北方典型城市降尘时空分布特征及影响因素分析

Analysis of the temporal-spatial characteristics and affecting factors of dustfall in north typical city

降尘部分反映大气污染情况,是土壤中污染物的主要来源之一,分析其分布特征并探明其影响因素将为区域环境质量改善提供数据支持。文章通过对1997—2006年沈阳市81个大气降尘监测点位数据进行统计分析发现,沈阳市降尘量总体呈下降趋势,月平均降尘量由1997年的23.05t·km-2·month-1下降至2006年的17.36t·km-2·month-1,采暖期降尘量高于非采暖期;沈阳市各城区降尘量大小顺序为:于洪区>沈河区>和平区>大东区>铁西区>东陵区>皇姑区;对比同期环境质量公报与气象数据,推断燃煤和区域气象条件是影响沈阳市降尘的重要内在和外来因素。

Air pollution could be expressed partly by dusffall which is one of the main sources of soil contaminants. Region environmental quality could be improved through studying on the distribution characteristics and affecting factors of dustfall. The statistic analysis of dusffall in Shenyang city was carded out and was based on the data in 81 sample sites during 1997-2006. The results were as follows： The amount of dusffall decreased and the monthly average decreased from 23.05 t·km^-2·month^-1 in 1997 to 17.36 t·km^-2·month^-1 in 2006. The amount of dusffall was higher in heating period than that in non-heating period. The amount of dusffall among these districts of Shenyang was different, and the sequence was Yuhong district〉Shenhe district〉Heping district〉Dadong district〉Tiexi district〉Dongling district〉Huanggu district. The combustion of coal and regional meteorological characteristics were the important factors affecting the dusffall of Shenyang.