Peatlands, Biodiversity and Climate Change brings together vital information for the first time in one
volume. It includes analyses of information from numerous studies through out the world on different
aspects of peatland functions, values and management and their importance to both biodiversity
conservation and global climate regulation. The Assessment has revealed that peatlands are the most
important terrestrial ecosystem for carbon storage and hence for regulating climate. It has also
documented the key role that peatlands play in conservation of biodiversity at genetic, species and
ecosystem levels. It emphasizes that peatlands also play a critical role in water resource management
and provide critical resources and livelihood to millions of poor people around the world.
The Assessment has concluded that the current status and use of peatlands in most parts of the world is
not sustainable. Peatlands are degrading worldwide - releasing their stored carbon and losing their
value for biodiversity conservation and water resource management at an alarming rate. Millions of
people are now negatively affected in different regions by fires, floods and water shortages as a result
of peatland degradation. As the world’s climate changes the situation is predicted to worsen, as
increased temperatures and more frequent extreme events have further impacts on peatlands, further
reducing our adaptive capacity.
However, the Assessment also provides evidence that relatively simple changes in peatland
management can limit and even reverse negative impacts. Optimisation of water management in peat,
especially by reducing drainage is the most important measure to reduce greenhouse gas emissions
while reducing degradation and biodiversity loss. It makes a strong case that conservation and
rehabilitation of peatlands is a major, cost-effective tool to address climate change while providing co-
benefits for poverty reduction and biodiversity conservation.
Wetlands International and the Global Environment Centre – the two lead partners in the development
of this assessment are pleased to report these findings to the global community. We hope that this will
stimulate further debate and action both within the frameworks of the global environmental
conventions (including CBD, UNFCCC, UNCCD and the Ramsar Convention) as well as direct action
by all sectors at the country and local level in each region of the world. We commit to continue our
work together and with other partners to seek global action to conserve and sustainably use our
peatland resources.
Jane Madgwick Faizal Parish
Chief Executive Officer Director
Wetlands International Global Environment Centre
Assessment on Peatlands, Biodiversity and Climate Change
v
Executive Summary
This Executive Summary presents the key findings of the global Assessment on Peatlands,
Biodiversity and Climate Change. The Assessment was prepared through a review of scientific
information on the nature and value of peatlands in relation to biodiversity and climate change, the
impact of human activities and potential sustainable management options. It responds to decisions by
a range of global environmental conventions, including the Convention on Biological Diversity (CBD)
(programmes of work on inland water, forest and mountain biodiversity as well as the cross cutting
issue on biodiversity and climate change), the Ramsar Convention on Wetlands (Guidelines for global
action on peatlands). It is also a contribution to the UN Framework Convention on Climate Change
(UNFCCC) and the UN Convention to Combat Desertification (UNCCD). The Assessment has been
specifically welcomed by the Conference of Parties of the CBD.
The Assessment was prepared in the period 2005-2007 under the coordination of a multidisciplinary
international team of peatland, biodiversity and climate change specialists. Its preparation was
supported by UNEP-GEF and a range of other supporters.
Major overall findings
Peatlands are important natural ecosystems with high value for biodiversity conservation, climate
regulation and human welfare. Peatlands are those wetland ecosystems characterized by the
accumulation of organic matter (peat) derived from dead and decaying plant material under conditions
of permanent water saturation. They cover over 4 million km2 worldwide, occur in over 180 countries
and represent at least a third of the global wetland resource.
Inappropriate management is leading to large-scale degradation of peatlands with major environmental
and social impacts. Rehabilitation and integrated management of peatlands can generate multiple
benefits including decreasing poverty, combating land-degradation, maintaining biodiversity, and
mitigating climate change. Concerted action for the protection and wise use of peatlands should
therefore be a global priority linking work at global regional and local levels.
Some of the major overall findings of the assessment are:
Peatlands are the most efficient terrestrial ecosystems in storing carbon. While covering only 3% of
the World's land area, their peat contains as much carbon as all terrestrial biomass, twice as much as
all global forest biomass, and about the same as in the atmosphere.
Peatlands are the most important long-term carbon store in the terrestrial biosphere. They sequester
and store atmospheric carbon for thousands of years.
Peatlands are critical for biodiversity conservation and support many specialised species and unique
ecosystem types, and can provide a refuge for species that are expelled from non-peatland areas
affected by degradation and climate change.
Peatlands play a key role in water resource management storing a significant proportion of global
freshwater resources. Peatland degradation can disrupt water supply and flood control benefits.
Degradation of peatlands is a major and growing source of anthropogenic greenhouse gas emissions.
Carbon dioxide emissions from peatland drainage, fires and exploitation are estimated to currently
be equivalent to at least 3,000 million tonnes per annum or equivalent to more than 10% of the
global fossil fuel emissions.
Peatland degradation affects millions of people around the world. Drainage and fires in SE Asian
peat swamp forests jeopardise the health and livelihood of millions of people in several countries in
Executive Summary
vi
the region. The destruction of mountain peatlands in Africa, Asia and Latin America threatens the
water and food supply for large rural and urban populations.
Climate change impacts are already visible through the melting of permafrost peatlands and
desertification of steppe peatlands. In the future, impacts of climate change on peatlands are
predicted to significantly increase. Coastal, tropical and mountain peatlands are all expected to be
particularly vulnerable.
Conservation, restoration and wise use of peatlands are essential and very cost-effective measures
for long term climate change mitigation and adaptation as well as biodiversity conservation.
Optimising water management in peatlands (i.e. reducing drainage) is the single highest priority to
combat CO2 emissions from oxidation and fires as well as address peatland degradation and
biodiversity conservation.
There is an urgent need to strengthen awareness, understanding and capacity to manage peatlands in
most countries – to address peatland degradation, biodiversity conservation and climate change.
Key characteristics of peatlands
Peatlands are wetland ecosystems that are characterized by the accumulation of organic matter (peat),
which is derived from dead and decaying plant material under conditions of permanent water
saturation. There are many different types of peatland, depending on geographic region, terrain and
vegetation type. A major distinction is between bogs (which are fed only by precipitation and are
nutrient-poor) and fens (which are fed by surface or ground water as well as precipitation and tend to
be more nutrient rich). Peatlands may be naturally forested or naturally open and vegetated with
mosses, sedges or shrubs. Peat formation is strongly influenced by climatic conditions and topography.
In northern latitudes or high altitudes the temperature may be high enough for plant growth but too
low for vigorous microbial activity. Significant areas of peatlands are found in tropical and sub-
tropical latitudes where high plant productivity combines with slow decomposition as a result of high
rainfall and humidity. In some cases peatlands were formed during wetter climatic periods thousands
of years ago but, in the drier prevailing climate, no longer accumulate peat.
