Drivers of spatio-temporal ecological vulnerability in an arid, coal mining region in Western China

摘要

Ecological integrity of coal mining areas is subject to intense disruption due to the large scale and intensity of operations and the intensification of associated human activity. Negative impacts of coal mining include soil erosion, decline in soil fertility, water pollution, and structural changes to land use. Impacts of coal mining are acute in western China which has been defined as an ecologically fragile zone on account of the arid soils and low rainfall climate that render ecosystem restoration problematic. Here, we studied drivers of ecological vulnerability (EV) in an ecologically fragile area of Shaanxi province and Inner Mongolia that is one of the most globally active and intensive coal mining regions. An evaluation model, using eight indicators of EV such as slope (SL), relief amplitude (RA), rainfall erosion factor (RE), average temperature (AT), land use type (LUT), soil erosion factor (SE), net primary productivity of vegetation (NPP) and coverage of vegetation (CV), was constructed based on a Pressure-State-Response model. An Ecological Vulnerablity Index (EVI) was calculated within the region for 2005, 2010, and 2015 by using the model of EVI and spatio-temporal changes in EV were analyzed. Mechanisms and drivers of EV were assessed using the stepwise regression. The results showed that the area of industrial and mining land increased by 912.96% between 2005 and 2015, where the greatest increase occurred between 2010 and 2015 by 620.00%. The EVI fluctuated insignificantly from 2.69 to 2.78 during the study period and was little related to changes in somewhat areas of urban land use and coal mining intensity. We concluded that the EV of the region slightly increased, despite the extent and intensity of coal mining actives. The main drivers of EV were temperature, precipitation, and land use change. This research will help inform environmental protection policies and environmental planning for coal mining operations in the study area.