山东省农田生态系统碳源、碳汇及其碳足迹变化分析

依据2002—2013年山东省17地市农业投入、播种面积以及作物产量等统计数据,对全省各地市农田生态系统进行碳源、碳汇估算,从中分析其变化规律,并探讨造成碳源、碳汇时空变化的影响因素。结果表明:山东省农田系统具备较强的碳汇能力,碳吸收量明显高于碳排放量,两者的总量之比为4.32∶1;碳吸收量和碳汇量呈增加趋势,碳排放量和碳足迹呈降低趋势;农田生态系统表现出较大的碳生态盈余,碳足迹占同期耕地面积的比值呈现降低趋势,2002年为27.71%,2013年为20.96%;17地市之间单位面积碳汇量和单位面积碳足迹存在明显差异,2013年单位面积碳汇量最高的为德州市(6.20t/hm~2)、最低为威海市(3.02t/hm~2),单位面积碳足迹最高的威海市为0.26hm~2/hm~2、最低的泰安市为0.08hm~2/hm~2。

Analysis of ecosystem carbon sources/sinks and carbon footprint in farmland ecosystem of Shandong Province

According to the statistical data (agricultural investments, crops areas and crops output) of 17 cities from 2002 to 2013 in Shandong Province, the farmland ecosystem carbon and carbon sinks and its changing rules of entire province was estimated and the influencing factors which caused carbon sources and carbon sinks'' spatial and temporal changing were explored.The results show that:Agricultural system in Shandong Province holds a powerful carbon sink capacity, the amount of carbon sequestrations is significantly higher than that of carbon emissions, and the rate of the total amount between them is 4.32:1;The amount of carbon sequestration and carbon sinks is apparently displaying an increasing tendency, the amount of carbon emissions and carbon footprint shows a decreasing tendency;The farmland ecosystem displays a promising carbon ecological surplus, while the ratio between footprint area and farmland area is dropping, which was 27.71% in 2002 and 20.96% in 2013;There are obvious differences among the 17 cities on per unit area of carbon sinks and carbon footprint.In 2013, the highest amount of per unit area carbon sinks is Dezhou City (6.20 t/hm²);the lowest is Weihai City (3.02 t/hm²).The highest per unit area of carbon footprint is Weihai City (0.26 hm²/hm²), the lowest is Tai''an City (0.08 hm²/hm²).