The major characteristics of natural peatlands are permanent water logging, development of specific
vegetation, the consequent formation and storage of peat and the continuous (upward) growth of the
surface.
Peatland distribution and peat formation and storage are primarily a function of climate, which
determines water conditions, vegetation productivity and the decomposition rate of dead organic
material.
Peatlands are found in almost every country, but occur primarily in the boreal, subarctic and tropical
zones as well as appropriate zones in mountains. More detailed assessment of their extent, nature
and status is needed. Many peatlands are not recognised as such but are classified as marshes,
meadows, or forests.
As a result of different climatic and biogeographic conditions, a large diversity of peatland types
exists. However because of similar ecohydrological processes, they share many ecological features
and functions.
In northern regions and highlands, peatlands and permafrost are mutually dependent.
The complex relationship between plants, water, and peat makes peatlands vulnerable to a wide
range of human interference.
Peatlands and people
Peatlands and people are connected by a long history of cultural development. Humans have directly
utilised peatlands for thousands of years, leading to differing and varying degrees of impact.
Assessment on Peatlands, Biodiversity and Climate Change
vii
For centuries, some peatlands worldwide have been used in agriculture, both for grazing and for
growing crops. Large areas of tropical peatlands have in recent years been cleared and drained for
food crops and cash crops such as oil palm and other plantations. Many peatlands are exploited for
timber or drained for plantation forestry. Peat is being extracted for industrial and domestic fuel, as
well as for use in horticulture and gardening. Peatlands also play a key role in water storage and
supply and flood control.
Many indigenous cultures and local communities are dependent on the continued existence of
peatlands, but peatlands also provide a wealth of valuable goods and services to industrial societies
such as livelihood support, carbon storage, water regulation and biodiversity conservation.
The many values of peatlands are generally poorly recognised and this is one of the root causes of
degradation or avoidable conflicts about uses.
The main human activities that impact peatlands include drainage for agriculture and forestry, land
clearing and burning, grazing, peat extraction, infrastructure and urban development, reservoir
construction, and pollution.
Deterioration of peatlands has resulted in significant economic losses and social impacts, and has
created tensions between key stakeholders at local, regional and international levels.
Peatlands are often the last expanses of undeveloped land not in private ownership, so they are
increasingly targeted by development that needs large areas of land, such as airports, plantations,
windfarms and reservoirs.
Peatlands and past climate change
The form and function of peatlands and the distribution of peatland species depend strongly on the
climate. Therefore climate exerts an important control on ecosystem biodiversity in peatlands.
Climate change is a normal condition for the Earth and the past record suggests continuous change
rather than stability. The last 2 million years of Earth history (the Quaternary period) are characterised
by a series of cold glacial events with warmer intervening interglacial periods. Peatlands expanded and
contracted with changes in climate and sea-level. Many current peatlands started growth following the
warming after the last glacial maximum. The initiation of new peatlands has continued throughout the
postglacial period in response to changes in climate and successional change.
Climate is the most important determinant of the distribution and character of peatlands. It
determines the location and biodiversity of peatlands throughout the world.
The earth has experienced many climate changes in the past, and peatland distribution has varied in
concert with these changes. Most peatlands began growth during the current postglacial period.
Peatland extent has increased over the course of the last 15,000 years.
In the constantly accumulating peat, peatlands preserve a unique record of their own development as
well as of past changes in regional vegetation and climate .
Records show that the vegetation, growth rate (carbon accumulation) and hydrology of peatlands
were altered by past climate change. This information helps in making predictions of future impacts
of climate change.
Peatlands affect climate via a series of feedback mechanisms including: sequestration of carbon
dioxide, emission of methane, change in albedo and alteration of the micro- and mesoclimate
Natural peatlands were often resilient to climate changes in the past. However, the rate and
magnitude of predicted future climate changes and extreme events (drought, fires, flooding, erosion)
may push many peatlands over their threshold for adaptation.
Some expected impacts of recent climate change are already apparent in the melting of permafrost
peatlands, changing vegetation patterns in temperate peatlands, desertification of steppe peatlands,
and increased susceptibility to fire of tropical peatlands.
Human activities such as vegetation clearance, drainage and grazing have increased the vulnerability
of peatlands to climate change.
Executive Summary
viii
Peatlands and biodiversity
Peatlands are unique, complex ecosystems of global importance for biodiversity conservation at
genetic, species and ecosystem levels. They contain many species found only or mainly in peatlands.
These species are adapted to the special acidic, nutrient poor and water-logged conditions of peatlands.
They are vulnerable to changes resulting from direct human intervention, changes in their water
catchment and climate change, that may lead to loss of habitats, species and associated ecosystem
services. The biodiversity values of peatlands demand special consideration in conservation strategies
and land use planning.
Peatlands play a special role in maintaining biodiversity at the species and genetic level as a result of
habitat isolation and at the ecosystem level as a result of their ability to self-organise and adapt to
different physical conditions.
Although species diversity in peatlands may be lower, they have a higher proportion of characteristic
species than dryland ecosystems in the same biogeographic zone.
Peatlands may develop sophisticated self-regulation mechanisms over time, resulting in high within-
habitat diversity expressed as conspicuous surface patterns.
Peatlands are important for biodiversity far beyond their borders by maintaining hydrological and
micro-climate features of adjacent areas and providing temporary habitats or refuge areas for
dryland species.
Peatlands are often the last remaining natural areas in degraded landscapes and thus mitigate
landscape fragmentation. They also support adaptation by providing habitats for endangered species
and those displaced by climate change.
Peatlands are vulnerable to human activities both within the peatland habitats themselves and in
their catchments. Impacts include habitat loss, species extinction and loss of associated ecosystem
services.
The importance of peatlands for maintaining global biodiversity is usually underestimated, both in
local nature conservation planning and practices, as well as in international convention deliberations
and decisions.
Peatlands and carbon
Peatlands are some of the most important carbon stores in the world. They contain nearly 30 percent of
all carbon on the land, while only covering 3 percent of the land area. Peatland ecosystems contain
disproportionately more organic carbon than other terrestrial ecosystems.
Peatlands are the top long-term carbon store in the terrestrial biosphere and - next to oceanic deposits
– Earth's second most important store. Peatlands have accumulated and stored this carbon over
thousands of years, and since the last ice age peatlands have played an important role in global
greenhouse gas balances by sequestering an enormous amount of atmospheric CO2.
