Study On Landscape Ecological Network Pattern Of Open-pit Mining Area Based On GIS

Coal is the main resource of our country.Open-pit mining occupies an important position in China.It has a huge impact on landscape ecology,such as fragmentation of landscape patches and reduction of habitat area of species.At present,as long as the repair of mining areas is concentrated on the improvement of water,soil and vegetation,there are few studies on landscape ecology.This thesis taked Shengli Open-pit Mining Area in Inner Mongolia as an example.According to remote sensing data,spatial analysis method was used to identify ecological sources,ecological corridors and ecological nodes with the support of GIS technology,and to construct ecological network.It was used to connect fragmented patches to promote material flow and information connectivity,thereby enhancing landscape function.The main conclusions were as follows:(1)The suitable landscape pattern index was selected based on the classification of landscape types.The response curve of the patch size of the landscape was constructed,and the accuracy loss was evaluated.The optimal landscape size range of the study area was 30-40 m.The optimal grain size was 30 m combined with the initial resolution of remote sensing image.(2)By analyzing the change of vegetation in the past 30 years,the vegetation improvement area and the high coverage area were extracted as foreground data.Based on the MSPA analysis method,the foreground data was analyzed to extract the core area.In order to highlight the importance of small plaques,the threshold value of landscape connectivity is in the range of 1200-1400 m.According to the landscape connectivity index,the contribution of core areas to the overall landscape connectivity was studied.The top 50 patches with the landscape connectivity index were extracted as the ecological sources.A total of 38 ecological sources were identified,and most of which were distributed along the Xilin River Basin.(3)In this thesis,the minimum cumulative resistance model and hydrological analysis principle were used to identify key ecological areas.The ecological resistance factors were selected.The weight was obtained by spatial principal component analysis,and the landscape resistance surface was obtained by weighting.According to the MCR identification of 77 ecological corridors,using hydrological analysis principles to identify 39 radiation channels.A total of 61 ecological nodes are identified based on the hydrological analysis principle and the circuit theory model.The simulation of low resistance channels with different cost distances based on the ecological resistance surface had guiding significance for the construction of ecological corridors.(4)According to the function,the ecological corridors were divided into species migration corridors,promoting energy exchange corridors between the mining area and the outside of the mining area,town construction corridors,protective forest ecological corridors,etc.;The importance of ecological nodes was analyzed by the integral index of connectivity.14 existing nodes and 47 planning nodes were identified.As the distance from the ecological nodes increases,the ecological resistance of the landscape decreases.In other words,the ecological nodes were in the ecologically weak area with high resistance.After the dump was added as ecological sources,99 ecological corridors and 72 ecological nodes were identified,and the network connectivity index increased.It shows that the integrity and stability of the ecological network have been improved.Restoration of dump increased the possibility of communication of material and information in ecological network.