泰安市典型生态功能区空气负离子的时空分布及影响因素分析

Spatial-temporal distribution of negative air ions and its influencing factors in the typical ecological functional zones of Tai'an City

为了探讨城市不同生态功能区空气负离子的时空分布及其影响因素,选取泰安市典型生态功能区(广场公园区、居民住宅区、城市道路区和工业厂房区),对其空气正、负离子浓度、可吸入颗粒物(PM10、PM2.5)浓度及其主要环境因子(空气温度、相对湿度、风速)进行同步监测,系统分析评价了各生态功能区空气负离子动态变化特征,以及与环境因子和可吸入颗粒物的相关性.结果表明:(1)广场公园区空气负离子浓度日变化呈明显的单峰形式,居民住宅区、城市道路区和工业厂房区呈双峰形式,广场公园区的空气负离子浓度最高,其次是居民住宅区和城市道路区,工业厂房区最低;(2)各生态功能区CI指数的平均值大小顺序依次为广场公园区>居民住宅区>城市道路区>工业厂房区;(3)空气负离子日变化浓度趋势与相对湿度变化趋势相似,与温度、空气正离子、风速变化趋势相反.对空气负离子浓度日变化影响较大的环境因子是相对湿度和温度;(4)空气负离子和可吸入颗粒物(PM10、PM2.5)的日变化趋势相反,当空气负离子浓度增大时,可吸入颗粒物浓度减小,空气负离子和可吸入颗粒物呈显著负相关的关系,在相关性上PM10>PM2.5.

In order to explore the spatial-temporal distribution of negative air ions( NAI) and its influencing factors in different ecological function areas of cities. We simultaneously monitored the concentrations of positive and negative ions in air and inhalable particulate( PM10 and PM2.5) and the main environmental factors( air temperature,relative humidity and wind speed) in the typical ecological function areas in Tai’ an city,which included square park area,residential area,urban road area and industrial workshop area,and analyzed the dynamic change of NAI in each ecological function area and their correlations with the environmental factors and inhalable particulate. The results showed that the daily variation of NAI concentration in the square park area was obviously single peak form,while those of the residential area,urban road area and industrial workshop areawere dual peak forms. The NAI concentration in the square park area was the highest,followed by the residential area,urban road area and industrial workshop area. The order of the average value of CI index in each ecological function area was square park area> residential area> urban road area>industrial workshop area. The trend of daily variation of NAI concentration was similar to that of relative humidity,and it was opposite to that of temperature,positive air ions and wind speed. The order of environmental factor for influencing the daily variation of NAI concentration was relative humidity > air temperature > wind speed. The trend of daily variation of NAI concentration was opposite to that of inhalable particulate( PM10,PM2.5). The inhalable particulate concentration decreased with the increase of NAI concentration. The correlation between the NAI concentration and inhalable particulate concentration was significantly negative,and the degree of the correlation was PM10> PM2.5.