Impact Quantification of Decentralization in Urban Growth by Extracting Impervious Surfaces Using ISEI in Model Maker

Abstract

Decentralization problems in Africa have caused some infrastructure disparity between country capitals and distant districts. In Ghana, less public investment has created a gap between implementation results and theoretical benefits. Spectral indices are a good approach to extracting impervious surfaces, which is a good method of measuring urbanization. These are restricted by complexity, sensor limitation, threshold values, and high computational time. In this study, we measure the urbanization dynamics of Wa District in Ghana by applying a proposed method of impervious surface extraction index (ISEI), to evaluate the decentralization policy using Landsat images from 1984–2018 and a single S2A data. Comparing our proposed method with five other existing indexes, ISEI provided good discriminated results between target feature and background, with pixel values ranging between 0 and +1. Other indexes produced negative values. ISEI accuracy varied from 84.62–94.00% while existing indexes varied from 73.85–90.00%. Our results also showed increased impervious surface areas of 83.26 km2, which is about 7.72% of total area while the average annual urban growth was recorded as 4.42%. These figures proved that the quantification of decentralization is very positive. The study provides a foundation for urban environment research in the context of decentralization policy.

Urban sprawl and its impact on sustainable urban development: a combination of remote sensing and social media data

“…This information is useful for activity pattern analysis as shown by (Dangermond and Goodchild 2020;Kainz 2020;Monsivais et al 2017). Other studies in urban areas have utilized social media data and satellite imagery to gain insights on situational awareness of human activities Stefanidis et al 2011), urban land use mapping (Hu et al 2016); service-oriented architecture applications (Pashova and Bandrova 2017) spatiotemporal analysis in the urban environment impacted by human activities (Monsivais et al 2017;Sumari et al 2019b); and, determination of users' locations, tweets, and home area from Twitter data to understand the patterns of social media usage (Hu et al 2019;Lee et al 2014;Sdoukopoulos et al 2018;Tsou et al 2015;Weiler, Grossniklaus, and Scholl 2016; Zhou and Zhang 2016).…”

“…Ecosystem services are the benefits that ecosystems provide for both human societies and the earth itself with reference to regulation, provision, and cultural significance. These include provisioning services such as food, water, timber, and fiber; regulating services that affect climate, floods, disease, wastes, and water quality; cultural services that provide recreational, esthetic, and spiritual benefits; and supporting services such as soil formation, photosynthesis, and nutrient cycling (Huq et al 2019;Sedami et al 2015;Terfa et al 2020;Twumasi et al 2019;Zhang, Weng, and Shao 2017;Zhang et al 2019b). Human beings depend on these ecosystem services because they are vital for human well-being.…”