"Assessments of global patterns of climate change forecast a general increase of temperature and changes in precipitation. It seems that floods and droughts would become more severe and frequent across Europe, thus increasing the proportion of rivers with mediterranean characteristics in actually temperate areas. Therefore, climate change and increasing water demand will inevitably expand river drying in time and space. Hydrological effects include flow interruptions, loss of hydrological connectivity between river compartments and increased water residence times in extended sections of river networks. It has generated a renewed and urgent need to better understand the ecological structure and function of temporary rivers. It is recognised that the interruption of superficial flow plays an essential role in the macroinvertebrate aquatic communities, however few studies are focused in the influence of a gradient of flow intermittence on richness, density and traits of macroinvertebrate communities within temporary streams. Moreover, the importance of the dry river-beds by maintaing the diversity of aquatic and terrestrial assemblages, regulate the transfer and transformation of energy and materials, and define the resilience of the system, has been highlighted recently.The general objective of this research is to find out as the duration, extent and severity of the dry period will control both aquatic and terrestrial assemblages, to predict the effect of climate change in European rivers.The main specific objectives are: i) to analysis changes in community structure and composition, and biological traits of macroinvertebrate assemblages along a gradient of flow intermittence in temporary rivers, ii) to study the effects of different mesohabitats in macroinvertebrate communities, and iii) to investigate the effect of the expansion dry river bed period on terrestrial invertebrate assemblages and the throphic linkage between aquatic and terrestrial organisms."