Remote Sensing-GIS Supported Land Cover Analysis of Gashaka-Gumti National Park, Nigeria

Abstract

This paper, using remotely acquired data and field survey analyzed land cover types, classified (supervised) and observed mean tree species distribution between the two sectors of the Gashaka-Gumti National Park (GGNP). Landsat Enhanced Thematic Mapped (ETM), 1999 imagery; Two scenes P186R054 and P186R055 were analyzed using Integrated Land and Water Information System (ILWIS) soft ware version3.2a for the land cover types and classification. Using GPS, sample units coordinates and altitude were determined and species distribution per 625m2 of unit area were surveyed in the field while, soil types and characteristics were restricted to published documents and field checks. Percentages of cover types and mean species distribution per unit area as well as significance variation in mean species distributions between the two sectors were calculated using student t- test. Result of the data analysis revealed based on set criteria seven land cover classes, which further computed into their percent (%) surface cover. Result of the of the cover types indicated Wood/grass lands constituted 52.42%, gallery forest 20.84% lowland forest 8.46%, montane grass land 9.05% montane forest 5.25%, water bodies/streams 0.62%, rock outcrop 1.80% and bare surfaces 1.54%. The observed mean distribution of tree species per sample unit show means of 41, 48, 46 densities and 9, 10, 9 diversities for the northern, southern sectors and the entire park respectively. Soil type, altitude, nearness to water channels and slope gradient are noted among the determinant factors in observed cover types and distribution pattern.

Key Words: Biodiversity, Gashaka-Gumti, Land cover, Remote Sensing-GIS, Species distribution