Deep-sea scavenging amphipod assemblages from the submarine canyons of the Western Iberian Peninsula

[摘要] Submarine canyons have often been identified as hotspots ofsecondary production with the potential to house distinct faunalassemblages and idiosyncratic ecosystems. Within these deep-seahabitats, assemblages of scavenging fauna play a vital role inreintroducing organic matter from large food falls into the widerdeep-sea food chain.

Free-fall baited traps were set at different depths within threesubmarine canyons on the Iberian Margin. Amphipods from the trapswere identified to species level and counted. Scavenging amphipodassemblages were compared at different depths within each canyon and betweenindividual canyon systems. Using data from literature, abyssal plainassemblages were compared to submarine canyon assemblages. Samples fromcanyons were found to containcommon abyssal plain species but in greater than expectedabundances. It is proposed that this isa result of the high organic carbon input into canyon systems owingto their interception of sediment from the continental shelf andinput from associated estuarine systems. Community composition differedsignificantly between the submarine canyons and abyssal plains. The cause ofthis difference cannot be attributed to one environmental variable due to thenumerous inherent differences between canyons and abyssal plains.

[学科分类] 地球化学与岩石