Hydro-geomorphologycal dynamic and man induced processes in el Partido River (NW National Park of Doñana, Spain). Analysis of current processes

Abstract

Actual hydrogeomorphological processes and human pressure are analyzed in el Partido River. This fluvial system has intensely destabilized following a severe, diverse and prolonged human impact on slopes and channels. The sandy material input to the wetlands of Doñana through this small Mediterranean river (located at Huelva Province, SW Spain) is one of the main concerns to conservation of the Doñana National Park. In the Partido watershed, impacts mainly come from the land use change: removal of native vegetation for agricultural activity, replacement of traditional crops by others who need more aggressive tillage techniques, clearance for the cultivation of eucalyptus and gravel mining, less permeable linear infrastructure, etc.; while the riparian zone, besides having lost native vegetation and be occupied in many ways, are being managed improperly by removing bottom sediment, destruction of morphology of banks and channel-floodplain disconnection (flumes, straightened tranches, artificial elevation of banks, etc.). This has led to increased erosive capacity of the fluvial system for lasts decades, so exorbitant increasing volumes of transported sediment to the Guadalquivir marshes.