Peatlands in many regions are still actively sequestering carbon. However the delicate balance
between production and decay easily causes peatlands to become carbon sources following human
interventions. Anthropogenic disturbances (especially drainage and fires) have led to massive carbon
losses from peatland stores and generated a significant contribution to global anthropogenic CO2
emissions. Peatland restoration is an effective way to maintain the carbon storage of peatlands and to
re-initiate carbon sequestration.
While covering only 3% of the World's land area, peatlands contain at least 550 Gt of carbon in their
peat. This is equivalent to 30% of all global soil carbon, 75% of all atmospheric C, equal to all
Assessment on Peatlands, Biodiversity and Climate Change
ix
terrestrial biomass, and twice the carbon stock in the forest biomass of the world. This makes
peatlands the top long-term carbon store in the terrestrial biosphere.
Peatlands are the most efficient carbon (C) store of all terrestrial ecosystems. Peatlands contain more
carbon per ha than other ecosystems on mineral soil: in the (sub)polar zone, 3.5 times, in the boreal
zone 7 times, in the tropical zone 10 times as much.
Peatlands store carbon in different parts of their ecosystem (biomass, litter, peat layer, mineral
subsoil layer), each with their own dynamics and turn-over.
The peat layer is a long-term store of carbon. Peatlands have accumulated and stored this carbon
over thousands of years. Permanent waterlogging and consequent restricted aerobic decay is the
main prerequisite for continued long-term storage of carbon in peatlands.
Most coal and lignite and part of the 'mineral' oil and natural gas originated from peat deposits in
previous geological periods.
Peat growth depends on a delicate balance between production and decay. Natural peatlands may
shift between carbon sink and source on a seasonal and between-year time scale, but the
accumulation of peat demonstrates that their long-term natural balance is positive.
Human interventions can easily disturb the natural balance of production and decay turning
peatlands into carbon emitters. Drainage for agriculture, forestry and other purposes increases
aerobic decay and changes peatlands from a sink of carbon to a source. Peat extraction (for fuel,
horticulture, fertilizers, etc.) transfers carbon to the atmosphere even more quickly.
Peatland drainage also facilitates peat fires, which are one of the largest sources of carbon released
to the atmosphere associated with land management.
Fluxes of dissolved (DOC) and particulate (POC) organic carbon constitute important carbon losses
from peatlands that may substantially increase as a result of human impact and climate change
Carbon dioxide emissions from peatland drainage, fires and exploitation are estimated to currently
be at least 3000 million tonnes a year equivalent to more than 10% of the global fossil fuel
emissions.
Peatland conservation and restoration are effective ways to maintain the peatland carbon store and to
maximise carbon sequestration with additional benefits for biodiversity, environment and people.
Peatlands and greenhouse gases
The world's peatlands influence the global balance of three main greenhouse gases (GHG) carbon
dioxide, methane and nitrous oxide (CO2, CH4, and N2O). In their natural state, peatlands remove CO2
from the atmosphere via peat accumulation and they emit methane. The long-term negative effect of
methane emissions is lower than the positive effect of CO2 sequestration. By sequestering and storing
an enormous amount of atmospheric CO2 peatlands have had an increasing cooling effect, in the same
way as in former geological eras, when they formed coal, lignite and other fossil fuels.
When peatlands are disturbed, they can become significant sources of carbon dioxide and at the same
time do not totally stop emitting methane which is still intensively released from drainage ditches and
under warm wet conditions even from milled peat surfaces and peat stockpiles. Drained peatlands,
especially after fertilization, can become an important source of nitrous oxide. Peatland restoration
reduces net GHG emissions to the atmosphere, certainly in the long-term.
Natural peatlands affect atmospheric burdens of CO2, CH4 and N2O in different ways and so play a
complex role with respect to climate.
Since the last ice age peatlands have sequestered enormous amounts of atmospheric CO2.
GHG fluxes in peatlands have a spatial (zonal, ecosystem, site and intersite) and temporal
(interannual, seasonal, diurnal) variability, which needs to be considered in assessment and
management.
Small changes in the ecology and hydrology of peatlands can lead to big changes in GHG fluxes
through influence on peatland biogeochemistry.
Executive Summary
x
In assessing the role of peatlands in global warming, the different time frame and radiative forcing
of continuous CH4 emission and CO2 sequestration should be carefully evaluated rather than using
simple global warming potential calculations.
Anthropogenic disturbances (especially drainage and fires) have led to massive increases in net
emissions of GHG from peatlands, which are now a significant contribution to global anthropogenic
emissions.
Peatland drainage leads to increased CO2 emissions in general and a rise of N2O release in nutrient
rich peatlands. It may not always significantly reduce CH4 emissions.
Because of the large emissions from degraded peatlands, rewetting and restoring them is one of the
most cost-effective ways of avoiding anthropogenic greenhouse gas emissions.
Impacts of future climate change on peatlands
The strong relationship between climate and peatland distribution suggests that future climate change
will exert a strong influence on peatlands. Predicted future changes in climate of particular relevance
to peatlands include rising temperatures, changes in the amount, intensity and seasonal distribution of
rainfall, and reduced snow extent in high latitudes and in mountain areas. These changes will have
significant impacts on the peatland carbon store, greenhouse gas fluxes and biodiversity.
Global temperature rises of 1.1-6.4°C will be higher in northern high latitudes where the greatest
extent of peatlands occurs.
High latitudes are likely to experience increased precipitation while mid latitudes and some other
regions may have reduced precipitation at certain times of the year. All areas may be susceptible to
drought due to increased variability in rainfall.
Increasing temperatures will increase peatland primary productivity by lengthened growing seasons.
Decay rates of peat will increase as a result of rising temperatures, potentially leading to increased
CH4 and CO2 release. Changes in rainfall and water balance will affect peat accumulation and decay
rates.
Tree lines in northern peatlands will shift poleward as a result of higher summer temperatures, and
hydrological changes may result in increased forest extent on open peatlands. The resulting reduced
albedo will positively feed back on global warming.
Increased rainfall intensity may increase peatland erosion. This may be amplified by anthropogenic
drainage and overgrazing.
Greater drought will lead to an increase of fire frequency and intensity, although human activity is
expected to remain the primary cause of fire.
Hydrological changes, combined with temperature rise, will have far-reaching effects on greenhouse
gas exchange in peatlands. Drier surfaces will emit less CH4, more N2O and more CO2, and the
converse for wetter surfaces.
Melting permafrost will probably increase CH4 emissions and lead to increased loss of dissolved
organic carbon in river runoff.
Inundation of coastal peatlands may result in losses of biodiversity and habitats, as well as in
increased erosion, but local impacts will depend on rates of surface uplift.
