The management of droughts is a challenging issue, especially in water scarcity areas, where this problem will be exacerbated in the future. The aim of this paper is to identify potential groundwater (GW) bodies with reduced vulnerability to pumping, which can be used as buffer values to define sustainable conjunctive use management during droughts. Assuming that the long term natural mean reserves are maintained, a preliminary assessment of GW vulnerability can be obtained by using the natural turnover time (T) index, defined in each GW body as the storage capacity (S) divided by the recharge (R). Aquifers where R is close to S are extremely vulnerable to exploitation. This approach will be applied in the 146 Spanish GW bodies at risk of not achieving the Water Framework Directive (WFD objectives, to maintain a good quantitative status. The analyses will be focused on the impacts of the climate drivers on the mean T value for Historical and potential future scenarios, assuming that the Land Use and Land Cover (LULC) changes and the management strategies will allow maintenance of the long term mean natural GW body reserves. Around 26.9% of these GW bodies show low vulnerability to pumping, when viewing historical T values over 100 years, this percentage growing to 33.1% in near future horizon values (until 2045). The results show a significant heterogeneity. The range of variability for the historical T values is around 3700 years, which also increases in the near future to 4200 years. These T indices will change in future horizons, and, therefore, the potential of GW resources to undergo sustainable strategies to adapt to climate change will also change accordingly, making it necessary to apply adaptive management strategies.

中文翻译：

---

使用周转时间指数确定潜在的战略地下水资源以管理西班牙大陆的干旱

干旱管理是一个具有挑战性的问题，特别是在缺水地区，这个问题在未来会更加严重。本文的目的是确定对抽水的脆弱性降低的潜在地下水 (GW) 体，这些水体可用作缓冲值，以定义干旱期间的可持续联合使用管理。假设长期自然平均储量保持不变，利用自然周转时间（T）指数可以初步评估GW脆弱性，在每个GW体中定义为存储容量（S）除以补给（R） . R 接近 S 的含水层极易受到剥削。这种方法将应用于面临无法实现水框架指令（WFD 目标，以保持良好的定量状态）风险的 146 个西班牙 GW 机构。分析将侧重于气候驱动因素对历史和潜在未来情景的平均 T 值的影响，假设土地利用和土地覆盖 (LULC) 发生变化，并且管理策略将允许维持长期平均自然 GW身体储备。在查看 100 多年的历史 T 值时，这些 GW 主体中约有 26.9% 显示出较低的抽水脆弱性，在不久的将来（直到 2045 年）这个百分比增长到 33.1%。结果显示出显着的异质性。历史 T 值的变异范围约为 3700 年，在不久的将来也会增加到 4200 年。这些 T 指数将在未来发生变化，因此，GW 资源进行可持续战略以适应气候变化的潜力也将相应改变，