Key long term patterns for the management and Conservation of temporary Mediterranean streams: a case study of the Pardiela river, southern Portugal (Guadiana catchment)

Abstract

Temporary waters are widespread in the Mediterranean, as well as in many other semi-arid regions worldwide. They are defined as those that are normally dry, at least during an extended part of the year (the summer in Mediterranean regions). Most streams in the Mediterranean are temporary that expand during the winter period and contract and fragment during spring and summer periods. Understanding and predicting the complex interactions between hydrology and stream dynamics form a basis to fulfill the requirements of the Water Framework Directive (WFD). Despite the importance of temporary waters in the Mediterranean region, the WFD does not appear to attach them the appropriate importance. Even the term temporary waters cannot be found in the WFD text, which excludes rivers that have no permanent natural flow. However, the inclusion of all catchments with areas greater than 10 km2 appears implicitly to include many temporary water bodies. Taken into account this issue, the project “Conservation and rehabilitation strategies for temporary Mediterranean river corridors: a case study on Pardiela basin, southern Portugal (Guadiana basin)" is being carried out, with the collaboration of researchers from different scientific areas. The applied methodologies were designed in order to study the temporal interactions among different ecological components: climate, morphology of stream corridor, hydrology, also considering the available information from the last 50/70 years. The obtained results were integrated in the model-MOHID River Network, an integrant part of the basin model MOHID Land that was coupled to the SWAT model. The final model simulations were combined in rehabilitations and conservation strategies for a sustainable management of temporary Mediterranean streams, taking into account the temporal evolution observed in Pardiela basin.