Soils and terrain
The soils in the study area could be classified as Luvisols (mainly found in the plains or lacustrine system); the Arenosols (the former shorelines like Gidikwe) and the Fluvisols which are mainly along the coarse/floodplains of the Boteti River. The plains zone is typified by several pans of varying sizes - and these have varying salt levels; hence calcic, sodic and saline soils e.g. solonchaks, have been identified in the area. The lacustrine (pan dominated and plains) area has sparse grass vegetation and it is this area which tends to be dominated by the windy dry season erosion. It is the finer particles of clay and silt, in the extensive bare areas which are most prone to the dust erosion. Some of the source regions, other than pans and bare plains, are cattle tracks. These tracks are made by cattle as they move from the grazing areas (mainly the ridge area) to the water points e.g. the river, wells and boreholes which are located within the plains. However not all the places are dominated by wind erosion e.g. the ridges, northern and eastern plains are all well covered with vegetation, mainly grass but may even include shrubs and trees. The western plains and areas with boreholes and wells (livestock trampling and grazing) are the main wind erosion zones. Some of the resultant wind erosion leads to coppice mounds or nebkhas - which are sand dunes which accumulate around bushes (vegetative barriers). Typically, wind speeds in the area range between 7-8km/hr, but some gusts reaching 40km/hr have been reported. Fluvial erosion is limited to pan margins as little scarps as well as some portions of the Boteti River where the banks retain a certain height above the river bed. Thus the fluvial erosion is predominantly localised - and does not cover the breadth of the extensive plains or the sand ridges.
