An Assessment of Changes in Land-Use and Land-Cover within the Kiri Lake, Nigeria (1976-2014)

This paper assesses the land-use and land-cover changes within the Kiri lake basin between 1976 and 2014 - a period of 38 years, using remotely sensed data and geographic information systems (GIS). Since 1982 when the Gongola River was impounded and Kiri Lake created, various anthropogenic activities such as agriculture, irrigation, deforestation, fishing, and construction have taken place. The cumulating of these human activities together with natural factors has led to environmental degradation and the damage of the ecosystem of the lake basin. Landsat MSS image of 1976, Landsat TM of 1986 and Landsat ETM+ images of 1991 and 2014 were acquired, classified and analysed between 1976 and 2014. Area calculations of the arc GIS 10.2.2 software were used to derive the trends, rates and magnitudes of changes, while map overlay was employed for assessing the nature and location where the changes have taken place. The study reveals that the rate of deforestation and erosion in the study area is linked to the methods of farming practices as well as the removal of the catchment vegetation as part of land preparation. Uncontrolled human settlement and demand for fuel wood etc., was another issue to contend with. If this issue of land degradation is not appropriately dealt with in the future, it could lead to the decrease in the power generating capacity of the proposed hydropower component due to filling up with silt materials and the ultimate shortening of the life span of the dam. Finally, it is hoped that the findings from the study will provide useful insight into the current state of the environment, and the recommendations proposed in this paper would equally be helpful to mitigate, control and to improve the management of the basin.