Land use optimization of plateau lake basin based on town-agriculture-ecological spatial coordination

Abstract: In order to understand the current situation of land use layout in the plateau lake basin and explore the optimal allocation of land use space in the plateau lake basin based on urban-agriculture-ecology coordination, the paper takes the Fuxian Lake Basin as an example, based on the 3S technology, and uses the MCR-CLUE-S model to study the structure and layout of town-agriculture-ecological space in 2030 under the four modes of urban construction scenario, cultivated land development scenario, ecological protection scenario and integrated optimization scenario in the Fuxian Lake Basin. Finally, the optimal allocation of land use space under the coordination of town-agriculture-ecological space in Fuxian Lake Basin is proposed. The results show: 1) From 2005 to 2015, in the Fuxian Lake Basin, the urban space is on the rise, the agricultural space is in a downward trend, and the ecological space is rising first and then decreasing. The spatial distribution pattern is basically the same in 10 years. 2) The paper selects important water source, lakeside wetland and large-scale natural forest land as protection sources, 8 resistance factors such as elevation and slope are selected. The minimum cumulative resistance model and the cumulative cost distance model are used to construct the ecological security pattern of the Fuxian Lake Basin, as well as the "source" core area, ecological protection area, ecological margin area, agricultural development area, agricultural fringe area and urban construction area which are conducive to ecological protection. 3) Taking the ecological functional partition area in the ecological security pattern as a constraint, based on the Markov model's calculation of the number of land types, and simulating the town-agriculture-ecological space optimization layout in the urban construction scenario, agricultural development scenario and ecological protection scenario of the Fuxian Lake Basin in 2030 through the CLUE-S model. The urban construction scenario takes into account the current needs of life, and the development of the number and spatial structure of town-agriculture-ecological space led by the development of urban space under the guidance of policies; the agricultural development scenario controls the size of urban space and develops part of the ecological space potential; the area of agricultural space has decreased under the ecological protection scenario, and the urban space area has increased slightly. 4) In the 2030 comprehensive optimization scenario of the Fuxian Lake Basin, seven spatial types are classified according to different land functions: Urban space, agricultural space, ecological space, urban-agricultural space, urban-ecological space, agriculture-ecological space and town-agriculture-ecological space.There are large differences in various types of space: Agriculture - ecological space is minimal, ecological space is maximum. 5) By analyzing the advantages of regional development in four cases and combining with various factors such as cultivated land protection, ecological protection and socioeconomic development in the Fuxian Lake Basin, the study considers that the integrated scenario is more reasonable and more suitable for local development, while the other three single-element scenarios can complement and adjust the implementation of the integrated scenario. The research results provide reference for the decision-making of land space planning and ecological protection strategy in Fuxian Lake Basin.