Study On Land Reclamation Of Daliu Coal Mine In Xuzhou

The problem of resources and environment is an important factor that restricts the sustainable development of China's economy and society.As one of the most important resources,the waste of land resource and the following damage of ecological environment caused by coal mining are the outstanding manifestation of the contradiction between man and land.Attention to these problems in the development and utilization of mineral resources calls for study of land reclamation.Land reclamation in coal mine area not only affects the balance of land use,but also is of vital importance for cultivated land protection and sustainable land use.It is also a powerful exploration for the scientific implementation of mineral exploitation and sustainable land use.It is of great significance for the construction of a resource-saving society and the promotion of sustainable economic development.Taking Daliu coal mine area of Xuzhou as a research area,this study analyzes the process and mechanism of land reclamation in the mining area.AHP is used to evaluate the suitability of each alternative plan of land reclamation,namely the schemes of land reclamation for agricultural land,constructive land and ecological land after mining.According to the evaluation results,aiming at the three subsystems of economy,society and ecology,combined with qualitative analysis and quantitative estimation,the benefits of land reclamation are calculated,in order to provide reference for the future land reclamation in small coal mine areas.The research conclusions are as follows:(1)The analysis of the current land use shows that cultivated land and commercial land constitute the main types of land use in the region.Land damage turns to be slight ground collapse.Mining activities have brought certain damage and pollution to land resources,water resources and biological resources.The land use classification system in the study area is divided into six types,agricultural land,constructive land,traffic land,water area,subsidence area,and other land.The data sources of ETM remote sensing images include website of Geospatial data cloud,Google maps,and national platform for common geospatial information services.The analysis mainly includes the degree of land use,the rate of land use change,and the land use transfer matrix.From2004 to 2020,the land reclamation rate of mining areas has decreased from 55.38%to 26.42%,the utilization rate of land agriculture has decreased from 60.69%to 37.12%,and the utilization rate of land construction has increased from 19.33%to 34.72%.The comprehensive dynamic degree of land use change from 2004 to 2020 is the largest,which is 2.36 percentage points,indicating that land use change during this period is relatively significant.From 2012 to 2020,land use types have undergone a transition from a rapid trend to a slight one,and the transfer mainly occur among subsided land,agricultural land and construction land.(2)With regard to the suitability evaluation of land reclamation in mining area,it is proposed to select three criteria level elements including suitability,driving factors and restricting factors,as well as 10 sub criteria level elements of natural endowment,location traffic,population factors,economic factors,public will,environmental assessment,landscape structure,benefit indicators,interference degree and risk factors for index system.Specific index systems for three reclamation directions,thus agricultural land,construction land,and ecological land,are construct respectively.The weight is determined by AHP,and the decision process model of AHP is constructed,calculated and analyzed by Yaahp12.4.For the lack of data scored by experts,the incomplete matrix is completed.After calculating the weight of each factor,the weighted score is calculated with the score obtained through grading,and the weighted score is obtained as the reference of the evaluation result.According to the evaluation results,the suitability evaluation score of land reclamation for agricultural use in the mining subsidence area of Daliu coal mine is77.98,the score of land reclamation for construction is 66.73,and the score of land reclamation for ecological use is 62.03.After the reclamation treatment,the original mining land of 47.51 hm~2is expected to convert into agricultural use.(3)The system dynamics model is used to determine the causal relationship between reclamation measures and reclamation benefits to form a dynamic system of reclamation benefits.Based on the theory of ecosystem service function,the static and dynamic quantitative estimation of land reclamation benefits is made.In consideration of soil fertility recovery,we divide the period of land reclamation to the initial,middle and late stage,taking the year 2023 as boundary.Consequently,the period from 2021 to 2023 is the initial stage of land reclamation,and the period from 2023 to 2028 is the middle and late stage of land reclamation.The quantitative estimation results show that after the land reclamation,the subsided land of Daliu coal mine is supposed to convert to agricultural land.The economic benefits generated by the production function in the initial,middle and late stages of reclamation are 106626.5 yuan,284337.3yuan and 426506 yuan.After the newly cultivated land is put into agricultural production,the agricultural products will enter the circulation and sale,and the annual economic effect may be121868.8 yuan.Accordingly,the social effect from microcosmic to macroscopic will be produced.In the early,middle and late stages of reclamation,the land reclamation benefits will be 25751.22yuan,68669.91 yuan and103001.9 yuan,respectively.The educational benefit of land reclamation is 2.2801 million yuan per year.The annual ecological service value of reclamation is about 205900.8yuan in the initial stage of reclamation,and the ecological benefit in the middle and late stage of reclamation is317084.02 yuan to 475626.03yuan.Land reclamation is proved to be of vital importance through our research in Daliu coal mine area,and there are benefits brought by restoration.We hope that this paper can provide theoretical support and data support for ecological restoration in mining area,and the land reclamation of small mining areas.