| The Ebinur Lake Basin is a region with frequent dust storms and the increase of a wide range of aerosol concentrations has become an important stress factor for the healthy development of the ecological environment in this basin and even in the north slope of Tianshan mountain.The analysis of aerosol spatial-temporal heterogeneity and its influencing factors in this basin is of far-reaching significance for accurately grasping the air pollution situation in Ebinur Lake and adopting corresponding control measures.In this paper,the combination of satellite remote sensing and ground-based remote sensing is used to study the aerosols in this basin,and the spatial and temporal heterogeneity of aerosol optical characteristics in the Ebinur Lake basin is systematically analyzed.Precipitation,soil moisture and wind speed were selected as the main influencing factors,and correlation analysis was carried out from the spatial and temporal scale to evaluate the contribution of each factor to the change of aerosol.Finally,according to the air trajectory,quantitatively simulate the potential source area of aerosol and its contribution degree.The main conclusions are as follows:(1)Spatial distribution of AOD in the last 14 years showed a differentiated "west low,east high" pattern,it is negatively correlated with the terrain.The high value area of AOD is mainly concentrated in Wusu,kuitun and Dushanzi,while the low value areas are mainly distributed in Tori,Bole and Wenquan,and Jinghe and Alashankou are in the transition zone between the low value area and the high value area.The seasonal distribution is similar to the interannual distribution,but there are also some differences.The degree of pollution is in this order: spring、 autumn and summer.The spatial distribution is abnormal in winter due to the large number of vacancy values.(2)In the past 14 years,aerosols in Ebinur lake basin have fluctuated and increased,with a rising range of about 0.03%.The change of AOD value in Ebinur lake basin can be divided into eight stages,namely 4 rising stages and 4 falling stages,but there is no mutation.Analysis of changes during the year shows that high values mainly occur in March,April and June.Among them,the largest aerosol value was appeared in April,and the largest change of aerosol was appeared in June.(3)Comparing and analyzing the spatial differences of aerosol optical properties in typical regions,it is found that the aerosol optical properties of the Jinghe area and the Wusu area are slightly different.The difference is mainly reflected in the following aspects: The atmosphere in Jinghe is cleaner than that in Wusu area.At the same time,the pollution time ratio in Wusu area is greater than that in Jinghe area.By analyzing the relationship between Aerosol optical Depth,Angstrom exponent and second order derivative,it further indicates that fine mode particles are dominant in Jinghe and Wusu regions during the observation period.(4)Precipitation in Ebinur lake basin is negatively correlated with aerosols in spatial scale,and there is a weak negative correlation between summer precipitation and aerosol.Soil moisture is negatively correlated with aerosol,The influence degree of soil moisture on aerosols on the seasonal scale is :summer、 spring and autumn.There was a negative correlation between wind speed and aerosol,and the correlation coefficient was the highest in summer.From the perspective of wind speed,it is found that when the wind speed is small or the wind is calm,atmospheric aerosol is difficult to spread,which aggravates regional pollution.Conversely,when the wind speed is large,the aerosol diffusion ability is strong.According to the multiple regression model,it is found that the multi-factor combination has the most obvious effect on aerosol.(5)Most of the transport tracks in Ebinur lake basin originate from northwest airflow,The potential source regions of the basin aerosol are more concentrated,mainly distributed in the south,northwest and southwest of the basin.The area with high pollution weight is mainly concentrated in the south of Ebinur lake,it is consistent with key source areas of potential source area simulation.These potential sources contribute significantly to the aerosols in Ebinur lake basin. |
