GIS-Based Spatio-Temporal Analysis of Vegetation Dynamics, Urban Expansion, and Land Surface Temperature in Davao City
Abstract
The Earth's surface and atmosphere have been substantially modified by the growth of anthropogenic activities and urbanization. Changes in the composition and operation of the urban ecological system will affect the health of city dwellers by increasing the risk of heat exposure, increasing the risk of violence, illness, and mortality, and reducing labor productivity. Davao City is currently undergoing rapid urbanization, and no comprehensive study has examined the effects of the changes on vegetation indices, urban expansion, traffic density, and land surface temperature, which are likely to affect the area. This study analyzes the spatio-temporal change in vegetation indices, built-up expansion, traffic density, and land surface temperature from 2018 to 2022 using Landsat 8 imagery and GIS tools, particularly QGIS. The results show a moderate negative relationship between NDBI and NDVI (r = −0.4313), a strong positive relationship between NDBI and LST (r = 0.6216), and a weak negative relationship between NDVI and LST (r =−0.2495). Results highlight the interconnected influence of urbanization, vegetation dynamics, and thermal conditions within the study area, underscoring the need to integrate green infrastructure, particularly along major road networks, to mitigate rising land surface temperatures.