RS and GIS for City’s environmental intelligence and precision planning

Abstract:

This study attempted the characterization of land uses in Ile-Ife city, Nigeria in order to provide environmental intelligence information needed for precision planning. The study identified key land cover and uses in Ile-Ife, produced a land use characterization map and offered recommendations for more precise planning based on environmental intelligence information gathered from the characterization process. The methodological approach used involved field survey and observation aimed at familiarizing with the study area and taking down satellite coordinates of highly conspicuous features on the satellite imagery; land use categorization exercise using Anderson’s categorization scheme; remote sensing classification of land cover and data extraction using ILWIS 3.2; and creation of land use data layers and data extraction using the GIS capabilities of ArcGIS 3.2a. In the course of this study, five key land cover types (built-up areas or settlements, vegetation, bare rocks, water bodies and wetlands) and three key land use types (residential, commercial and institutional land uses) were identified. Results from the remote sensing classifications revealed that vegetation (mostly secondary in nature) still covers a majority of about 61.2% (407.1 km² out of 668.8 km²) of the city’s total land area; this is followed by built-up areas which covers about 32.2% (215.5 km²), and then bare rocks (5.3%-35.3 km²), wetlands (1.2 %-8.0 km²), and water bodies (0.2%-0.9 km²) respectively. The GIS analysis shows that residential land use covers about 80.1% of the built-up areas (172.6 km²- 25.8% of the total land area), institutional land use covers about 17.4 % of the built-up area (37.6 km²-5.6% of the total land area), while commercial land use covers about 2.5 percent of the built-up areas (5.3 km²-0.8% of the total land area). The statistical data extracted and visual observations made from this study provided environmental intelligence information needed for precision planning. Strategies for ensuring the overall sustainability of the natural environment, and the sanity of city life in Ile-Ife were offered based on the findings of this study. This study also offered recommendations on ways of further improving the planning structure of Ile-Ife using remote sensing and GIS technologies.