森林覆被率等因子与PM 2.5的时间滞后效应的研究

利用黑龙江省13个市(区)的170820个数据,运用2SLS方法以森林覆被率等11个影响因素为指标,建立了3个不同时间段的静态面板和动态面板回归模型,探究了森林覆被率等影响因素与PM 2.5时间滞后效应的关系。结果表明:①PM 2.5的时间滞后效应是当期PM 2.5浓度积累的影响因素,且随着时间的推移,PM 2.5时间滞后效应对当期PM 2.5浓度积累的促进作用逐渐减弱;②随着PM 2.5时间滞后效应的逐渐减弱,森林覆被率、气温对PM 2.5浓度积累所起的阻碍作用逐渐增强,PM 10、CO对PM 2.5浓度积累的促进作用逐渐增强,而风速对当期PM 2.5浓度积累所起的阻碍作用逐渐减弱;③PM 2.5时间滞后效应呈现出惯性的同时,森林覆被率、PM 10、CO、气温、风速对PM 2.5的作用也具有了惯性。

Relation between Forest Cover Rate and Time Lag of PM2.5

With 170 820 data from 13 cities(districts) in Heilongjiang Province, by using the 2SLS method to take 11 influencing factors such as forest cover as variable, we established three different time periods of static panel and dynamic panel regression models, and discussed the relationship between the lag effect of PM_2.5 and the influencing factors such as forest cover rate. The results show that:①the time lag effect of PM_2.5 is the influencing factor of the PM_2.5 concentration accumulation in the current period, and the promotion effect of the PM_2.5 time lag effect on the PM_2.5 concentration accumulation was gradually weakened with the passage of time. ②With the gradual weakening of the time lag effect of PM_2.5, the forest cover rate and air temperature gradually increased the hindrance of PM_2.5 concentration accumulation, PM₁₀ and CO gradually enhanced the promotion effect of PM_2.5 accumulation, however, the obstacle effect of wind speed increasing PM_2.5 concentration accumulation was gradually weakened. ③While the time lag effect of PM_2.5 showed inertia, the effects of forest cover, PM₁₀, CO, air temperature, and the wind speed on PM_2.5 also had inertia.