Land Capability Evaluation Using Remote Sensing and GIS in Communal Areas of North West Province, South Africa

Abstract

This study sought to develop a framework as a tool for land capability evaluation using remote sensing, GIS and geostatistical techniques for communal areas, where the results can be duplicated in other geographical areas with similar biophysical conditions. The relationships and interactions between components and parameters that are necessary for analysing the capability of agricultural land were investigated for an effective management system. The parameters taken into consideration were biophysical environment (soil texture, organic matter content, soil depth, etc.), socio-economic and policy. The primary data were obtained from climatic data and soil samples collected from depths 0- 100 cm; the secondary information were acquired from the remotely sensed data (SPOT 5 HRG), toposheet, ancillary data, and agricultural statistics. Crop requirement information of three different crops that were selected as representative of summer crops in North West province, namely maize, sorghum and sunflower were compared with the land resources parameters available in the four sites. The thematic layers of the land resources were then overlaid using a GIS to select areas that satisfy the crop requirements. The resulting maps showed that the study areas have moderate to very high capability for all crops and that the land capability assessment developed, is adaptable, flexible and applicable in arid and semiarid environments. It was concluded that Agricultural Impact Assessments (AIA) as part of land capability should be integrated in land reform policy prior to acquisition of land to beneficiaries. Land with high degree of agricultural capability (based on soil properties, terrain characteristics and present land use) should be identified to produce economical yields under specific uses over a long period of time and without degradation to the land.