ORIGINAL ARTICLE Composition of wet deposition in the central Qilian Mountains, China Li Zongjie • Li Zongxing • Wang Tingting • Gao Yan • Cheng Aifang • Guo Xiaoyan • Guo Rui • Jia Bing • Song Yaoxuan • Han Chuntan • W. H. Theakstone Received: 24 January 2014 / Accepted: 17 November 2014 Ó Springer-Verlag Berlin Heidelberg 2014 Abstract A total of 90 individual precipitation samples have been collected in the central Qilian Mountains from August 2012 to November 2013. All samples were ana- lyzed for major cations (Na ? ,K ? , Ca 2? and Mg 2? ), anions (Cl - , NO 3 - and SO 4 2- ) and conductivity. Precipitation EC ranged from 2.26 to 482 lc/cm with an average value of 41.9 ls/cm. Precipitation was of SO 4 2- -Mg 2? -Ca 2? type, and these three ions contributed [ 70 % to the total ionic concentration. Precipitation events occurred around sum- mer displayed lower concentrations, whiles it had higher concentrations in winter and spring with little precipitation and larger wind speed. The major sources for these ions are regional crustal aerosols and species from central Asia and northwestern China arid regions brought by the westerly, and some aerosols from human pollution are secondary sources. It is also interesting that precipitation chemistry is different under diversely atmospheric circulation in Hulu- gou basin: the monsoon precipitation, the interaction pre- cipitation influenced both by monsoon and westerly, and the westerly precipitation events. Keywords China  Precipitation chemistry  Atmospheric circulation  Qilian Mountains Introduction Atmospheric precipitation is an important means of scav- enging pollutants from the atmosphere and this occurs either by wet or by dry deposition (Migliavacca et al. 2005), and so the chemical composition of precipitation or snow/firn is strongly affected by the chemical composition of the atmosphere (Al-Khashman 2005; Kang et al. 2002, 2003, 2004, 2007a, b). Studies on precipitation chemistry are important in evaluating air quality and understanding anthropogenic contributions to atmospheric chemistry/ environment. The change in chemical composition of precipitation can indirectly reflect the atmospheric quality of specific region, which is a particularly sensitive indicator of pollution emissions (Calvo et al. 2010). Knowledge of the chemical composition of precipitation can also provide information of the regional and long-range transport of anthropogenic aerosols and its impact on ecosystems through deposition processes (Mphepya et al. 2004; Li et al. 2007). Precipitation composition can be influenced by many factors, such as local emissions, regional-scale pol- lutants transport processes, meteorological conditions, and sea level elevation (Sickles and Grimn 2003; Calvo et al. 2010; Rocha et al. 2003; Tang et al. 2005; Zhao et al. 2008) and geographical characteristics; elevation difference may influence the chemical composition of rainwater at a par- ticular point in time and in a particular location. Therefore, chemical composition of rainwater varies from site to site and region to region. Moreover, different climate condi- tions also influence trace substance concentrations in the rainwater (Baron and Denning 1993). Numerous studies L. Zongjie College of Forestry, Gansu Agricultural University, Lanzhou 730070, Gansu, China L. Zongxing (&)  W. Tingting  G. Yan  C. Aifang  G. Xiaoyan  G. Rui  J. Bing  S. Yaoxuan  H. Chuntan Key Laboratory of Ecohydrology of Inland River Basin Gansu, Hydrology and Water Resources Engineering Research Center, Cold and Arid Region Environment and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China e-mail: lizxhhs@163.com W. H. Theakstone School of Environment and Development, University of Manchester, Manchester M139PL, UK 123 Environ Earth Sci DOI 10.1007/s12665-014-3907-0