The combined effect of changes in climate and resultant local changes in hydrology will have
consequences for the distribution and ecology of plants and animals that inhabit peatlands or use
peatlands in a significant part of their life cycles.
Human activities will increase peatland vulnerability to climate change in many areas. In particular,
drainage, burning and over-grazing will increase the loss of carbon from oxidation, fire and erosion.
Assessment on Peatlands, Biodiversity and Climate Change
xi
Management of peatlands for biodiversity and climate change
The sustainable management of peatlands requires the integration of approaches for biodiversity,
climate change and land degradation and close coordination between different stakeholders and
economic sectors.
The Assessment has found that:
The current management of peatlands is generally not sustainable and has major negative impacts on
biodiversity and climate.
Strict protection of intact peatlands is critical for the conservation of biodiversity and will maintain
their carbon storage and sequestration capacity and associated ecosystem functions.
Changes in peatland management (such as better water and fire control in drained peatlands) can
reduce land degradation and can limit negative impact on biodiversity and climate.
Optimising water management in peatlands (i.e. reducing drainage) is the single highest priority to
combat carbon dioxide emissions from peat oxidation and fires as well as address peatland
degradation and biodiversity conservation.
Restoration of peatlands can be a cost-effective way to generate immediate benefits for biodiversity
and climate change by reducing peatland subsidence, oxidation and fires.
New production techniques such as wet agriculture ('paludiculture') should be developed and
promoted to generate production benefits from peatlands without diminishing their environmental
functions.
A wise use approach is needed to integrate protection and sustainable use and to protect peatland
ecosystem services from increasing pressure from people and changing climate.
Peatland management should be integrated into land use and socio-economic development planning
by a multi-stakeholder, ecosystem, river basin and landscape approach.
Enhancing awareness and capacity, addressing poverty and inequity, and removing perverse
incentives are important to tackle the root causes of peatland degradation.
Local communities have a very important role as stewards of peatland resources and should be
effectively involved in activities to restore and sustain the use of peatland resources.
The emerging carbon market provides new opportunities for peat swamp forest conservation and
restoration and can generate income for local communities.
Plans for integrated peatland management should be developed at local, national and regional levels
as appropriate.
xii
List of Authors
Lead authors
Dan J. Charman. School of Geography, University of Plymouth, Plymouth, Devon, PL4 8AA, United
Kingdom; E-mail: dcharman@plymouth.ac.uk
Hans Joosten. Greifswald University, Institute of Botany and Landscape Ecology, Grimmer Strasse
88, D-17487 Greifswald, Germany; E-mail: joosten@uni-greifswald.de / International Mire
Conservation Group
Jukka Laine. Finnish Forest Research Institute, Parkano Research Unit, Kaironiementie 54, 39700
Parkano, Finland; E-mail: Jukka.Laine@metla.fi
David Lee. Global Environment Centre, 2nd Floor, Wisma Hing, 78, Jalan SS2/72, 47300 Petaling
Jaya, Selangor, Malaysia; E-mail: david@genet.po.my / National Capacity Needs Self Assessment
Global Environment Management (UNDP/GEF) Ministry of Natural Resources & Environment
Conservation & Environment Management Division Level 2, Podium 2, Lot 4G3, Precinct 4 Federal
Government Administrative Centre 62574 Putrajaya, Malaysia; E-mail: david@genet.po.my
Tatiana Minayeva. Federal Centre of Geoecological Systems, Ministry of Natural Resources of
Russian Federation / Wetlands International Russia Programme. Kedrova 8-1, Moscow, 117292,
Russian Federation; Email: tminaeva@ecoinfo.ru
Sofieke Opdam. Wageningen University. Wageningen, The Netherlands.
Faizal Parish. Global Environment Centre, 2nd Floor, Wisma Hing, 78, Jalan SS2/72, 47300 Petaling
Jaya,Selangor, Malaysia; E-mail: fparish@genet.po.my
Marcel Silvius. Wetlands International Headquarters. Droevendaalsesteeg 3A 6708 PB Wageningen,
Wageningen, The Netherlands; E-mail: marcel.silvius@wetlands.org
Andrey Sirin. Laboratory of Peatland Forestry and Amelioration, Institute of Forest Science, Russian
Academy of Sciences, Uspenskoye, Moscow Region 143030, Russian Federation; E-mail:
sirin@proc.ru
xiii
Contributing Authors
Robert K. Booth. Earth & Environmental Science Department, Lehigh University, 31 Williams Drive,
Bethlehem, PA 18015 USA; E-mail: robert.booth@lehigh.edu
Olivia Bragg. School of Social Sciences (Geography), University of Dundee, DD1 4HN, United
Kingdom; E-mail: o.m.bragg@dundee.ac.uk
Chen Ke Lin. Wetlands International China. Room 501, Grand Forest Hotel No. 3A, Beisanhuan
Zhonglu Road Beijing 100029, P.R.People's Republic of China; E-mail: ckl@wetwonder.org
Oksana Cherednichenko. Geobotany Department, Lomonosov Moscow State University, Leninskije
Gory 1 bd 12, Moscow, 119899, Russian Federation; E-mail: sciapoda@mail.ru
John Couwenberg. University of Greifswald, Institute of Botany and Landscape Ecology, Grimmer
Strasse 88; 17487 Greifswald, Germany; E-mail: couw@gmx.net
Wim Giesen. Euroconsult NV, Amsterdamseweg 15, 6814 CM Arnhem, The Netherlands; E-mail:
wimgiesen@hotmail.com
Ab Grootjans. Community and Conservation Ecology Group, University of Groningen, P.O.Box 14,
9750 AA Haren, The Netherlands; E-mail: A.P.Grootjans@rug.nl
Piet-Louis Grundling. Department of Geography, University of Waterloo, Canada / IMCG-Africa, PO
Box 912924, Silverton, 0127, SOUTH AFRICA; e-mail: peatland@mweb.co.za
Markku Mäkilä. Geological Survey of Finland, Southern Finland Office, P.O.BOX 96, FIN-02151
Espoo, Finland; E-mail: markku.makila@gtk.fi
Valery Nikolaev. National Park “Valdayski”, Pobedy Street, 5, Valday, Novgorod Region, 175400
Russian Federation; E-mail: valdpark@novgorod.net
Mark Reed. Sustainability Research Institute School of Earth and Environment University of Leeds
West Yorkshire LS2 9JT, United Kingdom; E-mail: mreed@env.leeds.ac.uk
Lindsay Stringer. Sustainability Research Institute, School of Earth and Environment, University of
Leeds, LS2 9JT, United Kingdom; E-mail: l.stringer@see.leeds.ac.uk
Nyoman Suryadiputra. Wetlands International, Indonesia. Jl. A. Yani, No. 53 Bogor 16161 Indonesia;
E-mail: nyoman@wetlands.or.id
Sake van der Schaaf. Wageningen University, Soil Physics, Ecohydrology and Groundwater
Management, Environmental Sciences Group, POB 47, 6700AA Wageningen, The Netherlands; E-
mail: Sake.vanderschaaf@wur.nl
Gert-Jan van Duinen. Bargerveen Foundation/Departments of Environmental Science and Animal
Ecology & Ecophysiology, Radboud University Nijmegen, P.O. Box 9010, NL-6500 GL Nijmegen, The
Netherlands; E-mail: g.vanduinen@science.ru.nl
xiv
Glossary
Aapa mire: A mire complex with minerotrophic
peat layer and pronounced surface pattern of wet
flarks and hummocky mostly oligotrophic
dwarf-shrub strings.
