Scientific African (Jul 2023)
Land use and land cover changes along the Boteti-Thamalakane River system in Ngamiland District, Botswana
Abstract
Analysis of the dynamics of land use and land cover change (LULCC) along rivers that supply water to settlements provides crucial information to decision-makers; it offers information for planners and water supply authorities on water management issues in general. The paper analyzed LULCC along Boteti and Thamalakane rivers and predicted the probable LULCC for the year 2050 using the artificial neural network (ANN) of the module for land use evaluation (MOLUCE) within the QGIS 2.9 software. Adopting a supervised classification method, the Maximum Likelihood Classification (MLC) algorithm was used to classify the study area into five LULC categories. Findings show an increase in a built-up area (46.5%), barren land (90.1%) and a decrease in shrubs/trees (67.4%), water/waterlogged area (48%) and hydrophytes (39.3%) between 1990 and 2020. Using 2020 as the baseline, the ANN modelling approach predicted an increase in the built-up area and a continued shrinking of water and shrubs/trees spatial coverage in the next 30 years. Findings also reveal the presence of building constructions within less than 500 m from the river channel and/or flood plains. While a strict monitoring of the construction works along the riverbank needs to be constantly carried out, the paper also recommends the creation of a buffer zone of 500 m along the rivers where construction activities are prohibited.
