黄土高原典型区雨水资源化潜力模拟与评价

Simulation and Evaluation of Rainwater Harvesting Potential in Typical Areas of Loess Plateau

为充分利用雨水资源应对黄土高原水土流失和干旱缺水的问题,引入分布式水文模拟技术,构建具有物理成因机制的分布式雨水资源化潜力评估模型,解决雨水资源利用的核心问题--评价当地的雨水资源化潜力。通过研究黄土高原典型区域黄河河口镇至龙门段(河龙区间)的雨水资源情况,定量评估该区域雨水资源化潜力,结果表明:在气候变化和人类活动的双重背景下,20世纪80年代后,黄河流域河龙区间的地表径流量、土壤有效水增量和雨水资源化潜力呈现上升趋势;河龙区间大部分地区雨水资源呈增长趋势,雨水资源可基本满足现有条件下区域植被恢复的用水需求。气候变化对雨水资源化潜力起正影响作用,贡献率为63.4%,土地利用/覆盖变化则为负影响,贡献率为-36.6%。人类活动对区域雨水资源利用的影响不容忽视,应大力发展干旱半干旱区降雨-径流调控技术,提高雨水资源化利用率,以保障区域生态-经济协同可持续发展。

The rational use of rainwater resources can not only reduce the source of soil erosion,but also provide effective water supply to the local area.The Loess Plateau has less precipitation,large evaporation,and very scarce surface water resources.Therefore,the use of rainwater resources has become an important means for the Loess Plateau to deal with soil erosion,drought and water shortage.The core issue of rainwater resource utilization is to scientifically evaluate the local rainwater resource potential and its spatial and temporal distribution.For this reason,the distributed hydrological simulation technology was introduced to construct a distributed rainwater harvesting potential assessment model.It was dedicated to solving the core problems of rainwater resource utilization and evaluate the potential of local rainwater resources.The following conclusions were drawn by studying the typical Helong Region of the Loess Plateau.Under the dual influences of climate change and human activities,the surface runoff,soil water increment and the rainwater harvesting potential in Helong Region showed an upward trend after 1980 s.The rainwater resources of most sub-basins in the Helong Region had a growing trend,and the rainwater resources could basically meet the water consumption under the current vegetation coverage.Climate change had a positive impact on rainwater resources with the contribution rate of 63.4%and the land use/cover change had a negative impact with the contribution rate of-36.6%.Therefore,the human activities imposed great effect on rainwater utilization pattern,and to fully develop the rainfallrunoff regulation technologies and improve the rainwater using efficiency were the key countermeasures to realize the ecology-economy synergetic development in the Loess Plateau.