Measuring Desertification in continuum: Normalized Difference Vegetation Index-based Study in the Upper East Region, Ghana

摘要

This paper builds on current research in desertification and approaches design to assist in the accurate measurement of desertification in both spatial (pixel level) and temporal scales taking cue from two earlier studies by Lampray in 1975 and Prince in 1998. These studies vary both in time and space, hinge on different perceptions which directed the methodological approach and conclusions, their points of divergence and convergence have proven to be the strength of many current desertification studies including this one. The focus of this study was to find an indicator-based based approach, i.e. Using Normalized Difference Vegetation Index (NDVI) which can measure desertification in a continuum over long term. Whereas long–term and continuous analysis is important, this study finds that spatial pattern of land degradation in the UER differ from place to place and from time to time which may be attributed to land use types and intensity. The study therefore concludes that although the general surfaces appearance is important, localized land degradation and short term degradations are likely to be overlooked. Assessing desertification in continuum should reflect both temporal and spatial land degradation degradation trajectories. These trajectories have implications for identifying the cause or causes of degradation and developing targeted approach both at the regional and local levels. In the case of the UER, efforts at combating desertification would more likely be effective at locality level where decisions on land preparation, including the use of fire, the timing and the method of cultivation is likely to be effectively enforced. Key Words : desertification, continuum, pixel, spatio-temporal