The freshwater ecoregion map encompasses 426 units, whose boundaries generally - though not always - correspond with those of watersheds (also known as drainage basins or catchments).
Within individual ecoregions there will be turnover of species, such as when moving up or down a river system, but taken as a whole an ecoregion will typically have a distinct evolutionary history and/or ecological processes.
...has been brought together for each ecoregion to include richness and endemism numbers for freshwater fish, amphibians, turtles, and crocodiles.
...include examination of land cover conversion, the presence of large cities, urban land cover, area equipped for irrigation, human footprint, and water stress.
Information describing freshwater species has been dispersed and difficult to access, if it exists at all. This project begins to fill the gap, providing a basic level of information on freshwater biogeography and biodiversity that complements parallel terrestrial and marine efforts.
Therefore at global and regional scales the ecoregion map can be used to distinguish distinct units of freshwater biodiversity to be represented in conservation efforts.