Urban Land Use Land Cover Change Detection: A Case Study Of Adama City, Ethiopia.

Abstract

This study uses Land Use and Land Cover Change (LULCC) computed from Landsat TM, ETM, ETM+ and OLI datasets of 1990, 2000, 2010 and 2020 respectively. The study aimed to simulate future LULCC using landsat images in the fastest-growing Adama city. Supervised classification and maximum likelihood algorithm was applied to estimate the LULC for years 1990, 2000, 2010, and 2020. These were analyzed by using ArcGIS10.8, Erdas imagine 2015 and IDRISI V.17 to make clear land use structure. The change detection of multiple Landsat images was conducted between 1990 and 2020. A hybrid simulation model that combined the Markov-Chain and Cellular Automata (MC-CA) was used to simulate the future LULC for 2030, 2040 and 2050.The historical LULC change data of 1990–2000, 2000–2010, 2010-2020 and 1990–2020 were used as a baseline. Both transition rules and transition area matrix for the period 1990– 2000, 2000–2010, 2010-2020 and 1990–2020 were produced quantitatively using the Markov chain model. After that, the biophysical and socio-economic factors were standardized using fuzzy and determined using the analytic hierarchy process (AHP) and aggregated using weighted linear combination (WLC) under multi-criteria evaluation (MCE) approach was used to produce the transition suitability image. The model was validated using simulated and observed LULC 2020 by using kappa parameters; with the overall kappa index 0.84%; which indicates good kappa index values. The result shows that the proportion of built up area was 2.5% in 1990, this figure rose to just over 17% in 2020, with annual growth rates of 6.4%, 6.2%, and 14.7% in the three study phases, indicates an expansion in built-up area was 4493 ha, resulting in agriculture, barren land, vegetation, and water bodies losing 463 ha, 3760 ha, 223 ha, and 46 ha, respectively from 1990 to 2020.The simulated result indicated that built up area covers 26%, 28% and 30% of the total area coverage according to prediction at 2030, 2040 and 2050 respectively, indicate that these patterns of bare land changing into built-up and vegetation will continue over the next 30 years due to urban expansion and reforestation. It is predicted that the conversions of other land-use types into built-up areas will persist in the southern and northern areas of the city, as east-west growth trend of the city is hampered by the natural barriers of hilly ridges of Kechema in west & Didibisa and Migira in east, despite the city has almost a compact settlement shape. The output of the study provides useful information for land use planners and decision makers to make better decisions in improving future land use policies and formulating management strategies within the framework of sustainable land use planning