近10年浙江省城市环境空气质量变化趋势及影响因素分析

摘要

利用浙江省环境空气中SO2、NO2和PM10监测数据,采用Daniel趋势检验法,研究了近10年(2005-2014年)浙江省城市环境空气质量变化趋势及影响因素.结果表明:(1)2005-2014年,浙江省县级以上城市综合污染指数平均值呈显著下降趋势,总体环境空气质量呈好转趋势.(2)SO2年均值呈不显著下降趋势,NO2年均值基本保持稳定,PM10年均值呈显著下降趋势.浙江省SO2、NO2和PM10浓度高值区域主要分布在浙中北部地区,与2005年相比,2014年浓度高值区域面积减少,污染程度降低.(3)SO2、NO2和PM10月均值变化趋势基本一致,浓度高值主要出现在1、11、12月,低值集中出现在6-9月.(4)PM10为城市大气中首要污染物,NO2污染负荷呈显著上升趋势,表明浙江省城市空气污染特征逐渐从煤烟型污染过渡到机动车尾气型污染.(5)产业结构升级、能源结构优化、大气污染物总量减排和污染源综合整治等人为控制措施对城市空气质量改善起到重要作用.地形、气象、沙尘等自然因素是大气污染物浓度时空变化的外因.%According to the urban ambient air quality monitoring data from 2005 to 2014 in Zhejiang Province,the air quality was statistically analyzed in terms of SO2,NO2 and PM10.The variation tread and influence factor of air quality of Zhejiang Province were studied by Daniel trend test method.The results showed that:(1) the average value of comprehensive pollution index in county level cities of Zhejiang Province decreased significantly which suggested the urban ambient air quality presented a trend of improvement during 2005-2014.(2) The annual average of SO2 concentration decreased gradually since 2007.The NO2 concentration basically remained stable.The PM10 concentration showed a significant decline.Spatially,the concentration of air pollutants in the middle and northern Zhejiang was high.The regional area of the high concentration of SO2,NO2 and PM10 decreased and the pollution degree obviously declined in 2014 compared to 2005.(3) The monthly variation of SO2,NO2 and PM10 basically had the same trend.The highest concentration appeared in January,November and December and the lowest concentration occurred from June to September.(4) PM10 was the primary pollutant of urban ambient air pollution.The NO2 pollution load presented a significant upward trend,which showed that the air pollution pattern in Zhejiang Province was transferring from coal burning caused problem to automobile exhaust related pollution.(5) Environmental protection policies such as the upgrading of industrial structure,the improvement of energy efficiency,the total amount control of pollution discharged and the control of pollution source played an important role in improving the air quality.Natural factors such as topography,meteorology and dust storm were external causes of temporal and spatial variations of air pollutants.