Vernal export and retention of biogenic matter in the north-eastern North Atlantic and adjacent Arctic Ocean: The role of the Norwegian Atlantic Current and topography (review)

• Main Author: Paul Wassmann
• Format: Report
• Language: English
• Published: Norwegian College of Fishery Science, University of Tromsoe 2001
• Subjects: Arctic; Arctic Ocean; Barents Sea; Norwegian Sea; Norway; Memoirs of National Institute of Polar Research; north atlantic current; North Atlantic; Northern Norway; Phytoplankton; Polar Research; Zooplankton; Spitsbergen
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=2392; http://id.nii.ac.jp/1291/00002392/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=2392&item_no=1&attribute_id=18&file_no=1

The abundance of suspended chlorophyll a (Chl a) and particulate organic carbon (POC) and its vertical export was investigated on the shelf off northern Norway, off Spitsbergen and in the Barents Sea during biological spring. Accumulation of suspended Chl a>100 mg m^<-2> was only observed in the Barents Sea marginal ice zone and at a distance from the shelf break. Suspended POC concentrations were less variable. Similar results were found for the vertical export of Chl a and POC from the upper layers. It is suggested that the high retention rates of suspended biogenic matter along the shelf break of the Norwegian Sea and the Arctic Ocean north of Spitsbergen, sites influenced by branches of the North Atlantic Current, are caused by top-down regulation of phytoplankton biomass by overwintered and advected zooplankton. Thus a tight coupling appears to exist between primary and secondary production on the shelf areas off northern Norway and Spitsbergen during spring. Classical vernal blooms are not the rule in the area and can only be observed when the distance to the shelf break is significant, advection of zooplankton occasionally is restricted and stratification supports rapid accumulation of phytoplankton.