Threats Of Microplastic Pollution On Sea Turtle Nesting Habitat In Mangkai Island, Anambas Islands, Indonesia

This study investigated the abundance, morphological characteristics, color composition, and vertical distribution of microplastics in sediments collected from four sea turtle nesting beaches (Empung, Teluk Kado, Sekanji, and Suit) on Mangkai Island, Anambas Islands, Indonesia. Three independent sediment cores were collected from each beach and sectioned into four depth intervals (0, 20, 40, and 60 cm), yielding a total of 12 sediment cores and 48 sediment samples. Microplastics were extracted using hydrogen peroxide digestion, zinc chloride density separation, filtration, and microscopic identification. Differences in total microplastic abundance among nesting beaches were evaluated using one-way analysis of variance (ANOVA), whereas morphological composition, color composition, and vertical distribution were assessed descriptively. Microplastic abundance ranged from 1.11 ± 0.22 to 2.09 ± 0.33 particles g−1, with no significant differences among the four nesting beaches (F(3,8) = 0.802, p = .527). Fibers were the dominant morphological type, followed by fragments and films, while black, transparent, and brown particles represented the predominant color categories. Microplastics occurred throughout the 0–60 cm sediment profile, including depths corresponding to the natural nesting zone of sea turtles. These findings provide baseline information on microplastic contamination in protected sea turtle nesting habitats and support future studies integrating sediment characteristics and ecological responses to strengthen evidence-based conservation strategies.