Use Species Richness when you need to report the number of distinct species observed in a community. Enter Distinct species count using the definitions and units below so the result can be reproduced.

Distinct species count

An integer count or setting greater than or equal to 0.

The published tool contract uses this rule: Report the number of distinct species observed in a community.

Species richness

The calculated species richness.

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

Retain the original Distinct species count values and their units alongside the result. Bootstrap Richness Proxy is useful when you instead need to compute the limited richness proxy Sobs + singletons divided by sample count. A full bootstrap richness estimator requires each species' observed incidence frequency. ACE Bias Corrected provides another view by helping you estimate abundance-based species richness with ACE using the species observed at most ten times, their total individuals, singleton count, and the rare-frequency moment sum i(i-1)f_i. ACE is undefined when every rare individual is a singleton.

• 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.

• ACE Bias Corrected

  Estimate abundance-based species richness with ACE using the species observed at most ten times, their total individuals, singleton count, and the rare-frequency moment sum i(i-1)f_i. ACE is undefined when every rare individual is a singleton.

• Chao1 Bias Corrected

  Compute the documented bias-corrected Chao1 estimate as observed species plus singletons times singletons minus one divided by two times doubletons plus one.