The analysis of the hydrological response to meteorological drought events can lead to a deeper understanding of alterations in hydrological processes that can be used to help maintain environmental flow (e-flow) in aquatic ecosystems. In this study, we first identified an extreme meteorological drought event and then assessed its hydrological response. Monthly precipitation anomalies were used to identify meteorological drought, while the Lyne–Hollick method (LH filter) was used alongside the baseflow recession constant (calculated using the Automatic Baseflow Identification Technique [ABIT]) to isolate baseflow in the Baiyangdian basin. Results showed that an extreme meteorological drought event occurred in August 1996, continuing for a total of 127 months, which resulted in prolonged hydrological drought (i.e., streamflow and baseflow). A time lag was generally observed between the end of the meteorological drought event and the end of the hydrological drought event, where baseflow recovery lagged behind streamflow (runoff) recovery. Additionally, drought led to an unstable shift in the precipitation-streamflow relationship that subsequently led to a reduction in the annual streamflow of coinciding annual precipitation compared with the historical relationship. Drought also led to a longer response between precipitation and runoff events. Results from this study show that the hydrological response to meteorological drought event is important for water resource management and for addressing effects related to climate change, especially extreme drought events.

中文翻译：

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多年干旱的水文响应评估：滞后特征和变化幅度的见解

对气象干旱事件的水文响应分析可以更深入地了解水文过程的变化，这些变化可用于帮助维持水生生态系统中的环境流量（e-flow）。在这项研究中，我们首先确定了一个极端气象干旱事件，然后评估了它的水文响应。月降水异常用于识别气象干旱，而Lyne-Hollick方法（LH过滤器）与基流衰退常数（使用自动基流识别技术[ABIT]计算）一起用于隔离白洋淀盆地的基流。结果表明，1996年8月发生了一次极端气象干旱事件，共持续了127个月，造成了长时间的水文干旱（即径流和基流）。在气象干旱事件结束和水文干旱事件结束之间通常观察到时间滞后，其中基流恢复滞后于径流（径流）恢复。此外，干旱导致降水-流量关系的不稳定转变，随后导致与历史关系相比，同时年降水量的年流量减少。干旱还导致降水和径流事件之间的响应时间更长。这项研究的结果表明，对气象干旱事件的水文响应对于水资源管理和解决与气候变化有关的影响，尤其是极端干旱事件具有重要意义。其中基流恢复落后于径流（径流）恢复。此外，干旱导致降水-流量关系的不稳定转变，随后导致与历史关系相比，同时年降水量的年流量减少。干旱还导致降水和径流事件之间的响应时间更长。这项研究的结果表明，对气象干旱事件的水文响应对于水资源管理和解决与气候变化有关的影响，尤其是极端干旱事件具有重要意义。其中基流恢复落后于径流（径流）恢复。此外，干旱导致降水-流量关系的不稳定转变，随后导致与历史关系相比，同时年降水量的年流量减少。干旱还导致降水和径流事件之间的响应时间更长。这项研究的结果表明，对气象干旱事件的水文响应对于水资源管理和解决与气候变化有关的影响，尤其是极端干旱事件具有重要意义。干旱导致降水-流量关系的不稳定转变，随后导致与历史关系相比，同时年降水量的年流量减少。干旱还导致降水和径流事件之间的响应时间更长。这项研究的结果表明，对气象干旱事件的水文响应对于水资源管理和解决与气候变化有关的影响，尤其是极端干旱事件具有重要意义。干旱导致降水-流量关系的不稳定转变，随后导致与历史关系相比，同时年降水量的年流量减少。干旱还导致降水和径流事件之间的响应时间更长。这项研究的结果表明，对气象干旱事件的水文响应对于水资源管理和解决与气候变化有关的影响，尤其是极端干旱事件具有重要意义。