The Impacts of Climate Change on Net Ecosystem Production in China
气候变化对净生态系统生产力的影响

Many factors can impact RH, but up to now most of the researches only consider the climatic factors such as temperature and soil moisture or precipitation. The impacts of soil properties on RH have been ignored, so the models' effect is not as good in large area where soil properties vary greatly as in small area where soil properties vary less. The coefficient of soil heterotrophic respiration reflected the influence of soil properties on RH. Based on carbon balance equations of ecosystems, the 1-km resolution's soil heterotrophic respiration coefficient (aij) in China has been calculated by using net primary production (NPP) of ecosystems and observed climate data. The results show that the value of aij as a whole, is larger in Southeast and Northeast China than that in Northwest China. Compared with the NPP's distribution throughout the country, the value of aij in most parts of Southeast China is not large, but it is large in vast area of Northeast and East China, which indicates that the soil heterotrophic respiration has great increase potential in these regions if climate becomes favorable. And then, the authors simulate the carbon flux change between terrestrial ecosystem and atmosphere on the hypothesis of climate change, the average temperature is 1.5oC higher and average precipitation is 5% more. The results show that both fluxes from atmosphere to terrestrial and from terrestrial to atmosphere increase. The rate of average increase of NPP and soil heterotrophic respiration is about 6.2% and 5.5% respectively. The most powerful natural ecosystem which could accumulate carbon is needle-leaved deciduous forest, and the most powerful agricultural ecosystem which could accumulate carbon is one crop per year. On the contrary, the double cropping rice followed by a cool-loving crop per year and the double cropping rice followed by a thermophilous crop per year are potential carbon sources.