中文摘要：

基于县级农业活动水平数据及区域氮循环模型IAP-N方法,并根据地理特征、环境气候条件及地区行政区划将川渝地区划分成4个亚区,详细估算了1990～2004年川渝地区农业生态系统各氨排放源的排放及其时空分布状况.结果表明,1990～1994、1995～1999和2000～2004年3个时期,整个川渝地区农业生态系统氨（NH3）年均排放量（以纯氮量计）分别为626.7、670.5和698.8 Gg·a^-1.氨排放年际变化呈增长趋势,各氨排放源贡献率的年际变化不大,2000～2004年川渝地区施肥农田、粪便管理系统和秸秆燃烧氨排放源的贡献率分别为53%、46%和1%,排放量分别为374.9、318.2和5.6 Gg·a^-1.各地区的氨排放源结构有所不同,成都平原和重庆地区施肥农田氨排放贡献率最高,而川西南地区和川西北地区以粪便管理系统氨排放为主.川渝地区农业生态系统氨排放地理分布总体上呈“东高西低”现象,2000～2004年,重庆丘陵地区、成都平原地区、川西南山地区及川西北高原地区的氨排放量分别为165.6、408.8、85.9和38.8 Gg·a^-1,氨排放强度分别为20、28、9.1和1.6kg.（hm^2·a）^-1.研究结果可为决策者合理利用肥料、减少氨和温室气体排放提供科学依据.

英文摘要：

Ammonia （NH3） emission from agro-ecosystem in the Sichuan-Chongqing region during 1990-2004, was estimated by the regional nitrogen cycling model IAP-N. The county level agricultural activities data were used, and Sichuan-Chongqing region was divided into four subareas by the geographical characteristics , environment and local climatic conditions and administrative division. The results showed that average annual ammonia emissions （in nitrogen gauge） in 1990-1994, 1995-1999, 2000-2004 were 626.7, 670.5 and 698.8 Gg.a^-1 respectively. The ammonia emission appeared increasing trend, whereas, the contribution of various ammonia sources presented little change. For instance, in 2000-2004, the contributions of NH3 emission from fertilized cropland, manure management system and field residues burning to the total ammonia emission of agro-eeosystem in the Sichuan-Chongqing region were 53%, 46% and 1%, equals to 374.9,318.2 and 5.6 Gg.a^-1 respectively. But the contributions were variable in different regions. Ammonia emission was primarily induced by fertilized cropland in Chengdu plain and Chongqing hilly area, whereas, in northwest sub-region of Sichuan province was manure management system. The geographical distribution of ammonia emission from agro-eeosystem in the Sichuan-Chongqing region was generally ＂east high and west low＂. Ammonia emissions in sub-regions of Chongqing hilly area, Chengdu plain, southwest and northwest sub-regions were 165.6, 408.8, 85.9 and 38.8 Gg.a^- 1 , respectively, during 2000-2004. At the same time, ammonia density were 20 and 28 kg＂ （hm^2.a）^-1 in sub-regions of the Chongqing hilly area and the Chengdu plain, whereas, 9.1 and 1.6 kg.（hm^2.a）^- 1 in southwest and northwest sub-regions, respectively. The results will provide a scientific basis for making fertilizer effectively applied and mitigate NH3 and GHG emissions from agro-eeosystem of Sichuan- Chongqiug region.