Composition and Spatial Distribution of Marine Debris in the Waters of Inner Ambon Bay

Marine debris pollution has become a global threat to coastal ecosystems, especially in tropical regions with high human activity. This study investigates the composition and spatial distribution of marine debris in Inner Ambon Bay waters using a multi-location approach. Sampling was carried out at six stations representing different activity types: ports (Halong), dense river estuaries (Galala), mangrove ecosystems (Waiheru), residential areas (Passo), and areas with mixed characteristics (Poka). Waste composition was analysed based on material classification, including plastic, glass/ceramic, rubber, plastic foam, metal, fabric, paper/cardboard, wood, and other materials. Results showed a dominance of plastic waste, with 1,166 items (61.47%) out of 1,896 total items. The spatial distribution revealed significant heterogeneity, with Poka station recording the highest plastic density (357 items) and Hunuth the lowest (47%). Variability in waste composition reflects specific human influences: port areas mainly contained glass and ceramics (41.3%), densely populated settlements predominantly exhibited domestic plastic waste (67.1%-92.1%), and commercial areas showed a diverse range of materials with a significant rubber presence (15%). Non-biodegradable materials accounted for 94-95% across sites, indicating persistent long-term contamination. The Waiheru mangrove ecosystem experienced the highest pollution levels, with plastics accounting for 92.1%, primarily accumulating through river transport. The clear connection between human activities and pollution patterns emphasises the need for site-specific management strategies. This study provides essential baseline data for creating marine debris management plans focused on human activity profiles in tropical coastal areas and improves understanding of marine debris distribution within sustainable coastal management frameworks.