Vegetation changes in coal mining areas: Naturally or anthropogenically Driven?

Abstract

Vegetation fractional coverage is an important indicator for the ecological environment quality in the mining area. The relationship between vegetation fractional coverage and topographical and climatic factors has been studied intensively. However, in coal mining areas, anthropogenic factors are closely linked to vegetation cover for the frequent production activities, and should be accounted into the driving factors. In this study, we analyzed the spatio-temporal changes of vegetation fractional coverage in Yangquan Mining Area, China. To explore the dominant factors affecting vegetation fractional coverage, geographical weighted regression models combining four natural factors (temperature [T], precipitation [P], elevation [DEM], and slope [Slope]), two anthropogenic factors (population density [Pop] and GDP density [GDP]), three distance factors (distance from roads [D-road], towns [D-town] and water sources [D-water]) were established. We analyzed the model results of four periods (2000, 2005, 2010, 2015) in three parts (exploited area, unexploited area, Yangquan Mining Area overall), respectively. The results indicated that the vegetation fractional coverage demonstrated an overall increasing trend. The vegetation fractional coverage was higher in the unexploited than that in the exploited areas, and the differences increased over time. The impact intensity of nine factors in descending order was Pop > GDP > P > T > D-road > D-town > DEM > D-water > Slope. T, P, DEM, D-road, and D-town were positive factors, whereas Pop and GDP were negative factors. Between 2000 and 2010, the vegetation fractional coverage trends were mainly influenced by anthropogenic factors, whereas in 2015, natural factors exceeded anthropogenic factors as the dominant factors. Present study concluded that anthropogenic factors had a non-negligible negative impact on vegetation cover in mining areas. However, the impact of anthropogenic factors on vegetation presented a decreasing trend. Natural factors have exceeded anthropogenic factors as the dominant factors in recent years. This study provides a theoretical support for future ecological protection and restoration in the Yangquan Mining Area.