成都平原典型秸秆循环利用模式的生命周期评价

Life Cycle Assessment of Three Typical Straw Recycling Modes in Farmlands of The Chengdu Plain

运用生命周期评价理论,对成都平原典型秸秆循环利用模式的环境影响进行评估,探讨了不同农田生产模式的资源消耗与环境影响特征。结果表明:"稻–(菌废料)–麦"模式(FR模式)的温室气体排放总CO2当量为1.44×107 g CO2-eq,为3种模式中最小值,而"稻–(秸秆)–麦"模式(CFS模式)排放量最高;与传统农田生产模式(CF模式)比较,CFS和FR两种秸秆循环利用模式的环境酸化潜力,分别由6.44×104 g SO2-eq降至3.10×104 g SO2-eq和1.21×104 g SO2-eq,分别下降了51.85%和81.21%;CFS和FR模式的水体富营养化潜力相比CF模式,分别降低了24.21%和52.28%。从CF、CFS到FR模式,土壤毒性潜力逐渐下降,但3种模式中土壤重金属的残留比例仍然较高。3种秸秆循环利用模式的农作系统是造成潜在气候变暖、环境酸化、富营养化和土壤毒性的主要环节。由此,"稻–(菌废料)–麦"模式有利于节能减排,缓解全球气候变暖,降低环境影响潜力。

In this paper the life cycle theory was applied to assess the environmental impact of three straw-recycling modes in farmlands in the Chengdu Plain. The results showed that the total CO2 equivalence of greenhouse gas（GHG） emissions from the rice-wheat rotation with mushroom residues applied（the FR mode） was 1.44×10^7 g CO2-eq, and was the lowest amount among the three straw recycling modes. While, the CO2 equivalence of GHG emissions from the rice-wheat rotation fertilized with crop straws applied（CFS mode） was the highest. Compared with the traditional agricultural production mode （chemical fertilizer application （CF mode））, the environmental acidification potentials of the CFS and FR modes were decreased from 6.44×10^4 g SO2-eq to 3.10×10^4 g SO2-eq and to 1.21×10^4 g SO2-eq, and decreased by 51.85% and 81.21%, respectively. The water eutrophication potentials of the CFS and FR modes were also decreased by 24.21% and 52.28%, respectively. The sequence of the soil toxicity potentials were in the order of CF