中国农田的温室气体排放  

GREENHOUSE GAS EMISSIONS FROM CROPLANDS OF CHINA

作　　者：李长生 肖向明 S.Frolking B.Moore Ⅲ W.Salas 邱建军[2] 张宇[3] 庄亚辉[4] 王效科[4] 戴昭华[4] 刘纪远[5] 秦小光[6] 廖柏寒[7] R.Sass 

机构地区：[1]新罕布舍大学地球,海洋与空间研究所,美国Durham,NH 03824 [2]中国农业科学院农业资源和农业区划研究所,北京100081 [3]中国气象科学院农业气象研究所,北京100081 [4]中国科学院生态环境研究中心,北京100085 [5]中国科学院地理科学与资源研究所,北京100101 [6]中国科学院地质与地球物理研究所,北京100029 [7]湖南农业大学农业环境科学学院,长沙410128 [8]莱斯大学生命和进化科学系,美国Houston,Texas 77252-1892

出　　处：《第四纪研究》2003年第5期493-503,共11页Quaternary Sciences

基　　金：美国国家科学基金会 (NSF);环境保护局 (EPA);宇航局 (NASA);中国国家自然科学基金会 (CNSF);中国农业科学研究院 (CAAS)通过陆地生态系统研究计划 (TECO);地球观测系统研究计划 (EOS);CNSF -3 9790 1 0 0

摘　　要：中国是一个农业大国 ,拥有约 1 .33百万平方公里的农田。这些田地的种植、翻耕、施肥、灌溉等管理措施不仅长期改变着农田生态系统中的化学元素循环 ,而且给全球气候变化带来影响。农业生态系统对全球变化的影响主要是通过改变 3种温室气体 ,即二氧化碳(CO2 )、甲烷 (CH4)和氧化亚氮 (N2 O)在土壤 -大气界面的交换而实现的。为了分析多种因素(如气候、土壤质地、农作物品种及各种农田经营管理措施等 )对农业土壤释放CO2 ,CH4和N2 O的综合影响 ,一个生物地球化学过程模型 (DNDC)近年发展起来 ,用于预测这一复杂系统的动态。DNDC模型可对农业生态系统中的碳 (C)、氮 (N)循环进行计算机模拟 ,并计算农田温室气体的释放量。通过与一个地理信息系统数据库的连接 ,DNDC完成了对中国农田 1 990年温室气体排放的估算。结果表明中国农业生态系统的CO2 净排放量约 95百万吨C/年、CH4约 9.2百万吨C/年、N2 O约 1 .3百万吨N/年。根据全球增温潜势 (GWP)计算 ,中国农田释放的N2 O对全球增温的影响高于CO2 和CH4。模拟结果还发现中国农业对减缓全球温室效应的最大贡献发生在 1 980～ 2 0 0 0年间 ,在这 2 0年中 ,全国水稻田的灌溉方法由持续淹灌逐渐改为晒田间灌 ,DNDC计算的中国农田CH4的年排放量由 1 980年的 1 2百?China possesses cropland of 1.33 million km 2. Cultivation of the cropland not only altered the biogeochemical cycles of carbon (C) and nitrogen (N) in the agroecosystems but also affected global climate. The impacts of agroecosystems on global climate attribute to emissions of three greenhouse gases, namely carbon dioxide (CO 2), methane (CH 4) and nitrous oxide (N 2O). Production of the three greenhouse gases in agricultural soils are regulated by many factors (e.g., climate, soil properties, crop type, cropping management etc.). A biogeochemical process model (DNDC) has been developed to predict dynamics of the complex system by integrating the interacting factors. DNDC simulates C and N cycles in agroecosystems as well quantifies fluxes of greenhouse gas emissions from cropland soils. Linked to a GIS databases, DNDC accomplished simulations of greenhouse gas emissions from Chinese croplands in 1990. The results indicated that annual emission rates were 95 Tg C, 9.2 Tg C and 1.3 Tg N for CO 2, CH 4 and N 2O, respectively. Converting the emissions to global warming potentials (GWP), we found N 2O emission dominated the impact of Chinese cropland on global warming. The simulations with DNDC also found Chinese agriculture made a significant contribution to mitigation of global greenhouse gases in the time period of 1980～2000. During the 20 years, the CH 4 emissions from Chinese rice paddies decreased from 12 to 7 Tg per year due to change in water management from continuous flooding to midseason drainage. It has been observed that the increase in atmospheric CH 4 concentration has been slowed down since early 1980s. The modeled decrease in CH 4 emissions from Chinese rice paddies is consistent with the globally observed decrease in the atmospheric CH 4 increase rates in the magnitude and time span. The most effective approach for mitigating CO 2 emissions from the Chinese croplands is to change the current management of the crop residue. Increase in the rate of above ground crop residue incorpora

关 键 词：中国农业 农田 温室气体 生物地球化学 DNDC 地理信息系统数据库 

分 类 号：S181[农业科学—农业基础科学] TP311.131[自动化与计算机技术—计算机软件与理论]