MODELLING URBAN SPRAWL OF THE GREATER PORT HARCOURT CITY USING REMOTE SENSING AND GEOGRAPHIC INFORMATION SYSTEM TECHNIQUES

Abstract

In recent decades, urban sprawl has been viewed as one of the most pressing issues that cities over all the world in developing countries are batting with. It is often associated mostly with rural-urban migration and rising birth rates, where development is given precedence over urban planning. The study focuses on the urban sprawl of the greater Port Harcourt city. The greater Port Harcourt city is expanding at an unprecedented rate, with no adequate planning or statistical record. The study intends to address this issue by building models using remote sensing and geographic information system (GIS) tools in order to analyze urban sprawl in the Greater Port Harcourt city. To achieve this set of objectives, three sets of Landsat sensors, which were captured at different time intervals (1986, 2006, and 2021), were used to monitor urban sprawl in the study area. The Geographic Positioning System (GPS) was used during the field visit to collect the ground control points of some locations within the city. The National Population Commission (NPC) data was also employed to acquire the demographic statistics. The result of the study shows that the built-up area had expanded from 47.35 km2 (10.76%) in 1986 to 71.05 km2 (16.14%) in 2000 and to 284.68 km2 (64.68%) in 2021. This expansion in built-up area generates a decline in wetland, bare land, and forest land from 112.296 km2 (25.51%), 61.369 km2 (13.94%), and 160.152 km2 (36.39%) in 1986 to 72.468 km2 (16.47%), 86.486 km2 (19.65%), and 136.853 km2 (31.09%) in 2000, and to 42.810 km2 (9.73%), 10.858 km2 (13.94%), and 40.8384 km2 (9.28%) in 2021. The findings of the study are important because they give the government information on how quickly the study area is expanding, allowing it to adopt an appropriate planning strategy. In conclusion, the study demonstrate that remote sensing and GIS techniques can be utilized to successfully monitor the environment on a regular basis in order to investigate urban sprawl and inform better decision-making.