水稻产量、稻田CH_(4)和N_(2)O排放对长期大气CO_(2)浓度升高的响应  

Response of Yield,CH_(4),and N_(2)O Emissions from Paddy Fields to Long-term Elevated CO_(2) Concentrations

作　　者：于海洋[1,2] 宋开付 黄琼 王天宇 张广斌 马静[1] 朱春梧[1] 徐华[1] YU Hai-yang;SONG Kai-fu;HUANG Qiong;WANG Tian-yu;ZHANG Guang-bin;MA Jing;ZHU Chun-wu;XU Hua(State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室,南京210008 [2]中国科学院大学,北京100049

出　　处：《环境科学》2021年第10期5021-5029,共9页Environmental Science

基　　金：国家重点研发计划项目(2017YFD0300105);国家自然科学基金项目(41877325);中国科学院青年创新促进会项目(2018349)。

摘　　要：大气CO_(2)浓度升高([CO_(2)]e)是全球气候变化的主要驱动力,可直接或间接影响稻田生态系统碳氮循环.深入探究长期(大于10 a)[CO_(2)]e对水稻产量和稻田温室气体排放的影响,对保障粮食安全和评估未来气候变化意义重大.本研究以高、低应答水稻品种为供试材料,利用连续运行14 a的[CO_(2)]升高(free-air CO_(2)enrichment,FACE)平台,共设置2个[CO_(2)]处理:对照(正常[CO_(2)],[CO_(2)]a)和在[CO_(2)]a基础上升高200μmol·mol-1([CO_(2)]e).采用静态透明箱-气相色谱法测定稻田CH_(4)和N_(2)O排放量,并测定水稻产量.结果表明,对比[CO_(2)]a,长期[CO_(2)]e分别增加高、低应答水稻品种产量29%~31%(P<0.05)和12%~14%(P>0.05);分别减少高、低应答水稻品种稻田CH_(4)排放21%~59%和11%~54%;同时,分别显著减少高、低应答水稻品种稻田N_(2)O排放70%(P<0.05)和40%(P<0.05).水稻产量、稻田CH_(4)排放对长、短期[CO_(2)]e的响应具有明显差异,随着[CO_(2)]e年限的增加,水稻产量和稻田CH_(4)排放的增幅显著下降,而稻田N_(2)O排放无明显变化.综合考虑,长期[CO_(2)]e条件下,高应答水稻品种为优先考虑种植的"增产减排"水稻品种.Elevated atmospheric CO_(2)concentrations([CO_(2)]e)are the main driving force of global climate change,which directly and indirectly affect carbon and nitrogen cycling in the paddy ecosystems.Therefore,understanding the response of rice yield and greenhouse gas emissions to long-term(more than 10 years)[CO_(2)]e from paddy fields is of great significance for food security and future climate change assessment.In this study,strongly and weakly responsive cultivars were used as the experimental materials.Based on a free-air CO_(2)enrichment(FACE)platform continuously run for 14 years,two treatments of different[CO_(2)]were set:a control(i.e.,normal[CO_(2)]and[CO_(2)]a)and a 200μmol·mol-1 higher than[CO_(2)]a condition,([CO_(2)]e).CH_(4)and N_(2)O emissions from the rice paddy fields were monitored in situ by static transparent chambergas chromatography,and grain yields were also obtained.The results showed that compared with the[CO_(2)]a treatment,long-term[CO_(2)]e increased grain yields of the strongly and weakly responsive cultivars by 29%-31%(P<0.05)and 12%-14%(P>0.05),and CH_(4)emissions of the strongly and weakly responsive cultivars were reduced by 21%-59%and 11%-54%,respectively.Furthermore,N_(2)O emissions from the strongly and weakly responsive cultivars were significantly reduced by 70%(P<0.05)and40%(P<0.05),respectively.The short-and long-term responses of grain yields and CH_(4)emissions from rice paddy fields to[CO_(2)]e were significantly different.Specifically,with the increase in the duration of[CO_(2)]e,the increases in rice yields and CH_(4)emissions significantly decreased,while the N_(2)O emissions showed no significant changes.Therefore,under long-term[CO_(2)]e conditions,the strongly responsive cultivar has a high potential to reduce greenhouse gas emission and increase grain yields.

关 键 词：CH_(4)排放 N_(2)O排放 稻田 大气CO_(2)浓度升高 高应答水稻品种 低应答水稻品种 产量 

分 类 号：X16[环境科学与工程—环境科学]