山东泗水春季农田地表空气中PM_(2.5)浓度变化及影响因素

Changes in fine particulate matter concentration of near-ground air and its influence on environmental factors at farmlands in Sishui during Spring

在2019年的3月1日-5月31日,以PM_(2.5)采样器、自动气象站与土壤温湿度数据采集器,对山东泗水县开垦农田近地表80 cm处空气中PM_(2.5)逐日浓度与环境因素进行了观测,以回归统计方法分析了PM_(2.5)浓度变化与环境因素的关系。结果显示:在3月-5月,山东泗水县开垦农田近地表80 cm处空气中PM_(2.5)浓度平均值为160.98μg·m^(-3)、变化范围在16.67~333.33μg·m^(-3)。同时,PM_(2.5)浓度变化与风速呈显著指数函数关系(P <0.05),与0-5 cm土层土壤湿度呈显著负相关和指数函数关系(P <0.05);PM_(2.5)浓度变化与气温呈极显著倒数函数关系(P <0.01)。另外,PM_(2.5)浓度变化与风速、气温、相对湿度和0-5 cm土层土壤温湿度因素多元线性回归分析中,风速和土壤湿度影响达到显著水平(P <0.01)。结果表明,在春季,山东泗水县农田近地表空气中PM_(2.5)污染受风速和0-5 cm土层土壤湿度等多种因素影响,会对大气环境产生不可忽视的影响。

The present study observed changes in fine particulate matter(PM_(2.5))concentration and environmental factors of air 80 cm above the ground surface of cultivated farmlands in Sishui County,Shandong Province,China,during spring(March 1 st–May 31 st,2019).PM_(2.5) samplers and automatic weather stations were installed.Soil temperature and moisture data were monitored,and the associations between changes in PM_(2.5) concentration and environmental factors were assessed using regression analysis.From March to May,the average PM_(2.5) concentration was 160.98μg·m^(-3),ranging between 16.67 and 333.33μg·m^(-3).In addition,changes in PM2.5 concentration were exponentially and positively correlated with wind speed(P<0.05),and exponentially but negatively correlated soil moisture in the 0–5 cm layer(P<0.05).Moreover,changes in PM_(2.5) concentration were significantly and inversely correlated with ambient temperature(P<0.01).Furthermore,multiple regression analysis revealed a significant effect of wind speed and soil moisture in the 5 cm layer on PM_(2.5) concentration(P<0.01).These results suggest that in spring,PM2.5 pollution of near-ground air at farmlands in Sishui is significantly affected by wind speed and soil moisture in the 0–5 cm layer,in addition to other factors that have a non-negligible impact on the atmospheric environment.