The Study Of Forest Organic Carbon Spatial Varition And Impact Factors In Zhejiang Province

Carbon dioxide （CO₂） is one of the so-called ‘greenhouse gases’ which are responsible forabsorbing energy from the sun, leading to warming of the Earth’s atmosphere–the ‘greenhouseeffect’.Forest ecosystems have been increasingly paid more and more attentions due to the roles insequestration and storage of carbon with increasing concentrations of greenhouse gas in theatmosphere during recent ecades.In order to mitigate climate change, more C should besequestered in forest ecosystems and strategies for an adapted forest management aresought, thus,further work is needed for a better understanding of carben storage in forest systems Theobjectives of this study were （1）to investigate organic carbon storage in the soils underdifferent forest stands in Zhejiang province，（2）to compares soil organic carbon densities of mainforest stands，and（3）to determine spatial distribution and total storage of soil carbon under forestsystems in ZheJiang province.（1） For0-10cm、0-30cm、0-100cm soil depth, the lowest soil organic carbon density wasboth occurred on red bayberry gardens（2.77t/ha、6.56t/ha、10.03t/ha）,whereas the highest one bothoccurred on Masson pinestands（174.60t/ha、332.43t/ha、869.55t/ha）.（2） Organic carbon densities in the0-10cm soil depth of mixed coniferous and broad leafforests，broad leaf forests，Moss bamboo forests，Chinese firforests, and Masson pine forestsaccornted for32.1，33.7，26.7，29.0and33.8%of1m soil depth,respectively. Soil organic carbondensities of5kinds of forests decrease with soil depth, but the decreased rates of soil organiccarbon densities for mixes coniferous and broad leaf forests and broad leaf forests were greaterthan for Moss bamboo forest Chinese firforests and Masson pine forests.（3） Organic carbon densities in the1m soil depth of5kinds of forests decrease in the order:：broad leaf forests （12.69kg/m2）>Chinese firforests（11.82kg/m2）>Moss bamboo forests（11.01kg/m2）>Mixed coniferous and broad leaf forests（10.73kg/m2）>Masson pine forests （9.79kg/m2）.（4） Spacial distribtion of soil organic carbon densities in0¹0,0³0or0¹00cm soildepth under the forests showed the following raw: Qiandao Lake district in Chuen county> Lishuidistric> Wenzhou distric>Taizhou distric≈Nibo distric> Shaoxing distric.> Jinhua distric.Organic carbon density and total carben storage in the1m soil under all forests in ZheJiangprovirnce were10.764kg/m2and6.48×108t, respectively. （5） Soil organic carbon content in surface soils under the forests was significantly correlatedwith alkali-hydrolyzed nitrogen, and available potassium（P＞0.01）.Available potassium contentinsurface soils under the forests was significantly correlated with alkali solution ofalkali-hydrolyzed nitrogen, available phosphorus and pH（P＞0.01）.（6）Correlative analysis for soil organic carbon in the1ha forest soil showed thatsoil organiccarbon was significantly correlated with elevation （0.281, P>0.01） and with slopegradient（-0.0759, P>0.05）.but not with slope direction（-0.039, P<0.05），which suggesting that theelevation is a main factor affacting soil organic carbon.（7） Organic carbon storage in the forest soils was positive significantly.correlated shrubcoverage rates, mean geights of shrubs, and average ages of the forests （P<0.01）.