Monitoring and modelling open savannas using multisource information: analyses of Kalahari studies

In the Kalahari of Botswana. as in many other open savannas, the main ecological change following cattle-based agricultural intensification is one of grass removal and bush encroachment. Changes to vegetation communities in Kalahari rangelands have been expressed in terms of a state-and-transition model. However, there remain uncertainties as to the mechanisms and conditions for ecological change. In part, this is due to previous (inadequate) spatial and temporal scales of data collection. This paper describes the results of ongoing ecological studies in the Makoba ranches and analyses the contribution that fine-scale ground-based surveys and interpretation of Earth observation data can make to reducing uncertainties in state-and-transition models. This detailed case study provides a mechanism for evaluating the role of multi-source information for monitoring and modelling open savannas.