SMOKE ON WATER

Why peatlands are important The previous section introduced the subject of peatlands and pointed to the enormous benefits that undrained peatlands deliver. Besides climate benefits, these unique wet environments support a huge range of specialized plant and animal species, including many that are rare or endangered. Peatlands also support the livelihoods of millions of people and, because they act like giant filters, they help control and purify water.

To get there, policymakers need to recognize the usefulness of peatland conservation and restoration as a way of mitigating climate change. Supporting unique and critically threatened biodiversity Peatlands are home to unique biodiversity and many specialized and endangered species have adapted to live there. For example, about 37 percent of all vascular plants in the peatlands of the Yamal Peninsula in Siberia and 10 percent of all fish species within Peninsular Malaysia are only found in peatland ecosystems (Parish et al., 2008; Joosten et al., 2012). Tropical peatlands support a wide range of unique, threatened and/or endemic species, including 31 species of tropical lowland rainforest trees known as dipterocarps across Southeast Asia (Joosten et al., 2012) and five of the six species of great ape. The latter are the western gorilla ( Gorilla gorilla ), chimpanzee ( Pan troglodytes ), bonobo ( Pan paniscus ), Bornean orangutan ( Pongo pygmaeus ) and Sumatran orangutan ( Pongo abelii ). The orangutans are highly threatened, in part due to peatland degradation and conversion (Ancrenaz et al., 2016; Singleton et al., 2016). The breeding habitat of the Aquatic warbler ( Acrocephalus paludicola ), Europe’s only globally threatened songbird, is restricted to specific peatland habitats in central and eastern Europe (Tanneberger et al., 2011).

Peatlands form where climate, bedrock and relief create areas with permanent water saturation. They either develop in shallow waters over layers of lake sediments (this is called terrestrialisation) or directly on mineral soils (known as paludification). There are two major types of peatlands: 1. Bogs which are only fed by rain. Bogs are therefore nutrient poor, acidic, and often elevated over the surrounding mineral soil, and 2. Fens which are also fed by water coming from mineral soil/bedrock and are usually less acid and richer in nutrients. Carbon storage Peat is formed when organic matter accumulates faster than it decomposes due to the lack of oxygen in waterlogged conditions. Peatlands are the most carbon dense of any terrestrial ecosystem in the world (Joosten & Couwenberg, 2008; Urák et al., 2017). Ecosystems sequester and store carbon in different ways, such as in living biomass, litter or humus in upper layers of mineral soils. Most of these carbon pools are not permanent and carbon will be released back to atmosphere over relatively short cycles. Beside these pools, however, the peat layer of peatlands provides – if not disturbed – a unique, permanent store for carbon. Keeping this carbon in the ground is crucial if the world is to meet the target of the Paris Climate Change Agreement to keep the global average temperature increase under two degrees Celsius. The key benefits that peatlands provide include:

Peatlands are also home to many species of high economic value, including hardwood trees such as ramin ( Gonystylus bancanus ).

Sumatran orangutan

Aquatic warbler

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