Peat soils as hotspots in agricultural climate policies Hans Joosten Greifswald University
In living peatlands (mires): Plant production > decay Peat accumulates Positive Carbon-balance
Peat accumulates during thousands of years and stores concentrated carbon in thick layers
Peatlands are found in almost every country. Worldwide: 4 million km 2
Also important in the EU
The Cinderella Syndrom The importance of peatlands for climate change mitigation (and adaptation!) has long been overlooked
Natural peatlands remove CO 2 and emit CH 4. In balance, they are climatically neutral
Their importance lies in their carbon stock: peatland is peat-land and peat is largely carbon
Peatlands are the most space-effective carbon (C) stocks of all terrestrial ecosystems.
In the boreal zone peatlands contain 7 x more carbon per ha than other ecosystems, in the tropics 10 x
While covering only 3% of the World s land area, peatlands contain > 500 Gt of carbon in their peat.
This is equal to all terrestrial biomass, and 2 times the carbon stock in the total forest biomass of the world
They hold in average per ha even twice the carbon content of the mammoth forest in California
When drained, the peat oxidizes and peatlands become vigorous sources of carbon dioxide (and nitrous oxide)
in wet peatland in drained peatland CO 2 O 2 CH 4 O 2 CO 2 N 2 O plants peat C, N, P peat P, K, N
Globally peatlands have turned from C-sink to C-source
Globally, degraded peatlands emit 2 Gtons CO2 yr-1
0.3 % of the land surface is responsible for 6 % of the total global anthropogenic CO 2 emissions
CO 2 emission Main peatland emission hotspots: SE Asia and EU
Top peat CO 2 emittors (Mt per yr) The top (excl. extraction and fires) include Indonesia 500 European Union 174 Russian Fed. 161 China 77 United States 67 Finland 50 Malaysia 48 Mongolia 45 Belarus 41 Germany 32 Poland 24 Uganda 20 Pap. New Guinea 20 Iceland 18 Sweden 15 Brazil 12 United Kingdom 10 Estonia 10
Annual peat-co 2 -emissions Mton Cause Mio CO 2 Ha 600 Drainage SE Asia 12 400 Peatfires SE-Asia 500 Other agriculture 25 130 Forestry 12 60 Peat extraction 2 20 Urbanisation, infrastructure 1
Drained peatland subsides, becomes wetter and requires deeper drainage, leading to further subsidence
the devil s cycle of peatland utilisation wet problem sites wetting drainage subsidence
Bavaria: 3 m loss since 1836 UK: 4 m loss since 1870
The Netherlands: bogged down by 1000 yr of peatland Nether-lands drainage, now half the country below sea level
Rapid soil degradsation in more continental climates: after 30 years no agriculture possible anymore.
Drained peatlands are the environmental black sheep of agricultural land use
forestry agriculture Electricity and district heating Industry Traffic unused Small consumers Peatlands Emissions in my federal state Mecklenburg- Vorpommern
Federal state Emissions from drained peatland (% of emissions without land use) Method source Schleswig- Holstein Mecklenburg- Vorpommern 9 % GEST Jensen et al. 2010 37% GEST MLUV MV 2009 Brandenburg 36 % GEST Landgraf 2010 In our region (but similarly in many EU regions!) peatlands emit substantial CO 2
The most important peatland emittor is agriculture
1000 kg CO 2 ha 60 50-1 y -1 40 30 20 10 0-140 -120-100 -80-60 -40-20 0 20 40 mean annual water level (cm) Every 10 cm deeper water level leads to 9 ton (!) extra CO 2 emission
Currently peatlands are deeper drained for cultivating biofuels, all over the world
Mays for biogas: biofuel is climatically accounted, peat carbon losses not
From a climate point of view it is better to burn the peat directly than to cultivate biofuels on drained peatland
biofuels from drained peatlands emit much more CO 2 than burning coal
One hectare of drained peatland emits per year as much CO 2 as flying 3 x around the globe!
Most emissions from agricultural land come from drained peatland
Conventional peatland agriculture imitates dryland
although draining, plowing and fertilizing of peatland are the best ways to increase emissions
EU money maintains these practises Direct payments maintain drainage of peatland without utilisation of biomass Agri-environment schemes stimulate organic agriculture on deeply drained grassland Renewable Energy Law forsters using drained peatland for bio-energy crops EU supports land use on drained peatland and frustrates sustainable land use options
We must get out of this devil s circle and develop paludiculture!
Paludiculture is agriculture on wet/rewetted peatlands
Paludicultures reduce peatland emissions and produce
Planting reed on drained peatland before rewetting
Harvesting of wet peatland biomasse
Reed cultivation: biomass ánd peat accumulation
Roof reed: quality product
Roof reed: quality product
Energy use
biogas, briquets, pellets
In Belarus we convert a briquet factory from peat to biomass sustainable fuel from same (wet!) peatland
After vti 2008, WBA 2007 Avoided emissions (t CO 2 eq/ha) from bio-fuels from mineral soils compared to rewetted peatland Re-wetted peatlands Wood chips (short rotation forestry) 10-25 t Re-wetting peatlands is efficient land use option!
Reed: production of insulation mats
Reed and Cattail insulation boards
Alder cultivation on rewetted fens
Alder cultivation: biomass ánd peat accumulation
Alder wood: quality product
Grasses/sedges for second generation biofuels
Cultivation of peatmoss as alternative for peat in horticultural substrates.
Paludiculture Most paludicultures can compete with normal drainage based agriculture. But substantial market distortion because of agricultural subventions ( paludiculture is no agriculture ). Paludiculture is a cheap and effective way to reduce emissions
Needed: Investment grants (for land reallotment and hydrological restructuring, acquisition of adapted machinery, development of production lines, product placement ) Agricultural consultation for peatland use and paludiculture Research Ban on ploughing of grassland on peat
Needed: Direct payments also for paludicultures
Needed: new technologies: our new paludi-bully
Needed: Agri-environmental schemes for raising water levels (> 20 cm below surface) Very positive for climate But also for water management and biodiversity
Peatlands must be wet!