Carbon Sequestration in Wetland Soils

摘要: Crops adapted to wetland conditions such as rice (Oryza sativa L.) have been cultivated on waterlogged anoxic soils for millennia. Grazing of livestock is another important agricultural activity in wetlands. Wetlands including peatlands may cover up 26.9 million km2 globally, and wetlands contain 158 Pg soil organic carbon (SOC) 1 m depth, but knowledge distribution, extent, volume needs be strengthened. Peatlands are organic-rich ~4 with large areas the Northern Hemisphere. Over centuries millennia, accumulated globally >750 (C) peat, sometimes several meters depth decomposition rates greatly reduced under wet acidic conditions. Thus, while covering only 3% global ice-free land area store more than one-fourth SOC stock. Stocks northern alone >600 C, their utilization agriculture release amounts dioxide (CO2) by peat oxidation. For example, ~1 CO2 emitted annually from drained (including emissions fire), high especially tropical regions often cultivation oil palms (Elaeis guineensis Jacq.). Further, cumulative net peatland use estimated at 6 C period 1850–2015. also among major biogenic methane (CH4) sources contributing about 30% total CH4 will increasingly contribute projected climate change. losses increase future because sustainable intensification (SI) should applied reduce Options include, restoring land-use types flooded conditions, improved fertilizer water management paddy fields, breeding new crop cultivars better In this respect, paludiculture promising a suitable practice cobenefit sequestration. This chapter begins general overview peatlands. Then, balance discussed detail. Agricultural presented following section. The final section discusses options ‘climate-friendly’