Instituto Pirenaico de Ecología, Consejo Superior de Investigaciones Científicas (IPE-CSIC), Campus de Aula Dei, 50080 Zaragoza, Spain.
Instituto Pirenaico de Ecología, Consejo Superior de Investigaciones Científicas (IPE-CSIC), Campus de Aula Dei, 50080 Zaragoza, Spain.
Sci Total Environ. 2021 Apr 20;766:142610. doi: 10.1016/j.scitotenv.2020.142610. Epub 2020 Oct 3.
Mediterranean mountain forests play a significant role in hydrological regulation. In this study, hydrological dynamics was examined at different temporal scales in a small mountain forest catchment in the Central Spanish Pyrenees (San Salvador), based on a 20-year dataset (1999-2019). Mean annual runoff coefficient is 0.21, and ranged from 0.02 to 0.58. The catchment has a bi-modal hydrological behavior with two hydrological periods: a dry-period between July and December, and a wet-period between January and June. During the study period, only 108 floods were recorded, suggesting a low responsiveness of the catchment, with a high variable response. Spearman correlation analysis and stepwise multivariate regression suggest that the hydrological response in the San Salvador catchment is mainly depending on water table, with antecedent moisture conditions and rainfall depth as secondary factors. Seasonal differences were also observed: during dry season, the response was mainly related to rainfall depth and rainfall intensity; in contrast in wet season, the response was mainly related to antecedent conditions (previous rainfall and base flow). Thus, the already challenging water resources management in the Mediterranean basin is magnified by the key function of forests as natural modulators of water cycle. Consequently, the study of natural forested catchments is needed and long-datasets have to be analysed to understand the role of natural Mediterranean forest in the hydrological dynamics and its evolution and adaptation in a context of Global Change.
地中海山区森林在水文调节方面发挥着重要作用。本研究基于 20 年（1999-2019 年）数据集，在西班牙中部比利牛斯山脉的一个小山区森林流域（圣萨尔瓦多），从不同时间尺度研究了水文动态。平均年径流系数为 0.21，范围为 0.02 至 0.58。该流域具有双模态水文特征，有两个水文期：7 月至 12 月的干旱期和 1 月至 6 月的湿润期。在研究期间，仅记录到 108 次洪水，表明流域响应较低，具有高度的可变响应。Spearman 相关分析和逐步多元回归表明，圣萨尔瓦多流域的水文响应主要取决于地下水位，前期湿度条件和降雨深度为次要因素。还观察到季节性差异：在旱季，响应主要与降雨量和降雨强度有关；而在雨季，响应主要与前期条件（前期降雨和基流）有关。因此，森林作为水循环的天然调节剂的关键功能放大了地中海盆地已经具有挑战性的水资源管理。因此，需要研究天然森林流域，并分析长数据集，以了解天然地中海森林在水文动态及其在全球变化背景下的演变和适应中的作用。
