Enhanced nitrogen deposition over China
Enhanced nitrogen deposition over China
复制标题
中国上空氮沉降增强
DOI：
10.1038/nature11917
复制
发表时间：
2013-02-28
期刊：
影响因子：
64.8
通讯作者：
Zhang, Fusuo
中科院分区：
文献类型：
--
作者：
Liu, Xuejun;Zhang, Ying;Zhang, Fusuo
中国正在经历严重的空气污染，这在很大程度上是由人为排放的活性氮造成的。这些排放导致大气氮（N）在陆地和水生生态系统中的沉积，对人类和生态系统健康、温室气体平衡和生物多样性产生影响。然而，在中国的氮沉降的规模和环境影响的信息是有限的。在这里，我们使用全国范围内的大量氮沉降，植物叶片氮和作物氮吸收（从长期未施肥的土壤）的数据集，以评估氮沉降动态及其对中国各地的生态系统的影响1980年至2010年。我们发现，在20世纪80年代（每公顷13.2千克氮）和21世纪初（每公顷21.1千克氮）之间，氮的平均年总沉积量增加了约8千克氮（P< 0.001）。中国工业化和农业集约化地区的氮沉降速率与20世纪80年代欧洲西北部的峰值水平一样高，在采取缓解措施之前。来自铵态氮（NH4+）的氮是整体沉积中氮的主要形式，但来自硝酸盐（NO3−）的氮的沉积增加率最大，这与自1980年以来NH3与NOx排放比例的下降一致。我们还发现，氮沉降对中国生态系统的影响，包括显着增加植物叶片氮浓度在自然和半自然（即非农业）生态系统和增加作物氮吸收从长期不施肥的农田。中国和其他经济体面临着减少活性氮排放、氮沉降及其对人类健康和环境的负面影响的持续挑战。
China is experiencing intense air pollution caused in large part by anthropogenic emissions of reactive nitrogen,. These emissions result in the deposition of atmospheric nitrogen (N) in terrestrial and aquatic ecosystems, with implications for human and ecosystem health, greenhouse gas balances and biological diversity,,,. However, information on the magnitude and environmental impact of N deposition in China is limited. Here we use nationwide data sets on bulk N deposition, plant foliar N and crop N uptake (from long-term unfertilized soils) to evaluate N deposition dynamics and their effect on ecosystems across China between 1980 and 2010. We find that the average annual bulk deposition of N increased by approximately 8 kilograms of nitrogen per hectare (P< 0.001) between the 1980s (13.2 kilograms of nitrogen per hectare) and the 2000s (21.1 kilograms of nitrogen per hectare). Nitrogen deposition rates in the industrialized and agriculturally intensified regions of China are as high as the peak levels of deposition in northwestern Europe in the 1980s, before the introduction of mitigation measures,. Nitrogen from ammonium (NH4+) is the dominant form of N in bulk deposition, but the rate of increase is largest for deposition of N from nitrate (NO3−), in agreement with decreased ratios of NH3to NOxemissions since 1980. We also find that the impact of N deposition on Chinese ecosystems includes significantly increased plant foliar N concentrations in natural and semi-natural (that is, non-agricultural) ecosystems and increased crop N uptake from long-term-unfertilized croplands. China and other economies are facing a continuing challenge to reduce emissions of reactive nitrogen, N deposition and their negative effects on human health and the environment.