Global Wetlands' Soil Organic Carbon Pool Estimates Based-on GlobeLand30 And Its Distribution

Warming of the climate system is unequivocal,and it is mostly related to greenhouse gases increasing,like CO₂,CH₄,N₂ O,etc.Due to fossil fuel burning and land use change,greenhouse gases in atmosphere has increased a lot since pre-industrial times.Wetland,together with forest and marine are the most important ecosystems in the world,and it's the main methane emissions place.Wetlands,with human activity and climate change,continue to decline globally,both in area and quality,then it becomes the carbon source and releases CO 2 into the atmosphere.For study on global carbon cycle,it's important to estimate and monitor the soil organic carbon stock in global wetland in the long term.Meanwhile,accurate estimation of wetland carbon pool is a prerequisite for wetland resource conservation and implementation of carbon sink enhancement plans.In this text,we firstly utilized the Globe Land30 to estimate soil organic carbon pool in global wetland.After preprocessed the HWSD data,the oriented-object nearest neighbor method was used in wetlands' soil organic carbon calculation for 691 mapsheets of Globe Land30.We,finally,analyzed and mapped the wetlands' soil organic carbon pool and density in basin-,country-/region-,continent-,global level respectively.Primary results are as follows:1).There is 102.76 Pg C in soils?for depth 0-100 cm?of global wetlands for 2010,about 4%¹0% of global soil organic carbon stock,and its' density is 252.33 t/ha;2).Marsh and forested wetland are the main pool,and its' soil organic carbon of wetland is over 80% of global storage totally;3).The spatial distribution of wetlands' soil organic carbon is uneven,there is 93.26 Pg C in the TOP 10 countries,approximately 91% of global wetlands' soil organic carbon pool;4).Latitudinally,most of wetlands' soil organic carbon is stored in Northern Hemisphere,while the wetlands' soil organic carbon stock of Eastern and Western Hemisphere is roughly equal;5).The soil organic carbon storage of wet land in continents is different from each other,Europe and North America is the most and second pool respectively,followed by South America,Africa,Asia,Oceania;6).There is higher storage capacity in cold and fully humid climate zone like Marine West Coast Climate,storing approximately 75% of global wetlands' soil organic carbon,and its' soil organic carbon stock of wetland,together with Tropical Wet Climate and Humid Subtropical Climate,is 82.8% of global pool;7).Basin affects the spatial distribution of wetlands' soil organic carbon too,there is about 34.79% of global pool and 35.75 Pg C totally in 14 international important basins?TOP 10 basins are included?.