Assessing hydrological and sediment connectivity in contrasting Mediterranean catchments. Impacts of Global Change
MEDhyCON project intends to investigate changing patterns of hydrological and sediment connectivity induced by climate and land use changes in Mediterranean catchments by using a sediment budget assembled with several methods when applied to likely scenarios of global change. The SWAT model, previously validated with the sediment budgets, may also be used to anticipate the catchment response to these changes. Research will be focused on three catchments in a decreasing a priori range of connectivity and increasing size: the small Vallcebre catchment (4 km2) in the South-Eastern Pyrenees, the Sant Miquel catchment (151 km2) in the Serra de Tramuntana of Mallorca Island, and the Na Borges catchment (319 km2) in the Central Depression of Mallorca Island. The objectives of the project are: 1) To develop a sediment budget as a perceptual model of hydrological and sediment connectivity by applying a multi-technique approach within the three catchments. GIS modelling, sediment-tracer techniques and continuous monitoring of water and sediment fluxes will be used to develop an understanding of catchment response. 2) To develop further the application of 137Cs fallout radionuclide to the study of soil traslocation, erosion and sediment tracing. Particular attention will be addressed to the various sources of uncertainty. Results obtained from the application of the improved techniques will be used to improve the perceptual model developed in (1). 3) To investigate contaminant transfer by water and sediment through the fluvial system and to assess the impact of such contaminants on the downstream wetlands of the Mallorcan catchments, giving particular attention to the effects of land use. 4) To apply the SWAT model for continuous simulation of water, sediment and associated contaminant fluxes to the study catchments. This model will be adapted to reflect the perceptual model developed for the study catchments. Once validated and calibrated the SWAT model will be used to simulate the hydrological and sediment connectivity under different global change scenarios (i.e. land use and climate changes) in the two larger catchments. 5) To implement a Spatial Data Infrastructure (SDI) containing referenced information resulting from continuous monitoring of river fluxes (i.e. water, sediment and related contaminants from headwaters to downstream parts), implemented connectivity models with the different global change scenarios, as well as all considered data of environmental relevance from these catchments and related wetlands.