Acrotelm: Upper peat producing layer of mire
with a distinct hydraulic conductivity gradient in
which water level fluctuations and most of
horizontal water flow occur.
Blanket bog: Bog in a very humid climate,
which forms a blanket-like layer over the
underlying mineral soil.
Bog (raised bog): Mire raised above the
surrounding landscape and only fed by
precipitation.
Catotelm: The lower permanently water
saturated layer in a peatland, with relatively low
hydraulic conductivity and rate of decay.
Cut-away peatland: What remains of a peatland
after all the peat which can be economically
removed has been extracted.
Fen: Peatland receiving inflow of water and
nutrients from the mineral soil. Distinguished
from swamp forest by a lack of tree cover or with
only a sparse crown cover. Indistinctly separated
from marsh (which is always beside open water
and usually has a mineral substrate). See also
minerotrophic peatland.
Flark: Elongated wet depressions with sparse
vegetation (mud-bottom) in string mires; most of
the time waterlogged or even flooded. Also called
rimpi (Finnish).
Flood mires: Mires in which periodical flooding
by an adjacent open water body (sea, lake, river)
enables peat accumulation.
Fluvial mires: Mires associated with rivers.
Geogenous peatland: Peatland subject to
external flows.
Hummock: Peatland vegetation raised 20-50 cm
above the lowest surface level, characterized by
drier-occurring mosses, lichens, and dwarf shrubs.
Infilling, terrestrialization: The process
whereby peat develops on the margins and into
the centers of ponds, lakes, or slow-flowing rivers.
Lagg: A narrow fen or swamp surrounding a
bog, receiving water both from the bog and from
the surrounding mineral soil.
Limnogenous peatland: Geogeneous peatland
that develops on the ground along a slow-flowing
stream or a lake.
Marsh: Develops mostly on mineral soil, but
could be a peatland. Beside open water, with
standing or flowing water, or flooded seasonally.
Submerged, floating, emergent, or tussocky
vegetation.
Mesotrophic peatland: Intermediate peatland
between minerotrophic and ombrotrophic.
Minerotrophic peatland: Peatland receiving
nutrients through an inflow of water that has
filtered through mineral soil.
Mire: Synonymous with any peat-accumulating
wetland. A peatland where peat is currently
forming and accumulating.
Mire complex: An area consisting of several
hydrologically connected, but often very different,
mire types; sometimes separated by mineral soil
uplands.
Mixed mire: A mire type with bog and fen
features or sites in close connection.
Moor: Synonymous of mire (Europe).
Muskeg: Large expanse of peatlands or bogs
(Canada and Alaska).
Oligotrophic peatland: Peatland with poor to
extremely poor nutrient levels.
Ombrogenous peatland: Peatland receiving
water and nutrients only from atmosphere. Also
called ombrotrophic. See Bog.
Palsa mire: Peatland complex of the
discontinuous permafrost region, with palsas
(peat mounds or plateaus usually ombrotrophic)
swelling out above the adjacent unfrozen
peatland (usually fen).
xv
Paludification: The formation of marsh or
waterlogged conditions: also refers to peat
accumulation which starts directly over a
formerly dry mineral soil.
Peat: Fibric organic sedentarily accumulated
material with virtually all of the organic matter
allowing the identification of plant forms;
consists of at least 30% (dry weight) of dead
organic material.
Peat extraction: The excavation and drying of
wet peat and the collection, transport and storage
of the dried product.
Peatland: An area with or without vegetation
with a naturally accumulated peat layer at the
surface of at least 30 cm depth.
Polygon mire: Permafrost peatland patterned
complex which consists of closed, roughly
equidimensional polygons bounded by cracks,
with high or low centers, and often with ridges
along the margins.
Primary peat format ion: The process
whereby peat is formed directly on freshly
exposed, wet mineral soil.
Pristine mire: Mire which has not been
disturbed by human activity in a way which
damages its ecosystem.
Quaking bog (quagmire, quaking mat, floating
mat, Schwingmoor): Mire in which the peat
layer and plant cover is only partially attached to
the basin bottom or is floating like a raft.
Raised bog: Deep peat deposits that fill entire
basins, develop a dome raised above ground
water level, and receive their inputs of nutrients
from precipitation.
Riparian peatland: Peatland adjacent to a river
or stream, and, at least periodically, influenced
by flooding.
Sloping mire: Mire with a sloping surface.
Soligenous peatland: Geogenous peatland that
develops with regional interflow and surface
runoff.
Spring mire: Mire that is mainly fed by spring
water.
String: Elongated ridges in patterned fens and
bogs arranged perpendicularly to the slope with
hummock or lawn level vegetation.
Swamp: Usually forested minerotrophic peatland.
Separate from wooded fens due to a denser tree
canopy. Also peat swamp forest.
Terrestrialisation: The accumulation of
sediments and peats in open water. See infilling.
Topogenous peatland: Geogenous peatland with
a virtually horizontal water table, located in
basins.
Wetland: Land with the water table near the
surface. Inundation lasts for such a large part of
the year that the dominant organisms must be
adapted to wet and reducing conditions. Usually
includes shallow water, shore, marsh, swamp,
fen, and bog.
Wetland (Ramsar definition): Areas of marsh,
fen, peatland or water, whether natural or
artificial, permanent or temporary, with water
that is static, flowing, fresh, brackish or salt,
including areas of marine water, the depth of
which at low tide does not exceed six meters.
References
Joosten, H. and Clarke, D. 2002. Wise use of mires and
peatlands Background and principles including a
framework for decision-making. International Mire
Conservation Group / International Peat Society.
