The International Journal Of Engineering And Science (IJES) ||Volume|| 2 ||Issue|| 10 ||Pages|| 66-73 ||2013|| ISSN (e): 2319 – 1813 ISSN (p): 2319 – 1805 www.theijes.com The IJES Page 66 Remote Sensing for Mapping Land-Use/Cover Changes and Urban Sprawl in Sekondi-Takoradi, Western Region of Ghana M. S. Aduah, P. E. Baffoe Department of Geomatics Engineering, University of Mines and Technology, P. O. Box 237, Tarkwa, Ghana ------------------------------------------------------ABSTRACT---------------------------------------------------- Land use/land cover influences a variety of processes on the Earth surface which also generate feedback effects on the natural environment, economic and social systems. Poorly managed changes in urban areas have resulted in many catastrophic consequences such as floods, landslides, droughts etc. The Landsat satellite system has long term data archives and can be used to assess the land cover changes in the landscape to provide information to support future urban planning. In this paper Landsat images were used to map the land use/land cover changes in the city of Sekondi-Takoradi in the Western region of Ghana from 1988 to 2011 through a change detection process. The post-classification method of change detection was used and the accuracies achieved were high. The analysis showed that a large portion of the city and its surrounding areas has been converted from natural surfaces to impervious surfaces. Also it was observed that precipitation has reduced considerably during the period and high temperatures have been observed. A model developed between land use change and time have showed that in the next 50 years if the trend of land use change continues, there will be complete removal of natural surfaces. These could lead to increased incidence and severity of flash floods and droughts. Therefore the data produced in this study can be used to guide effective urban planning to mitigate the combined effects of land use changes due to urbanisation and climate change. This study demonstrates the critical role remote sensing can play in the developing world in terms of providing data for planning since many countries do not have the resources to map their territories regularly through conventional means. Key words: change detection, land use/land cover, Landsat, remote sensing, Sekondi-Takoradi --------------------------------------------------------------------------------------------------------------------------------------- Date of Submission: 01 st , October, 2013 Date of Acceptance: 30 th , October, 2013 --------------------------------------------------------------------------------------------------------------------------------------- I. INTRODUCTION Land use/land cover (LULC) influences a variety of processes on the Earth surface. These processes also generate feedback effects on the natural environment, economic and social systems. LULC is pervasive in urbanised environments worldwide and reflects a society’s interactions with the physical environment (Campbell, 2002). Hence poorly managed changes in urban areas have the potential to result in many social, economic and environmental catastrophes such as floods, landslides, droughts, lack of safe drinking water and loss of crop productivity etc. It is imperative therefore that urban land use is planned properly to ensure that sustainable social, economic and environmental goals are achieved. To achieve these objectives it is important to map the existing LULC of the urban areas. It is only then that it will be possible to analyse which land use best suits a particular land cover considering all necessary variables. For example, it will not make economic sense to build low cost estates on rich agricultural lands and it will not make environmental sense to construct certain industries in riparian habitats. The overall objective of ensuring that the urban land use is not mixed is to ensure sustainable utilization of the natural resources. Urban LULC occurs mostly by the removal of vegetation through anthropogenic activities such as construction of housing estates, road construction, agriculture and livestock raising, forest harvesting and mining etc. These causes are influenced by population increase, government policy and economic development. In some places the occurrence of major floods can also alter the land cover though the floods are also influenced by LULC. Other causes of LULC changes include bushfires and climatic changes (Aduah et al., 2012). LULC changes in urban areas create impervious and non-evaporative surfaces. The consequences include increases in storm run-off, river discharge rates and floods in low lying areas. Others include increased soil erosion and alteration of the surface energy balance resulting in increased land surface temperatures and urban heat islands (Aduah et al., 2012). These changes also cause high evaporation rates and decreased productivity of soils and crops. Over long period of time urban land cover turning into impervious area will reduce the ground water recharge and pollution of water bodies due to non-point source pollution and sedimentation. Pollution and sedimentation of water bodies will reduce wetland habitats and affect the flora and fauna hence reducing biodiversity. Consequently water treatment for the urban areas would be expensive and supplies would be limited.