The relation between canopy spread cover and the aboveground available phytomass of Nama Karoo subshrubs and grasses

Abstract

The canopy spread cover of Karoo bushes and grasses in the Nama Karoo was measured and related to the aboveground phytomass available to the grazing animal. A correlation coefficient of r = 0.7456, calculated for Karoo bushes, indicates that this method can be used to non-destructively estimate available phytomass. This in turn can be used for the prediction of current grazing capacity in areas where Karoo bushes are dominant in the vegetation. In the case of the Karoo grasses, a rather loose definition and interpretation of the canopy spread cover, led to a low correlation coefficient, r = 0.5662. This renders the present method largely unsuited for available phytomass estimations to be used in further predictions of grazing capacity in the mountainous areas where the studied grasses are dominant in the vegetation. In the more arid areas, however, the method can be used to advantage.


Keywords: veld type; grazing capacities


African Journal of Range & Forage Science 2001, 18(2&3): 143-146