Theory And Methods Of Water And Land Resources Allocation-based Reclamation In Coal Mining Area

The available cultivable land per person was declining year by year in China. Land reclamation in coal mine was an important measure to ensure the cultivable land balance. Based on the summary of the current research and trends of future research on reclamation, the paper studied the reclamation in mining area from the angle of allocation and efficient utilization of water and soil resources.On the basis of the achievements of the existing research, the paper proposed the water and land resources allocation-based reclamation theory and established theoretical framework based on the concepts, meanings and objective conditions.Water and land resources allocation-based reclamation theory emphasized the research on conditions of reclamation area. Based on system theory and resources systems theory, it proposed the "coal mining area - a small watershed " composite system, it established the framework of the coal mining areas eco-environmental system and socio-economic system, it also analyzed the land productivity decline, ecological evolution, terrains and landforms variation, changes in water and land resources in terms of space-time occurrence, etc.Reclamation decision and allocation optimization of water and land resources were the key of the water and land resources allocation-based reclamation. According to the hierarchy feature of coal mining area system, the paper makes water and land resources allocation-based reclamation decisions by AHP method. Therefore, it controlled the water resources in the amount of coal mining areas from a macro-scale to solve the coal mining area within the water more or less in space imbalance by taking small watershed in coal mining area as the background. The land use structure, industrial structure and the availability of water after the coal mining area reclamation had dynamic feature, dynamic programming method ( DP) could be introduced into water and land resources allocation to solve the multi-objective allocation problems under the limited water and land resources. It made a program with comprehensive benefit which conformed to the largest multi-objective water and water resources allocation, and provided a new approach to analyze the coal mining area land reclamation multi-objective water resource balance in theory.Water and land resources allocation-based reclamation highlighted the irrigation system design in reclamation area. Agricultural land reclamation had been the core of coal mine reclamation area in China, the water use in agricultural was the largest. Based on the multi-objective water allocation, the paper introduced the irrigation and crop water relations of production theory and production function model (Jensen model) to establish the crop irrigation system for water-deficient coal mining area, and discussed the pipeline irrigation system planning and design in reclamation area. The empirical research showed that the benefits of pipe irrigation systems on water, land, energy saving, income were obvious.Water and land resources allocation-based reclamation paid attention to the post-evaluation, it considered coordination of the ecological environment and socio-economic development as the ultimate goal of reclamation. On the basis of the systematic theory and method, the paper analyzed the characteristics of ecological environment and socio-economic from the former coal mining area to the reclamation at different stages by introducing the system coupling theory and evaluation methods. According to the specific characteristics of coal mine area systems, it divided the ecological environment and socio-economic evaluation index system, and established the ecological environment and socio-economic indicators of the integrated function model. It analyzed the comprehensive benefits achieved by land and water resources allocation through the ecological environment and the coupling, coupling the coordination degree, comprehensive index of socio-economic system. The evaluation method that coupling ecological environment and socio-economic could systematically evaluate the overall efficiency of reclamation system with comprehensive and operational characteristics. It provided a new pattern for the evaluation of comprehensive benefits of the mining area, and broke the current evaluation method according to new farmland indicator and costing for reclamation.Water and land resources allocation-based reclamation theory was proposed on the achievements of the existing reclamation research. It highlighted comprehensive coordination and optimized configuration of water and land resources in reclamation area by establishing the concept of reclamation system. The next step research should focus on putting the new reclamation theory to promotion and application of ecological restoration and reclamation in coal mining area.