Study On LFA Evaluation Of Ecological Restoration Models Of Wuhai And Lingwu Disposal(Waste) Fields

The ecological system in the northwest arid desert area is fragile and sensitive.Ecological restoration and evaluation of the mining area in this area is beneficial to coordinate the ecological balance between the mining area and the surrounding environment.At present,China's evaluation methods for the ecological restoration effects of mining areas are still concentrated on traditional methods such as analytic hierarchy process,and lack a systematic evaluation system.Evaluating the structure and function of damaged ecosystems in mining areas at the landscape level has become a research hotspot in recent years.The use of LFA method to evaluate the landscape function of rehabilitated mining area abroad is relatively mature,and has achieved good results in the area of vegetation configuration and management.The application of the LFA method is still in its infancy in China.Existing research has mainly focused on the impact of different vegetation types and mining distances on the landscape function,and the landscape function under different ecological restoration models in the mining area of the arid desert area in the northwest Evaluation studies are still blank.In order to use the LFA method to study the arid desert area in the northwest,evaluate the landscape function effects of ecological restoration in the mining area,and screen for suitable restoration techniques,this study selected the slopes of typical open-pit coal mine dumps and shaft dumps in Wuhai City,Inner Mongolia and Lingwu City,Ningxia as The research object selected a total of 8 ecological restoration models and compared the landscape characteristics of natural shrub-grass communities as restoration targets.Based on the revised LFA evaluation index,by evaluating the patch area index(A1),landscape structure index(A2),soil stability(Sa),soil permeability(If),soil nutrient cycle(Ne)index,the maximum utilization The variance method was used to calculate the weight of each index to obtain the comprehensive evaluation index(Fl)of the landscape function.At the same time,the physical and chemical properties of the soil were measured to analyze the influence of different ecological restoration models and the correlation analysis with the soil performance index obtained by the LFA method was verified.The applicability of the study area and selected the best ecological restoration configuration model in each study area.The results show that:(1)The LFA method has good suitability,can be applied to the study area and can effectively evaluate the landscape function size of ecological restoration in the mining area.The soil stability(Sa),permeability(If),nutrient cycle(Ne)index has a high correlation with the measured soil physical and chemical properties;(2)the combination of biological-engineering technical measures,irrigation-grass structure The vegetation configuration model is better than single biological measures and herbal configuration models in improving the landscape function and soil physical and chemical properties;(3)Wuhai study area,five recovery models can achieve the ecological recovery goals of the dump site,The best restoration effect is the mode of artificial seeding of grass seeds + brick frame lattice slope protection + geotechnical network,and its landscape function(Fl)is the highest,1.3-1.9 times that of other recovery models,and 1.6 times that of the control group;(4)In Lingwu City,the landscape functions of the three restoration models are lower than those of the control group.Although different restoration models have a certain improvement effect on the landscape function of the mining area,the ecological restoration goals have not been reached.In each recovery mode,the landscape function(Fl)of artificially spreading shrub grass + sand barrier is the highest,which is 1.3-2.1 times that of other modes,and the recovery effect of this mode is relatively good.The conclusion of this study provides a theoretical basis and practical experience for the LFA method to evaluate the landscape function restoration effect under different restoration models on the slope of the dumping ground in the northwest arid desert area.It is used to screen the ecological restoration model of the mining area in this area and promote sustainability Provide an important reference for development.