Nauditt Alexandra, Stahl Kerstin, Rodríguez Erasmo, Birkel Christian, Formiga-Johnsson Rosa Maria, Kallio Marko, Ribbe Lars, Baez-Villanueva Oscar M, Thurner Joschka, Hann Hamish
Institute for Technology and Resources Management in the Tropics and Subtropics, Cologne Technical, University of Applied Sciences, Germany.
Environmental Hydrological Systems, University of Freiburg, Germany.
Sci Total Environ. 2022 May 20;822:153493. doi: 10.1016/j.scitotenv.2022.153493. Epub 2022 Jan 31.
Droughts are causing severe damages to tropical countries worldwide. Although water abundant, their resilience to water shortages during dry periods is often low. As there is little knowledge about tropical drought characteristics, reliable methodologies to evaluate drought risk in data scarce tropical regions are needed. We combined drought hazard and vulnerability related data to assess drought risk in four rural tropical study regions, the Muriaé basin, Southeast Brazil, the Tempisque-Bebedero basin in Costa Rica, the upper part of the Magdalena basin, Colombia and the Srepok, shared by Cambodia and Vietnam. Drought hazard was analyzed using the variables daily river discharge, precipitation and vegetation condition. Drought vulnerability was assessed based on regionally available socioeconomic data. Besides illustrating the relative severity of each indicator value, we developed drought risk maps combining hazard and vulnerability for each grid-cell. While for the Muriaé, our results identified the downstream area as being exposed to severe drought risk, the Tempisque showed highest risk along the major streams and related irrigation systems. Risk hotspots in the Upper Magdalena were found in the central valley and the dryer Southeast and in the Srepok in the agricultural areas of Vietnam and downstream Cambodia. Local scientists and stakeholders have validated our results and we believe that our drought risk assessment methodology for data scarce and rural tropical regions offers a holistic, science based and innovative framework to generate relevant drought related information. Being applied to other tropical catchments, the approaches described in this article will enable the selection of data sets, indices and their classification - depending on basin size, spatial resolution and seasonality. At its current stage, the outcomes of this study provide relevant information for regional planners and water managers dealing with the control of future drought disasters in tropical regions.
干旱正在对全球热带国家造成严重破坏。尽管这些地区水资源丰富，但它们在干旱时期应对缺水的能力往往较低。由于对热带干旱特征了解甚少，因此需要可靠的方法来评估数据稀缺的热带地区的干旱风险。我们结合了与干旱危害和脆弱性相关的数据，以评估四个热带农村研究地区的干旱风险，这些地区分别是巴西东南部的穆里亚埃盆地、哥斯达黎加的坦皮斯克-贝贝德罗盆地、哥伦比亚马格达莱纳河盆地的上游地区以及柬埔寨和越南共有的斯雷博克地区。利用每日河流流量、降水量和植被状况等变量分析干旱危害。根据区域可用的社会经济数据评估干旱脆弱性。除了说明每个指标值的相对严重程度外，我们还绘制了干旱风险地图，将每个网格单元的危害和脆弱性结合起来。对于穆里亚埃地区，我们的结果表明下游地区面临严重干旱风险，而坦皮斯克地区沿主要河流和相关灌溉系统的风险最高。在上游马格达莱纳地区，风险热点位于中央山谷以及较为干旱的东南部，在斯雷博克地区，风险热点位于越南的农业区和柬埔寨下游。当地科学家和利益相关者已验证了我们的结果，我们相信我们针对数据稀缺的热带农村地区的干旱风险评估方法提供了一个全面、基于科学且创新的框架，以生成与干旱相关的有用信息。将本文所述方法应用于其他热带集水区，将能够根据流域大小、空间分辨率和季节性选择数据集、指标及其分类。在当前阶段，这项研究的成果为应对热带地区未来干旱灾害控制的区域规划者和水资源管理者提供了相关信息。
