长三角区域背景地区SO_2和NO_x本底特征

THE POLLUTANT CHARACTERISTICS OF SO_2 AND NO_x IN YANGTZE RIVER DELTA BACKGROUND REGION

本研究对代表长三角区域背景地区的临安大气本底站2006—2007年的SO2和NOx数据进行分析.结果表明,实验期间,SO2和NOx年均浓度均无明显差异;SO2,NOx季节变化特点和一些城市地区的研究结果一致,都是在冬季浓度较高,夏季浓度较低,不同的是,在邻近临安本底站的上海市,SO2与NO2最高月浓度与最低月浓度的比值小于临安区域本底站SO2与NOx最高月浓度与最低月浓度的比值,说明背景地区污染物浓度更容易受到气象条件变化的影响;SO2和NOx小时浓度日变化和城市地区的双峰双谷型分布形态不同,呈现出单谷型分布形态,午后的14点左右,SO2和NOx小时浓度达到24h中的最低值,SO2和NOx分别在凌晨0点左右和晚上20点左右达到24h中的最大值.

In order to investigate the impact of SO2 and NOx on air quality in the Linan regional air background station which represents Yangtze River delta regional background atmospheric environment, the data of SO2 and NOx during 2006 and 2007 period was discussed. The result showed that （ 1 ） SO2and NOx annual average con- centration in 2006 was not significantly different from that in 2007 ; （2） that concentration of SO2 and NOx was higher in winter and was lower in summer, which was identical with seasonal variation of the concentration of S02 and NOx in urban areas, but the various range of seasonal concentration of SO2 and NOx in background areas was larger than that in urban areas, indicating that weather condition had more obvious effect on pollutant concentration in background areas than in urban areas ; （3） that the single valley distribution of hourly variation of SO2 and NOx concentration in 24 hours in Linan regional background areas, where the minimum of SO2 and NOx appeared at 14：00 and the maximum of SO2 concentration was at 0：00 and maximum of NO, concentration was at 20： 00, was different from double peak and double valley distribution of hourly concentration of SO2 and NOx in 24 hours in urban areas.