Silvino Castaño

El control de los recursos hídricos fue un objetivo fundamental para la Monarquía Hispánica en La Mancha durante la Edad Moderna. La desecación en 1751 de la superficie encharcada que forma el actual Parque Nacional de Las Tablas de Daimiel, promovida por Fernando VI, es un buen ejemplo de dicho control. Este artículo analiza los principales factores que confluyeron en aquella decisión que supuso la primera gran obra hidráulica de la monarquía borbónica en la cuenca del Guadiana. Para ello se ha estudiado, principalmente, la evolución de los molinos harineros del entorno de Las Tablas de Daimiel durante la Edad Moderna, los conflictos ocasionados por el control del caudal y la climatología de la zona durante la época estudiada. La presión de los molineros sobre el río y el aumento de la aridez provocaron una creciente conflictividad que la monarquía intentó resolver con la desecación. Sin embargo, el principal objetivo fue satisfacer los intereses recaudatorios de la monarquía y los de una serie de ganaderos de la zona vinculados al rey.

Some researchers have proposed the groundwater protection zone (GPZ) method as a methodological framework for defining safeguard zones of groundwater bodies. Its goal is to protect the quality of water intended for human consumption and to facilitate a common implementation of this method in all European Union member states. One of the criteria used to establish GPZs is to define contributing catchment areas (CCAs). This methodology has been applied to the Sierra de Cañete, a region comprising a carbonate aquifer in the province of Malaga, Spain. The tools used to define CCAs are hydro-chemical and isotopic characterizations, namely water isotopes (i.e., ²H, ¹⁸O and tritium) and the isotopes of dissolved sulfates (i.e., ³⁴S and ¹⁸O). Traditionally, the Sierra de Cañete aquifer has been divided into six sectors. Hydro-chemical and isotopic characterization differentiated between two large areas in the carbonate aquifer. The southern part presents younger water that is the result of faster recharge and that shows a high level of karstification, while the northern area has a slower flow, and recharge is produced over several years. In addition, the northern part is hydraulically connected to an alluvial aquifer (i.e., Llanos de Almargen) that borders the Sierra de Cañete to the north. This aquifer has high levels of pollution due to agricultural and livestock activities carried out in the Llanos de Almargen area. This pollution is transmitted to the carbonate aquifer when groundwater depletion occurs. Therefore, the Sierra de Cañete GPZ needs to be extended to include the Llanos de Almargen aquifer.

Artesian springs are localized aquifer outlets that originate when pressurized ground water is allowed to rise to the surface. Computing artesian discharge directly is often subject to practical difficulties such as restricted accessibility, abundant vegetation or slow flow rates. These circumstances call for indirect approaches to quantify flow. This paper presents a method to estimate ground water discharge through an upwelling spring by means of a three‐layer steady‐state groundwater flow model. Model inputs include on‐site measurements of vertical sediment permeability, sediment temperatures and hydraulic gradients. About 70 spring bed piezometers were used to carry out permeability tests within the spring sediments, as well as to quantify the hydraulic head at different depths below the discharge point. Sediment temperatures were measured at different depths and correlated to permeabilities in order to demonstrate the potential of temperature as a substitute for cumbersome slug tests. Results show that the spatial distribution of discharge through the spring bottom is highly heterogeneous, as sediment permeability varies by several orders of magnitude within centimetres. Sensitivity analyses imply that geostatistical interpolation is irrelevant to the results if field datasets come from a sufficiently high resolution of piezometric records. Copyright © 2013 John Wiley & Sons, Ltd.