An attempt to separate out climatic and man-induced causes of range degradation in Botswana using Landsat MSS imagery

• Published in: Geocarto international 1990-12, Vol.5 (4), p.41-56
• Main Authors: Ringrose, Susan, Matheson, Wilma, Tempest, Faith, Boyle, Timothy
• Format: Article
• Language: English
• ISSN: 1010-6049; 1752-0762
• DOI: 10.1080/10106049009354281

Changes in natural vegetation cover comprising the Kalahari rangeland were undertaken using Landsat MSS imagery over a period of above average rainfall (1972-1982) and a period of drought (1982-1986). This and ancillary data were collected to determine whether changes in the range were related primarily to rainfall events or to man-induced effects. Data from different orbits were made compatible digitally. Dark area subtraction was a problem because deep shadow and water were lacking in the Kalahari landscape. Eleven land-use/land cover classes were derived for the 1984 base year. Additional signatures had to be obtained for the later drought years because of extreme increases in brightness. Broadly the south-eastern Kalahari was divided into an interior, relatively uninhabited homogeneous area and a more diverse area containing fossil valleys and pans. Changes in vegetation cover in the interior appeared to be more related to rainfall events than anthropogenic factors. Changes in the fossil valley vegetation cover appeared to be more related to rainfall events during the period of above average rainfall and more related to cattle and smallstock densities during the drought period.