Mitsch W.J. and Gosselink J.G. 2000. Wetlands. Third Edition.
John Wiley and Sons.
Rydin, H. and Jeglum, J. K. 2006. The biology of peatlands.
Oxford University Press.
The Ramsar Convention on Wetlands http://www.ramsar.org/
xvi
List of Figures
Figure 1.1
Distribution of mires/peatlands in the world.
Figure 2.1
The relation between “peatland”, “wetland”, and “mire”.
Figure 2.2
Altitude for latitude: in mountains the climate across vast latitudinal
distances is represented over short elevational distances.
Figure 2.3
Percentage of the area covered with peatland per country.
Figure 2.4
The interrelations between plants, water and peat in a mire.
Figure 2.5
Important services of mires and peatlands.
Figure 2.6
The classical difference between “bog” and “fen” peatlands.
Figure 2.7
Ecological mire types for Central Europe with their characteristic ranges
of soil pH (measured in KCl) and N/C ratio (Kjeldahl nitrogen
determination).
Figure 2.8
The difference between terrestrialization and paludification.
Figure 2.9
Bogs change their surface patterns but not their overall functioning as a
consequence of climate change.
Figure 3.1
The contribution of different human activities to peatland losses.
Figure 4.1
Climatically suitable areas for blanket mire formation.
Figure 4.2
Relationships between temperature, precipitation and abundance of three
species of Sphagnum in peatlands in western Canada.
Figure 4.3
Global temperature change for the last 65 million years, as shown by
oxygen isotopes in benthic foraminifera in ocean sediments, for the last
450,000 years, as shown by oxygen isotope variations in ice cores, and
since AD 1850 from instrumental meteorological records.
1
8
11
12
15
15
16
16
17
17
31
40
41
43
xvii
Figure 4.4
Changes in peatland surface wetness over the past 4500 years inferred
from 12 records of reconstructed water table variability from northern
Britain.
Figure 4.5
Periods of intensive peat accumulation in different regions of Eurasia.
Figure 4.6
Average rate of carbon accumulation in the three raised bogs in southern
Finland, lake-level fluctuations in Finland and in Sweden, and the
quantitative annual mean temperature reconstruction based on pollen.
Figure 4.7
The spread of peatlands in the northern high latitudes as indicated by
dates on basal peat, compared to estimates of northern hemisphere
methane emissions based on the interpolar CH4 gradient, atmospheric
methane concentration from the GISP2 (Greenland) and the Dome C
(Antarctica) ice cores, and the atmospheric CO2 concentration (Dome C
ice core).
Figure 5.1
A classical example of phenetic diversity in peatlands are the ecological
forms of Scotch Pine (Pinus sylvestris L.).
Figure 5.2
Dominance-diversity curves for forested peatland and natural forest types
on mineral soil along a gradient of humidity and fertility in Central
European Russia.
Figure 5.3
The Whittaker (1972) spatial concept of biodiversity.
Figure 5.4
The elements of hierarchical mire classification.
Figure 5.5
Spatial heterogeneity and ecosystem biodiversity are typical
characteristics of peatlands.
Figure 5.6
Only two Ramsar wetland categories acknowledge peatlands, and at least
five more Ramsar categories may include peatlands.
Figure 5.7
With increasing distance to peatlands fewer amphibians can reach shelter
and species diversity decreases.
Figure 5.8
The contribution of different ecological groups to the total vascular plant
species richness in a region depends on biogeographical factors and
climate.
Figure 5.9
Peatland species and species originally typical for other habitats found in
peatlands of Mongolia.
49
50
51
53
61
62
63
68
69
70
72
76
77
xviii
Figure 5.10
Invertebrates use habitat diversity effectively in time and space and
similar species can occur together using very small but constant niches.
Figure 5.11
Amphibian habitat preferences in Belarus and globally.
Figure 5.12
Endangered butterflies endemic for peatlands.
Figure 6.1
Land Area, Carbon density, and Total Carbon Pool of the major terrestrial
biomes.
Figure 6.2
The development of coal from peat.
Figure 6.3
Remaining part of net primary production in time.
Figure 6.4
Long-term apparent rate of Carbon accumulation LORCA peat
accumulation rates from Finland.
Figure 6.5
Components of the peat carbon cycle.
Figure 6.6
Peatland CO2 emissions as a function of drainage depths and climate
Figure 6.7
Dynamics of the carbon stores of an oligotrophic tall sedge pine fen site
during the first 300 years after drainage.
Figure 7.1
The hierarchical relations of processes proposed to affect methane
emissions and the spatial and temporal scales at which these processes
predominate.
Figure 7.2
Simplified description of carbon flow and peat formation in a peatland
with an oxic upper part and an anoxic layer beneath.
Figure 7.3
A generalized depth profile describing distribution of the methanogenic and
methanotrophic communities in relation to the mean water table in a peatland.
Figure 7.4
Simplified scheme of the nitrogen cycle in peatlands.
Figure 7.5
GHG flux measurements.
78
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82
100
103
104
105
106
108
110
122
124
125
125
128
xix
Figure 7.6
Schematic presentation of the GHG balances of undrained and drained
peatland sites.
Figure 7.7
Peatlands disturbed by human activities often become sources of CO2 but
do not totally stop emitting CH4 which is released especially from
drainage ditches.
Figure 7.8
The emission values from cultivated peatlands show large ranges of
uncertainty.
Figure 8.1
Projected changes in temperature in 2020-2029 and 2090-2099 compared
to the period 1980-1999, based on the multimodel ensemble for the IPCC
A2 emissions scenario.
Figure 8.2
Key future changes in mean and extremes of precipitation, snow and
drought.
Figure 8.3
Changes in European growing season length and an index of drought
stress for boreal, temperate and Mediterranean regions.
Figure 8.4
Factors affecting the sensitivity of organic matter to decay.
Figure 9.1
Tentative estimates of CO2 emissions from peatland fires in Indonesia
1997 – 2006.
Figure 9.2
Erosion feature resulting from an historic accidental fire and an eroded
area resulting from the same fire that has been reseeded and treated with
heather brash on Bleaklow, Peak District National Park, UK.
Figure 9.3
Managed burning on UK peatlands for grouse and sheep management
showing a fire being lit, burning, being put out and after the fire.
Figure 9.4
Peatland restoration. Blocking of a canal in degraded peat swamp forests
in Central Kalimantan, by local communities using manual traditional
techniques.
Figure 9.5
Change in area of remaining natural wetlands (Marshes) in Sanjiang plain,
Heilonjiang Province, China 1954-2005.
