摘要
Soil organic carbon (SOC) storage under different types of vegetations in China were estimated using measured data of 2 440 soil profiles to compare SOC density distribution between different estimates, to map the soil organic carbon stocks under different types of vegetation in China, and to analyze the relationships between soil organic carbon stocks and environmental variables using stepwise regression analyses. Soil organic carbon storage in China was estimated at 69.38 Gt (10 15 g). There was a big difference in SOC densities for various vegetation types, with SOC distribution closely related to climatic patterns in general. Stepwise regression analyses of SOC against environmental variables showed that SOC generally increased with increasing precipitation and elevation, while it decreased with increasing temperature.Furthermore, the important factor controlling SOC accumulation for forests was elevation, while for temperate steppes mean annual temperature dominated. The more specific the vegetation type used in the regression analysis, the greater was the effect of environmental variables on SOC. However, compared to native vegetation, cultivation activities in the croplands reduced the influence of environmental variables on SOC.
Soil organic carbon (SOC) storage under different types of vegetations inChina were estimated using measured data of 2440 soil profiles to compare SOC density distributionbetween different estimates, to map the soil organic carbon stocks under different types ofvegetation in China, and to analyze the relationships between soil organic carbon stocks andenvironmental variables using stepwise regression analyses. Soil organic carbon storage in China wasestimated at 69.38 Gt (10^(15) g). There was abig difference in SOC densities for variousvegetation types, with SOC distribution closely related to climatic patterns in general. Stepwiseregression analyses of SOC against environmental variables showed that SOC generally increased withincreasingprecipitation and elevation, while it decreased with increasing temperature. Furthermore,the important factor controlling SOC accumulation for forests was elevation, while for temperatesteppes mean annual temperature dominated. The more specific the vegetation type used in theregression analysis, the greater was the effect of environmental variables on SOC. However, comparedto native vegetation, cultivation activities in the croplands reduced the influence ofenvironmental variables on SOC.
基金
Project supported by the Knowledge Innovation Program of Chinese Academy of Sciences (No. KZCX2-413)
the National Key Basic Research Support Foundation of China (No. G1999011801).
