乌鲁木齐降水化学成分及来源分析  

Chemical Characteristics and Source Assessment of Atmospheric Precipitation in Urumqi

作　　者：钟玉婷[1,2] 刘新春[1,2] 范子昂[1,2] 陆辉[1,2] 何芳[3] 屈涛 ZHONG Yuting LIU Xinchun FAN Zi＇ang LU Hui HE Fang QU Tao(Institute of Desert Meteorology, CMA, Urumqi 830002, China Key Laboratory of Tree-ring Physical and Chemical Research of China Meteorological Administration/Xinjiang Laboratory of Tree Ring Ecology, Urumqi 830002, China The Operational Department of Xinjiang Meteorological Bureau, Urumqi 830002, China Midong District Meteorological Bureau, Urumqi 831499, China)

机构地区：[1]中国气象局乌鲁木齐沙漠气象研究所,新疆乌鲁木齐830002 [2]中国气象局树木年轮理化研究重点开放实验室/新疆树木年轮生态重点实验室,新疆乌鲁木齐830002 [3]新疆气象局观测与网络处,新疆乌鲁木齐830002 [4]乌鲁木齐市米东区气象局,新疆乌鲁木齐831499

出　　处：《沙漠与绿洲气象》2016年第6期81-87,共7页Desert and Oasis Meteorology

基　　金：国家自然科学基金项目(41405124;41405141)共同资助

摘　　要：降水是大气中主要和次要污染物的重要收集器,是清除大气中颗粒物和气态污染物最好的清除剂。为了了解乌鲁木齐降水特征,本文利用离子色谱分析了2010年降水样品,研究表明,该区降水pH值在5.6~7.77之间,年均值为6.19,电导率变化范围为18.7~172.5μs·cm^(-1),年均值为57.73μs·cm^(-1)。降水中主要离子浓度排序为Ca^(2+)>SO_4^(2-)>NH_4^+>Na^+>Mg^(2+)>Cl^->NO_3^->K^+>F^-,Ca^(2+)是最主要的阳离子,SO2-4是最主要的阴离子,表明乌鲁木齐降水中的致酸物质主要是硫酸盐。总离子浓度季节变化特征表现为秋季高,冬季低。FA平均值为0.001,表明99.9%的降水酸度被碱性成分中和,NF计算结果表明Ca^(2+)具有很强的中和能力。从相关分析、富集因子来看,SO_4^(2-)和NO_3^-主要受人为源的控制,K+主要存在于土壤扬尘或生物质燃烧产生的细颗粒物中;Mg^(2+)主要来自陆源的土壤扬尘等;Cl^-主要来自海相输入,生物质燃烧、人类生活污水排放以及化工厂排放对Cl-也有很大贡献。Precipitation is the important collector of primary and secondary pollutants in the atmosphere, is the best scavenger of the removal of particulate and gaseous pollutants in the atmosphere. To understand the chemical characteristics of precipitation in Urumqi, about 51 precipitation samples were collected in 2010. The pH of samples varied from 5.6 to 7.77 with the average of 6.19, and the conductivity varied from 18.7 to 172.5 μs cm-1 with the average of 57.73 μs cm-1 Ca2＋ is one of the most main cation with the average of 887.43 μeq L-1, while SO42- is one of the most main anion with the average of 430.47 μeq L-1. Acid-causing substance of precipitation in Urumqi is mainly sulfate. The seasonal variations of ions showed that the concentrations were the highest in autumn and the lowest in winter. Fractional acidity （FA） was 0.001, which indicates that 99.9% of the precipitation acidity were neutralized by alkaline composition. Results of neutralization factors （NF） indicated that Ca2＋ was the dominant neutralization substance. The correlation analysis, enrichment factor （EF） and sources indicated that SO42- and N03 were mostly attributed by the anthropogenic activities, K＋ came from soils and biomass burning, Mg2＋ originated from soils and Cl- was mainly contributed by sea sources.

关 键 词：大气降水 乌鲁木齐 离子成分 来源 

分 类 号：P426.612[天文地球—大气科学及气象学]