Figure 9.6
Jelutung (Dyera sp.), an indigenous latex producing peat swamp forest
species is being planted along the banks of blocked drainage channels in
abandoned agricultural land in Central Kalimantan, Indonesia.
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xx
List of Tables
Table 1.1
Peatland Uses and Functions.
Table 2.1
Characteristic peat forming plants in different parts of the Earth.
Table 2.2
Distribution of peatlands (> 30 cm of peat) over the continents.
Table 2.3
Ecological mire types and their pH characterization.
Table 3.1
Peatland used for agriculture in selected countries.
Table 3.2
Present and former extent of mires in the non-tropical world.
Table 5.1
Forms of spatial diversity and their application to different organisation and
hierarchical levels in peatlands.
Table 5.2
Key differences between typical K- and r-strategy species.
Table 5.3
Number of bryophyte species found in peatlands compared with the
regional total number of bryophyte species.
Table 5.4
Number of peatland typical vascular plant species in relation to the total
vascular flora in different regions.
Table 6.1
Average carbon stocks of selected natural (pre-anthropogenic) ecosystems
(in t C ha-1) compared to that of the average peatland of the world.
Table 6.2
Age and turn-over time of selected types of fuel. Within parentheses:
maximum age (after Joosten 2004). The distinction between peat, lignites,
and coals is made on the basis of carbon content.
Table 6.3
Carbon balance for a small blanket peatland, Trout Beck catchment in the
Northern Pennines (UK).
Table 6.4
Energy yield and emission factor of typical biomass fuel crops on peat
soil, compared to fossil fuels.
3
10
13
14
23
30
62
65
73
74
101
103
107
109
xxi
Table 7.1
The atmospheric lifetimes and the IPCC (1996) accepted global warming
potentials over different time horizons of GHG associated with peatlands.
Table 9.1
How peatlands compare with other carbon stores.
119
156
Assessment on Peatlands, Biodiversity and Climate Change
1
Introduction
Lead authors: Faizal Parish, Andrey Sirin, David
Lee, Marcel Silvius
The Assessment on Peatlands, Biodiversity and
Climate Change aims to provide a synthesis of
knowledge on the important functions and roles
of peatland ecosystems in relation to
biodiversity conservation, sustainable use and
climate change mitigation and adaptation. It has
been prepared over the period 2005–2007 by a
team of specialists on peatland assessment and
management, biodiversity, climate change and
other fields. This chapter provides an
introduction to the importance of peatlands and
presents more details on the process by which
the assessment was developed.
1.1 Rationale for the Assessment
Peatlands are key natural ecosystems.
Peatlands are one of the most important natural
ecosystems in the world. They are of key value
for biodiversity conservation and climate
regulation, and provide important support for
human welfare. They cover over 400 million ha
in about 180 countries and represent a third of
the global wetland resource. Currently they are
being degraded in many regions as a result of
land clearance, drainage, fire and climate
change. This not only causes a reduction in
biodiversity and direct benefits for people; it
also generates further problems. The protection
and wise use of peatlands should be a global
priority.
Peatlands are wetland ecosystems that are
characterised by the accumulation of organic
matter called “peat” which derives from dead
and decaying plant material under high water
saturation conditions. In peatlands, water, peat
and the specific vegetation that lives in these
ecosystems are strongly interconnected. If any
one of these components is removed, or should
the balance between them be significantly
altered, the nature of the peatland
fundamentally changes.
Figure 1.1: Distribution of mires/peatlands in the world (After Lappalainen 1996 1).
1 Lappalainen E. (Ed.). Global Peat Resources. International Peat Society and Geological Survey of Finland, Juskä.
1
Chapter 1: Introduction
2
There are two major types of peatland: bogs
(which are mainly rain-fed and nutrient-poor)
and fens (which are mainly fed by surface or
ground water and tend to be more nutrient rich).
However there are many different variations of
peatland type, depending on geographic region,
altitude terrain and vegetation. Peatlands may
be naturally forested or naturally open and
vegetated with mosses or sedges. Another
distinction that can be made is between
peatlands where peat is currently being formed
these are known as mires and areas which
formerly had peat formation, but due to human
interventions or climate change, peat is no
longer developing.
Peatlands can be found in all parts of the world,
but their distribution is concentrated in specific
zones. Peat formation is strongly influenced by
climatic conditions and topography. This may
be in areas in northern latitudes or high altitudes
where the temperature is high enough for plant
growth but too low for vigorous microbial
activity. Significant areas of peatlands are also
found in tropical and sub-tropical latitudes
where high plant growth rates combine with
slow decomposition as a result of high rainfall
and water-logged conditions. In some cases
peatlands were formed during wetter climatic
periods thousands of years ago, but peat may no
longer accumulate due to recent climate
changes.
Kenya
Sweden
Canada
Malaysia
Peatlands can be found in almost all geographic
areas – from the Arctic to the Tropics. Suitable
conditions for the formation of peatlands occur
in many parts of a landscape – they can be
found on watersheds and in river valleys,
around lakes, along seashores, in high
mountains and even in the craters of volcanoes.
Peat
PeatPeat
Peat
Peat accumulates where plant
growth exceeds
decay. Water is the most important factor
limiting decay. A permanently high water table
can be provided by high precipitation or by
ground or surface water flow. Diversity in
bedrock and water flow conditions is
responsible for the large va
riety of peatland
types. A second cause of slow decay rates are
the low temperatures that occur at high
latitudes and altitudes.
Peat accumulates at a rate of about 0.5
1
mm per year (or 5-
10m over 10,000 years)
with locally strong variation.
Peat ca
n be formed from mosses, sedges,
grasses, trees, shrubs, or reeds. In northern
regions, mosses are the main peat-
forming
plants while trees are the main species in the
tropics. Most peatlands that exist today
formed in the last 10,00
0 years since the last
ice age.
Assessment on Peatlands, Biodiversity and Climate Change
3
Table 1.1: Peatland Uses & Functions*
Agriculture For centuries, peatlands in Europe, North America and Asia have been used for
grazing and for growing crops. Large areas of tropical peatlands have been cleared
and drained for food crops and cash crops such as oil palm and other plantations in
recent years. However large-scale drainage of peatlands for agriculture has often
generated major problems of subsidence, fire, flooding, and deterioration in soil
quality.
Forestry Many peatlands are exploited for timber harvesting. In northern and eastern Europe
and Southeast Asia, peatlands have been drained for plantation forestry, whereas in
North America and Asia some timber extraction takes place from un-drained
peatlands. The peat swamp forests of Southeast Asia used to be an important source
of valuable timber species such as Ramin (Gonostylus bancanus), but over-
exploitation and illegal trade have led to trade restrictions under CITES (the
Convention on International Trade in Endangered Species, drawn up in 1973).
