La evaluación de la recarga como contribución al conocimiento hidrogeológico del acuífero carbonático de la Sierra de la Silla (Parque Natural de la Sierra de Grazalema, Cádiz)

Resumen

The Sierra de la Silla aquifer is the smallest (10 km2 of permeable outcrops) and westernmost aquifer forming part of the Grazalema Natural Park, situated to the NE of the Cádiz province. Previous works suggested its detailed investigation, due to the fact that it was supposed to be a representative subsystem of the karstic aquifers forming the hydrogeological unit of Sierra de Grazalema and, in addition, a straightforward system to be studied. The continuous monitoring of the flow rate of La Esparragosilla sprong (though to represent the main discharge zone of the whole aquifer) and the comparison of such flow rate with diverse and independent estimations of the value of the recharge (daily soil water budget, chloride mass balance and the APLIS method), allowed us to prove that the recharge in this aquifer is markedly higher than the discharge of the cited spring. The distribution of the outflows through different sectors of the aquifer and its small dimensions hinders the development of organized conduit network, being this circumstance different from other know karstic aquifers of the Grazalema Natural Park. For these reasons, the hydrogeological functioning of the carbonate aquifer of Sierra de la Silla was found to be poorly representative of the majority of the carbonate aquifers of Sierra de Grazalema.