Pattern and process in a semi-arid grassveld in Rhodesia.

Abstract

The study was conducted on the grass component of Redsoil veld at four sites in the vicinity of Bulawayo, situated in the medium rainfall (400 to 700 mm) zone of Rhodesia. A pattern in which the veld consists of a mosaic of scattered "degraded patches" of varying shapes and sizes set in a matrix of "sound veld" is demonstrated. The distribution of selected grass species within this mosaic is shown. Rainfall induced changes in yield relationships and species distributions within this pattern were followed over four growing seasons. The pattern is shown to be related to variations in the infiltration capacity of the surface soils, and causative mechanisms are postulated.

Keywords: bulawayo; grass; grasses; infiltration; rainfall; redsoil; relationships; rhodesia; semi-arid grassveld; soils; species distribution; variation; veld; yield; zimbabwe