Spatio-Temporal Analysis of Built-Up Land Expansion in Central Kotamobagu Using NDBI and Google Earth Engine

Abstrak

This study examines the spatial and temporal dynamics of built-up land expansion in Central Kotamobagu using Google Earth Engine and the Normalized Difference Built-up Index (NDBI). The study aims to identify changes in land cover, particularly the transformation of vegetated areas into built-up surfaces, and to examine the spatial distribution and temporal development of urban expansion. NDBI was applied to satellite imagery processed through the Google Earth Engine platform to extract built-up land information and quantify changes over the study period. The results indicate a continuous increase in built-up areas, reflecting the ongoing process of urban growth in Central Kotamobagu. The expansion is closely associated with population growth, increasing economic activities, and the development of urban infrastructure. Spatially, built-up land expansion is initially concentrated in the urban core and areas with relatively high accessibility, particularly along established transportation networks. Over time, these developed areas have progressively extended toward surrounding locations, indicating a pattern of outward urban expansion. This spatial development suggests that accessibility and existing urban structures play important roles in shaping the direction and intensity of land transformation. The findings highlight the importance of systematic monitoring of built-up land dynamics to support environmentally sustainable urban and regional planning. The integration of NDBI and Google Earth Engine provides an efficient and reproducible approach for identifying, mapping, and monitoring urban land development, offering valuable spatial information for managing future urban growth and minimizing potential environmental impacts in Central Kotamobagu.