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TitreArctic Ocean seafloor geomorphic features and benthic habitats - relevance for conservation and marine spatial planning
TéléchargerTéléchargement (publication entière)
AuteurHarris, P T; Macmillan-Lawler, M
SourceProgram and abstracts: 2017 GeoHab Conference, Dartmouth, Nova Scotia, Canada; par Todd, B J; Brown, C J; Lacharité, M; Gazzola, V; McCormack, E; Commission géologique du Canada, Dossier public 8295, 2017 p. 55, https://doi.org/10.4095/305855 (Accès ouvert)
LiensGeoHab 2017
Année2017
ÉditeurRessources naturelles Canada
Réunion2017 GeoHab: Marine Geological and Biological Habitat Mapping; Dartmouth, NS; CA; mai 1-4, 2017
Documentdossier public
Lang.anglais
DOIhttps://doi.org/10.4095/305855
Mediaen ligne; numérique
Référence reliéeCette publication est contenue dans Todd, B J; Brown, C J; Lacharité, M; Gazzola, V; McCormack, E; (2017). Program and abstracts: 2017 GeoHab Conference, Dartmouth, Nova Scotia, Canada, Commission géologique du Canada, Dossier public 8295
Formatspdf
ProvinceRégion extracotière du nord
SNRC16; 19; 26; 27; 28; 29; 36; 37; 38; 39; 46; 47; 48; 49; 56; 57; 58; 59; 66; 67; 68; 69; 76; 77; 78; 79; 86; 87; 88; 89; 97; 98; 99; 107; 117; 120; 340; 560
Lat/Long OENS-180.0000 180.0000 90.0000 64.0000
Sujetstechniques de cartographie; océanographie; milieux marins; études côtières; conservation; organismes marins; écologie marine; gestion des ressources; peuplements biologiques; etudes de l'environnement; écosystèmes; benthos; marges continentales; plate-forme continentale; talus continental; topographie du fond océanique; plateaux sous-marins; dorsales médio-océaniques; sédiments marins; dépôts glaciomarins; topographie glaciaire; planification; biogéographie; glaciation; climat; Pléistocène; biologie; changement climatique; géologie marine; géologie des dépôts meubles/géomorphologie; géologie de l'environnement; Nature et environnement; Phanérozoïque; Cénozoïque; Quaternaire
Illustrationssketch maps
ProgrammeGéoscience de la gestion des océans, Géoscience en mer
Diffusé2017 09 26
Résumé(disponible en anglais seulement)
The Arctic Ocean is geomorphically unique among ocean basins for its large percentage areas of continental shelf (51.8%), plateau (9.2%), spreading ridges (4.8%), shelf valleys (14.0%), submarine canyons (16.1%), and terraces (24.6%), all of which are greater in area proportionately compared with the earth's other ocean basins. It also is distinguished by its proportionately small areas of abyssal plains, escarpments and seamounts as well as the absence of any hadal zones or deep ocean trenches (Fig. 1). These observations are relevant to the distribution of benthic species and Arctic biogeography, because seafloor geomorphic features are surrogates for benthic habitats, at the relevant (broad) spatial scale.
Two categories of geomorphic feature can, in particular, be attributed to Pleistocene glaciation and the attendant export of sediment to the ocean basin: glacial troughs and submarine canyons. Glacial troughs characterize 24% of the Arctic shelf, second only to Antarctica where 40% of shelf area is glacial trough. Arctic submarine canyons are twice the size of those in non-polar regions. Canyons in the Arctic have an average size of 890 square kilometres compared to the overall (global) average size of 463 square kilometres. Canyons comprise an average of 11.2% of the continental slope area, attaining maxima of 16.1% of the continental slope of the Arctic Ocean. The larger size and greater fractional slope-area of Arctic canyons is attributed to glacial export of sediments into the Arctic Ocean during Pleistocene ice ages.
Conservation measures in the Arctic include the declaration of marine protected areas (MPAs) that are located mainly along the coasts and continental shelf areas of Arctic countries. This MPA configuration results in a lack of protection for categories of deep sea features such as submarine canyons, seamounts and spreading ridges, and the unique benthic ecosystems that inhabit them. As anthropogenic climate change causes a gradual decline in sea ice cover, previously inaccessible benthic habitats may become vulnerable, for the first time, to human exploitation (i.e. fisheries and oil and gas industries).
GEOSCAN ID305855