Land cover changes, built-up and vegetation density, and the Urban Heat Island (UHI) phenomenon in Pekanbaru City

Abstract

Pekanbaru city has a high population growth rate and is currently experiencing increasing urbanization, which triggers urban expansion. Urban development causes changes in land cover patterns and a decrease in environmental quality. The development of residential areas and infrastructure causes a reduction in vegetation, which has an impact on Land Surface Temperature (LST) and allows the emergence of the Urban Heat Island (UHI) phenomenon. This study aims to analyze the changes of land cover, the correlation of LST to Normalized Difference Built-up Index (NDBI) and Normalized Difference Vegetation Index (NDVI), and then investigate the UHI phenomenon in Pekanbaru City. The method of research is quantitative, the data sources are Pekanbaru City, an administrative map, and Landsat 8 OLI/TIRS imagery, and then spatially analyzed by ARGIS and QGIS. The novelty is utilized guided classification and maximum likelihood algorithms for land cover classification, which revealed significant changes over the five-year period between 2018 and 2023 in Pekanbaru City. For 5 years, there was a change in land cover in the city of Pekanbaru, where the area of water bodies increased by 23%, palm increased by 5%, built-up area increased by 34%, and vegetation increased by 10%, while the area of bare land decreased by 57%. There are significant changes in built-up and vegetation density. The correlation between land surface temperature and built-up density is a positive relationship; however, it is negatively correlated with vegetation density. There is an urban heat island phenomenon in Pekanbaru City, characterized by a more significant surface temperature than the UHI’s threshold.