Analyzing And Modeling The Spatio-Temporal Urban Growth: A Case Of Wolaita Sodo Town, Southern Ethiopia

Abstract

Urbanization is a global trend with significant environmental effects, calling a clear policy at all levels. To develop the appropriate policies and monitoring systems for urban expansion, it is crucial to understand the urbanization-induced spatio-temporal dynamics of land use and land cover and future potential urban growth. However, little is known in the context of Ethiopian urban centers. The aim of this study, Wolaita Sodo Town, one of the rapidly growing urban centers in Southern Ethiopia, is considered to analyze its spatiotemporal growth from 1990 to 2022 and to predict its potential future expansion in the years 2030, 2040, and 2050. Through supervised image classification using the support vector machine algorithm, LULC maps of the study area in 1990, 2003, 2016, and 2022 were prepared, and the spatiotemporal changes of LULC were investigated. The dynamics of landscape structure in the study area were then investigated using FRAGSTATS and various landscape metrics at the class and landscape levels. The Multi-Layer Perceptron neural network and the Markov chain method on the land change modeler were used to forecast the growth extent of the study area for the years 2030, 2040, and 2050 using drivers representing proximity, biophysical, and socioeconomic variables. The relationship between population growth and urban built-up area expansion was explored using regression analysis. The results show that the built-up area has undergone about 27% expansion annually in the past 32 years, indicating rapid urban growth. The urban landscape of the town was more fragmented in 1990-2003, as compared to that of 2003-2016 and 2016-2022. Landscape of Sodo town was highly heterogeneous in the year 2003. Moreover, the built-up area, which presently occupies 11.37% of the study area, would increase to 13.76%, 17.03%, and 20.06% in the years 2030, 2040, and 2050, respectively. The temporal expansion of built-up area was linearly related to the growth of population. This study would support planners and stakeholders to plan a new direction before negative outcomes become irreversible. The formulation of urban planning policies should also aim to create a balance between the sustainable use of limited resources and socio-economic needs.