Changes of landscape ecological quality for land reclamation in mining area

Abstract: With the rapid exploitation of coal resources, a series of ecological and environmental problems, such as surface subsidence, stagnant water, and soil pollution, etc., became increasingly serious. How to strengthen ecological environment protection by reasonable and efficient ways becomes one of the key issues of the sustainable development of mining area. The projects of land reclamation and ecological restoration are the correct and effective measure for improving the ecological environment of mining area. In order to research the effects of land reclamation on the changes of landscape ecological conditions in mining area, taking Jiawang mining area in Xuzhou as example, the landscape ecological quality and its changes were evaluated using the evaluation model, which was constructed at the stability and disturbance level of land ecosystem based on the means of remote sensing, GIS and landscape ecology. The indicators of ecological stability include vegetation cover index, biological abundance index, land use structure index, landscape diversity index and rivers density index, and the indicators of ecological disturbance contain landscape fragment index, construction land disturbance degree index, landscape advantage degree index and land deterioration index. The weight of each indicator was defined by the analytical hierarchy process method (AHP). Landscape ecological quality index can be expressed as landscape stability index divided by landscape disturbance index, which can evaluate the conditions of landscape ecosystem. With the index value greater than 1, the landscape ecological quality is high and the landscape ecosystem is steady. The greater the index value is, the better the ecological quality is, vice versa, the landscape ecological quality is low. The results show that landscape ecological quality of Jiawang mining area has changed significantly and the general trend was better. The stable and more stable area in 2001 and 2010 were 49994.86 hm2 and 56160.31 hm2 respectively, and was increased by 6164.45 hm2 from 2001 to 2010. From the overall changes, the area of good and slightly good changes focused on less-destruction mountain area and coal mine reclamation district took up 28.33%, which indicates that the mining land reclamation project has played certain improvement on the regional ecological environment. However, the region of bad and slightly bad changes took up 19.44%, which implies the ecological environment quality in some areas still declined due to the rapid urban growth, accelerated speed of mining, not timely environmental protection, secondary collapse, and low governance standards, etc. It is therefore necessary to strengthen the protection of ecological fragile areas, perfect technical regulation for mine reclamation and establish ecological restoration strategy to achieve the sustainable development of mining area.