基于多目标优化的石羊河流域农业种植结构优化OA

[Objective]The Shiyang River Basin is a typical arid basin in Northwestern China that faces severe water scarcity and an unbalanced cropping structure.In this paper,we propose a multi-objective optimization method to optimize the regional agricultural planting structure.[Method]This study was based on water footprint theory to analyze the spatiotemporal changes in blue and green water footprints of three major crops(wheat,maize and vegetables)cultivated across five counties and districts in the basin from 2000 to 2024,including Minqin County,Gulang County,Liangzhou District,Jinchuan District,and Jinchang County.On this basis,a multi-objective optimization model considering both economic and ecological benefits was established to determine the optimal planting structure for the region.[Result]①Maize dominated the water footprint in Liangzhou District,accounting for 46.61%of the total water footprint of the three crops;the blue water footprint of vegetables accounted for 39.67%of the total crop water footprint.Among all studied regions,Jinchuan District had the lowest total crop water footprint,with its green water footprint accounting for only 0.31%of the total water footprint.②The Pareto-optimal planting structure yielded a total blue water footprint of 2.489 billion m3,saving 356 million m3 of water compared with the baseline scenario,while delivering an economic benefit of 12.046 billion CNY.[Conclusion]The Pareto-optimized planting structure is specified as follows:increasing the maize planting area to 128 320 hm2,reducing the wheat cultivated area to 57 220 hm2,and adjusting the vegetable planting area to 52 000 hm2.These changes can effectively reduce the regional blue water footprint and improve economic returns,facilitating the sustainable utilization of water resources in the basin.