Analysis On Optimal Allocation Of Land And Water Resources In Different Hydrological Situations In Hebei Province

In this paper,Arc GIS software is used to establish hydrological models based on different hydrological years to simulate the spatial distribution characteristics of water resources in the study area under different hydrological scenarios.Through a series of algorithms,the water availability of spatial units in the county(city)area is determined.Then using the quota analysis method to calculate the water demand of different land types,through the establishment of multiple scenarios of water and soil resources balance matching index to determine the spatial coupling interaction between water and land resources,revealing the main factors that lead to the spatial structure of water and land resources in the study area mismatch.According to the interaction coefficient of water resources,taking water resources as the main constraint,the multi-objective linear programming model was used to optimize the spatial distribution of land use structure in the study area.Provide theoretical basis for the sustainable use of land and water resources and land planning and revision.(1)According to the years of hydrological and meteorological observations of different spatial units in the study area,SPSS software was used to perform Mann-Kendall trend test on the relevant data to determine three different hydrological years of Rich water year,Flat water year and Dry year.(2)By setting different hydrological years,using the SWAT model to simulate the regional water resources under different land use change scenarios,the spatial distribution law of water resources in the study area was clarified.Calculate the available water quantity by establishing a calculation model,refer to the socio-economic data of the study area and the inter-basin water transfer situation,and obtain the water availability of the spatial unit in the county(city)area.(3)According to the law of water demand of different types of land use,the use of quota analysis method to calculate the demand for water resources by different types of land use.By establishing a coupling interaction index model of land and water resources,the interactive equilibrium relationship between water and land resources was analyzed to clarify the impact of land use changes in different hydrological years on the regional water and soil resources balance relationship.(4)Using the principle of linear programming,under the constraints of water resources,a multi-objective planning model for the coupling of land and water resources was established to determine the optimal structure of land use types in cultivated land,construction land,forest land,grassland,water areas,and other unused land in the study area.On this basis,the spatial and spatial optimization of water and land resources under different hydrological scenarios is performed for the county(city)domain units in the study area to provide a practical and feasible solution for the coupling control of water and land resources.(5)When the hydrological scenario is the dry year and the peace year,the coupling of the soil and water resources in the study area is low.According to the research results,the type of cultivated land with the largest water consumption should be reduced.The total nuclear reduction area of Hebei Province is 15796.82km~2 and 4917.53km~2,respectively.The spatial distribution map of arable land in each county(city)area was reduced,and the central area with the largest nuclear reduction area was the central plain.During the flood season,small-area adjustments can be made to the arable land in all counties(cities)of the study area.At the same time,in order to maximize the economic,ecological,and social benefits,the grassland area will be adjusted accordingly,and forest land will be fully converted to forest land.In the forest area,there is an increase in the area of forest land to increase the green equivalent,so as to achieve the balance of regional water and land resources interaction.