Measuring urban sprawl of small and medium towns using GIS and remote sensing techniques: A case study of Sri Lanka

The measuring of urban sprawl is a challenging task, as it does not have a clear universal method. Therefore, it is worthwhile to investigate whether results differ with the methods utilized, to compute the level of urban sprawl. Accordingly, the study aims to contribute constructively to overcome the two-limitations noted in emerging researches. First, contemporary researches have utilized many methods to measure urban sprawl, but the results of each method has not been compared and contrasted. Secondly, limited studies have been carried out to rank the level of urban sprawl of small and medium towns in either Sri Lanka or elsewhere. Therefore, this study intends to map, quantify, and rank the small and medium towns in Sri Lanka as per the level of urban sprawl by the provided methodological framework. This research utilized the Expansion Intensity Index, Shannon's Entropy value and Landscape Metrics, to evaluate urban sprawl. Ten small and medium towns in Sri Lanka were selected as the case study areas. The study confirms that each method has captured different components of urban sprawl and the towns were ranked accordingly. (c) 2021 National Authority for Remote Sensing and Space Sciences. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/).