Assessing Urbanization Dynamics, Land Consumption Patterns, and Their Impacts on the Natural Landscape in Kakamega Central Region, Kenya

Abstract

Abstract

Changes in Land Use and Land Cover (LULC) remain a critical challenge for sustainable urban development, especially in rapidly growing secondary towns and their surroundings. This study aimed to assess the trend in LULC change using geospatial technology, examine urban growth with the Land Consumption Rate (LCR) and Land Absorption Coefficient (LAC), and evaluate the impact of urban development on the natural landscape in Kakamega Central Region from 2003 to 2023. Landsat images from 2003, 2013, and 2023 were utilized to analyze the spatiotemporal changes in five major land cover types in the study area, including built-up, cropland, grassland, forest, and water bodies. A supervised classification method with the machine learning random forest algorithm in Orfeo Toolbox (OTB) was employed for classification. The overall accuracy for all land cover classes exceeded 85% across all years analyzed. Post-classification change analysis revealed varying trends and proportions of LULC. Notably, the built-up area expanded rapidly by 451.4% between 2003 and 2013, and by 130.9% between 2013 and 2023. Throughout the entire study period, cropland increased by 148%, while grassland and water bodies declined by 73.8% and 30%, respectively. Concerning consumption metrics, both LCR and LAC increased during the study period, indicating scattered urban sprawl with implications for the natural landscape. These findings offer foundational insights into the trend of urban growth, providing evidence-based guidance for policymakers to develop policies that promote compact urban growth and conserve the region’s natural landscape.