0.2 Spatial gradients in biodiversity  (Page 2/10)

in general terms these are areas that have high levels of endemism (and hence diversity) but which are also experiencing a high rate of loss of habitat. This concept was originally developed for terrestrial ecosystems. A terrestrial biodiversity hotspot is an area that has at least 0.5%, or 1,500 of the worlds ca. 300,000 species of green plants ( Viridiplantae ), and that has lost at least 70% of its primary vegetation ( Myers et al. , 2000 ). Marine biodiversity hotspots have been defined for coral reefs, based on measurements of relative endemism of multiple taxa (species of corals, snails, lobsters, fishes) within a region and the relative level of threat to that region ( Roberts et al. , 2002 )