水体中微塑料迁移行为的水力学实验与数值模拟  

Hydraulic experiments and numerical simulation of microplastics migration in aquatic environments

作　　者：李煜瑄 窦明[1,2] 李桂秋[2] 王振[2] 周雨泽 邢澳琪 LI Yu-xuan;DOU Ming;LI Gui-qiu;WANG Zhen;ZHOU Yu-ze;XING Ao-qi(College of Ecology and Environment,Zhengzhou University,Zhengzhou 450001,China;College of Water Conservancy and Transportation,Zhengzhou University,Zhengzhou 450001,China)

机构地区：[1]郑州大学生态与环境学院,河南郑州450001 [2]郑州大学水利与交通学院,河南郑州450001

出　　处：《中国环境科学》2025年第3期1765-1776,共12页China Environmental Science

基　　金：河南省重大科技专项(221100320200);河南省自然科学基金(242300421224);河南省科技攻关计划(222102320211)。

摘　　要：为了解微塑料在水体中的迁移行为,基于水力学实验和受力分析方法识别不同类型微塑料在水体中运动状态变化的水力学参数阈值,进而结合拉格朗日粒子追踪方法建立具有明确物理机制的微塑料迁移模型,对微塑料的迁移运动轨迹进行模拟,预测微塑料的最终运动状态以及归趋,并结合贾鲁河郑州市区段实测数据对模型进行验证.结果表明:贾鲁河郑州市区段中粒径在0.5mm以下的微塑料占比为66.79%,主要的形状是碎片状(31.1%)与纤维状(29.2%).PP作为漂移质迁移,且迁移速率最快;PS与粒径小于0.5mm的PA作为悬移质迁移;PET与粒径大于0.5mm的PA作为推移质进行推移运动或静止在水底.在流量为14m^(3)/s与20m^(3)/s的两种工况下,微塑料在36h内的滞留率为43.79%与47.85%,其中颗粒占比最大,PA与PET为主要的滞留微塑料种类.The migration behavior of microplastics in aquatic environments is governed by complex interactions among hydraulic,physical,and material-specific factors.This study integrates hydraulic experiments and force analysis to identify the critical hydraulic parameter thresholds influencing state transitions of different microplastic types in freshwater systems.A Lagrangian particle tracking method is then employed to develop a migration model grounded in well-defined physical principles.This model simulates microplastic trajectories,predicting their ultimate movement states and environmental fate.The model is validated using field data from the urban section of the Jialu River in Zhengzhou,China.Results indicate that 66.79%of microplastics in this section have particle sizes smaller than 0.5mm,with fragmented(31.1%)and fibrous(29.2%)shapes being predominant.Polypropylene(PP)migrates as floating debris with the highest velocity,while polystyrene(PS)and polyamide(PA)particles smaller than 0.5mm migrate as suspended load.In contrast,polyethylene terephthalate(PET)and PA particles larger than 0.5mm migrate as bedload or remain stationary on the riverbed.Under flow rates of 14m^(3)/s and 20m^(3)/s,retention rates of microplastics over 36hours were 43.79%and 47.85%,respectively,with PA and PET constituting the major retained microplastic types.These findings provide valuable insights into the hydrodynamic behavior and environmental fate of microplastics,offering guidance for pollution management in freshwater systems.

关 键 词：微塑料 水力学实验 迁移模型 粒子追踪法 贾鲁河 

分 类 号：X703.5[环境科学与工程—环境工程]