基于虚拟水战略的农业种植结构优化模型

以往灌区水资源优化配置研究着重于经济效益而忽视了社会效益和生态效益，这不适于生态环境及人类生存环境极其脆弱的西北干旱缺水地区。该文在总结原有优化模型基础上通过设置当地人民生产生活条件及环境改善对物质水需求的刚性约束条件，提出基于虚拟水战略的区域农业产业结构优化模型，并以民勤县为例进行模拟计算。结果表明，随着虚拟水贸易系数的增加，粮食作物的种植面积有所减少，而蔬菜类作物的种植面积大幅度增加；其经济效益与用水效益都明显提高，区域粮食依赖性也随之加剧。方案7、8在贸易基础上实施技术节水，在一定程度上保证了粮食安全，节约了宝贵的水资源，有利于旱区生态环境改善。该模型求解出的优化方案为制定合理有效的旱区农业产业结构调整政策有一定的借鉴作用。

Optimal regional agricultural planting structure under virtual water strategy

In the past, the research of optimal allocation of irrigation of water resources was focused on the economic benefits. It had ignored the social and ecological benefits, and was not suitable for the extremely fragile and arid areas of northwest. Based on the idea of the original optimization model, this paper proposed the virtual water strategy optimization model of regional agricultural structure by setting up the rigidity constraints for local production, living conditions and water demanding to environmental improvement. Then, Minqin County was taken as an example. The results showed that the food crop acreage decreased, the vegetable crop area increased significantly with the coefficient of virtual water trade increasing. Its economic efficiency and water-use efficiency were markedly improved, and the food dependency also would be gradually increased. The trading foundation and water-saving technology could ensure the food security. Saved valuable water resource was conducive to the improvement of the ecological environment in drought region. Solving the optimization program will be helpful to develop a rational and effective policy of industrial restructuring.