County-scale N2O emission inventory of China's manure management system

畜禽粪便是我国N2O两个最大排放源之一.为建立我国畜禽粪便N2O高分辨率排放清单,选择2008年县域尺度活动数据、具有空间分异性的本土排放因子和参数来评估其排放规模、组分结构、空间格局及不确定性.与基于IPCC、EDGAR等研究结果相比,该排放清单具有更好的可靠性和全面性.我国畜禽粪便2008年N2O排放总量为572 Gg,其中除了牧场草地粪便之外的畜禽粪便为322 Gg(56.3％),牧场草地畜禽粪便为180 Gg(31.5％),挥发沉降和淋溶径流造成的间接排放分别为45.8 Gg(8.0％)和1.23 Gg(0.2％)；排放格局非常集中,主要分布在东北三省、山东、四川、湖南和河南,其累积规模为全国总量的52.4％,其中近50％贡献源于占全国县域数＜3％的84个县(区、市、旗)；所建立排放清单具有较高的空间分辨率和准确度.与此相比,IPCC对直接排放存在低估,对间接排放存在高估,对排放总量高值区存在低估(-1.5％～-6.0％),低值区存在高估(1.6％～13％)；对于贡献最大的排放途径,EDGAR在高值区低估达到-18.8％-50.0％,在大部分低值区高估达到25％ ～54.1％.Manure is one of the two largest contributors to China's N2O emission. By using the county-scale activity data and the regional emission factors and related parameters with spatial differentiation in China in 2008, this paper assessed the N2O emission loading, sources profile, spatial pattern, and uncertainty, aimed to establish a high-resolution N2O emission inventory of China's manure management system in 2008. As compared with the research results based on the IPCC, EDGAR, and other works, the proposed emission inventory was more reliable and comprehensive. The total China' s N2O emission from manure in 2008 was estimated as 572 Gg, among which, the emission from the manure except pasture/range/paddock was 322 Gg (56.3%), from the manure in pasture/range/paddock was 180 Gg (31.5%), and the indirect emission from atmospheric volatilized N deposition and leaching/runoff was 45.8 Gg (8.0%) and 1.23 Gg (0.2%), respectively. The spatial pattern of China's N2O emission from manure was more centralized, and mainly concentrated in Jilin, Shandong, Sichuan, Hunan, Henan, Heilongjiang, and Liaoning provinces, contributing 52.4% of the total emission, and more than 25% being from 84 counties (only < 3% of the whole counties). The proposed emission inventory had a higher spatial resolution and accuracy. Different with this inventory, the IPCC underestimated the direct emission while overestimated the indirect emission, with the regions of higher emission rate being underestimated by -1.5%-6.0% and those of lower emission rate being overestimated by 1.6%-13%. As for the EDGAR, the regions of higher emission rate were underestimated by -18. 8--50.0%, and those of lower emission rate were mostly overestimated by 25%-54.1%.国家自然科学基金项目PubMed中文核心期刊要目总览(PKU)中国科技核心期刊(ISTIC)中国科学引文数据库(CSCD)0102983-29922