lower reaches of river meaning in English

河流下游

In consideration of the characteristics of ecological environment water supply , the opportunity cost method is adopted to calculate its shadow price , and a method is put forward for calculating the economic benefit of ecological environment water supply on the basis of the economic benefit from agricultural irrigation based on the level of guarantee of water supply to water consumption departments on the lower reaches of rivers
摘要针对生态环境供水的特点，采用机会成本法分析生态环境供水经济效益并计算其影子价格；并根据河流下游各用水部门供水保证程度，提出借助农业灌溉经济效益计算生态环境供水经济效益的方法。