Centre of Hydrogeology of the University of Málaga (CEHIUMA), Spain.
Groundwater Hydrology Group, Dept. Civil and Environmental Eng., Technical University of Catalonia (UPC), Spain; Hydromodel Host S.L. and Aquageo Proyectos S.L., Spain.
Sci Total Environ. 2018 Nov 1;640-641:874-893. doi: 10.1016/j.scitotenv.2018.05.305. Epub 2018 Jun 5.
In many of the alpine watersheds of Sierra Nevada (Southern Spain) exists an ancient network of dug canals that collect, transport and facilitate the recharge the snowmelt in the underlying aquifer during the spring season. This practice, known as careos, in the lower part of the watersheds supply drinking water as spring discharge during the dry season. To study how this managed recharge technique modifies the natural response of these basins this work focuses on characterizing the hydrological behavior of one of the sites, the Berchules watershed. The mechanisms for mineralization of groundwater are based on geochemical processes such as evapo-concentration in the soil layer and silicate mineral weathering due to dissolved CO originated from both soil biogenic processes and the atmosphere. Groundwater presents a main hydrogeochemical calcium‑magnesium-bicarbonate type facies, which is associated to groundwater flowing through the upper weathered silicates and quickly drained through springs located in the uplands and in the intermediate altitude catchment zone. Additionally, in the lower part of the basin some springs discharge mineralized groundwater with a sodium-calcium-bicarbonate composition associated to regional groundwater flow. In natural conditions, this hydrogeological system behaves as a sloping aquifer, occurring recharge between 1400 and 2500 m a.s.l. The springs discharge groundwater with an isotopic content and temperature in coherence with the local rainfall isotopic and thermal atmospheric altitudinal lines. Nevertheless, once the careo recharge begins the affected springs reveal the fingerprint of the concentrated recharge system by blurring the fingerprint of both the isotopic and thermal altitudinal dependence in the springs discharge. This validates the previous conceptual model and supports average recharge values of 141 ± 140 mm/yr and total average water resources of 181 ± 111 mm/yr which include a 40% increase in the study period due to the effect of the acequias de careo.
在内华达山脉（西班牙南部）的许多高山流域都存在着古老的沟渠网络，这些沟渠在春季收集、输送和促进积雪融水补给到下面的含水层。在流域的下游，这种做法被称为 careos，它在旱季为泉水提供饮用水。为了研究这种管理的补给技术如何改变这些流域的自然响应，这项工作侧重于表征其中一个地点——Berchules 流域的水文行为。地下水的矿化机制基于地球化学过程，如土壤层中的蒸发浓缩和由于土壤生物过程和大气中溶解的 CO2 引起的硅酸盐矿物风化。地下水呈现出主要的水文地球化学钙镁碳酸氢盐类型相，与通过上层风化硅酸盐并通过位于高地和中间海拔集水区的泉水迅速排出的地下水有关。此外，在流域的下部，一些泉水排放矿化地下水，其组成与区域地下水流动有关，含有钠钙碳酸氢盐。在自然条件下，这个水文地质系统表现为一个倾斜的含水层，在 1400 到 2500 米的海拔高度之间进行补给。泉水排出的地下水具有与当地降雨同位素和大气海拔热同位素线一致的同位素含量和温度。然而，一旦 careo 补给开始，受影响的泉水就会通过模糊泉水排放的同位素和热海拔依赖关系的指纹，显示出浓缩补给系统的指纹。这验证了之前的概念模型，并支持平均补给值为 141±140 毫米/年，总平均水资源为 181±111 毫米/年，这包括由于 acequias de careo 的影响，研究期间增加了 40%。
