川东北地区元素大气沉降通量及其季节变化  

Atmospheric Deposition Fluxes and Seasonal Variations of Elements in Northeast of Sichuan,Central China

作　　者：童晓宁[1] 周厚云[1] 游镇烽[2] 汤静[1] 刘厚均 黄颖[1] 贺海波[1] 

机构地区：[1]华南师范大学地理科学学院,广州510631 [2]台湾成功大学地球动力系统中心

出　　处：《环境科学》2014年第1期53-59,共7页Environmental Science

基　　金：国家自然科学基金项目(40973009);广东省高等学校人才引进项目;华南师范大学研究生科研创新基金项目

摘　　要：从2011年8月～2012年7月在川东北地区共收集12个月的大气沉降样品．采用电感耦合等离子体质谱仪（ICP—MS）分析了样品在弱酸性环境下（pH值在2左右）溶解态组分中Na、Mg、Ca、K、Si、Sr、Ba、Zn等元素的含量，计算了这些元素的沉降通量．结果表明：①各元素的沉降通量存在显著的季节变化．Na的沉降通量随着降水增加而显著增加，显示它主要以大气湿沉降为主；Ca、Si、Ba、Sr、Mg的沉降通量在冬季或春季显著上升，显示这些元素的沉降可能主要与大气粉尘活动有关．②不同的元素之间年沉降通量存在显著差异，Na的沉降通量最大，达到30497μg·（10^2cm^2·a）^-1，比最小的Ba沉降通量[27．4μg·（10^2cm^2·a）^-1]高出3个数量级．Monthly atmospheric deposition was collected in Northeast of Sichuan Province from August 2011 to July 2012. Contents of Na, Mg, Ca, K, Si, Sr, Ba and Zn in weak-acid leachable fraction （with pH values of ca. 2） of the deposition were determined using ICP-MS. The results indicated that the deposition fluxes of all these elements exhibited notable seasonal variations. For example, the deposition flux of Na increased with precipitation, suggesting a dominant derivation from wet deposition ; whereas the fluxes of Ca, Ba, Si, Sr and Mg displayed higher values during winter or spring season, suggesting that these elements may be closely associated with atmospheric dust activity. The annual fluxes of these elements were remarkably different in value. Na had the highest flux of 30 497μg·（10^2cm^2·a）^-1, more than three orders of magnitude higher than the lowest flux of Ba of 27.4 μg·（10^2cm^2·a）^-1.

关 键 词：大气沉降 元素 沉降通量 川东北地区 

分 类 号：X131.1[环境科学与工程—环境科学] X169