Spatio-temporal analysis of built-up expansion (BUA): the case of metropolitan Davao's third congressional disctrict

Abstract

The migration of individuals from rural regions to urban areas leads to a growing need for housing, infrastructure, and services, which drives social, economic, and environmental changes. This study uses Landsat Data to generate LULC maps across multiple timeframes. Utilizing satellite images acquired from the United States Geological Survey (USGS), the research employs various techniques, including image processing, classification and accuracy testing to analyze dynamic shifts in five land classes. The study’s methodology involves using a Quantum Geographic Information System (QGIS) for LULC classification, vector layer intersection for refining results, and change detection through pivot tables and zonal statistics. The findings provide insights into spatial patterns and temporal trends within the district. The data indicates that forest areas consistently occupy most of the land, although gradual decline is observed, particularly between 2020 and 2023. Agricultural and barren lands show fluctuating trends, with agricultural land experiencing a notable decrease in specific years due to urbanization pressures. Built-up areas (BUA) have seen continuous growth, reflecting the district’s shifts towards urban development, which can be linked to its proximity to the Central Business District (CBD), which leads to land conversion. The data underscores the need for sustainable land management practicing balance amidst pressures from rapid urban growth.