We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Marine litter in submarine canyons: A systematic review and critical synthesis
AI summary Read the abstract
This systematic review finds that less than 1% of the world's submarine canyons have been studied for marine litter, revealing a major knowledge gap. Plastics that accumulate in deep-sea canyons break down into microplastics over time, potentially affecting marine food chains that humans depend on for nutrition.
The presence of marine litter is of concern in submarine canyons, although research in this area is still in its infancy. A critical synthesis and literature review selecting studies with primary data of benthic marine litter at depths of over 50 m revealed important gaps in the knowledge, with information on the impact of macroplastics in deep-sea environments still scarce. Less than 1% of medium to large submarine canyons mapped have been studied in any measure for marine litter, with over 91% of the canyon studies located in European waters. Imaging techniques are now the main tools used for sampling, overtaking trawling methods despite the continued growth of the latter for marine litter deep-sea research. Enumeration of litter was diverse with over 75% using abundance for quantification. Despite the existence of litter protocols available for deep-sea environments, over 73% of studies did not use any. There was no standardization in the implementation of established classification protocols, which were either not used in full or were customized in part. Fishing-related categories do not feature as a top-level category in the classification hierarchy in any of the protocols, yet over 50% of publications featured fishing materials as a main category, pointing to a more intuitive activity-based categorization of litter instead of a materials-led approach from the established protocols. Furthermore, interactions between litter and the surrounding environment and biota are very much underreported with little or no consensus between how the data are analyzed and expressed. There were no discernible patterns between litter density, composition and broad geographical location of canyons, with individual topographical characteristics, hydrodynamic regimes and anthropogenic activities being determining factors in how submarine canyons are affected by litter. Overall, there is no apparent framework to allow comparison of studies and due to the different methods of identifying, enumerating, quantifying and classifying marine litter, or lack of data on position and morphological setting within the canyon system. The evidence provided within this study highlights a ‘call to action’ for an urgent need to standardize and unify methodologies with new or established protocols to fully understand the impact of marine litter in submarine canyons.
More Papers Like This
Submarine canyons as microplastic reservoirs: Insight from a reduced complexity model
AI summary Read the abstract
Scientists modeled how underwater canyons act like giant funnels, trapping tiny plastic bits (microplastics) as they wash off coastlines instead of letting them spread across the deep ocean floor. Their findings suggest over 89% of this plastic pollution may get stuck in these canyons, turning them into hidden hotspots of contamination that could harm the sea creatures living there. Since these ecosystems are connected to the broader marine food web that eventually reaches our plates, understanding where microplastics accumulate helps researchers track potential long-term exposure risks for both ocean life and people.
Submarine canyons as microplastic reservoirs: insight from a reduced complexity model
AI summary Read the abstract
Scientists found that underwater canyons along coastlines act like giant sponges, trapping up to 85% of tiny plastic particles that flow into them from polluted surface waters. This means these deep-sea environments are becoming major storage sites for microplastic pollution, which could seriously harm the sea creatures living there. Since many of these affected sea creatures end up in our food chain, this plastic buildup in ocean canyons could eventually impact human health through the seafood we eat.
The combined role of near-bed currents and sub-seafloor processes in the transport and pervasive burial of microplastics in submarine canyons
AI summary Read the abstract
Researchers studied how near-bed currents and sub-seafloor processes interact in submarine canyons to transport microplastics to deep-sea sediments, finding that canyon systems record temporal trends in plastic pollution but that physical disturbance can obscure or rework the depositional signal.
Marine litter-fauna interactions: a standardised reporting framework and critical review of the current state of research with a focus on submarine canyons
AI summary Read the abstract
This review and framework paper found that marine litter interacts with ocean wildlife in under-studied ways — particularly in submarine canyons, which trap more litter than other seafloor environments. The authors identified six categories of harm (entanglement, ingestion, smothering, habitat provision, adaptive behavior, and encounter) and created a standardised reporting framework to make future studies globally comparable. Better tracking of how plastic debris physically harms marine animals is a prerequisite for understanding the full ecological cost of ocean plastic pollution.
Plastics in the deep sea – a global estimate of the ocean floor reservoir
AI summary Read the abstract
This systematic review estimates the total amount of plastic pollution resting on the deep ocean floor worldwide. The research reveals that the deep sea serves as a massive reservoir for plastic waste, which is concerning because as these plastics break down into microplastics over time, they can be consumed by deep-sea organisms and re-enter the food chain.
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.