Spatio-Temporal Comparison of Slope-based and Tasseled cap vegetation indices with Land Surface Temperature for Deforestation analysis in Omo and Afi Forest Reserves

Deforestation is a global phenomenon, however, its weight differs across the world. Nigeria is one of the countries that is losing its natural resources to deforestation based on several factors such as agriculture, urbanization, and illegal activities. It is a fact that the healthier a forest is, the more its capacity to clean the environment. Since the advent of remote sensing, its application to studying forests has aided in effective and informative decision-making as they give timely and updated information about several factors contributing to deforestation. This is achieved by manipulating the spectral information of a satellite image. Vegetation indices are one of the analyses carried out on satellite images to determine the physical features of a forested environment based on their reflectivity. Tasseled cap transformation (TCT) is an orthogonal transformation and is different from other conventional indices. It compresses different bands of a satellite image using coefficients to reflect brightness, wetness, and vegetation. Vegetation indices have been used in determining the status of forests and the most used is the Normalized Difference Vegetation Index which is a sloped-based index. However, the orthogonal transformation of satellite bands has not been used to determine the healthiness of a forest. In this study, TCT(Vegetation), Normalized Difference Vegetation Index (NDVI); Modified Soil Adjusted Vegetation Index (MSAVI); Green Normalized Difference Vegetation Index (GNDVI); and Enhanced Vegetation Index (EVI) of Landsat will be assessed to determine the changes in Omo and Afi forest reserves over 30 years. Also, the relationship between the TCT(Vegetation) and the conventional indices (NDVI; GNDVI, MSAVI, and EVI) will be determined, and the best indicator of deforestation in relation to land surface temperature. From Samarawickrama et al., (2017) findings, tasseled cap transformation can be used in place of land cover as it provided more evidence to strengthen the judgment about vegetation health.