我国西部地区种植业碳收支分析

Evaluation on Carbon Balance of Crop Production in Western China

随着我国西部地区农业的快速发展,碳排放对生态环境的影响不断变化。因此,评价西部地区种植业生产过程中碳收支情况,对于该地区低碳农业的发展有重要意义。基于我国西部12个省份1997-2012年农业相关统计数据,分析这些地区种植业生产系统的碳排放量和碳吸收量变化,结果表明：西部地区各省份种植业生产系统的碳排放量和碳吸收量均呈不断上升的趋势,年均增长量分别为368.8万t CO2-eq和4 138.3万t CO_2-eq。西部地区各省份种植业的平均碳排放量和平均碳吸收量分别介于51.7万～3 314.7万t CO_2-eq和524.7万～28 715.1万t CO_2-eq。在总的碳排放构成中,化肥的使用是种植业生产系统投入品碳排放的最大构成部分,平均占到45.7%,其次为农用柴油和灌溉。总体上,我国西部地区种植业生产系统的碳收支处于碳盈余状态,但各省份间差异较大。

With the rapid development of agriculture in western China,influences of carbon（ C） emissions on corresponding ecological region are elevated. Therefore,it is crucial to assess the C balance on crop production in Western China for seeking low-carbon emission agriculture development strategies in this region. Based on agriculture related statistical data from 12 provinces in Western China during 1997- 2012,this study evaluated the changes in quantity of C emission and fixation of crop production in those regions. The results indicated that the amounts of C emission and fixation of crop production system of each province in Western China increased with the year. The annual average increase was 3.7×10^6t CO_2-eq and 41.4×106t CO_2-eq for C emission and fixation,respectively. In addition,the average rate for C emission and fixation ranges from 51.7×10^4～ 3 314.7×10^4t CO_2-eq and 524.7×10^4～ 28 715.1×10^4t CO_2-eq,respectively. Among C emission inventories,chemical fertilizer application was the largest component occupied 45. 7% of the total emission averagely,followed by fuel consumption of farming diesel and irrigation.Generally,the C balance of crop production in western China was surplus in fixation,but still observed variations varied greatly among provinces.