中文摘要：

洪水资源利用生态适度性，是指在洪水资源利用时应保障河道内生态需水量，包括河道最小生态需水量、适宜生态需水量和脉冲性生态需水量。以淮河为背景，提出了计算最小生态需水量、适宜生态需水量及脉冲性生态需水量的方法，以及洪水资源利用生态适度性的划分标准。应用结果表明，淮河洪水资源利用生态适度性的阈值为汛期天然径流量的30％。此时，淮河洪水资源利用仍有潜力。

英文摘要：

A concept of ecological moderate criteria of floodwater utilization was proposed. Its core is that utilization of floodwater in flood season should satisfy the ecological water demands, including steady demand of ecological water and flood pulse. In a case study of Huai River, the Huai River approach was used to calculate the steady demand of ecological water, and a division criteria of artificial flood pulse was established through an analysis of ecological demand and historical statistical data. The results show that in flood season, if the steady demand of ecological water and the flood pulse are considered, roughly 30% of the natural runoff should be preserved for the ecological system. Meanwhile, under the presently studied criteria the Huai River still has some potentiality for floodwater utilization.