Le aree epicarsiche murgiane tra cambiamenti climatici e antropizzazione del territorio: l'area umida di Torre Castiglione, Conversano (Italia)

This paper deal with one of the lakes included in one of the main karst land of Italy, the Plateau of Murgia, made by Mesozoic carbonatic rocks of Apulian Platform. In this geological context, the Castiglione Lake is collocated: it is about a seasonal lake arising from bottom of a karst depression made impervious by accumulation of continental clay deposits. In the last three years, many hydrological and hydrogeological investigations on the lake and its cathment area have been carried out for studying in depth the knowledge of interactions and influences between surface water body and the underlying carbonatic aquifer. In particular, the analysis of climatic data showed that the last three-years period has been characterised by an increase of yearly average precipitations with summer supplies doubled and a groundwater recharge that represents about 30% of total rains. The chemical and physical analysis of surface waters showed that anthropic polluting phenomenon are negligible. The total dissolved salts range from 210 mg/l to 240 mg/l and is not related to precipitations an dry periods. Also the concentrations of nitrogenous group elements are low and are due to stagnation of surface water.