The colonization process in new creation Mediterranean salt marsh lagoons is influenced by hydrological fluctuations characterised by flooding-confinement periods. This pattern has direct effects on water characteristics (such as nutrient concentration), but it also effects the connectivity structure between lagoons impacting main metacommunity dynamics. Unfortunately, these ecosystems have suffered transformations due to urbanization process that has contributed to its degradation. This is the case of La Pletera salt marshes, located in the NE of Catalonia, in where a recovery and restoration European LIFE project (LIFE13 NAT/ES/001001) that included the restoration of existing lagoons and the creation of new ones has been done. In this study, we analysed the structure of aquatic macrofauna community of these new created lagoons just after its creation and five years after its creation with the aim of assessing the colonization assembly process. Our results showed a fast colonization of the species with active dispersion since they dominated the communities right after lagoon creation (Diptera). In contrast, species with passive dispersion (Gastropoda and Amphipoda) that have a lower dispersive capacity were dominant at the last sampling survey, 5 years after creation. This could be explained by flooding periods that connect all wetland waterbodies favouring the arrival of both, active and passive dispersers. Moreover, we observed an increase in the abundance and biomass of taxa with lower dispersion capacity but without affecting the overall community richness values
