我国农田生态系统碳蓄积及其变化特征研究

Carbon fixation by farmland ecosystems in China and their spatial and temporal characteristics

对我国近20年来农田生态系统C蓄积的时空变化特征进行估算分析结果表明,我国农田生态系统近20年来C蓄积总量持续增大,主要是由于单位面积C密度持续增大。农田C密度高值区主要分布在我国东部地区且多>3t/hm2,低值区主要分布在我国北方农牧交错带地区且普遍<1t/hm2。而科学管理作物残余物是增强农田生态系统C蓄积能力的关键。

The amount of carbon fixation and its spatial and temporal characteristics by farmland ecosystem are estimated and analyzed.The results show that the total quantities of carbon fixation increases gradually in the past two decades because the carbon density per hectare increases.The East China belongs to the area of the high value (over (3t/hm^2)) and the agropastural ecotone in North China has the low value of carbon density which is less than (1t/hm^2).Thus,the crop residue management is the key issue for enhancing carbon sequestration.