Functional diversity index (FDvar)

FDvar measures the variance in the log-transformed attribute values of the species present at a site, weighted by relative abundances.


Mason Norman W.H., MacGillivray Kit, Steel John B., and Wilson J. Bastow1

Published in

Journal of Vegetation Science 14, 2003, pp 571-578.


From 0 to 1


It is designed to work with one character at a time.


Unaffected by whether two sibling (and functionally equivalent) species in a genus are combined or kept separate, so long as an additive measure of abundance is used. It is not affected by the number of species .


This index is analogous to the evenness index Evar of Smith & Wilson (1996)

R Package

R Package description

Studies that used this index


Smith, B. & Wilson, J.B. 1996. A consumer’s guide to evenness indices. Oikos 76: 70-82.

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