title: Atmospheric Nitrogen Deposition at Two Sites in an Arid Environment of Central Asia.
abstract: 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.
authors.affiliation: Key Laboratory of Biogeography and Bioresource in Arid Land, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.
authors.forename: Kaihui
authors.initials: K
authors.lastname: Li
authors.forename: Xuejun
authors.initials: X
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Song
authors.forename: Yunhua
authors.initials: Y
authors.lastname: Chang
authors.forename: Yukun
authors.initials: Y
authors.lastname: Hu
authors.forename: Changyan
authors.initials: C
authors.lastname: Tian
mesh_terms: D000393:Air Pollutants / Q000032:analysis* / Q000737:chemistry*; D001208:Asia; D001272:Atmosphere / Q000737:chemistry*; D055864:Droughts; D004784:Environmental Monitoring; D009584:Nitrogen / Q000032:analysis* / Q000737:chemistry*; D010316:Particle Size; D011891:Rain / Q000737:chemistry; D012621:Seasons
chemical_list: D000393:Air Pollutants; D009584:Nitrogen