Atmospheric reactive nitrogen concentrations at ten sites with contrasting land use in an arid region of Central Asia.

Atmospheric concentrations of reactive nitrogen species (Nr) from 2009 to 2011 are reported for ten sites in Xinjiang, an arid region in Northwest China. Concentrations of NH , NO , particulate ammonium and nitrate (pNH Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. and pNO Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. ) showed large spatial and seasonal variation and averaged 7.71, 9.68, 1.81 and 1.13 µgNm^-3 , and PM₁₀ concentrations averaged 249.2 µgm^-3 across all sites. Lower NH₃ concentrations and higher NO , pNH Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. and pNO Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. 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 order of increasing 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 (NH Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. and NO Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. ) were found in the desert and desert-oasis ecotone, while urban and suburban areas had higher ratios, which implies that anthropogenic activities have greatly influenced local air quality and must be controlled. [ABSTRACT FROM AUTHOR]