KMS Chongqing Institute of Green and Intelligent Technology, CAS
Seasonal fluxes and sources apportionment of dissolved inorganic nitrogen wet deposition at different land-use sites in the Three Gorges reservoir area | |
Cui, Jian1,2,3; Zhang, Yuanzhu4; Yang, Fumo3; Chang, Yajun1,2; Du, Ke5; Chan, Andy6; Yao, Dongrui1,2 | |
2020-04-15 | |
摘要 | To identify seasonal fluxes and sources of dissolved inorganic nitrogen (DIN) wet deposition, concentrations and delta N-15 signatures of nitrate (NO3-) and ammonium (NH4+) in wet precipitation were measured at four typical land-use types in the Three Gorges reservoir (TGR) area of southwest China for a one-year period. Higher DIN fluxes were recorded in spring and summer and their total fluxes (averaged 7.58 kg N ha(-1)) were similar to the critical loads in aquatic ecosystems. Significant differences of precipitation delta N-15 were observed for NH4+-N between town and wetland sites in spring and between urban and rural sites in summer. For NO3--N, significant differences of precipitation delta N-15 were observed between town and rural sites in spring and between urban and town sites in autumn, respectively. Quantitative results of NO3--N sources showed that both biomass burning and coal combustion had higher fluxes at the urban site especially in winter (0.18 +/- 0.09 and 0.19 +/- 0.08 kg N ha(-1)), which were about three times higher than those at the town site. A similar finding was observed for soil emission and vehicle exhausts in winter. On the whole, DIN wet deposition averaged at 12.13 kg N ha(-1) yr(-1) with the urban site as the hotspot (17.50 kg N ha(-1) yr(-1)) and regional NO3--N fluxes had a seasonal pattern with minimum values in winter. The contribution to NO3--N wet deposition from biomass burning was 26.1 +/- 14.1%, which is the second dominant factor lower than coal combustion (26.5 +/- 12.6%) in the TGR area during spring and summer. Hence N emission reduction from biomass burning, coal combustion and vehicle exhausts should be strengthened especially in spring and summer to effectively manage DIN pollution for the sustainable development in TGR area. |
关键词 | Inorganic nitrogen Nitrogen isotope Wet deposition Source apportionment Three Gorges reservoir (TGR) |
DOI | 10.1016/j.ecoenv.2020.110344 |
发表期刊 | ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY |
ISSN | 0147-6513 |
卷号 | 193页码:8 |
通讯作者 | Cui, Jian(jcui@cnbg.net) ; Yao, Dongrui(yaodongrui@cnbg.net) |
收录类别 | SCI |
WOS记录号 | WOS:000521519900028 |
语种 | 英语 |