Ecological Risk Assessment And Spatial Prevention Tactic Of Land Destruction In Large Open-pit Mine

China is rich in coal resources with widely-spreading coal mines, and miningcoal largely destroyed environment; hence, identification of ecological risks in coalmines attracted scholar’s extensive attention. Ecological risks in coal mines aredifferent from those in common area, and cannot be simply identified, so they shouldbe adjusted according to mining’s disturbance. Due to the influence of mineralimmovability and mining production characteristics, mining area ecological system isdamaged and influenced directly or indirectly during the whole period from minesurvey to mine excavation and smelting etc., and the process is complicated.Ecological risks identification processes in coal mines are concluded on the basis ofthe analyses of the influence of coal mining on mine area ecological environment.Typical open-pit mine ecological risk causal chains of Loess Plateau Region areconstructed by means of the analyses of risk source, risk receptor, ecological endpoint identification and exposed-response process.Mining area ecological risk sources are identified and classified from two aspectsof production process of the mining technology and land use type in mine area,including classification methods based on risk of genetic characteristics and landdisturbance types. Reasonable selection and characterization of regional ecologicalrisk source and risk receptor, scientifically discussing and quantifying interactions ofrisk source and risk receptor are the keys of mining area ecological risk assessment.On the process of ATB open-pit mining, the main process of mining area landecological system different kinds of disturbance and destruction are caused by mainmining process from mining to construction of reclamation. Basic ecological risksources are divided into five types including striping, excavation, transportation,dumping and reclamation based on the disturbance types and the intensity differencesof ecological system. Mining area ecological risk receptors are divided into six typesaccording to ecological systems including forestland, grassland, farmland, bare land,rural residential areas and mining area, each type of which is composed of multipleplaques unit.Open-pit mine ecological risk not only has a continuation of the time effect, butalso has a space on the cumulative. Mining disturbances are influenced by thecharacteristics of damaged land and ecological system units, furthermore, relatedclosely to the space distance between them and the adjacent patches properties.Therefore, remote sensing information model and the GIS space analysis model are used to evaluate the sensitivity of land ecological system and land damage cumulativeeffect.Risk comprehensive evaluation is the final phase of mining area risk evaluation.In this phase, the evaluation results of risk resources and their receptors are combinedto evaluate comprehensive ecological risk value of space units in mining area,providing theory basis for ecological risk management in mining area. The ecologicalrisk assessment can be visualized by means of GIS, based on the drawing of themining area comprehensive ecological risk value distribution according to theresearch area of integrated ecological risk value of each unit. The cost for potentialrisk region to recover is estimated from the quantityofmoney of cost for risk,including geological disaster risk cost, coal gangue spontaneous combustion risk costand land degradation risk cost. In the process of open pit mining, the integration of"excavation, striping, transportation, dumping, reclamation" is required and ecologicalrisk prevention is realized in the whole mining area in the process of landformreshaping, soil reconstruction, vegetation restoration, etc., from the basic level ofecological reconstruction preventing the happening of the ecological risk and relapseof habitat.