Beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology, College of Water Sciences, Beijing Normal University, Beijing 100875, China.
Beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology, College of Water Sciences, Beijing Normal University, Beijing 100875, China.
Sci Total Environ. 2022 Aug 25;836:155472. doi: 10.1016/j.scitotenv.2022.155472. Epub 2022 Apr 26.
Studies have documented the significant effect of various factors on hydrological drought events. However, few studies have quantified drought's development and recovery process under environmental changes. This study focused on identifying hydrological drought's development and recovery characteristics and their potential causes in a typical semi-arid area. The Standardized Streamflow Index (SSI) was used as a metric for hydrological droughts, while the run theory was applied to identify the development and recovery processes of droughts. Changes in observed (human disturbed scenario) and simulated (natural scenario) droughts by employing the SWAT (Soil and Water Assessment Tool) model were also investigated from 1970 to 2016. The "simulated-observed" approach was used to assess the impacts of human regulations on hydrological drought development and recovery characteristics. Results showed that hydrological droughts occurred mainly during 1980-1990 and 2000-2016. In the natural condition, drought duration and intensity were higher, while lower severity in the drought recovery stage than development stage was observed. The drainage characteristics of the basin played the most critical role in the development and recovery characteristics of drought, which were also influenced by climatic conditions. Human activities had exacerbated recent natural hydrological drought. When considering the contribution of human activities, the reservoir operation was the dominant anthropic factor affected the development and recovery process of drought in the study area. Under the effects of reservoir regulation, long-duration hydrological droughts became rare. Moreover, the recovery ability of drought had been weakened. The effects of the reservoir were progressively crucial gradually. Although the water got from the river by the reservoir had been reduced, the negative impact on aggravating drought remains stronger than the reservoir was initially constructed. The results of our study will help improve the optimal management of reservoirs in semi-arid areas and enhance drought early warning and forecasting system.
研究已经记录了各种因素对水文干旱事件的显著影响。然而，很少有研究量化了环境变化下干旱的发展和恢复过程。本研究专注于识别典型半干旱地区水文干旱的发展和恢复特征及其潜在原因。标准水流指数（SSI）被用作水文干旱的度量标准，而径流理论则被用于识别干旱的发展和恢复过程。本研究还采用 SWAT（土壤和水评估工具）模型，从 1970 年到 2016 年，研究了观测（人为干扰情景）和模拟（自然情景）干旱的变化。采用“模拟-观测”方法评估了人类调控对水文干旱发展和恢复特征的影响。结果表明，水文干旱主要发生在 1980-1990 年和 2000-2016 年期间。在自然条件下，干旱持续时间和强度较高，而在干旱恢复阶段的严重程度较低。流域排水特征对干旱的发展和恢复特征起着最关键的作用，这些特征还受到气候条件的影响。人类活动加剧了最近的自然水文干旱。在考虑人类活动的贡献时，水库运行是影响研究区干旱发展和恢复过程的主要人为因素。在水库调节的影响下，长持续时间的水文干旱变得罕见。此外，干旱的恢复能力已经减弱。水库的影响逐渐变得至关重要。尽管从水库调水减少了，但对加剧干旱的负面影响仍然比水库最初建设时更强。我们的研究结果将有助于提高半干旱地区水库的优化管理水平，并增强干旱预警和预测系统。
