Annual production fraction of aboveground biomass in relation to plant shrubbiness in savanna

Abstract

A new means of estimating the annual production fraction of aboveground biomass of woody plants along a full shrub-tree continuum in savanna is presented. A measure of shrubbiness was found to be quantitatively definable over a shrub-tree continuum, to closely relate to the annual production fraction and to provide a single criterion for defining shrub and tree forms in South African savanna vegetation. It is proposed that in South African savanna, shrubs be defined as perennial woody plants with an annual production fraction of greater than 10% and trees with that less than or equal to 10%.