Vegetation Carbon Reserve and Its Relationship with Climatic Factors of Grassland System in Tibet

On the basis of far-flung collecting of databases in Tibet grassland and making use of average car- bon density method to assess 17 vegetation carbon reserve of grassland ecosystem and analyzed its relation- ship with climatic factors.The results showed that:(1)The total area of 17 grassland vegetations was 8 205.194×10~4 hm~2,the grassland vegetations total carbon store was 189.367 TgC,the average carbon densi- ty of grassland vegetations was 2 307.892,between 395.977 kg/hm~2 and 20 471.161 kg/hm~2 changing,and existed diversity in different grassland vegetations.(2)From the regional distributing,Ali,Naqu and Rikaze not only the mainly grassland regions that proportion was 84.156% of Tibet grassland but also was the most- ly carbon pool of Tibet grassland ecosystem carbon store,which vegetations carbon store proportion was 60.278% of all 17 vegetations carbon store.(3)Used stepwise regression and principal components method to analyze the factors of climate to compact on the Tibet vegetation carbon reserve,and showed that the pre- cipitation function bigger than temperature factors.