Disturbance-driven alteration of patch connectivity determines local biodiversity recovery within metacommunities.

Abstract

Understanding the capacity of ecological systems to withstand and recover from disturbances is a major challenge for ecological research in the context of environmental changes. Past research has mostly focused on the local effects of disturbances on biodiversity recovery, while alterations of inter-patch connectivity induced by disturbances have received comparatively less attention. Here, we investigated the effect of disturbances on local biodiversity recovery within metacommunities. Our specific focus was on drying river networks, which are characterised by a high variability of patch connectivity. We found marked variations of local biodiversity recovery among sites and among groups of organisms with contrasting dispersal modes, which were explained by the amount of patch connectivity loss due to drying events. Local communities of flying organisms recovered more efficiently from drying events than organisms with strictly aquatic dispersal due to the capacity of the former group to overcome hydrological connectivity loss. As a general rule, loss of patch connectivity decreases community recovery, regardless of patch location in the river network, dispersal mode or drying spatial extent. The relationship between patch connectivity loss and community recovery we found in river networks is general and applicable to any spatial network with a high variability of patch connectivity.