Remote Sensing And Gis Based Site Suitability Analysis For Future Urban Development: A Case Of Ambo Town And Surrounding Area

Abstract

One of the critical issues in urban planning is the determination of appropriate locations for future urban growth in and around the town. This study demonstrates the use of Remote sensing and Geographic Information System (GIS) based Multi-Criteria Decision Analysis (MCDA) techniques for selection of suitable sites for urban development of Ambo Town. Nine factors (proximity to lineament, proximity to road, proximity to river, proximity to school and health center, land use land cover, slope, soil, geology and proximity to existing built-up area) were identified for criteria evaluation. The thematic maps of these criteria were prepared and standardized using pair wise comparison matrix known as Analytical Hierarchy Process (AHP). A weight for each criterion was given by comparing them with each other according to their importance, the consistence of comparing matrix were checked by calculating the consistence ratio (CR). The consistency ratio of this study indicated that 0.045 which is less than 0.1. Thus, consistent matrix was formed which was acceptable in order to combine all the layers. Finally using these weights all maps layer were integrated and overlaid to generate final site suitability map for the urban development. The final site suitability map was reclassified to five suitability classes (highly suitable, moderately suitable, less suitable, very less suitable and unsuitable). The findings of this study revealed that from the total area of 83.91Km2 found in study area, 16.13% (13.35km2) of total area was occupied by existing built-up and not considered for this study. From the rest of 70.38 km2 total area, 36.13% (30.32Km2) area is highly suitable, 31.59% (26.51Km2) area is moderately suitable, .80% (8.22Km2) area is less suitable, 2.63% (2.20Km2) area is very less suitable and 3.74% (3.14Km2) area is unsuitable for future urban development. This result shows that most of the area selected as highly suitable for future urban development are open area, shrubs, bushes and agricultural land, areas having flat slope, area far away from river and areas far away from lineaments. This study allows the local people as well as planners for the appropriate plans of land use planning in sustainable urban development of Ambo town.