Marine litter and microplastic pollution in mangroves pose significant threats. This study of litter in Omani mangroves revealed an average density of 0.83 to 21.92 items/m2. Quriyat lagoon emerged as the most contaminated area, hosting 133 items/m2, while Qurum Natural Reserve lagoon showed the least contamination at 10 items/m2. Plastics constituted 73–96 % of the litter, with microplastic levels in sediment ranging from 6 to 256 pieces/kg. Al-Sawadi’s lagoon had the highest microplastic abundance (27.52 ± 5.32 pieces/kg), in contrast to Al Qurum’s Marine Protected Area with the lowest (0.60 ± 1.12 pieces/kg). Microplastics, categorized as fragments, pellets, and fibers, were distributed across zones 40.05 % landward, 30.97 % seaward, and 28.98 % in the middle mangrove zones. Primary plastic polymers identified were Polyethylene (PE) at 40 % and High-Density Polyethylene (HDPE) at 28 %, along with others found in specific areas. Our findings provide essential baseline data for future monitoring efforts and management strategies in Oman and other countries. full text
