GIS-based land suitability analysis for potential urban development sites in Diffun, Quirino, Philippines

Abstract

Abstract As the world moves towards urbanization, the demand for land for urban land use increases. If left unmanaged, this might result in the wastage of land that could have been used for more productive purposes, such as agriculture. Other developments can also pose risks to the environment and to those who inhabit it. Therefore, land suitability analyses must be carried out before proceeding to urban planning. This study produced an urban suitability analysis of the municipality of Diffun in Quirino Province as a basis for future urban planning. Conducting this analysis will be very timely, considering that the revision of the municipality’s Comprehensive Land Use Plan (CLUP) will start in 2021. In this study, two methods of doing the analysis were integrated: Boolean overlay and weighted overlay. Using the gathered spatial data, a total of 18 factors and restrictions were produced for the analysis. Restriction layers used in the Boolean overlay method include existing built-up areas, erosion risk, flooding susceptibility, protected agricultural lands, other protected lands, Quirino Protected Landscape (QPL), slope, waterway buffers, and ecotourism site buffers. Meanwhile, the weighted overlay analysis used the following factors: elevation, land-use type, distance to ecotourism sites, distance to local roads, distance to national and provincial roads, proximity to the downtown, distance to protected agricultural lands, distance to waterways, and slope. The weights of the factors were calculated using a pairwise matrix. The study concluded that only 0.32% of the total land area of the municipality is most suitable for urban land-use, while 87.36% is considered not suitable for the development of built-up areas.