Fragile calculus: Climate, political economy and vegetation change in the semi-arid Karoo, South Africa

A range of methodologies comprising Remote Sensing, Geographical Information Systems, modeling, published socio-economic data and in-depth ethnographic field interviews are used to identify proximate and underlying anthropogenic dimensions of vegetation cover modification in the eastern semi-arid Karoo, South Africa. A 14 year monthly time series of Normalized Difference Vegetation Index data at the 1 kilometer resolution was extracted, corrected and detrended for rainfall effects, using an interpolated time series of monthly rainfall data for the same spatial extents. Change detection information from the detrended vegetation series was compiled for each of 73 land management units in and around the Graaff Reinet magisterial district in the eastern Karoo. Extensive in-depth interviews were undertaken with each of the managers, gathering data used to determine proximate land-use strategies (such as stocking system and stocking intensity), and underlying socio-economic trends (such as debt level and security of tenure) which are then linked to trends in vegetation change occurring on the farm, and to the location of the management unit within the transforming South African political economy at the regional and national scales. Study results show exciting past linkages between stocking system choice and manager debt level; and current linkages with property acquisition status and affluence. A small but significant relationship between stocking system choice and the detrended vegetation time series for each management unit is further evident. Findings may inform policy and local guidelines concerning rangeland management and land-use allocation, as well as providing new challenges to meaningful work in political ecology, environmental change and climate impact assessment.