An appraisal of global wetland area and its organic carbon stock

Wetlands are among the most important natural resources on earth. They are the sources of cultural, economic and biological diversity. With their wealth of stored carbon, wetlands provide a potential sink for atmospheric carbon, but if not managed properly could become sources of greenhouse gases (GHGs) such as carbon dioxide and methane. Two important long-term uncertainties have initiated much debate in the scientific community. These are global wetland area and the amount of carbon stored in it. Compilation of relevant databases could be useful in setting up a long-term strategy for wetland conservation. It has been difficult to estimate the net carbon sequestration potential of a wetland, because the rate of decomposition of organic matter and the abundance of methanogenic micro-organisms and fluxes from the sediment are extremely complex, and there are often gaps in relevant scientific knowledge. The present discussion on density distribution of soil organic C in global wetlands could well be instrumental in formulating efficient strategies related to carbon sequestration and reduction of GHG emissions in wetland ecosystems. Effective assessment of wetlands will only take place when the available information becomes accessible and usable for all stakeholders.