Identifikasi Lahan Terbangun Sepanjang Garis Pantai di Teluk Manado Berbasis Citra Satelit Menggunakan NDBI

Abstract

The transformation of built-up land in coastal areas is a phenomenon driven by social, economic, and environmental dynamics, especially in rapidly urbanizing regions like Manado Bay. Coastal areas serve as strategic hubs for economic, tourism, and residential activities, yet they are also vulnerable to development pressures that threaten environmental sustainability. This study aims to analyze changes in built-up land along the coastline of Manado Bay between 2017 and 2023 using Sentinel-2 satellite imagery. A spatial analysis approach is applied using the Normalized Difference Built-up Index (NDBI) to identify built-up land. Spatial and temporal data analysis helps identify land change patterns and their influencing factors. The findings indicate a significant increase in built-up land within a 100m to 500m radius from the shoreline, mainly due to commercial facilities such as hotels and restaurants, as well as tourism-supporting infrastructure. Meanwhile, residential expansion is evident in areas 1000m to 3000m from the coast, driven by urbanization and population growth. Key factors influencing land changes include economic development, urbanization, infrastructure expansion, and weak spatial planning policies. Uncontrolled development, particularly outside designated zoning areas, has led to environmental degradation, such as natural vegetation loss and increased coastal disaster risks. This study highlights the usefulness of Sentinel-2 imagery in accurately mapping land use changes, supporting sustainable coastal development planning. These findings provide a basis for decision-making in the integrated and environmentally conscious management of coastal regions.