LN Kiguli
Departrnent of Botany, Rhodes University, P.O. Box 94, Grahamstown, 6140 Republic of South Africa
AR Palmer
ARC - Range & Forage Institute, P.O. Box 101, Grahamstown, 6140 Republic of South Africa
AM Avis
Departrnent of Botany, Rhodes University, P.O. Box 94, Grahamstown, 6140 Republic of South Africa
Abstract
Analysis of a Landsat TM image from a rangeland near Peddie, Eastern Cape, revealed differences in two vegetation indices (normalised difference vegetation index, NDVI, and moving standard deviation index, MSDI) between communal and commercial rangeland. It was suggested that the difference in the MSDI reflected differences in rangeland condition. To assess whether or not any differences could be detected in the field, vegetation parameters were recorded (cover, species composition) along ten, paired 20m transects. Based on species forage factors for commercial livestock production, the commercial grassland was in a significantly better condition than the communal land. The commercial farmland had a higher occurrence of palatable species while the communal land was richer in
non-palatable species. A TWINSPAN classification and the NDVI and MSDI values confirmed the marked difference between the communal and the commercial land. Both the vegetative field survey data and the satellite imagery showed that the communal land was transformed in comparison to the commercial land, and this difference can be attributed to differences in land-use.
Keywords: Degradation, grassland, palatability
African Journal of Range and Forage Science 16(2&3): 89–95