Ammonia Emissions May Be Substantially Underestimated in China
Ammonia Emissions May Be Substantially Underestimated in China
复制标题
中国的氨排放量可能被大大低估
DOI：
10.1021/acs.est.7b02171
复制
发表时间：
2017-11-07
影响因子：
11.4
通讯作者：
Gu, Baojing
中科院分区：
文献类型：
--
作者：
Zhang, Xiuming;Wu, Yiyun;Gu, Baojing
中国是全球大气氨排放的热点，其结果是记录了非常高的氮(N)沉积水平。然而，之前对中国NH3总排放量的估计远低于从观测沉降值推断得出的结果，这突显了进一步调查的必要性。在这里，我们基于质量平衡方法重新评估了中国2000年至2015年期间的NH3排放量，并通过N沉降监测和卫星观测进行了验证。中国的NH3排放总量从2000年的12.1+/-0.8tgN年(-1)增加到2015年的15.6+/-0.9tgN年(-1)，年增长率为1.9%，比现有研究结果高出约40%。这一差异主要是由于现在纳入了更多的排放源，以及以前低估了无机肥和畜牧业的NH3排放量。我们估计的NH3排放水平与陆地上NHx(包括NH4+和NH3)的实测值(11-14TgNyr(-1))和卫星观测到的中国上空NH3浓度的大幅增加是一致的。这些发现极大地提高了我们对NH3排放的认识，意味着未来的大气污染控制策略必须考虑中国减少NH3排放的潜力。
China is a global hotspot of atmospheric ammonia (NH3) emissions and, as a consequence, very high nitrogen (N) deposition levels are documented. However, previous estimates of total NH3 emissions in China were much lower than inference from observed deposition values would suggest, highlighting the need for further investigation. Here, we reevaluated NH3 emissions based on a mass balance approach, validated by N deposition monitoring and satellite observations, for China for the period of 2000 to 2015. Total NH3 emissions in China increased from 12.1 +/- 0.8 Tg N yr(-1) in 2000 to 15.6 +/- 0.9 Tg N yr(-1) in 2015 at an annual rate of 1.9%, which is approximately 40% higher than existing studies suggested. This difference is mainly due to more emission sources now having been included and NH3 emission rates from mineral fertilizer application and livestock having been underestimated previously. Our estimated NH3 emission levels are consistent with the measured deposition of NHx (including NH4+ and NH3) on land (11-14 Tg N yr(-1)) and the substantial increases in NH3 concentrations observed by satellite measurements over China. These findings substantially improve our understanding on NH3 emissions, implying that future air pollution control strategies have to consider the potentials of reducing NH3 emission in China.