Microplastic pollution in the surface waters, sediments, and wild crabs of mangrove ecosystems of East Java, Indonesia

Abstract

East Java's mangrove ecosystems are exceptionally susceptible to contamination by anthropogenic activities and degradable marine debris, including plastic. This study aimed to investigate the shapes and distribution of microplastics (MPs) in sediment, water, and wild crabs, as well as the correlation. Wild crabs, sediment, and water originated from ten distinct mangrove ecosystems dispersed throughout northern and southern East Java. The MPs were extracted using digestion and density separation methods. The research identified six discrete shapes of MPs in sediment and water: fiber, fragment, foam, film, pellet, and microbead. The identified MPs were distributed in varying concentrations across various sites. Fibers were prevalent in the majority of water, ranging from 2.5 to 24.90 particles. L⁻¹, with the exception of Gedangan (GD) and Dubibir (DB), whose proportion was relatively low. For the sediments, the seven sites contained a greater proportion of fragments ranging from 1.53 to 1.69 particles. g⁻¹ dw as compared to surface waters. Additionally, each wild crab contained 48 particles identified in the gills and digestive tracts (GIT). Fiber constituted more than 60 % of the total MPs, making it the most prevalent shape in the wild crabs. However, this variety was not preferred. Correlation analysis revealed connections between MPs found in sediment and their presence in crab gills and GIT (p < 0.01). This highlights the potential hazards of biomagnification in East Java's mangrove ecosystems. Factor analysis revealed the influential factors that contribute to pollution in the marine protected areas, emphasizing the intricate nature of coastal contamination. This work enhances comprehension of the distribution and consequences of MPs in mangrove ecosystems, underscoring the necessity for comprehensive efforts to mitigate their effects.