乌鲁木齐大气污染现状及影响因素分析

对乌鲁木齐市1999-2008年空气污染物监测数据分析表明,乌鲁木齐主要污染物中可吸入颗粒物(PM10)、SO2和NO2,其浓度均表现为采暖期大于非采暖期,采暖期日平均PM10值为国家二级标准日平均浓度的1.74倍,SO2为1.45倍,NO2最低,且采暖期与非采暖期均处于达标状态。污染最严重的季节是冬季,重度污染天气1月最多为7.5 d,其次为12月5.3 d。城区南部污染重于北部和中部。乌鲁木齐大气污染的原因,主要有地形因素造成冬季风速小、温度低、逆温层厚、空气稳定性强。冬季漫长,供暖、供热、供电系统耗能多,排放污染物数量大,城市布局不合理,供暖、供热、供电系统距城市中心太近、城市中心区域人口密度大、交通拥挤污染程度重。

Analysis on Current Status of Atmospheric Pollution and Its Affecting Factors inUrumqi

An analysis of the levels of air pollution in Urumqi shows that there were three kinds of inhalable particles in the main pollutant in Urumqi：PM10,SO2 and NO2,whose density showed heating period〉non-heating periods.PM10 of heating period,surpassing the set standard was 1.74 times,standard of SO2 was 1.45 times,but NO2 was the lowest which reached the standard during heating period and non-heating period.The winter was the most seriously polluted season.The most seriously polluted weather accounted for 7.5 days of Jan.and 5.3 days of Oct..The pollution index in south part of Urumqi was higher than that of north part of it.The pollution in atmosphere of Urumqi were mainly caused by topographical factors such as low wind velocity in winter,thick inversion layer,strong stabilization of atmosphere.The atmospheric pollution caused by a great amount of power supply,heating supply,heat supply in long winter.A great amount of pollutant were discharged from Urumqi.The system of heating supply,heat supply,power supply were too close to the center of Urumqi city and there were a great population density in the center of city.