上海市大气环境中PM2.5与其他污染物相关性研究

为研究上海市不同地区的PM_(2.5)污染水平,选取徐汇上师大(市区)和浦东川沙(郊区)两个监测点的PM_(2.5)为研究对象,分析其变化特征及与空气中的PM_(10),CO,NO_2,SO_2和O_3间的相关性.结果表明:(1)PM_(2.5)与PM_(10)由于存在形态和成因相似而具有很强的相关性;(2)在季节分布上,夏秋季颗粒物浓度低,冬春两季颗粒物浓度高,春季颗粒物浓度低于冬季.PM_(2.5)与PM_(10)在不同季节表现不同,颗粒物的粒径分布特征在一定程度上与监测点周边的污染源及气象因素有关.(3)市区和郊区的PM_(2.5)和PM_(10)浓度都呈双峰性变化,PM_(2.5)与PM_(10)日变化存在相似性.(4)通过逐步回归建立PM_(2.5)的回归模型,结果表明空气中的PM_(2.5)浓度的变化会受到其他污染物的共同作用,不同区域对PM_(2.5)浓度变化贡献大的污染物也有不同.

Correlations of PM2.5 with Other Pollutants in the Atmosphere of Shanghai

In order to investigate the pollution level of PM_2.5 in different areas of Shanghai, Shanghai Normal University at Xuhui District (an urban area) and Chuansha Town at Pudong New Area (a suburban area) were chosen as the study areas to analyze the characteristics of PM_2.5 and the correlation of PM_2.5 with PM₁₀, CO, NO₂, SO₂ and O₃. A significant correlation was shown to exist between PM_2.5 and PM10 due to their similarities in shape and origin. In the seasonal distribution, the concentration of the particulates was lower in summer and autumn than in winter and spring. PM_2.5/PM10 had different behaviors in different seasons, and the size distribution characteristics of the particulates were related to the pollution sources and meteorological factors around the monitoring stations. The concentrations of PM_2.5 and PM10 in the urban and the suburban areas showed a bimodal change and PM_2.5/PM10 showed a similar pattern in its daily change. A regression model of PM_2.5 was established by stepwise regression, and the results showed that the change of PM_2.5 concentration was co-affected by other pollutants. The pollutants which were the major contributors to PM_2.5 concentration were different in different areas of Shanghai.