Changes to the vegetation of the mid‐Fish River valley, Eastern Cape, South Africa, in response to land‐use, as revealed by a direct gradient analysis

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Abstract
Degradation of natural rangeland is a serious problem throughout southern Africa. It has been suggested that incorrect grazing management practices have resulted in a decrease in the production potential of rangelands. In order to explore the nature and extent of degradation at the landscape scale, we selected a study site where a range of land‐use and rangeland management practices could be studied in parallel. The mid‐Fish River valley consists of three markedly different units of land management, namely, commercial rangelands, communal rangelands and nature conservation areas. Using a direct gradient analysis approach, the vegetation of the study area was classified into homogenous units. A shift in the vegetation composition in response to different land‐use treatments was investigated. The results of the classification showed three major plant communities present in the study area, namely, Short Succulent Thicket, Medium Succulent Thicket and Mesic Bushclump Savanna. The results revealed a definite grazing gradient within the study area. It showed that an increase in grazing intensity resulted in a transformation from vegetation synonymous to a mesic environment towards that found in an arid environment. As grazing pressure increased there was a decrease in palatable grasses, succulents and herbaceous species and an increase in dwarf karroid shrubs.