Eco-environmental Assessment and Analysis of Tonglvshan Mining area in Daye City, Hubei Province Based on Spatiotemporal methodology

Mine exploitation has a significant impact on the ecological environment status of the surroundings. To analyze the impact of Tonglvshan Mining area to its surroundings, this paper adopted the spatiotemporal methodology based on the extracted Eco-environmental Quality Index ( EQI) to analysis the extent and degree of the effect. The spatiotemporal methodologies are based on two scales: buffers and administrative units. EQI includes Biological Abundance Index ( BAI), Vegetation Index ( VI), Water Network Density Index ( WNDI), and Land Degradation Index ( LDI). The weight of each Index was determined by the analytic hierarchy process ( AHP) and scores of the experts. The calculating of EQI was referenced to the standard "Technical criterion for Eco-environment Status Evaluation" ( HJ/T192-2006) and the "Standards for Classification and Gradation of Soil Erosion" ( SL 190-96). Considering ecological and environmental characteristics relevant to China, this method has been widely used to study the environment status of specific regions in China. The assessment based on buffers adopted the radius of 300m, 500m, 700m, 1000m, 1500m, 2000m, 2500m, 3000m, 3500m, and 4000m as the buffers in 3 typical miners respectively. The calculated result indicates that, the REI is increasing with the radius and the increasing rate becoming smaller until REI is stable. Which means the effect of miner is getting weaker with the distance to the miner is increasing and the effect is diminished when the distance is far enough. The analysis of the 3 typical miner shows that the extent and degree of the effect of miner relates not only with the area of the miner, but also with type of mineral resource, the status of mining and the ecological restoration. The assessment was also carried out by calculating the EQI in 14 administrative units in Daye city in 2000, 2005, and 2010. The study shows that the EQI is decreasing in 14 units from 2000 to 2010. The spatiotemporal analysis of the type and area of land cover in 14 units within ten years period ranging from 2000 to 2010 shows that the mainly factor to affect the eco-environment status is mine exploitation and urban expansion.