Total species diversity, or species richness, across all communities within a geographic area is referred to as diversity.

gamma diversity

Explanation:

Gamma diversity

The name was given by R. H. Whittaker ,

Gamma diversity = the total species diversity in the landscape .

Beta diversity = the differentiation among the habitats .

Alpha diversity = the mean species diversity in sites , or at local scale .

The product of alpha diversity and beta diversity together gives the gamma diversity .

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