A spatial temporal approach to assess the impact of urbanization on peri-urban cultural heritage sites : a case study of Naggalabi Coronation SIte (2002-2015)

Abstract

Uganda possesses a number of peri-urban landscapes blessed with cultural heritage of which one peri urban heritage site is thoroughly studied for urbanization impacts in this master’s dissertation. Naggalabi site among others, is highly prone to urbanization impacts directly or indirectly due to its location being very prime to Kampala City. The dissertation therefore assessed the impact of urbanization on this site using a spatial-temporal approach involving Object Based Image Analysis (OBIA) and Classification. It was aimed at quantifying, visualizing, and predicting the impacts of urbanization on this site to avail data for research on urbanization trends on cultural sites in Uganda which rather remains scanty, with impacts and effects not known, quantified or predicted in a scientific way. The research adopted both a qualitative and quantitate approach in design. OBIA and Classification of three VHR images between 2002 and 2015 were used to analyze the existing state and subsequent changes arising from urbanization of Naggalabi Cultural site in a spatial temporal approach. The images, IKONOS of 2002, WorldView2 of 2010 and a Pleiades-1 of 2015 underwent atmospheric corrections, geo-referencing/projections, pan sharpening, image pixel resizing, clipping extents, buffering, segmentations and rule-based threshold classification. Three Land Cover (LC) maps were derived for the respective years which were further modeled using Markov Chain Model for future predictions. Purposive sampling done on five informants with interview guides examined the names, nature and locations of cultural spots. A very good classification accuracy of over 85% based on overall accuracy and Kappa coefficients was obtained for the three LC Maps obtained for each epoch. These maps portrayed four LC classes that is, Vegetation, Bare land, Built-up and Background, which were analyzed visually and statistically for years 2002, 2010 and 2015. Results showed 13 cultural spots identified with varying names, roles, nature, visual appearance and physical state between 2002 and 2015. Explicit land cover conversions to built-up areas were identified. A lower annual land conversion rate from other land cover classes to built-up areas shown as 9.7% (2001 to 2010) while an increased annual rate of 12.6% (2010 to 2015). From 2002 to 2015, urbanization directly impacted on the site through amplified overall land cover conversion (about 54.255 hectares) from mainly vegetation and bareland to built-up giving an overall percentage gain of built-up to 189.5% with annual rate of 14.6%. Future trends analysis predicted continued urbanization at the peripherals, major roads and nearby towns of Kivu and Kimbejja by 2035. Policies on planning, training, conservation and protection of tangible cultural sites are recommended.