Assessment of Land Use and Land Cover Change Dynamics and Drivers in Mbagathi River Catchment in Kajiado County, Kenya

Abstract

Land use and land cover change through human modifications has brought great changes at global, regional and local levels part of which poses a threat to human and environmental systems. Monitoring of these changes is necessary to ensure the sustainability of terrestrial ecosystems such as the Mbagathi River catchment. The study sought to determine the land use and land cover changes and drivers in the Mbagathi River catchment for the period 1990-2020. This was achieved by the classification of multitemporal Landsat imageries of 1990, 2000, 2010 and 2020 using the Google Earth Engine web platform. The study established four main land use/cover classes including forest, grassland, urban and bare ground. The results of the classification and analysis process established that forest cover reduced from 32% to 14%, grassland reduced from 53% to 30%, bare ground increased from 10% to 38% and urban land cover increased from 4% to 17%. This revealed that urban and bare ground land covers increased at the expense of forest and grassland covers. Multitemporal and spatial assessment of settlement observed that more settlements emerged around the key urban centres namely Kiserian, Ongata Rongai, Ngong, Mlolongo and Tuala. Further analysis within a 3 Km radius of the towns revealed that urban area increased by 11% and 19% for Tuala and Kiserian respectively while in Ongata Rongai and Ngong, the urban area increased by 20% and 23% respectively.