Peat
Extraction
Peat has been extracted for fuel, both for domestic as well as industrial use,
particularly in Europe but also in South America. Peat extraction for the production of
growing substrates and gardening is a multi-million dollar industry in North America
and Europe. For instance, the Netherlands import 150 million Euros worth of peat
every year as a substrate for horticulture.
Subsistence
use
Peatlands play a central role in the livelihoods of local communities. In the tropics
peatland-related livelihood activities include the harvesting of non-timber forest
products such as rattans, fish, Jelutung latex (a raw material used in chewing gum),
medicinal plants and honey. In parts of Europe and America the collection of berries
and mushrooms is important for some rural populations. All over the world we can
find indigenous peoples whose livelihoods and cultures are sustained by peatlands.
Water
regulation
Peatlands consist of about 90% water and act as vast water reservoirs, contributing to
environmental security of human populations and ecosystems downstream. They play
an important role in the provision of drinking water, both in areas where catchments
are largely covered by peatlands, and in drier regions where peatlands provide limited
but constant availability of water.
Biodiversity
Peatlands constitute habitats for unique flora and fauna which contribute significantly
to the gene pool. They contain many specialised organisms that are adapted to the
unique conditions. For example, the tropical peat swamp forests of Southeast Asia
feature some of the highest freshwater biodiversity of any habitat in the world and are
home to the largest remaining populations of orangutan.
Research,
education
and
recreation
Peatland ecosystems play an important role as archives. They record their own history
and that of their wider surroundings in the accumulated peat, enabling the
reconstruction of long-term human and environmental history. Because of their
beauty and often interesting cultural heritage, many peatlands are important for
tourism.
Carbon
storage
Peatlands are some of the most important carbon stores in the world. They contain
nearly 30% of all carbon on the land, while only covering 3% of the land area.
Peatlands in many regions are still actively sequestering carbon. However, peatland
exploitation and degradation can lead to the release of carbon. The annual carbon
dioxide emission from peatlands in Southeast Asia by drainage alone is at least 650
million tonnes, with an average of 1.4 billion tonnes released by peatland fires. This
represents a major portion of global carbon emissions and causes significant social
and economic impacts in the ASEAN region.
* Each of the uses and functions described above is elaborated in more detail in the different
chapters of the Assessment.
Chapter 1: Introduction
4
Russia
Argentina
Peatlands are closely linked with the economy
and welfare of society. Peatlands are important
to human beings due to their unique role in
environmental regulation, aesthetic values, and
the wide range of goods and services they
provide. Humans have directly utilised
peatlands for thousands of years, leading to
varying degrees of impact. In many areas of the
world, peatlands are beautiful landscapes with a
unique biodiversity. They are deeply integrated
into socioeconomic processes and have become
an historical arena of conflicts and
contradictions in land use. Inappropriate or
short-sighted exploitation of the functions and
services from peatlands have often negatively
affected the livelihoods of local communities
and created broader threats to society through
increasing floods, water shortages and air
pollution from fires.
Peatlands and Climate Change. Peatlands play
an important role in climate regulation. Over
the past 10,000 years peatlands have absorbed
an estimated 1.2 trillion tonnes of carbon
dioxide, having a net cooling effect on the
earth. Peatlands are now the world’s largest
terrestrial long-term sink of atmospheric carbon
storing twice as much carbon as the biomass of
the world’s forests.
However in the last 100 years, clearance,
drainage and degradation of peatlands have
turned them from a net store to a source of
carbon emissions. This, combined with large-
scale emissions from use of fossil fuels and
forest clearance, has contributed to significant
global increases in the concentration of carbon
dioxide and other greenhouse gases – the root
cause of global climate change. Current
predictions by the Intergovernmental Panel for
Climate Change (IPCC) of significant changes
in global temperature and rainfall regimes have
significant implications for peatland
ecosystems. In many cases the predicted
changes are expected to have a negative impact
on peatlands and to exacerbate the rate of
degradation and release of stored carbon.
Peatlands and global environment
conventions. In the global arena of international
environment conventions, peatlands are of
growing concern within the deliberations of the
UN Framework Convention on Climate Change
(UNFCCC), the Convention on Biological
Diversity (CBD), the Convention to Combat
Desertification (UNCCD), and the Ramsar
Convention on Wetlands. The UNFCCC (See
Box below) is primarily concerned with the
implications of peatland loss and its impact on
the global greenhouse gas emissions, as well as
in possible mitigation and adaptation options.
The CBD and the Ramsar Convention have
focused on the importance of peatlands for
biodiversity conservation and the potential for
the sustainable use of biological resources.
Parties to the UNCCD have raised concerns
about the degradation of peatland in the dryland
regions and the loss of associated ecosystem
services such as water supplies. As peatlands
are one single ecosystem, it is important that
their management is addressed in an integrated
manner. The challenge will be to find new
management methods that simultaneously
generate benefits for biodiversity and climate
change, while also addressing the important
needs of local communities.
1.2 Purpose of the Assessment
The Assessment on Peatlands, Biodiversity and
Climate Change aims to provide a synthesis of
knowledge on the important functions and roles
of peatland ecosystems in relation to
biodiversity conservation and sustainable use
and climate change mitigation and adaptation.
One of the most pertinent reasons for the
preparation of the Assessment is because
peatlands are very often inadequately
Assessment on Peatlands, Biodiversity and Climate Change
5
recognised as specific and valuable ecosystems
in relation to either climate change or
biodiversity. The Assessment has brought
together diverse knowledge on peatland
features, functions and services from different
sources, through a multidisciplinary
international task force of peatland, biodiversity
and climate change experts.
Why do we need an assessment? The
assessment aims to contribute to international
decision-making processes relating to global
problems such as biodiversity conservation,
climate change, desertification, pollution,
poverty and health. It will enable the
identification of appropriate management and
adaptation strategies for peatlands which will
bring both biodiversity and climate benefits. It
is intended to provide information to feed into
the deliberations of the global environment
conventions as well as contribute to
deliberations at regional and national levels.
It also provides recommendations on the
development and planning of peatland use that
could be used as an information source in
policy making and in the drafting of laws and
regulations. For some countries with significant
areas of peatland, this Assessment could be
used to provide guidance and reference in the
development of sustainable strategies for
peatland management and to help foster
understanding about the need for stakeholder
interaction related to peatland management.
Recognition of the Assessment process. In
February 2004, the Seventh Conference of the
Parties