Atmospheric reactive nitrogen concentrations at ten sites with contrasting land use in an arid region of central Asia
- 1State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
- 2Graduate University of Chinese Academy of Science, Beijing 100039, China
- 3College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
- 4Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China
- 5College of Grassland and Environmental Sciences, Xinjiang Agricultural University, Urumqi 830052, China
- 6Cele National Station of Observation and Research for Desert-Grassland Ecosystems in Xinjiang, Cele 848300, China
- 7Agri-Environment Branch, Agri-Food and Biosciences Institute, Belfast BT9 5PX, UK
- *These authors contributed equally to this work.
Abstract. Atmospheric concentrations of reactive nitrogen (Nr) species from 2009 to 2011 are reported for ten sites in Xinjiang, China, an arid region of central Asia. Concentrations of NH3, NO2, particulate ammonium and nitrate (pNH4+ and pNO3−) showed large spatial and seasonal variation and averaged 7.71, 9.68, 1.81 and 1.13 μg N m−3, and PM10 concentrations averaged 249.2 μg m−3 across all sites. Lower NH3 concentrations and higher NO2, pNH4+ and pNO3− concentrations were found in winter, reflecting serious air pollution due to domestic heating in winter and other anthropogenic sources such as increased emissions from motor traffic and industry. The increasing order of total concentrations of Nr species was alpine grassland; desert, desert-oasis ecotone; desert in an oasis; farmland; suburban and urban ecosystems. Lower ratios of secondary particles (NH4+ and NO3−) were found in the desert and desert-oasis ecotone, while urban and suburban areas had higher ratios, which implied that anthropogenic activities have greatly influenced local air quality and must be controlled.