基于LCA的不同间作体系产量优势及温室效应研究

为了探究间作体系对农田生态系统温室效应和产量优势的影响,本文选用小麦/蚕豆和玉米/马铃薯间作种植体系,通过为期2年的田间小区试验,采用生命周期评价法(LCA),以小麦/蚕豆间作和小麦单作、玉米/马铃薯间作和玉米单作为研究对象,以生产1 000kg作物为评价的功能单元,建立农资系统和农作系统生命周期资源消耗以及温室气体排放清单,研究了不同种植体系的作物产量、全球增温潜势和能源消耗等指标的差异。结果表明:与单作小麦相比,间作小麦两年的产量分别增加18.04%和39.94%;与单作玉米相比,间作玉米的产量分别增加2.65%和23.16%;小麦/蚕豆间作系统两年平均增幅高于玉米/马铃薯间作系统。小麦/蚕豆间作的土地当量比两年均大于1,玉米/马铃薯间作的土地当量比仅有1年大于1。与单作小麦相比,两年间作小麦的全球变暖潜值分别降低15.28%和28.53%,能源消耗分别减少15.29%和28.53%;与单作玉米相比,间作玉米的全球变暖潜值分别降低2.61%和19.05%,能源消耗分别减少2.61%和18.83%。小麦/蚕豆间作的间作产量优势优于玉米/马铃薯,但玉米/马铃薯间作的增温潜势低于小麦/蚕豆间作。合理间作具有显著增产效应,同时可以降低温室效应以及能源消耗,以更低环境代价获得作物高产高效。

Yield improvement and greenhouse effect of different intercropping systems based on life cycle assessment

Global warming has become the most pressing problem affecting the ecological environment, and the greenhouse gases (N₂O, CH₄, and CO₂) produced due to agricultural practices are one of the factors that cannot be neglected. Establishing different planting models and production management measures, reducing energy consumption and greenhouse gas emissions in the farmland ecosystems, and achieving high yields and efficiency in an environment friendly manner are important safety strategies for sustainable agricultural development. In this study, the effects of intercropping systems on greenhouse gas emission and yields were explored in the farm ecosystems for the wheat/faba bean and corn/potato intercropping systems. Two years of research using the life cycle assessment (LCA) method has produced data that compare the differences in crop yield, global warming potential, and energy consumption in the intercropping and monocropping systems. The wheat/faba bean intercropping and wheat monocropping system as well as the corn/potato intercropping and maize monocropping systems were used as research objectives and a production unit of 1 000 kg was evaluated as the functional unit. The agricultural capital system, life cycle resource consumption, and greenhouse gas emission inventory for agricultural resources systems and farming systems under different planting models were established; and monocropping and intercropping environmental impact assessments was conducted. The results showed that compared to the yield of monocropped wheat, the yield of intercropped wheat increased by 18.04% and 39.94%, respectively, in 2014 and 2015. Besides, the global warming potential of intercropped wheat decreased by 15.28% and 28.53%, while the energy consumption decreased by 15.29% and 28.53%, respectively, in 2014 and 2015. Furthermore, compared with monocropped maize, the yield of intercropped maize increased by 2.65% and 23.16%, whereas the global warming potential of intercropped maize decreased by 2.61% and 19.05%, respectively, in 2014 and 2015. In addition, energy consumption decreased by 2.61% and 18.83%, respectively, in 2014 and 2015. Compared with monocropping, reasonable intercropping significantly increased the crop yield while reducing greenhouse gas emissions and energy consumption. This aided in protecting the environment while reducing energy consumption, and achieving a high yield and efficiency of crops at a lower environmental cost.