We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Vertical transport of buoyant microplastic particles in the ocean: The role of turbulence and biofouling
AI summary Read the abstract
Researchers modeled how turbulence and biofouling interact to determine the vertical movement of buoyant microplastic particles in the ocean. They identified three distinct flow regimes that govern whether microplastics stay at the surface, oscillate, or sink to the seafloor. The study helps explain the observation that even low-density microplastics are found in deep ocean sediments, suggesting biofouling-driven density changes are a key transport mechanism.
This study investigates the interactions between turbulence and biofouling and their influence on the vertical transport of buoyant microplastic particles in a marine environment. We explore the sinking characteristics for a range of particle densities and sizes, focusing on comparing laminar and turbulent flows with diffusivity profiles typical of the North Pacific Ocean. The results show the existence of three flow regimes based on the relative importance between turbulent fluctuations and biofilm growth. The biofouling process determines the vertical motion of microplastic particles of sizes in the millimeter range. In contrast, particles in the micrometer range are found to follow flow trajectories without any significant influence from biofouling. We observe that turbulence, on average, promotes the beginning of the vertical particle settling; for example, a high-density polyethylene particle of 1 mm in size has an average settling onset of 10 days in the presence of turbulence, while in its absence, this occurs in 19 days. We also show that turbulence causes buoyant microplastic particles smaller than 0.1 mm to spend their entire lifespan underwater. Finally, the probability distributions for particle size after 100 days in the ocean reveal that particle density strongly influences the biofilm thickness for particles larger than 10μm. We will discuss the implications of these results for tracking the motion of microplastic particles in large-scale regional or global numerical models.
More Papers Like This
Ups and Downs in the Ocean: Effects of Biofouling on Vertical Transport of Microplastics
AI summary Read the abstract
Researchers developed the first theoretical model to simulate how biofouling, the growth of microbial biofilms on plastic surfaces, affects the vertical movement of microplastics in the ocean. The model predicts that depending on particle size and density, fouled microplastics may float, sink to the seafloor, or oscillate at intermediate depths. These findings help explain why small microplastics seem to disappear from the ocean surface and suggest they may concentrate at mid-water depths where vulnerable species live.
Modelling submerged biofouled microplastics and their vertical trajectories
AI summary Read the abstract
Using an ocean circulation model, researchers simulated the vertical trajectories of biofouled microplastic particles of different sizes across three ocean regions with distinct biological and physical properties. Larger particles (0.1 to 1.0 mm) showed rapid oscillatory sinking and resurfacing behavior with cycles under 10 days, while smaller particles oscillated over up to 130 days, explaining how biofouling drives microplastic distribution through the water column.
The Fluid Mechanics of Ocean Microplastics
AI summary Read the abstract
This review examined the fluid mechanics governing microplastic transport in marine environments, covering buoyancy, Stokes drift, turbulence, and biofouling effects across scales from surface films to deep-sea accumulation zones. The authors identified key knowledge gaps in predicting vertical transport and small-scale aggregation processes.
Modeling the trajectories of floating and non-floating microplastic particles in the water column
AI summary Read the abstract
Researchers modeled the trajectories of both floating and non-floating microplastic particles in freshwater and marine water columns, accounting for turbulence-induced mixing, buoyancy differences, and flow characteristics that determine vertical and horizontal distribution. The study highlights that while low-density polymers like polyethylene and polypropylene are expected to concentrate at the surface, turbulent mixing drives significant depth distribution across aquatic environments.
Modeling submerged biofouled microplastics and their vertical trajectories
AI summary Read the abstract
Researchers modeled how biofouling — the growth of algae and microbes on plastic surfaces — affects the vertical movement of microplastic particles in the open ocean. Biofouling increased sinking rates, causing microplastics to accumulate at depth rather than floating at the surface. This has implications for understanding where microplastics end up in the water column and how they are ingested by deep-water organisms.
Research digests by email
When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.