Evaluation of NDVI Using SPOT-5 Satellite Data for Northern Ghana

Abstract

Monitoring environment changes has become a necessity as a result of current environment deteriorating due to human activities and climate change. However, in most developing countries like Ghana, acquiring information concerning the current condition and the dynamic changes of the environment for a rapid monitoring is difficult. A method to monitor the environmental condition in Northern Ghana by the way of the vegetation cover using the Normalized Difference Vegetation Index (NDVI) is proposed. The method involves the use of remotely sensed data based on the absorption, transmittance and reflectance of energy by the vegetation which is significantly correlated with the amount of green leaf biomass on ground. The accuracy of this indicator is assessed with other in-situ geographic data. The main aim was to assess whether the NDVI-time series extracted from SPOT-5 images may give reliable information to assess the environment herein vegetation or land cover in Northern Ghana where there is a current rapid environmental change. It is shown that the NDVI data gives some valuable information about the vegetation hence land cover in these areas. The measurement of the amount of greenness in different areas in Northern Ghana would be simple but an objective method to assist in regular evaluation of the environmental situation of an area. The study demonstrated that NDVI technique can be employed to evaluate the vegetation cover and hence monitor the environment. Consequently, this method can be applied for other areas in the country and will be useful as an effective tool for regularly monitoring to support and create environmental awareness about the vegetative changes.