Dynamic and natural driving factors of vegetation carbon sink in Hunan Province
Net ecosystem productivity(NEP)is recognized as an important characteristic quantity of ecosystems and a physical quantity of carbon exchange between terrestrial ecosystems and the atmosphere.Utilizing MODIS NPP and meteorological data,this study estimated the vegetation NEP in Hunan Province from 2000 to 2020 using a soil microbial respiration model.Furthermore,this study analyzed the dynamic characteristics of vegetation carbon sink through trend analysis,variation coefficient,and standard deviation ellipse methods,followed by a quantitative assessment of the impacts of natural factors on vegetation carbon sink using geographical detectors and correlation analysis.The results indicate that the annual multiyear average of vegetation carbon sink in Hunan Province was 603.01 gC·m-2·a-1.The vegetation carbon sink presented a spatial distribution pattern of higher values in the south and west and lower values in the north and east,decreasing gradually from southwest to northeast.From 2000 to 2020,the average trend coefficient of vegetation carbon sink was 2.97 gC·m-2·a-1,trending upward overall.The coefficient of variation was primarily characterized by small fluctuations and fairly small fluctuations,while areas of great fluctuations are mainly scattered around certain cities,which are more susceptible to natural or anthropogenic disturbances.The variations in vegetation carbon sink in Hunan Province result from multiple factors,with the explanatory power of various factors decreased in the order of altitude,slope,temperature,precipitation,and slope.Both altitude and slope exhibited strong explanatory power regarding the spatiotemporal distribution of vegetation carbon sink in Hunan Province,while temperature and precipitation demonstrated weaker explanatory power.Areas where vegetation carbon sink was positively correlated with temperature and precipitation accounted for 75.13％and 73.11％of the total vegetation area,respectively.
vegetation carbon sinknet ecosystem productivity(NEP)dynamic changedriving factorsHunan Province
万方数据
维普
