Study On The Relationship Between Such As Forest Cover As Well As Other Factors And PM_2.5 Based On Panel Data

Most of the domestic and foreign scholars' research on PM2.5 is to study the single factor or multiple factors of PM2.5 in a single city,but few people take multiple cities in a certain area as the research object,which affect Comprehensive analysis of the relationship between multiple factors and determine the main factors affecting PM2.5 concentration.Based on domestic and foreign research,this paper not only innovatively uses 13 cities?districts?in Heilongjiang Province as the research area,but also lags behind forest cover rate,PM2.5 daily average concentration by 1 day,and PM2.5 daily average concentration by 2 Day,PM2.s daily average concentration lags 3 days,PM 10 daily average concentration,SO2 daily average concentration,CO daily average concentration,NO2 daily average concentration,O3₈h daily average concentration,daily average air pressure,daily average relative humidity,daily average light time The number,daily average temperature,and daily average wind speed are jointly used as research indicators,using cluster analysis,path analysis,static panel data model and dynamic panel data model,mainly to explore the forest coverage rate and the time lag effect of PM2.5 and PM2.5 relationship.The main conclusions are as follows:Using big data to establish a scatterplot of daily average PM2.5 concentration in 13 cities?districts?in Heilongjiang Province.The results show that on the one hand,the common change law of 13 cities?districts?in Heilongjiang Province is:the scatterplot is U-shaped;there is almost no pollution during the non-heating period,and there are more days of pollution during the heating period;heating causes the air in Heilongjiang Province The root cause of PM2.5 mass concentration exceeding national environmental protection standards.On the other hand,in areas with high forest coverage,the PM2.5 mass concentration will be correspondingly low;the purification and absorption capacity of forest plants for PM2.5 is limited,and human factors play a decisive role in the process of causing air pollution;forest cover The rate is the most important factor that blocks the increase of PM2.5 mass concentration;meteorological factors have a smaller effect on PM2.5 mass concentration.According to the theory of the static panel data model,a static panel data model is established for each area,and the model is analyzed in conjunction with the path analysis method.The results show that the forest coverage rate has a direct and total effect on PM2.5.The forest Although the overall effect of coverage on PM2.5 is very small,it has the greatest effect on preventing the increase of PM2.5 mass concentration;PM10,SO2,CO,NO2,average pressure,and average relative humidity promote the increase of PM2.5 mass concentration,while O3₈h,The average sunshine time,average temperature,average wind speed,and forest coverage rate hinder the increase of PM2.5 mass concentration.According to the theory of dynamic panel data model,a dynamic panel data model was established for 13 cities?districts?in Heilongjiang Province.In order to ensure that the conclusions obtained were more reliable,this paper established a panel data model for three periods.The results show that:?1?The static panel model and the dynamic panel model in three different time periods are compared and analyzed,and the changes of the time lag effect of PM2.5,the time lag effect of PM2.5 and the forest cover rate are obtained.The changing rules of the factors are consistent,which further proves that the research in this paper is reliable.?2?The time lag effect of PM2.5 is the influencing factor of PM2.5 concentration change;the time lag effect of PM2.5,PM10,and CO all promote the accumulation of PM2.5 concentration in the current period,while the forest coverage,temperature,and wind speed are all Hinder the accumulation of PM2.5;with the passage of time,the promotion effect of PM2.5 time lag effect on the accumulation of PM2.5 concentration gradually weakens,and the hindering effect of forest cover and temperature on the accumulation of PM2.5 concentration gradually increases,The accelerating effect of PM10 and CO on the accumulation of PM2.5 concentration gradually increased,while the hindering effect of wind speed on the accumulation of PM2.5 concentration gradually weakened;while the variation law of the time lag effect of PM2.5 has inertia,the forest coverage rate,PM10,CO,air temperature,and wind speed also have inertial effects on PM2.5.