Microplastic Dynamics in Sediment Layers of Two Ramsar‐Designated Wetlands

Abstract

ABSTRACT Little is known about the vertical and spatial dynamics of microplastics in relation to hydrology and land use, particularly in African context. This study aimed to assess the abundance, type, colour and vertical distribution of microplastics in sediment from two Ramsar‐designated wetlands, the Makuleke and Nylsvley. Sediment core samples were collected from five depth intervals (Depth: 0–20, 20–40, 40–60, 60–80 and 80–100 cm) for microplastic quantification. Microplastics were detected across all depths, with slight variations. Fibres and beads had high abundance in relation to other types. Makuleke exhibited significantly high concentrations of fragments and films than Nylsvley, driven largely by hydrological connectivity and anthropogenic inputs. These findings suggest that wetland protection status alone does not shield against microplastic contamination, which can persist in deep substrate layers for extended periods. Furthermore, the findings highlight the importance of integrated wetland management, enhanced plastic waste policies and ongoing research on the fate of microplastics in freshwater sediment systems.