Diversity is nothing relates to the number of species which is found in the community. Richness of species is thus considered as measurement of biodiversity. However, many methods have been proposed for calculation of biodiversity. Species diversity in different geographical scales are referred in the following manner:
1. Alpha Diversity:
This deals with the number of species in a single community. This diversity was come closest to the popular concept of species richness and thus can be used to compare the number of species in different types of ecosystem.
2. Beta Diversity:
This deals with the degree to which species composition changes due to environmental factors. Beta diversity is high in case the composition of communities changes at successively higher elevations on a slope of the mountain. However, beta diversity is low of the same species occupy the whole mountain side.
3. Gamma Diversity:
This deals with larger geographical scale and is defined as the rate at when additional species are encountered with the geographical replacements within a habitat type in different localities.