Disturbance and topography shape the capacity of microrefugia to support unique biodiversity
Microrefugia play a key role in facilitating the persistence of biodiversity during climate change, making them important habitats for future conservation planning. Many microrefugia occur in topographically complex landscapes shaped by various disturbances, but we know little about how the combined effect of topography and disturbance impacts the capacity of refugia to support biodiversity under future climate change. To investigate this, we inventoried taxonomic richness across four biological groups (soil microbiota, vascular plants, terrestrial snails, and ants) and air and soil environmental conditions in various microhabitats (south-facing slopes, north-facing slopes, and bottoms) of karst dolines, which are known contemporary microrefugia. Relationships between indicators of ecosystem disturbances (historical logging and the presence of treefall gaps) and species richness differed, depending on the biological group and microhabitat. While most biological groups seemingly recovered within 50 years following logging, plants did not. Plants were also the only group that displayed a significant response to the presence of small canopy gaps at doline bottoms, which promoted the occurrence of specific plant species. All biological groups displayed some response to topographic microhabitats, though those differed among taxa. We conclude that the direction and magnitude of the effects of disturbance and topography are strongly taxon-specific, possibly related to species-specific responses to microenvironmental conditions. Therefore, disturbance history is an important consideration when identifying refugia for climate change management.