Synthetic Evaluation Of Ecological Environment Influence, Ecological Environmental Protection And Ecology Repair Countermeasures For Open-pit Mining

The mine selection industry is the national economy basic industry, the mineral resource exploitation activities have brought the huge negative influence for the ecological environment, particularly the open-pit mining, is serious to the surface soil's stripping and natural vegetation's destruction, therefore, studying eco-environmental impact assessment on development strip mining's and selecting the ecological protection and restoration measures have the vital practical significance.This article that based on the comprehensive analysis of present researches of domestic and international open-pit mining environment impact assessment, ecological environment protection and ecological restoration, takes the ecological environmental protection and the ecology repair theories as a foundation, unifies the domestic and foreign open-pit ecological environmental protection and the ecology repair practice, takes the open-air gold mining in Xinjiang as the study object, has established the synthetic evaluation indicator system of ecological environment influence for open-pit mining, and has proposed the corresponding countermeasures about open-pit mining ecological environmental protection and the ecology repair. The main achievement of the research includes:(1) This article has established the synthetic evaluation indicator system of ecological environment influence for open-pit mining, including the target layer, the criterion layer and the index layer. The target layer is the ecological environment influence quality synthetic evaluation target; the criterion layer includes the soil degradation, the vegetation degree of coverage, the biodiversity, the water resources, the ecology landscape, the environment quality; the index layer is composed of 21 secondary indicators.(2) According to the characteristics of the ecological environment, this article has determined the evaluating indicator system's weight, the computation and the assessment method, has used the analytic hierarchy process (AHP) to determine the weight of each index, has quantified and standardized indexes by using the percentage of indicators standardized method and has carried on the computation using the linear synthesis method.(3) Using synthetic evaluation indicator system of ecological environment influence for open-pit mining, this article takes a comprehensive assessment of eco-environmental impact to some open-air gold mining in Xinjiang. The results shows that: the value of eco-environment index (EIa) is 0.4033, which belongs to the general level; The value of eco-environment prediction index (Elb) is 0.3637, which belongs to the general level, too:the change range (â–³EI) is between 0.02 to 0.05. which belongs to the slight change, all of these demonstrates that mining has influence to the ecological environment.(4) According to the results of eco-environment quality, environmental impact prediction and evaluation, this article provides some ecological and environmental protection measures for open-pit mining:such as site select and alternative scheme, wild animals and plants protect measures and conservation measures of water and soil. Through these ecological protection measures, it can make the ecological system not to change significantly; biomass does not decrease obviously; the wild animal habitat is not affected obviously.(5) By studying the optimal conditions of ecological restoration. this article proposes the ecology repair measure, including land reclamation technical measure and side slope ecology-repair technical measure. Land reclamation technology includes surface humus soil stripping and piling, blocks the dregs dam. retaining dam, flood drainage guide, land leveling and backfilling of soil humus. Side slope ecology repair technical measures includes vegetation bag method, vegetation net method, soil spraying attached, hydraulic seeding method and the thick layer of substrate method. Through the ecology repair measure, it may slow down the open-pit mining effectively to the ecological environment influence availably.