Research Article
Xingmin Zhao *,Xinxin Guo ,Yiy
Abstract
The significant investigation was performed to establish a chemical baseline for snowfall in Northeast of China since there was no such record. The chemical and mineral composition of snowfall samples were evaluated in Jilin Province, Northeast China. The specific purposes of the present study are to characterize the chemical and mineral composition of melted snow-water samples and to identify the sources of atmospheric pollutants, as well as to investigate the spatial variability of melted snow-water chemistry in this region. Snowfall and aerosol samples were collected from Changchun city, Baicheng city, and Yanji city during November 2015 to March 2016. All the filtered (0.45 m) snow-water was analyzed for conductivity, pH, major cations (Na+, K+, NH4 +, Ca2+, Mg2+) and anions (F−, SO4 2−, Cl−, NO3 -, HCO3 -). The pH of these samples ranged from 6.01 to 7.10, with an average value of 6.44. The conductivity ranged between 17.50 μs cm-1 and 86.00 μs cm-1 with an average value of 55.0 μs cm-1. These parameters indicated high chemical concentrations in the snow-water. It was observed that Ca2+ and NH4 + were the major cations which accounted the concentration for 5.05% to 18.71% and 3.47 to15.54%. HCO3 - and SO4 2- were major anions which accounted the concentration for 23.41% to 38.49% and 21.10% to 35.24%, respectively. (SO4 2- + NO3 -)/ (Ca2+ + NH4 +) was 1.38. The organic carbon of particles in the snowfall was higher and the average content was 52.85 g kg-1. The size of the snow-water particles in the three Cities was mainly based on clay complexes (<2 μm). The order of average content was: (<2 μm)> (>200 μm)> (20-200 μm)> (2-20 μm). The dominant mineral of particles in the snow-water was quartz and feldspar, while clay mineral was composed of montmorillonite, illite, kaolinite and vermiculite. According to the above analyses, the possible sources of the particles in the snowfall should be soil and ground dust and co al-burning.