基于碳足迹分析国家级重点生态功能区农田种植业特征

Analysis on the Characteristics of Farmland Planting in the National Key Ecological Functional Area Based on Carbon Footprint

小尺度农田生态系统碳足迹的研究可为当地低碳农业的发展提供科学依据。基于碳足迹视角,以国家级重点生态功能区山西偏关县为例,根据主要投入要素的碳排放系数和各种作物的碳吸收率,利用SPSS软件回归分析了2007—2016年研究区农作物的碳吸收对农业化学物质及能源投入碳排放的消纳情况。结果表明,偏关县农田种植业的碳平衡处于碳生态盈余状态,粮食作物在种植业中占比较大,玉米是影响农作物固碳的主要因素,但是变幅不大,而大豆固碳能力逐年增长,氮肥、农膜、耕作耗能、秸秆焚烧是影响碳排放的主要因素,其中,氮肥碳排放年均贡献率为45%;农膜碳排放近10 a增长5%。因此,碳生态盈余状态并不能掩饰化学物质和能源投入所引发的不可再生资源年损耗的增加和农业面源污染潜在风险的加剧。

The study on the carbon footprint of small scale farmland ecosystem can provide scientific basis for the development of low carbon agriculture in the area. The paper based on the perspective of carbon footprint, taking Shanxi Pianguan county, a national key ecological functional area, as an example, according to the carbon emission coefficient of the main input factors and the carbon absorption rate of various crops, analyzed the discharge situation of the carbon absorption of crops to carbon emissions from the agricultural chemical substances and energy inputs by using SPSS software in 2007-2016 years. The results showed that the carbon balance of Pianguan county plantation was in the state of carbon ecological surplus, food crops in the farming industry accounted for a large proportion, corn was the main factor affecting carbon sequestration, but it changed not much. However, the carbon sequestration capacity of soybean increased year by year. Nitrogen fertilizer, agricultural film, tillage energy and straw burning were the main factors which affected carbon emissions. The annual contribution rate of nitrogenous fertilizer to carbon emissions was 45%, and the carbon emission of agricultural film increased 5% for 10 years. Therefore, the state of carbon ecological surplus cannot conceal the increasing annual loss of non-renewable resources caused by the increasing of agricultural chemical substances and energy investment and the potential risk of agricultural non-point source pollution.