300 / 2023-10-11 21:04:25

Study on Temporal and Spatial Variation Characteristics of Coal Dust Pollution in the Shengli Mining Area

Google Earth Engine (GEE),coal dust pollution,temporal and spatial change,pixel dichotomy model,linear regression analysis

Abstract: The coal dust produced by open-pit coal mining has a serious impact on the atmosphere, vegetation, soil and living environment in the mining area and its surrounding, but the related research on the degree of coal dust pollution, the quantification of pollution range and the trend of long-term series lags behind. In this paper, the concepts of the maximum influence range and the continuous influence range are put forward. Based on the Google Earth Engine platform and Landsat TM/ETM⁺/OLI images during 2006~2021, the ECDI (Enhanced Coal Dust Index) and the pollution degree of coal dust are inversed. By using linear regression and superposition analysis methods, the time series change and spatial difference characteristics of coal dust pollution in the Shengli mining area are revealed. The results show that: ① The inter-annual variation of coal dust pollution can be divided into severe period (2006~2009), improvement period (2010~2013) and stable period (2014~2021), which shows a trend of first strengthening and then weakening with the advancement of mining time; ② During 2019~2021, the seasonal variation of coal dust pollution showed serious characteristics in spring, followed by summer, autumn and winter, and the difference of seasonal spatial variation is relatively obvious in the relatively harmless area, lightly polluted area and moderately polluted area. ③ The overall accuracy of identifying the influence range of coal dust is 92.67% (kappa coefficient = 0.85). The perennial continuous influence range and the maximum influence range of coal dust continued to shrink with the advancement of mining time, which reached 59.22 km² and 272.20 km² in severe period, 33.91 km² and 54.20 km² late stable period, respectively. During 2019~2021, the spatial and temporal distribution of the annual continuous influence range remained basically stable, while the annual maximum influence range decreased by 15.39 km². ④ During 2006~2021, the relatively harmless area increased by 191.69 km², the seriously polluted area decreased by 4.59 km², the coal dust pollution degree of 52.11% of the mining area showed a downward trend, and that of 4.07% showed an upward trend. As of 2021, relatively harmless area and lightly polluted area accounted for 91.91% of the total area of the mining area (about 601.13km ²). The research results provide theoretical basis and data support for scientific understanding, monitoring and evaluation of ecological conditions in mining areas, and formulation of measures for coal dust prevention and suppression.