Use Margalef Richness when you need to compute the Margalef richness index from species count and total individuals. Enter Species count and Total individuals using the definitions and units below so the result can be reproduced.

Species count

An integer count or setting greater than or equal to 1, expressed in species.

Total individuals

An integer count or setting, expressed in individuals.

The published tool contract uses this rule: Compute the Margalef richness index from species count and total individuals.^[1]

Margalef richness index

The calculated margalef richness index.

The calculation does not propagate measurement uncertainty, sampling error, or biological and chemical variability.

Retain the original Species count and Total individuals values and their units alongside the result. Menhinick Richness is useful when you instead need to compute the Menhinick richness index as species count divided by the square root of individual count. Bootstrap Richness Proxy provides another view by helping you compute the limited richness proxy Sobs + singletons divided by sample count. A full bootstrap richness estimator requires each species' observed incidence frequency.

• Menhinick Richness

  Compute the Menhinick richness index as species count divided by the square root of individual count.

• Bootstrap Richness Proxy

  Compute the limited richness proxy Sobs + singletons divided by sample count. A full bootstrap richness estimator requires each species' observed incidence frequency.

• Rarefied Richness

  Estimate rarefied species richness with the documented linear form sTotal x m / n for a subsample of m individuals drawn from n.