Analysis of Landuse/Landcover Change in Damaturu Town of Yobe State, Nigeria

Landuse/landcover change detection is an essential process in monitoring and managing natural resources and urban development because it provides quantitative analysis of the spatial pattern, distribution, and variation of the physical and cultural landscape features. Damaturu town became the capital of Yobe State when it was created in 1991. Since then, Damaturu has been experiencing rapid changes in the landuse/landcover types due to urban expansion, economic development, and social transformation in the town. Therefore, there is a need to examine the trend and pattern of these changes for proper planning and development of the town. This study examined the dynamics of landuse/landcover change of Damaturu town from 1986 to 2009 using Remote Sensing and Geographic Information System techniques. The following satellite imageries of Damaturu Township were obtained and processed for the analysis: LandSat MSS – 1985 and 1991; Landsat ETM – 1999, and Nig-sat1 ETM of 2009. The images were resampled, rectified and georeferenced to the UTM map projection. A supervised classification approach and maximum likelihood algorithm was used for landuse evaluation and mapping from Landsat data with spatial resolution of 30m. In order to detect landuse/landcover change of Damaturu town from 1986 to 2009, a modified version of supervised scheme was adopted to classify the images into five classes: the built-up, bare surface, cultivated land, wetland and shrubland. The change detection also used the information collected through field survey to complement the results of GIS analysis. Findings revealed that between 1986 and 1991, there were no significant landuse/landcover changes that have taken place in Damaturu town. After the creation of Yobe State in 1991, the policies of planning authorities played vital role in determining the urban landuse pattern which is described as bottleneck along the main roads and consequently the stratification of the lands within the town into high density, medium density, and low density areas within this period (1991-1999). During this period, Damaturu built-up area increased about four times. This significant increase led to corresponding increase in urban area which was responsible for significant decrease of bare surface and shrub land. From 1999 to 2005, the built-up area of Damaturu increased by 7 Km2 while the urban area expanded by about 11 Km2. In addition the large increase of cultivation during that period cannot be unconnected with increased agriculture to meet the demand of the growing population. However, the reduction of bare surface by more than half is the most remarkable of all the landcover changes that have taken place within this period. The growth pattern within this period could be described as radial. Moreover, it was observed that the high density built-up spread out from core-traditional city centre to medium density areas. Within the period of 4 years (2005-2009), the expansion of built-up area of Damaturu was not as significant as the reduction of more than two-third of the wetland, and there was also significant reduction of shrub land. However, the reduction of bare surface during this period is insignificant as development of the town has been steady for quite sometimes. Damaturu areal extent increases geometrically while built-up areas and population increase arithmetically. In addition, findings from field survey revealed serious abuse of the masterplan and development plan of Damaturu town leading to many environmental problems in the town. There is urgent need to review and implement the present Damaturu masterplan to accommodate the present and future changes in the town.