Assessing changes in land use and land cover using remote sensing : a case study of the Umhlanga Ridge sub-place.

Abstract

Land has proven to be a key component in the development of the human population and is viewed as one of the most significant natural resources currently available. This observation brings into question the recent debates surrounding the pressures people tend to impose on the land, which have resulted in transformations in its physical landscape and usage. Mans impact on the earth in terms of the transformations in land cover and land use have rapidly increased over the years. However, as a result of these continuous land transformations, planning and designing sustainable urban development has become challenging due to the additional fact that the available mapped resources of the land can be outdated or of very poor quality. One of the main methods of depicting the significant changes in land cover or land usage is through the utilization of remote sensing and its key application of change detection. Change detection enables the user to analyse the transformations of land use and land cover as it is able to provide consistent coverage at short intervals. One of Durban’s greatest cases of land transformations is change which has occurred in Umhlanga and its surrounding areas. Umhlanga started out as an area of tremendous agricultural value to the South African economy by producing substantial amount of sugar from its vast lands of sugarcane. Over time however, Umhlanga began to develop its coastline and gradually it expanded the transition until it became a central hub of social and urban development. Therefore, this research endeavour focuses on depicting this above mentioned land transformation from fields of sugarcane to the presently expanding area of suburban development in Umhlanga Ridge. The aim of this study is to assess and analyse the land use and land cover changes that have occurred in Umhlanga Ridge using remotely sensed data and to further understand the socio – economic implications of these changes. Utilising the change detection method of image differencing, the remotely sensed data provided by the South African National Space Agency (SANSA) was analysed to identify the changes that have occurred between the years 2006 and 2012. The results yielded from this research endeavour have proved that within Umhlanga and specifically that of Umhlanga Ridge, major land use and land cover transformations have occurred. The most dominant and evident change was found in the larger extent of the Transport and Urban land cover classes by the year 2012. While classes such as the forest and woodland, cultivated Land, grassland and the barren land cover experienced significant drops in their land cover extent, the results generated from the analysis showed that most of these land covers were taken over by the development of urban features. Furthermore, this study reported profound socio – economic implications which occurred due to widespread land use and land cover changes. While many implications were documented, one of the main implications of this nature was found to be the significant number of employment opportunities that became available as a result of the expanding urban landscape. As the urban landscape of this area is continuing to change and expand, it is important to highlight that as a direct consequence of this action, the extent of the naturally occurring environment is being depleted. Therefore, with the urban development now being Umhlanga’s dominant land cover class, additional and supporting data has revealed that the Tongaat Hulett Company and Development sector strives to maintain a balanced with its ecological surroundings by ensuring that suitable sustainable methods are used in the development process and in the maintenance of the area. To conclude, in accordance to the research produced from this study, it is evident that the urban development in Umhlanga and Umhlanga Ridge has grown tremendously and will continue to expand at a steady rate in the future, with the intention of meeting the demands of the area’s visiting tourists and permanent residents. However, while these continuous land use and land cover changes are taking place and expanding, it is imperative that a balanced relationship between man and nature be taken into consideration.