安徽省农田生态系统温室气体排放分析及情景模拟

Analysis and scenario simulation of greenhouse gas emissions from farmland ecosystems in Anhui Province

科学认知农田生态系统温室气体排放状况是开展农业减排降碳的重要前提,对于推动农业可持续发展、促进农田高质量建设具有重要意义。以安徽省为例,利用联合国政府间气候变化专门委员会(IPCC)排放系数法评估农田生态系统温室气体排放水平,运用对数平均迪式指数分解(LMDI)方法解析农田生态系统温室气体排放驱动机制,最后基于STIRPAT模型并结合情景分析方法对未来农田生态系统温室气体排放进行模拟预测。结果表明:(1)安徽省农田生态系统温室气体排放总量整体呈增加趋势,水稻种植CH4排放的贡献最大,占比达55.27%,空间分布上呈现为皖中地区排放量较高、皖北和皖南地区相对较低。(2)安徽省农田生态系统单位播种面积排放强度呈增加趋势,单位农业产值排放强度呈下降趋势,两种排放强度均呈“北低南高”分布特征,即淮河以北地区排放强度及变化幅度相对较低,淮河以南地区表现为相反规律。(3)农业经济水平与安徽省农田生态系统温室气体排放呈现出正效应,是影响排放量增加的主要因素;农业生产效率、农业生产结构、农业人口规模均呈现出负效应,其中农业生产效率与农业人口规模因素对农田生态系统温室气体排放的抑制作用较强。(4)基准情景、低碳情景、绿色发展情景与可持续发展情景下农田生态系统温室气体排放呈先上升达到峰值后逐渐降低的变化趋势,其中基准情景在2028年达峰,其余三种情景在2025年实现达峰目标。粗放发展情景下农田生态系统温室气体排放在未来呈不断增加的发展趋势,未能实现达峰目标但增速逐渐放缓,农业发展表现出较强的减排潜力。安徽省应加强控制水稻种植CH4排放,综合考量区域差异,多措并举、因地制宜地制定农业减排政策。

Scientific understanding of greenhouse gas emissions from farmland ecosystems is an essential prerequisite for implementing agricultural emission reduction and carbon reduction measures,and is of significant importance for promoting sustainable agricultural development and facilitating high-quality construction of farmlands.Taking Anhui Province as an example,this study employs the IPCC emission factor method to assess the level of greenhouse gas emissions from farmland ecosystems.The Logarithmic Mean Divisia Index(LMDI)method is used to analyze the driving mechanisms behind these emissions.Finally,based on the STIRPAT model and combined with scenario analysis methods,future emissions from farmland ecosystems are simulated and predicted.The results show that:1)The total greenhouse gas emissions from the farmland ecosystem in Anhui Province are of an overall increasing trend,with CH4 emissions from rice paddies contributing the most,accounting for 55.27%of the total.The spatial distribution shows higher emissions in central Anhui and lower emissions in northern and southern Anhui.2)In Anhui Province,the intensity of emissions per unit sowing area is increasing,while the intensity of emissions per unit of agricultural output value is decreasing.Both types of emission intensity exhibit a“low in the north and high in the south”distribution pattern,meaning that areas in north of the Huai River have relatively lower emission intensity and variation,while areas in south of the Huai River exhibit the opposite trend.3)The level of agricultural economy has a positive effect on the greenhouse gas emissions from the farmland ecosystem in Anhui Province,being the main factor contributing to the increase in emissions;agricultural production efficiency,agricultural production structure,and agricultural population size all show negative effects,with agricultural production efficiency and population size having a stronger inhibitory effect on emissions.4)Under baseline,low-carbon,green development,and sustainable development scenarios,the greenhouse gas emissions from farmland ecosystems show an initial increase to a peak followed by a gradual decrease,with the baseline scenario peaking in 2028 and the other three scenarios achieving their peak targets by 2025.Under the extensive development scenario,the greenhouse gas emissions from farmland ecosystems are projected to increase continuously in the future,failing to achieve the peak target but with a gradually slowing rate of increase,indicating significantly potential for emission reduction in agricultural development.Anhui Province should strengthen control over CH4 emissions from rice cultivation,take into account regional differences,and formulate agricultural emission reduction policies that are multi-faceted and tailored to local conditions.