`n Morfometriese ondersoek na landskapontwikkeling in die Sentraal-Vrystaat: `n toepassing met behulp van `n geografiese inligtingstelsel

[摘要] English: In the thesis, a geographic information system is used to investigate the morphometry and active geomorphic processes in a semi-arid catchment area. The construction of a digital terrain model from published sources is elucidated and an erosion model is used to explain the spatial distribution of drainage basins in the study area The study was conducted in the Modder river catchment in the central Free State. The study area was chosen as the result of tectonic stability which should lessen the impact of endogenic processes in the current form of the landscape In the first part of the study, a set of morphometric parameters were chosen to represent the current form of the landscape as accurately as possible. Several process parameters were also identified to quantify the active erosion processes in the area. To explain the relationships between form and process, a working erosion model is used. This model was calibrated by using current environmental conditions. In the second part of the thesis, a digital terrain model of the study area was constructed. Several techniques for the construction were evaluated and a method for stream and pan burning was developed. A geographic information system were used to collect data sets from different published sources and to combine it into a single database. The GIS was also used to extract the applicable parameters from the database. The last part of the study was devoted to the analysis of the data and the creation of a development model for the catchment. Several statistical techniques were used to classify the parameters and to group the drainage basins. The relationships between the parameters were investigated and quantified. From the study it was clear that a relationship exists between form and process in the Modder river catchment area and that geographic information technology can be used with success in the study of landforms. The methodology developed for the study as well as the data generated might be useful for the management of the catchment in various ways.

[发布机构] University of the Free State