Ecoregions are large areas of land or water containing geographically distinct assemblages of natural communities sharing species, ecological dynamics, and environmental conditions. Used in ecological research and conservation, ecoregions need to capture and describe communities well.
Integrating maps of ecoregions with data on environmental conditions, biodiversity and species traits, this study aimed to quantify the descriptive powers of ecoregions. Using GBIF-mediated occurrences of nearly all organisms, the authors modelled abiotic and biotic predictors of ecoregion distinctness.
In their results, they find evidence that ecoregion distinctness is best predicted by temperature and seasonality (presence of variations occurring at specific, regular intervals, i.e., seasons). With high average temperatures and rainfall combined with low seasonality, tropical ecoregions more strongly differentiate communities. Also, ecoregions are most distinct in regions with steeper slopes.
From a biotic perspective, ecoregion distinctiveness is more pronounced for reptiles and amphibians than mammals or birds and, in general, more pronounced for smaller-bodied species.
Overall, the study shows that ecoregions, while a powerful tool for conservation planning, do not necessarily describe communities uniformly across regions or taxa.