We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Elucidating the vertical transport of microplastics in the water column: A review of sampling methodologies and distributions
AI summary Read the abstract
This review synthesized sampling methodologies and findings on microplastic vertical distribution in the water column, identifying that surface trawl studies dramatically underestimate total water column burdens and that sinking behavior, biofouling, and hydrodynamic processes create complex depth-dependent distribution patterns.
There have been numerous studies that have investigated floating microplastics (MPs) in surface water, yet little data are currently available regarding the vertical distribution in the water column. This lack constrains our ability to comprehensively assess the ecological effects of MPs and develop further policy controls. In this study, we reviewed current progress of sampling methodologies, the distribution patterns, and the physiochemical properties of MPs throughout the water column. Three sampling protocols were identified in this study: bulk, net and submersible pump/in-situ sampling. In different regions, the vertical patterns of MPs in the water column varied with depth, which is possibly related to the morphological characteristics, polymeric densities, and biofouling of the MPs. The results of this review revealed that fibrous and fragmented MPs comprised over 90% of the total MPs by quantity, of which fibrous MPs constituted the majority (43%-100%). In addition, polyethylene terephthalate, polyamide, polyethylene, polyvinyl chloride, and polypropylene have been widely identified in previous studies. To minimize the impact caused by various sampling protocols, the use of a volume gradient trail experiment and a unified mesh size of 60-100 μm for the initial concentration are recommended according to the results of this review. Given the limited knowledge regarding the vertical transport of MPs in the water column, harmonized sampling methods should first be developed. The mechanisms of this process can be separately considered for different water bodies, such as freshwater systems, coastal waters, and pelagic zones. The presence of these anthropogenic pollutants in the water column poses a threat to the largest but most vulnerable habitats of life on earth, and hence they merit further investigation.
More Papers Like This
Difference in the fate of surface and subsurface microplastics: an example for open and coastal waters
AI summary Read the abstract
Researchers compared the behavior of surface and subsurface microplastics in open ocean and coastal waters, finding that vertical mixing and biological processes move substantial quantities of plastic below the surface. Subsurface sampling revealed microplastics that would be missed by surface net tows alone. The findings suggest that surface-based microplastic monitoring significantly underestimates the total plastic burden in the ocean water column.
Microplastics in the marine environment: A review of their sources, distribution processes, uptake and exchange in ecosystems
AI summary Read the abstract
Researchers reviewed the literature on how microplastics move through marine environments, finding that while plastic density helps predict vertical distribution in the water column, biological interactions — such as ingestion and biofouling — better explain why buoyant plastics end up at great ocean depths and transfer through food webs. The review underscores that microplastic bioaccumulation is driven as much by ecology as by physical properties.
Concentration Depth Profiles of Microplastic Particles in River Flow and Implications for Surface Sampling
AI summary Read the abstract
This study measured microplastic concentration depth profiles in river flow and found that particles are not uniformly distributed in the water column, with implications for sampling strategy and the accuracy of estimates of total microplastic transport.
The vertical distribution and biological transport of marine microplastics across the epipelagic and mesopelagic water column
AI summary Read the abstract
Remotely operated vehicles and custom samplers were used to collect microplastics from depths of 5–1000 m in Monterey Bay, finding that microplastic concentrations in mesopelagic waters (200–600 m depth) were comparable to or higher than surface concentrations. The study demonstrates that the deep ocean is not merely a sink but an active reservoir of microplastics vertically transported by biological organisms.
The vertical distribution of buoyant plastics at sea: an observational study in the North Atlantic Gyre
AI summary Read the abstract
Field measurements of buoyant plastic particles at multiple depths in the ocean showed that concentrations decrease sharply below a few meters, with turbulence mixing plastics downward. The data validate model predictions and confirm that surface net trawls substantially undercount total plastic in the water column.
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.