Urban Development Pressure: Challenges in Ensuing Green Cover in Unawatuna – Rumassala Area, Sri Lanka

J.N.D. Jayathunga, P. G. Dikwaththa


The continuous development of cities has created significant issues in the planning and management of an area’s environment and landscapes. This is due to the requirement for supported products such as housing, business facilities, infrastructure networks, and environmental protection. Decades of uncontrolled development have had a significant impact on both the natural environment and the quality of human life. The goal of this study is to examine the change in green cover owing to development over the last few years and to
estimate the development pressure index to ensure green cover in the Unawatuna-Rumassala area. Defining the development pressure to prioritise green cover in order to protect the Unawatuna-Rumassala region as an ecotourism destination. Based on the model builder methodology in ArcGIS, this study presents an improved way of analysing development pressure. The development pressure index focuses on finding areas that are prone to significant development pressure. The development pressure was identified using the following
criteria: accessibility, population density, building density, and land use and land cover. In 2009 and 2016,  Landsat satellite images were utilised to analyse the Normalized Difference Vegetation Index (NDVI), which aids in identifying changes in green cover over time. The simulation findings demonstrate that NDVI levels have changed dramatically between 2009 and 2016. On elevated and low topographic slopes where human activity was prevalent, moderate NDVI values shifted to low NDVI values. Furthermore, development pressure has concentrated in the Rumassala protection zone, having a significant impact on the area’s ecosystem. The
increased development pressure in the studied area has also resulted in biodiversity deterioration.

Keywords: Development Pressure Index, Normalized difference vegetation index (NDVI), Green cover, Urbanization, Urban Planning