Monitoring of Urban Growth Patterns in Rapidly Growing Bahir Dar City of Northwest Ethiopia with 30 year Landsat Imagery Record

Abstract

Monitoring urban growth patterns is an important measure to improve our understanding of land use/land cover (LULC) changes and a central part in the proper development of any city. In this study, we analyzed the changes over a period of 30 years (1985–2015) in Bahir Dar, one of the rapidly growing cities of northwest Ethiopia. Satellite images of Landsat TM (1985, 1995, and 2008), and OLI (2015) were used. The classification was carried out using the object-based image analysis technique and a change analysis was undertaken using post-classification comparison in GIS as a novel framework. An accuracy assessment was conducted for each reference year. Eight LULC types were successfully captured with overall accuracies ranging from 88.3% to 92.9% and a Kappa statistic of 0.85 to 0.92. The classification result revealed that cropland (66%), water (12.5%), and grassland (6%) were the dominant LULC types with a small share of areas covered by built-up areas (2.4%) in 1985. In 2015, cropland and water continued to be dominant followed by built-up areas. The change result shows that a rapid reduction in natural forest cover followed by grassland and wetland occurred between the first (1985–1995), second (1995–2008), and third (2008–2015) study periods. On the contrary, build-ups increased in all three periods by 9.3%, 121.3%, and 44.8%, respectively. Although the conversion between the LULC classes varied substantially, analysis of the 30-year change matrix revealed that about 31% was subject to intensive change between the classes. Specifically, the built-up area has increased by 250.5% during the study years. The framed approach used in this research is a good repeatable example of how to assess and monitor urban growth at the local level, by combining remote sensing and GIS technologies. Further study is suggested to investigate detailed drivers, consequences of changes, and future options.

Land-use change dynamics and urban growth simulations in a medium-sized city of Mangaluru, India through CA-based SLEUTH urban growth model

“…Fig. 6 shows that the most important driving forces of urban growth in Mangaluru are coe cients of slope resistance (50), spread (34) and road gravity (27).…”

“…The world is getting urbanised in an unprecedented manner, which according to the United Nations estimations, currently 55% of the world's population is urbanised and is anticipated to rise to 68% by 2050 (United Nations, 2018). Urban growth is a major force driving the land use and land cover changes across the world (Bhat, Sha q, Mir, & Ahmed, 2017; Radwan, Blackburn, Whyatt, and Atkinson, 2019; Kindu, et al, 2020). The process of urbanisation has been the most drastic contributor to environmental change, destroying biodiversity, hydrological system, loss of agricultural land, etc.…”

Evaluating the Quality of Land Information for Peri-Urban Land-Related Decision-Making: An Empirical Analysis from Bahir Dar, Ethiopia

“…The reasons to choose this study area are (1) high rate of urbanization and prevalence of peri-urban areas; (2) continuous development of new informal settlement patterns and frequent disputes over land; (3) representative area for many other regional cities in Ethiopia; (4) easy access to data both from the government (at different levels) and households and (5) one of the pilots and exemplary area in developing modern land information [41]. Bahir Dar is expanding horizontally with an unpredicted rate of urban expansion [28,42,43]. This increasingly leads to the existence of land use disputes, informality, and land governance challenges [44,45].…”

Perspective Chapter: Spatio-Temporal Analysis of Urban Expansion

“…Unless properly managed, it can result in serious negative environmental and socioeconomic consequences, such as urban heat islands, reductions in green spaces, insufficient infrastructure and services, and inefficient utilization of resources [1][2][3]. Analyzing the spatio-temporal dynamics of the built-up area of a particular urban landscape is the primary step in understanding the impacts of urbanization [4]. Knowledge about the spatial pattern and intensity of urban land changes is critical for a variety of issues, ranging from human-environmental interactions and the provision of urban environmental services to land-use policy development for landscape and urban planning toward sustainable urbanization [5].…”