Impactos recientes de los cambios ambientales en los recursos hídricos superficiales de la cuenca del Duero

In recent decades, the environmental changes due to human development have put pressure on water resources in the Mediterranean basin, a region where availability of water has been historically limited. In this work we analyze the evolution and variability (1961-2005) of streamflows in one of the largest rivers basin of the Iberian Peninsula, the Duero River basin. Moreover, the factors responsible for such evolution are assessed. Results show a significant and generalized decrease of water resources in the basin, together with changes in the timing of monthly distribution. Climate itself, with quasi-stationary precipitation and increasing temperatures in the long-term, is not enough to explain the decreasing streamflows. Thus, observed land-cover expansion in the headwaters is thought to be increasingly contributing to the hydrological depletion. On the other hand, impoundment of water through dams is increasing in the basin and consequently contributing the hydrological change. Results offer the basis for future projections of water availability in scenarios of water scarcity due to forthcoming climate change