Gamma diversity

Gamma diversity (γ-diversity) is a measure of biodiversity

Biodiversity

Biodiversity is the variation of life forms within a given ecosystem, biome, or for the entire Earth. Biodiversity is often used as a measure of the health of biological systems...

. It refers to the total species richness over a large area or region. It is the product of the α diversity of component ecosystems and the β diversity between component ecosystems.

According to Whittaker (1972), gamma diversity is the richness in species of a range of habitats in a geographic area (e.g.,a landscape, an island) and it is consequent on the alpha diversity of the individual communities and the range of differentiation or beta diversity among them.

Gamma diversity (γ-diversity) is a measure of biodiversity

Biodiversity

Biodiversity is the variation of life forms within a given ecosystem, biome, or for the entire Earth. Biodiversity is often used as a measure of the health of biological systems...

. It refers to the total species richness over a large area or region. It is the product of the α diversity of component ecosystems and the β diversity between component ecosystems.

According to Whittaker (1972), gamma diversity is the richness in species of a range of habitats in a geographic area (e.g.,a landscape, an island) and it is consequent on the alpha diversity of the individual communities and the range of differentiation or beta diversity among them. Like alpha diversity, it is a quality which simply has magnitude, not direction and can be represented by a single number (a scalar).

Gamma diversity can be expressed in terms of the species richness of component communities as follows:
where, S₁= the total number of species recorded in the first community, S₂= the total number of species recorded in the second community, and c= the number of species common to both communities.
The internal relationship between alpha, beta and gamma diversity can be represented as