Beta diversity

[citation needed] Whittaker proposed several ways of quantifying differentiation, and subsequent generations of ecologists have invented more.

Due to these two reasons, a new way of measuring species turnover, coined Zeta diversity (ζ-diversity),[12] has been proposed and used to connect all existing incidence-based biodiversity patterns.

Because the limits among local sites and landscapes are diffuse and to some degree subjective, it has been proposed that gamma diversity can be quantified for any inventory dataset and that alpha and beta diversity can be quantified whenever the dataset is divided into subunits.

[2] It is calculated as βW = (γ - α)/α = γ/α - 1 When there are two subunits, and presence-absence data are used, this equals the one-complement of the Sørensen similarity index.

[2] It is calculated as βP = (γ - α)/γ = 1 - α/γ When there are two subunits, and presence-absence data are used, this measure as ranged to the interval [0, 1] equals the one-complement of the Jaccard similarity index.

For example, niche compression hypothesis predicted higher β-diversity at lower latitudes.

The results of these two studies were completely different from the results of a recent quantitative synthesis,[26] which showed that β-diversity in primary forests were similar to β-diversity in all types of human-modified local sites (secondary forests, plantations, pasture and urban).

Sreekar et al.[19] suggested that most of these inconsistencies were due to the differences in grain size and/or spatial extent among studies.

Major diversification events in the geologic past were associated with shifts in the relative contributions of alpha- and beta-diversity (diversity partitioning).