Research On Ecological Security Pattern Construction And Ecological Restoration Potential In Industrial And Mining Town

The industrial and mining towns have made great contributions to the rapid rise of China’s economy and the promotion of the industrialization process.However,due to the lack of overall planning and continuous extensive development of resources,the development of urban construction land and non-construction land is not coordinated,which leads to a series of urban problems such as serious environmental pollution and industrial decline.However,the introduction of the research method of landscape ecological security pattern construction can provide strategies for macroscopically solving the ecological problems of industrial and mining towns and alleviating the dual contradiction between economic development and nature conservation.In this paper,Shuikoushan Town as the research object,first through the field soil sampling and heavy metal content determination,combined with soil pollution evaluation and Kriging interpolation method,to obtain the town soil comprehensive pollution distribution map.On this basis,the use of ecological service value evaluation and habitat quality evaluation method of comprehensive ecological source identification,the comprehensive pollution index of soil and land type,elevation,slope,normalized difference vegetation index,transportation,river town,is apart from the distance,the distance from the mining area,a total of 9 index as evaluation factors,adopt analytic hierarchy process(ahp)to determine the weight of each factor to build the surface Resistance assessment system,the final model with Minimum Cumulative Resistance(Minimum Cumulative hold,MCR),based on the urban and ecological perspective source expansion both competition and cooperation,The minimum cumulative resistance surface and the difference surface of town and ecology were simulated to determine the ecological safety area and buffer zone at high,medium and low levels,identify the ecological corridor,radiation channel and strategic nodes,and construct the ecological security pattern of the town.Furthermore,the potential range of ecological restoration in the existing abandoned industrial and mining areas is further quantified and the restoration time sequence is proposed,and the strategies for the construction of the ecological security pattern of the town and the ecological restoration of the industrial and mining areas are proposed.The results are as follows:(1)The comprehensive pollution index of soil heavy metals showed that the soil in the town was seriously polluted by heavy metals,and few areas were not polluted by the soil.The closer to the smelting plant,the more serious the soil heavy metal pollution is.The characteristics of "point source" pollution are typical.The order of comprehensive pollution index is as follows: the other areas of the exposed mining area > in the south of the smelting area > in the northern factory.(2)Based on the MCR model and hydrological analysis method,14 ecological corridors,167 radiation channels and 54 ecological strategic nodes are agreed upon,which together with three levels of high,medium and low ecological security areas and ecological source areas constitute the ecological security pattern of the town.Area with high levels of ecological security of 773.515 hm squared,8.97% of the total land area,distribution in the southeast region of township,medium level of ecological safety covers an area of 7187.632 hm squared,83.39% of the total land area,wider distribution,low level of ecological safety covers an area of 356.756 hm squared,4.14% of the total land area,mainly distributed in the periphery of the central town construction.(3)In Shuikoushan Town,the area suitable for ecological use is5,603.22 hm~2,and the Ⅰ and Ha-level potential areas are 1605.15 hm~2 and 1488.96 hm~2,respectively,accounting for 28.65% and 26.57% of the total area of eco-suitable reserve potential.The potential area of Ⅲ and the potential area of Fe level are 1343.34 hm~2 and 873.36 hm~2,respectively,accounting for 23.97% and 15.59% of the total area of the ecologically suitable reserve potential,and the potential area of Fe level is 292.41 hm~2,accounting for 5.22% of the total area of the ecologically suitable reserve potential.In the industrial and mining areas,the reserve potential area of the ecologically suitable land is 333.09 hm~2,and the Ⅰand red potential areas are 166.41 hm~2 and 90.9 hm~2,accounting for 49.96%and 27.29% of the total area of the ecologically suitable reserve potential of the industrial and mining areas,respectively.The area of Ⅲ and Quaternary potential areas is 73.98 hm~2 and 1.8 hm~2,accounting for 22.21%and 0.54% of the total area of ecologically suitable reserve potential of industrial and mining areas,respectively.The priority of restoration of the four potential areas is Ⅰ,>,Fe,>,Tuo,>.The key potential areas are concentrated industrial parks such as gold and copper project smelting,Kangjiawan mining area,Shuikoushan non-ferrous metal company,some exposed mining areas and tailings landfill area.The reduction of heavy metals in the soil in the Ⅰ level potential area is the core of ecological remediation.A low-cost and effective green remediation technology,microbial or phytoremediation,can be used to reduce the soil heavy metals through the adsorption,transformation and plant enrichment of microorganisms.The management of water quality in the sub-level potential area is the focus of ecological remediation in this area.Sewage diversion measures and centralized construction of sewage treatment system can be adopted to treat sewage.Vegetation restoration is the key point of regional ecological restoration in Ⅲ and jus potential areas.According to the characteristics of natural environment and open-pit mining area,vegetation restoration is carried out in a comprehensive way.