MAPPING TREE CROWN AREA AND ABOVEGROUND BIOMASS IN THE AGROFORESTRY LANDSCAPE OF WEST AFRICA
M. Usman J.E. Nichola M. S. Wong
AbstractIn semi-arid Sudano-Sahelian ecological zone of West Africa, tree cover is one of the important element of the local livelihood, maintained by farmers in their farmed parklands through agro-forestry practices. Spatial estimation of tree canopy cover and above ground biomass in agroforestry landscapes is of great interest for both regional resource management and environmental assessment. This study used high resolution WorldView-2 (WV-2) imagery for mapping tree crown cover and aboveground biomass in the agroforestry landscape of northern Nigeria as a case study. Geographic Object Based Image Analysis (GEOBIA) was used to delineate tree crown, tree crowns extracted from WV-2 data shows a good linear relationship with reference tree crown data with R2 = 0.78. Field inventory data was used for tree level above ground biomass estimation using already developed species specific allometric equations in the West Africa. A linear model for the estimation of AGB (ton.ha-1) was developed using tree crown area (m2) extracted from WV-2 data with R2 = 0.70.