Spatio-Temporal Dynamics of Land Use and Ecological Degradation in the Nduh Nkemlepè Watershed, Bamboutos Mountains, Cameroon

Abstract

Land use and land cover change (LULCC) is a major driver of environmental transformation, particularly in fragile mountainous ecosystems where increasing human pressures accelerate ecological degradation. In the Bamboutos Mountains of Cameroon, the Nduh Nkemlepè watershed has experienced significant landscape changes, raising concerns about the sustainability of natural resources. This study aims to analyse the spatio-temporal dynamics of land use and assess their implications for ecological degradation between 2000 and 2024. An analytical and diachronic methodological approach was adopted, based on cartographic analysis that integrated remote sensing and Geographic Information Systems (GIS). Satellite images from Landsat ETM and Land Change Modeler, with a spatial resolution of 30 m, were used and projected to WGS 84, UTM Zone 32N. Image processing involved mosaicking, enhancement, geometric correction, and supervised classification using the Maximum Likelihood method based on the LCCS system. Field surveys were conducted to validate classification accuracy. Spatial dynamics were assessed through statistical analysis of land use changes, including rates of progression, regression, and stability, using the formula: Tv (%) = [(S2/S1) − 1] × 100. The results reveal a substantial transformation of the watershed landscape, characterised by a marked expansion of cultivated land (from 25.15% in 2000 to 60.75% in 2024) and built-up areas (from 2.25% to 10.49%), alongside a sharp decline in Eucalyptus gallery forests and grasslands. Bare soils and rocky outcrops also increased, indicating progressive land degradation. The ecological index decreased from 0.6897 in 2000 to 0.4548 in 2024, reflecting deterioration in environmental quality. These findings highlight increasing anthropogenic pressure associated with ecosystem degradation, biodiversity loss, and reduced ecosystem services. The study recommends adopting sustainable land management practices, including agroforestry, improved land-use planning, ecological restoration, and strengthened institutional governance, to support long-term environmental sustainability.