Mahmoud Shereif H, Alazba A A, Adamowski J, El-Gindy A M
Alamoudi Water Research Chair, King Saud University, Riyadh, Saudi Arabia,
Environ Monit Assess. 2015 Sep;187(9):598. doi: 10.1007/s10661-015-4822-x. Epub 2015 Aug 28.
Identification of potential sites for rainwater harvesting (RWH) is an important step toward maximizing water availability and land productivity in arid semiarid regions. Characterised as a "water scarce" country, Egypt has limited fresh water supplies, and is expected to suffer from water stress by the year 2030. Therefore, it is important to develop any means available to supply water and maintain human habitability in a sustainable manner. Practiced or simply indispensable in many countries around the world, rainwater harvesting (RWH) promotes a sustainable and efficient manner of exploiting water resources. In the present study, suitable areas for sustainable stormwater harvesting and storage in Egypt were identified using remote sensing for land cover data - location assessment linked to a decision support system (DSS). The DSS took into consideration a combination of thematic layers such as rainfall surplus, slope, potential runoff coefficient (PRC), land cover/use, and soil texture. Taking into account five thematic layers, the spatial extents of RWH suitability areas were identified by an analytical hierarchy process (AHP). The model generated a RWH map with five categories of suitability: excellent, good, moderate, poor and unsuitable. The spatial distribution of these categories in the area investigated was such that 4.8% (47910 km(2)) and 14% (139739 km(2)) of the study area was classified as excellent or good in terms of RWH, respectively, while 30.1% (300439 km(2)), 47.6% (474116 km(2)) and 3.5% (34935 km(2)) of the area were classified as moderate, unsuitable and poor, respectively. Most of the areas with excellent to good suitability had slopes of between 2% and 8% and were intensively cultivated areas. The major soil type in the excellent suitability areas was loam, while rainfall ranged from 100 to 200 mm yr(-1). The use of a number of RWH sites in the excellent areas is recommended to ensure successful implementation of RWH systems.
确定雨水收集（RWH）的潜在地点是在干旱半干旱地区最大限度提高水资源可用性和土地生产力的重要一步。埃及被视为“缺水”国家，淡水供应有限，预计到2030年将面临水资源紧张状况。因此，开发任何可用手段以可持续方式供水并维持人类宜居性非常重要。雨水收集在世界许多国家都有实践或必不可少，它促进了一种可持续且高效的水资源开发方式。在本研究中，利用遥感获取土地覆盖数据——与决策支持系统（DSS）相关联的位置评估，确定了埃及可持续雨水收集和储存的适宜区域。该决策支持系统考虑了降雨盈余、坡度、潜在径流系数（PRC）、土地覆盖/用途和土壤质地等多种专题图层。考虑到五个专题图层，通过层次分析法（AHP）确定了雨水收集适宜区域的空间范围。该模型生成了一张雨水收集适宜性地图，分为五个类别：极佳、良好、中等、较差和不适宜。这些类别的空间分布在研究区域内，就雨水收集而言，分别有4.8%（47910平方公里）和14%（139739平方公里）的研究区域被归类为极佳或良好，而该区域分别有30.1%（300439平方公里）、47.6%（474116平方公里）和3.5%（34935平方公里）被归类为中等、不适宜和较差。大多数适宜性极佳到良好的区域坡度在2%至8%之间，且为集约耕种区域。极佳适宜性区域的主要土壤类型是壤土，年降雨量在100至200毫米之间。建议在极佳区域使用多个雨水收集地点，以确保雨水收集系统的成功实施。
