APPLICATION OF GIS AND MULTI-CRITERIA DECISION ANALYSIS FOR LANDFILL SITE SELECTION IN ABEOKUTA NORTH LGA OF OGUN STATE
DUROJAIYE EMMANUEL; NOFIU A. OLUWABUKUNMI AND ADEWARA M. BABALOLA, Volume 6 Issue 1, 2022 Pages 83-93, Published: 2023-06-23
Abstract
This study is based on site selection for Solid Waste dumpsite in Abeokuta North LGA, Nigeria using Geographic Information Systems (GIS) and Multi-criteria Decision Analysis (MCA) techniques. Five criteria were used for the study. This criteria were classified in to two: the constraint criteria (buffers). While the factor criteria involves road types, soil, elevation, slope and land use. The study was divided in to three phases. In the first phase the constraint criteria were standardize using Boolean logic, a score of 0 was assigned to the restricted area, while 1 to unrestricted area. Then all the five criteria were overlaid to generate a restriction map. For the second phase, factor criteria were standardize using fuzzy membership, with a range of numbers from 0 –1. The factor criteria were then weighted using Analytical Hierarchical Process (AHP) and then overlaid, to get a suitability map. The final phase combine the result of the first and second phase to get most suitable sites for landfill. The result revealed Six different sites; the Highly Unsuitable site occupy 64.64Km2 (8%), Very Unsuitable site occupy 290.88 km2 (36%), Unsuitable site covered 56.56 km2 (7%), Suitable site covered only 161.6km2 (20%), Very Suitable site covered 24.24km2 (3%) and then Highly Suitable site covered 21.08% (26km2). Some communities within the Very Unsuitable sites are Atapa Ikoyi, Ogoye, Ijale Orile, Ijale Papa; those within unsuitable sites are, Aiyetoro, Imala, Olohunda; those within suitable sites are Idi Emi, Abeokuta south; those within very suitable sites are Idiya, Adimo,Igbo Aje; those within Highly Suitable sites are Gbopa ehin, Igbasa, Owode