Characteristics of Atmospheric Reactive Nitrogen Deposition in Nyingchi City

作者：Wei Wang, Wen Xu, Zhang Wen, Dandan Wang, Sen Wang, Zhiwei Zhang, Yuanhong Zhao, Xuejun Liu · 发表于：Scientific Reports · 年份：2019 · DOI：10.1038/s41598-019-39855-2 · 被引用次数：38 · 研究领域：Atmospheric chemistry and aerosols、Plant responses to elevated CO2、Atmospheric and Environmental Gas Dynamics

Abstract Atmospheric reactive nitrogen (N) deposition has been proven to be an important nutrient input from external environments to forest ecosystems. However, the magnitude of atmospheric N deposition in the Tibetan region of China is not well known. In this study, multi-year (between 2005 and 2016) measurements of dry and wet N deposition were carried out in Nyingchi (NC) city, southeastern Tibet. Bulk deposition was collected by the rain gauge method; dry deposition was calculated by the inferential method, namely, multiplying ambient N concentrations by dry deposition velocity (V d ) of the N species. During the entire period, annual bulk and dry N deposition fluxes averaged 2.19 and 1.85 kg N ha −1 yr −1 , respectively. Total N deposition fluxes (the sum of reduced and oxidized N species in dry and bulk deposition) showed an obvious increasing trend, especially for oxidized N species. Both bulk and dry N deposition showed a consistent seasonal pattern, with the highest fluxes in summer and the lowest in winter. Our findings suggest that N deposition to the urban environment in southeast Tibet has recently shifted from ammonium-dominated to nitrate-dominated conditions.