Recovery of temporary pond alpha and beta diversity after wildfire disturbance: the role of dispersal and recolonization processes.

Wildfires are considered a world-wide disturbance which is currently being fostered by human-induced global changes. Their frequency and intensity are expected to increase in the near future in regions such as the Mediterranean basin. While terrestrial systems responses to wildfire have been thoroughly studied, aquatic systems such as temporary ponds have received less attention. Furthermore, previous works have focused on wildfire impacts in aquatics systems from a more functional and trait-based approach, but such disturbances can also impact these systems diversity at the local and regional level. In this work, we assess wildfire impacts in alpha and beta diversity of Mediterranean temporary ponds, analysing samples of pond macrofauna from before and after a wildfire that partially burned a set of temporary ponds. The wildfire did not change alpha-diversity patterns but differences in beta-diversity were observed when considering species abundance. Species with greater contribution to beta-diversity were more represented in Unburned ponds after the wildfire. These changes in species presence during the beginning of the hydroperiod increased Burned ponds regional differences (i.e., replacement increase). However, these alterations disappeared towards the middle and the end of the hydroperiod. Overall, we reported a fast recovery after the wildfire, tightly linked to a rapid recolonization that increased pond similarities. Landscape structure and ponds seasonal succession would have increased these systems resilience, but these key features against wildfire might become compromised due to global change scenarios (i.e., rise in wildfire regimes and habitat loss), representing a potential future threat to these highly diverse habitats.