摘要
全球气候变暖是人类面临的严峻挑战,稻田生态系统在全球气候变暖中起到重要的作用。目前已有许多学者通过大田试验的方法研究了不同秸秆还田方式下温室气体排放的特征,但由于试验地点等因素的不同导致最终的结果差异很大。通过整合这些结果来研究区域内不同秸秆还田方式(翻耕秸秆还田(CTS)、免耕秸秆还田(NTS)和旋耕秸秆还田(RTS))下稻田温室气体排放的特征,能够准确地反映一定区域内稻田生态系统的净减排潜力。本文基于长江中下游地区32篇关于秸秆还田对稻田温室气体排放的文献收集173组数据,利用Meta分析方法研究了3种秸秆还田方式下稻田CH_4和N_2O排放的特征,并估算出不同秸秆还田方式下稻田的全球增温潜势和净增温潜势。结果表明,CTS、NTS和RTS处理下稻田CH_4周年排放的效应值分别为0.76、0.37和0.68,稻田N_2O周年排放的效应值分别为0.44、0.36和0.52;在两熟制下,不同秸秆还田方式下稻田CH_4周年排放的效应值的大小为RTS>CTS>NTS,但N_2O周年排放的效应值的大小为RTS>NTS>CTS。在三熟制下,三种秸秆还田方式下稻田CH_4的周年排放的效应值的高低为CTS>RTS>NTS,而N_2O周年排放的效应值的高低为RTS>NTS>CTS。在相同的秸秆还田方式下,三熟制稻田温室气体周年排放的效应值都高于两熟制。此外,不同的还田秸秆种类影响稻田温室气体的排放;结合前期研究,估算出CTS、NTS和RTS处理下稻田的净增温潜势分别为12 375.55、11 232.36和15 982.87 kg CO_2-equivalent·hm^(-2)。因此,免耕秸秆还田是长江中下流地区稻田净减排条件下适宜的秸秆还田方式。
Global warming is a serious challenge for human beings.Agroecosystems play an important role in the global warming.Many researches have studied the effects of straw returning on greenhouse gas emissions(GHGs) through field experiments,but the results are very different due to many factors such as experiment sites.To merge these results and study the characteristics of greenhouse gas emissions under different straw returning modes(conventional tillage with straw returning(CTS),no tillage with strawing returning(NTS) and rotary tillage with straw returning(RTS)),the net emission reduction potential of paddy field ecosystem in a certain area can be accurately reflected.Based on 32 documents on greenhouse gas emissions in paddy fields in middle and lower reaches of the Yangtze River,this study collected 173 sets of data and conducted a meta-analysis to study the effects of three straw returning modes on CH_4 and N_2O emissions,and estimated global warming potential and net wanning potential in middle and lower reaches of the Yangtze River.The results showed that the effect sizes of CTS,NTS and RTS on annual CH_4 emissions were 0.76,0.37 and 0.68,respectively.While the effect sizes of CTS,NTS and RTS on annual N_2O emissions were 0.44,0.36 and 0.52,respectively.In double cropping system,the effect size of annual CH_4 emission from paddy field was RTS > CTS > NTS,while that of annual N_2O emission was RTS > NTS > CTS.In triple cropping system,the effect size of annual CH_4 emission in paddy field was CTS > RTS > NTS,however,that of annual N_2O emission was RTS > NTS > CTS.The effect size of straw returning on annual GHGs in triple cropping system was higher than that in double cropping system.In addition,the types of straw influenced GHGs from paddy fields.The net warming potential was 12 375.55,11 232.36 and 15 982.87 kg CO_2-equivalent · hm^(-2) under CTS,NTS and RTS,respectively.Therefore,NTS was the suitable straw returning mode for GHGs mitigation in middle and lower reaches of the Yangtze River.
出处
《中国人口·资源与环境》
CSSCI
CSCD
北大核心
2016年第5期91-100,共10页
China Population,Resources and Environment
基金
国家自然科学基金优秀青年科学基金项目"农村土地制度与资源配置"(编号:71322301)
教育部人文社会科学研究青年基金项目"南方稻田不同施肥措施的净减排潜力及推广机制优化研究"(编号:15YJCZH246)
中国博士后科学基金项目"南方稻田不同施肥技术的固碳减排效应及推广调控"(编号:2015M570463)
南京农业大学中央高校基本科研业务费专项资金项目"基于生态经济分析的稻麦秸秆利用机制研究"(编号:SKCX2014001)
关键词
秸秆还田
稻田
温室气体
META分析
长江中下游
straw returning
paddy fields
greenhouse gases
meta-analysis
middle and lower reaches of the Yangtze River
