A non-destructive method to estimate biomass in arid environments: A comment on Flombaum and Sala (2007)

Numerous ecological studies in grasslands and shrublands have used plant cover as a surrogate of aboveground net primary production (ANPP), biomass or biovolume. Regression equations between biomass and plant cover involve taking into account a wide range of vegetation cover. This comment assesses the consequences for biomass estimations of the method presented by Flombaum and Sala [Flombaum, P., Sala, O.E., 2007. A non-destructive and rapid method to estimate biomass and aboveground net primary production in arid environments. Journal of Arid Environments 69, 352–358.], which consists in removing portions of individuals to achieve the desired plant cover estimation. We found that alteration of architecture of individuals could lead to an overestimation of biomass by a factor ranging from 1.05 to 3.16, depending on the extent of the reduction of the plant cover.