List of freshwater ecoregions (WWF)

This is a list of freshwater ecoregions as compiled by the World Wildlife Fund (WWF). The freshwater ecoregion system is similar to that for terrestrial ecoregions. The Earth's land surface is divided into eight terrestrial biogeographic realms or ecozones, which contain hundreds of smaller ecoregions. Ecoregions are classified into biomes or major habitat types, which have similar climates and vegetation types. The freshwater system is similar, with ecoregions classified into freshwater realms and biomes.