Research and Development Center for Efficient Utilization of Coastal Bioresources, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, PR China; Muping Coastal Environment Research Station, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
Research and Development Center for Efficient Utilization of Coastal Bioresources, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, PR China.
J Hazard Mater. 2024 Aug 15;475:134769. doi: 10.1016/j.jhazmat.2024.134769. Epub 2024 May 29.
Microplastics (MPs) are widely distributed in the sea, but the vertical transfer of MPs by marine organisms in coastal area is still poorly understood. In this study, we used laser direct infrared (LDIR) spectroscopy to determine the number and characteristics of MPs deposited by cultured oyster Crassostrea gigas and further compared the differences between MPs of natural deposit and biodeposit in field environments. The amounts of MPs found in the biodeposit of cultured oysters were 3.54 times greater than that in the natural deposition. The polymer types of biodeposit MPs also differed from those of natural deposition. It was estimated that a single oyster can deposit 15.88 MPs per day, which is a figure much higher than the initial results, and hotspots of MPs deposition may be formed within the oyster aquaculture area. We used generalized linear mixed model (GLMM) to further infer the sources of MPs in sediments and found that distance to shore, cultured zone and urban center were important predictors of MPs abundance in sediments of aquaculture area. The above results suggest that cultured bivalves have an important capacity for MPs biodeposition and will further change the vertical distribution pattern of MPs in coastal environments.
微塑料（MPs）广泛分布于海洋中，但海洋生物在沿海地区对 MPs 的垂直迁移仍知之甚少。在本研究中，我们使用激光直接红外（LDIR）光谱法来确定培养的牡蛎 Crassostrea gigas 所沉积的 MPs 的数量和特征，并进一步比较了野外环境中自然沉积物和生物沉积物中 MPs 的差异。培养牡蛎生物沉积物中的 MPs 数量比自然沉积物中的多 3.54 倍。生物沉积物 MPs 的聚合物类型也与自然沉积物中的不同。据估计，一只牡蛎每天可沉积 15.88 个 MPs，这一数字远高于最初的结果，并且在牡蛎养殖区可能形成 MPs 沉积热点。我们使用广义线性混合模型（GLMM）进一步推断沉积物中 MPs 的来源，发现到海岸的距离、养殖区和城市中心是养殖区沉积物中 MPs 丰度的重要预测因子。上述结果表明，养殖双壳类动物具有重要的 MPs 生物沉积能力，这将进一步改变沿海环境中 MPs 的垂直分布模式。
