Ahmed Abu Sayeed Shafiuddin, Billah Md Masum, Ali Mir Mohammad, Guo Laodong, Akhtar Shahrina, Bhuiyan Md Khurshid Alam, Islam Md Saiful
Department of Fisheries and Marine Science, Noakhali Science and Technology University, Noakhali, Bangladesh.
Inter-Departmental Research Centre for Environmental Science-CIRSA, University of Bologna, Ravenna Campus, Via S. Alberto 163, 48123, Ravenna, Italy.
Environ Sci Pollut Res Int. 2025 Feb;32(9):5435-5456. doi: 10.1007/s11356-025-36044-9. Epub 2025 Feb 10.
Water and sediment samples were collected from 20 sampling sites within two major river systems within the world's largest mangrove ecosystem. The primary objectives of the study were to determine MPs' abundance, composition, and potential ecological risks and to identify the factors influencing their distribution and characteristics. Results revealed MP abundances, ranging from 2 to 53 items/m in water and 17 to 177 items/kg in sediment. The most prevalent types of MPs were films, fragments, foams, and fibers, with the most abundant fragments. Transparent MPs of various colors, such as red, green, blue, white, and yellow, were commonly observed. Additionally, sizes of MPs ranged from < 0.5 to 5 mm, with particles < 0.5 mm dominating in water and 4-5 mm particles prevailing in sediment. Six major polymers were identified, including polystyrene (PS), polyamide (PA), Polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), and ethylene propylene diene monomer (EPDM), with PS being the most abundant in both river systems. Linear mixed effect models showed that factors, such as distance from Mongla port and water velocity impacted MP abundance in water, while distance from Mongla port, total organic carbon (TOC), and total phosphorus (TP) contents affected their distribution in sediment. The Shannon-Weaver Index revealed a higher MP diversity in the Shela River compared to the Pasur. Overall, the pollution load index (PLI) and polymeric hazard index (PHI) indicated that MPs impacted both river systems, but the finding from the ecological risk index (ERI) was negligible at the individual sites. Our study recommends the long-term monitoring of MP abundance and implementation of strict regulations to reduce MPs in aquatic environments and proposes various engineering and biotechnological approaches for effective MP remediation. Further research is needed to identify both point and non-point sources of MPs and develop comprehensive strategies and policies to mitigate plastic pollution in the mangrove ecosystem.
在世界上最大的红树林生态系统的两个主要河流系统内的20个采样点采集了水和沉积物样本。该研究的主要目的是确定微塑料的丰度、组成和潜在生态风险，并确定影响其分布和特征的因素。结果显示，水中微塑料的丰度为每立方米2至53个，沉积物中为每千克17至177个。最常见的微塑料类型是薄膜、碎片、泡沫和纤维，其中碎片最为丰富。常见各种颜色的透明微塑料，如红色、绿色、蓝色、白色和黄色。此外，微塑料的尺寸范围为小于0.5至5毫米，小于0.5毫米的颗粒在水中占主导地位，4至5毫米的颗粒在沉积物中占主导地位。鉴定出六种主要聚合物，包括聚苯乙烯（PS）、聚酰胺（PA）、聚对苯二甲酸乙二酯（PET）、聚乙烯（PE）、聚丙烯（PP）和乙丙橡胶（EPDM），其中PS在两个河流系统中含量最高。线性混合效应模型表明，距离蒙格拉港的距离和水流速度等因素影响水中微塑料的丰度，而距离蒙格拉港的距离、总有机碳（TOC）和总磷（TP）含量影响其在沉积物中的分布。香农 - 韦弗指数显示，与帕苏尔河相比，谢拉河的微塑料多样性更高。总体而言，污染负荷指数（PLI）和聚合物危害指数（PHI）表明微塑料对两个河流系统都有影响，但生态风险指数（ERI）在各个站点的结果可忽略不计。我们的研究建议对微塑料丰度进行长期监测，并实施严格的法规以减少水生环境中的微塑料，并提出各种工程和生物技术方法以有效修复微塑料。需要进一步研究以确定微塑料的点源和非点源，并制定全面的战略和政策以减轻红树林生态系统中的塑料污染。
