Characterization and Quantification of Urban Expansion and Impact on Urban Planning Practice in Morogoro Municipality, Tanzania

Abstract

Globally, there are extensive concerns about urban expansion. In response, urban expansion detection and assessing land use and land cover (LULC) changes have become significant methods to support decisions about suitable land resource use. The major concern with urban expansion aside from habitat destruction, is the distribution of human resources and basic needs especially to the community living in the newly settlement patches. This study applied a series of Landsat images to quantify the rate and characterise the pattern of urban expansion and assess  its impact on  urban planning practice over a 30 years period from (1990 to 2020). Change detection was supported by images and supervised classification method. Random Forest (RF) classification method was used to achieve imagery classification, and from classification results were validated by Kappa index of Agreement (KIA) and overall accuracy (OA) methods. To analyze these changes, we used Urban Expansion Intensity Index (UEII) landscape metrics to characterize the changes in the spatial patterns across Morogoro landscape and it’s impact of urban expansion on other types of land cover. The findings indicated that from 1990 to 2010 built up areas have been experiencing an increase of 3.9% to 18.1% respectively,   while non-built up areas have decreased from 96.1% to 81.9% respectively within 30 years period time .Urban planning practice in 1990 to 2020 increased of planned land where by plan before development on land increase from 0.8% to 6.6% while the plan after development increase from 0.2% to 10.8% of the total urban area in the same year. In significant changes in urban expansion and urban planning practice experienced were highly correlated in 2010 to 2020. Based on the outcomes of this study, it is recommended that municipal authorities should consider initiatives in urban planning to reverse the existing trend of urban development in order to recover the sustainability and resilience of the urban situation. The conclusions clarified the spatial pattern of urban change and its influencing factors in Morogoro municipality over the past 30 years and could provide helpful reference for the future urban planning.