Atmospheric Nitrogen Deposition at Two Sites in an Arid Environment of Central Asia

• Published in: PloS one Vol. 8; no. 6; p. e67018
• Main Authors: Li, Kaihui, Liu, Xuejun, Song, Wei, Chang, Yunhua, Hu, Yukun, Tian, Changyan
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 26.06.2013; Public Library of Science (PLoS)
• Subjects: Acidification; Air Pollutants - analysis; Air Pollutants - chemistry; Air pollution; Ammonia; Ammonium; Arid environments; Arid regions; Asia; Atmosphere - chemistry; Atmospheric aerosols; Atmospheric chemistry; Biodiversity; Biogeography; Biology; Chemistry; Climate change; Deposition; Droughts; Dry deposition; Earth Sciences; Ecology; Ecosystems; Emissions; Environmental economics; Environmental Monitoring; Environmental pollution; Fluxes; Humidity; Laboratories; Monthly variations; Nitrogen - analysis; Nitrogen - chemistry; Nitrogen cycle; Nitrogen deposition; Nitrogen dioxide; Outdoor air quality; Particle Size; Precipitation; Rain - chemistry; Rainfall; Seasons; Semiarid lands; Semiarid zones; Soil contamination; Wet deposition; Central Asia; Asia; India
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0067018

Arid areas play a significant role in the global nitrogen cycle. Dry and wet deposition of inorganic nitrogen (N) species were monitored at one urban (SDS) and one suburban (TFS) site at Urumqi in a semi-arid region of central Asia. Atmospheric concentrations of NH3, NO2, HNO3, particulate ammonium and nitrate (pNH4 (+) and pNO3 (-)) concentrations and NH4-N and NO3-N concentrations in precipitation showed large monthly variations and averaged 7.1, 26.6, 2.4, 6.6, 2.7 µg N m(-3) and 1.3, 1.0 mg N L(-1) at both SDS and TFS. Nitrogen dry deposition fluxes were 40.7 and 36.0 kg N ha(-1) yr(-1) while wet deposition of N fluxes were 6.0 and 8.8 kg N ha(-1) yr(-1) at SDS and TFS, respectively. Total N deposition averaged 45.8 kg N ha(-1) yr(-1)at both sites. Our results indicate that N dry deposition has been a major part of total N deposition (83.8% on average) in an arid region of central Asia. Such high N deposition implies heavy environmental pollution and an important nutrient resource in arid regions.