Synergy between microplastic and sediments within the aquatic system

微塑料是人为污染的来源之一，由于其在地球表面的高浓度，正成为一个环境问题。虽然大型塑料由于其可见性，可以很容易地使用传统方法收集，但由于微型和纳米塑料规模小，能够与河岸土壤颗粒和其他类型的塑料凝聚，因此完全了解从陆地到河流、河口和海洋的路径和命运是未知的。然而，控制它们在水生系统中的传输和沉积到河床上的物理机制尚不清楚。由于粘聚力的作用，微塑料与河床沉积物之间的相互作用可能导致它们聚集形成更大更重的颗粒，因此更容易沉积在河床上。需要很好地理解这些过程，以便为制定能够解决和减少微塑料对环境的影响的数值模型和未来的环境政策提供信息。本项目旨在对微塑料与水生系统中沉积物颗粒之间的双向相互作用提供新的理解。这位博士研究员将在卡迪夫大学独特的水槽设施中进行实验，使用一系列水流和泥沙测量技术，如粒子图像测速仪、声学多普勒测速仪、超声波测距距离传感器和高速相机。该项目与“工程学”和“与环境变化共存”的研究主题很好地结合在一起，这是因为这项研究的范围是“环境”和“水”。

Microplastics are a source of anthropogenic contamination that are becoming an environmental concern due to their high concentrations across the earth's surface. Whilst large plastics can be collected easily using traditional methods due to their visibility, a full understanding of the pathways and fate of micro- and nano-plastics from the land to the rivers, estuaries and the sea is unknown, due to their small scale and ability to agglomerate with riparian soil particles and other plastic types. Nevertheless, the physical mechanisms which govern their transport in aquatic systems, and deposition onto the riverbed is yet to be elucidated. The interaction between microplastics and bed sediments due to cohesive forces can lead to their aggregation forming much larger and heavier particles that are therefore easier to deposit on the river bed. These processes need to be well-understood to inform the development of numerical models and future environment policies that can address and reduce the impact of microplastics on the environment.This project aims at providing a new understanding to the two-way interaction between microplastics and sediment particles within the aquatic system. The PhD researcher will conduct experiments in unique hydraulic flume facilities at Cardiff University using a range of flow and sediment measurement techniques, such as particle image velocimetry, acoustic doppler velocimetry, ultrasonic ranging distance sensors and high speed cameras. The project aligns well with both the 'Engineering' and 'Living with environmental change (LWEC)' research themes, due to the remit of this studentship lying within "Environment" and "Water".