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由于过度施用化肥、使用农药、侵占农田等行为造成的农业环境和社会问题日益严重,尤其是在城郊农业区和高集约化农区问题更为突出,因此现代农业发展不仅仅追求经济效益,更应该关注生态功能提升和农村社会稳定.本研究旨在提出一套生态、经济和社会协调发展的土地利用结构优化方法,实现农业综合效益最大化和土地可持续发展.本研究以高集约化农业区长沙县为案例,首先构建经济-生态-社会效益评价指标体系,采用熵权-TOPSIS法对农业土地利用经济效益、生态效益和社会效益进行综合评价;其次采用耦合协调度模型和障碍因子模型,识别出影响农业综合效益的障碍因子;最后运用多目标线性规划法,构建生态、经济、社会约束条件和目标函数,计算得出土地利用最大综合效益和最优化结构,并提出了相关政策建议.研究结果表明:(1)长沙县农业综合效益呈现增长趋势,评价值从1996年的0.20上升到2016年的0.79;(2)经济因素不再是影响农业效益协调发展的障碍因子,而社会因素,例如粮食安全指数等成为主要影响因子;(3)综合考虑经济发展、环境保护和社会需求提出了长沙县土地利用优化结构,农业综合效益可由99.83亿元增长到129.34亿元,增长29.56％.本研究采用了一系列的模型和方法得出了长沙县农业综合效益最大化值和土地利用最优结构,可为农业土地空间格局优化和农业可持续发展提供科学的建议和依据.“,”Environmental and social problems caused by overfertilization, excessive pesticides, and encroachment on farmland are increasingly serious in agricultural settings, especially in suburban agricultural areas and highly intensive agricultural areas. Hence, modern agriculture not only pursues economic benefits, but it also pays more attention to ecological functions and social stability. This paper proposes a set of methods which are designed to realize optimal agricultural benefits and sustainable development by scientifically adjusting the land use structure. Taking Changsha County in South Central China as a case study, this paper first built an index system and adopted the information entropy-TOPSIS method to assess the economic, social, and ecological benefits of agricultural land use. Next, a coupled coordination model and an obstacle model were chosen to diagnose those factors that re-mained as obstacles to achieving the sustainable and coordinated development of the benefits of agricultural land use. Finally, based on the analysis of the changes in the benefits and obstacles over time, socio-economic and ecological constraints were established, and the multi-objective linear programming method (MOLP) was used to determine the comprehensive benefits and optimal land use structure. The results indicate that: (1) The agricultural benefits were stably increasing from 0.20 in 1996 to 0.79 in 2016. (2) The economic benefit index is no longer the main obstacle, while the social benefit index, which includes components such as the food security index, has be-come the principal influencing factor. (3) The optimal land use structure and comprehensive benefits were pre-sented by taking into consideration the economic development, environmental protection, and social needs. This study emphasizes economic development, but it also seeks coordinated development with comprehensive benefits. The results of the study could provide scientific recommendations for optimizing the agricultural land use spatial patterns and sustainable land use.