Persistence of biogeochemical alterations of deep-sea sediments by bottom trawling

Bottom trawling grounds have been expanding to deeper areas of the oceans since the mid-XXth century, and mitigating strategies aimed to protect fish stocks, such as temporal trawling closures, have recently been implemented. Here we investigated the biogeochemical properties of sediment from a deep...

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Bibliographic Details
Authors: Paradis, Sarah|||0000-0002-7035-0538, Goñi, Miguel|||0000-0001-7682-8064, Masqué Barri, Pere|||0000-0002-1789-320X, Durán, Ruth|||0000-0002-7423-1069, Arjona-Camas, Marta|||0000-0002-0862-856X, Palanques, Albert|||0000-0003-2544-2342, Puig i Alenyà, Pere|||0000-0001-6189-5504
Format: article
Publication Date:2021
Country:España
Institution:Universitat Autònoma de Barcelona
Repository:Dipòsit Digital de Documents de la UAB
Language:English
OAI Identifier:oai:ddd.uab.cat:237714
Online Access:https://ddd.uab.cat/record/237714
https://dx.doi.org/urn:doi:10.1029/2020GL091279
Access Level:Open access
Keyword:Biogeochemistry
Bottom trawling
Erosion
Organic matter
Sediment
Description
Summary:Bottom trawling grounds have been expanding to deeper areas of the oceans since the mid-XXth century, and mitigating strategies aimed to protect fish stocks, such as temporal trawling closures, have recently been implemented. Here we investigated the biogeochemical properties of sediment from a deep-sea trawling ground in Palamós Canyon (NW Mediterranean) to assess the effects of a 2-months trawling closure in the recovery of sedimentary organic matter. In comparison to untrawled areas, the continuous erosion and sediment mixing in trawling grounds led to coarser reworked sediments impoverished in organic carbon (∼30% loss) and promoted the degradation of labile compounds (52-70% loss). These impacts persisted after the temporal trawling closure, highlighting that this management strategy is insufficient to restore the seafloor. Considering the continuous expansion of bottom trawling grounds, this activity could have significant and irreversible biogeochemical impacts on ocean margins at a global scale, hampering their carbon burial capacity.