Are deep-sea organisms dwelling within a submarine canyon more at risk from anthropogenic contamination than those from the adjacent open slope? A case study of Blanes canyon (NW Mediterranean)

Ecological Role of Submarine Canyons and Need for Canyon Conservation: A Review

“…The hydrodynamics of canyons favor the quick movement of labile material to the lower slope, where local benthic environments might become sinks of pollutants (Puig et al, 1999;Looser et al, 2000;Palanques et al, 2008;Castro-Jiménez et al, 2013;Cossa et al, 2014;Sanchez-Vidal et al, 2015). In the NW Mediterranean, general accumulation patterns indicate that organisms collected inside Blanes Canyon had higher concentrations of POPs than individuals collected on the adjacent open slope (Koenig et al, 2013). These inputs could be the consequence of enhanced vertical transport of hydrophobic particles associated with chemical pollutants, the dispersal of which is driven by local hydrodynamic processes that regulate flux and sediment re-suspension patterns (Koenig et al, 2013).…”

“…In the NW Mediterranean, general accumulation patterns indicate that organisms collected inside Blanes Canyon had higher concentrations of POPs than individuals collected on the adjacent open slope (Koenig et al, 2013). These inputs could be the consequence of enhanced vertical transport of hydrophobic particles associated with chemical pollutants, the dispersal of which is driven by local hydrodynamic processes that regulate flux and sediment re-suspension patterns (Koenig et al, 2013).…”

“…Nevertheless, submarine canyons are increasingly subjected to different stressors, not only in relation to fishing (Company et al, 2008;Martín et al, 2008;Orejas et al, 2009;Puig et al, 2012), but also to oil and gas extraction (Harris et al, 2007). Moreover, the hydrodynamic processes of canyons enhance the transport of litter (Mordecai et al, 2011;RamirezLlodra et al, 2013;Tubau et al, 2015) and chemical pollutants from the shelf to deep-sea environments Koenig et al, 2013;Pham et al, 2014). Canyons have also been used as dumping areas for tailings of land-based mining (Hughes et al, 2015;Ramirez-Llodra et al, 2015).…”

Marine litter on the floor of deep submarine canyons of the Northwestern Mediterranean Sea: The role of hydrodynamic processes

“…Plastic, which has been found in large amounts in this study (72% of litter objects), may persist for centuries in the marine environment (South Carolina Sea Grant Consortium, 2008); but plastics also degrade into fibres and particles (microplastics) that can be ingested by suspension and epibenthic feeders (Thompson et al, 2004). Vessel derived paint pots and chips, which are rather common at some Mediterranean locations (Galil, 2006), have also been referred to as potential long-term sources of chemical contamination, including persistent organic pollutants that accumulate in deep Mediterranean species (Koenig et al, 2013). Von Moss et al (2012) reported that microplastics can either be eliminated through defecation or retained in the tissues of the exposed animals, however, virtually nothing is known about the consequences of long-term litter degradation, which products may eventually pervade across trophic levels (Kukulka et al, 2012;Cozar et al, 2014).…”

Natural variability of hepatic biomarkers in Mediterranean deep-sea organisms

“…During these events, cold shelf water masses cascade down the continental slope transporting large amounts of sediment and organic matter, resulting in an increased particleassociated contaminant input to the deep-sea environment (Salvadó et al, 2012). In addition, previous work has shown that deep-sea organisms dwelling within submarine canyons in the NW Mediterranean are particularly at risk of experiencing adverse contaminant-induced effects (Koenig et al, 2012a). These findings further stress the need for the implementation of regular environmental monitoring studies in these areas.…”