Impacts of Climate Change on Productivity of Forests in China I.Geographic Distribution of Actual Productivity of Forests in China

The initial research results of the project "impacts of climate change on productivity of forests in China" was presented in the present paper.In view of the relationship between productivity and environment,the characteristics of geographic distribution of primary productivity of forests in China were analyzed by comparison,and the relationship between stratal productivity,environmental conditions,species productivity and community structure were explored.The results showed net primary productivity,annual litterfall decreased gradually with the increase of latitude and altitude,whereas a reverse trend occurred in the standing crop of litter,which is heavily determined by temperature and precipitation regimes;there was no significant difference in the standing crop of biomass among various forest vegetations distributing in different physiographical zones,but mature natural forests with a complicated structure and high species diversity usually possessed a relatively larger amount of biomass;stratal productivity exhibited different variations in reciprocal exclusions or complements under different environmental conditions;species productivity varied with community structure,and it represented its role and position within a community,and therefore determined traits and nature of a community.