干旱地区生态环境需水评价研究——以民勤县为例

Evaluation of ecological environment water demand in arid area——taking Minqin County as an example

为科学准确的评价半干旱地区生态环境需水状况,对生态环境需水评价概念进行概括,以"自然-水资源-社会经济-生态"复合系统为研究角度,建立1目标、4准则, 29指标的半干旱地区生态环境需水评价体系,将熵值理论引入层次分析法结合计算指标权重以消除主观经验对结果的影响,以半干旱地区民勤县为例,使用模糊综合评价法对该地区2006-2015年的生态环境需水及其子系统状况进行评价分析。结果表明:①对半干旱地区生态需水评价指数影响最大的是"水资源"子系统与"生态"子系统;缺水量、年平均水资源量、生态用水量占比、地均水资源量及人均水资源量为影响力最大指标。②近十年民勤县的生态环境需水处于"较差"转向"一般"的阶段,与各子系统的协调度逐年变好,说明该地生态治理取得了成效。该方法可应用于类似半干旱地区的生态环境需水评价,为半干旱地区制定水资源调控战略及生态需水研究奠定一定的理论基础。

In order to evaluate the eco-environmental water requirement scientific and accurately in semi-arid areas, this paper summarized the concept of eco-environmental water demand assessment and set up the evaluation system of eco-environmental water demand in semi-arid area with 1 target, 4 criteria and 29 indexes based on the complex system of "natural-water resource-economic-ecology". The entropy value theory and the analytic hierarchy process were combined to calculate the index weight, which eliminated the influence of subjective experience on the result. Taking Minqin County in semi-arid area as an example, this paper evaluated and analyzed the condition of ecological environment water demand and its subsystem in this area for 2006-2015 year by using fuzzy comprehensive evaluation method. The results showed that the most important influence of ecological water demand Evaluation index was "water resource" subsystem and "ecological" subsystem, the most influential index was the quantity of water shortage, average annual amount of aquatic resources, ecological water consumption ratio, the amount of ground water resources and the amount per capita. In the last ten years, the water demand of ecological environment in Minqin County has been in the stage of "poor" to "general", and the coordination degree of each subsystem becomes better every year. The evaluation result is consistent with the actual situation. This method can be applied to the assessment of eco-environmental water demand in semi-arid area, which lays a theoretical foundation for the development of water Resources control strategy and ecological water demand research in semi-arid area.