Utilisation of Multicriteria Decision Making with Remotely Sensed Data in a GIS Environment for Optimal Location of Waste Disposal Sites Around the Sokoto Metropolis, Sokoto State, Nigeria

摘要

Rapid population growth, technological development and urbanisation have brought about increase in the amount of waste being generated worldwide. Waste, domestic or industrial have caused serious pollution of the environment and have become a major problem globally. Population growth goes hand in hand with spatial growth because increase in population size results in increase in the use of urban space. Since, human induced environmental problems require detailed study. Environmental problems caused by waste therefore can be alleviated by proper locating of waste disposal sites through careful study and understanding of lithospheric and hydrospheric conditions around the geographical area we live on the earth surface. Remote sensing is an excellent source of data for mapping lithospheric and hydrospheric and other earth surface parameters. Similarly, Geographic Information System (GIS) is a tool that is being widely used now a days in suitability analysis because it has the ability to store, retrieve, recognize, correlate and analyse spatial relationships between these parameters. On the other hand, Multi Criteria Decision Making (MCDM) is a decision support tool highly used in GIS for suitability or optimum location analysis to arrive at the best decision by weighing importance. Currently, Sokoto metropolis which serves as the capital of Sokoto State and located in the North-Western part of Nigeria, over the years has been growing in terms of population size and related spatial growth. This has hitherto resulted in an increase in waste generation. This study therefore, utilises Multicriteria Decision Making (MCDM) with remotely sensed data in a GIS environment for optimal location of waste disposal sites around the Sokoto Metropolis. Quickbird image tiles/scenes covering the study area were acquired from the Nigerian Air Space Research and Development Agency (NASRDA) and imported into the Idris Andes Software in TIFF format where the smaller images covering the study area were mosaicked and combined with a windowed DEM image and analysed in a GIS environment using MCDM. Results has shown that the study is cost effective and indicated alternative waste disposal sites to the existing three sites around the Sokoto metropolis with more prospective alternative areas which are free from health risks and less environmentally endangering.