Distribution of dinoflagellate cysts in the Canadian Arctic marine region

Abstract

The Canadian Arctic is a major gateway for transport of freshwater from the Arctic Ocean to the North Atlantic. This region comprises the Beaufort Sea, the Canadian Arctic Archipelago (CAA) and northern sections of Baffin and Hudson bays. Subregional differences include major freshwater runoff to the Beaufort Sea and Hudson Bay, presence of Pacific and Atlantic Intermediate water in the west, and Atlantic Water in Baffin and Hudson bays. Principal component analysis of 50 core-top samples shows four subregional dinoflagellate cyst assemblages. Outer Beaufort Shelf Assemblage I is co-dominated by Operculodinium centrocarpum s.l. and Brigantedinium spp., with minor cysts of Pentapharsodinium dalei, Algidasphaeridium? minutum s.l. and cysts of Polykrikos spp. Assemblage II in the Canadian Arctic Archipelago is co-dominated by Brigantedinium spp., A.? minutum s.l. and cysts of Polykrikos spp., including two Arctic morphotypes. Assemblage III in the North Water polynya exclusively comprises A.? minutum s.l. and Brigantedinium spp. Assemblage IV in Baffin Bay is dominated by O. centrocarpum s.l. and Spiniferites spp., with Brigantedinium spp. on the shelves. The ratio of gonyaulacoid to protoperidinioid cysts (G : P) generally decreases with increased sea-ice cover, but it may also decrease in river plumes and in polynyas.

Spatial distribution of benthic foraminiferal stable isotopes and dinocyst assemblages in surface sediments of the Trondheimsfjord, central Norway

“…Halodinium minor has been previously reported from polar environments by Mudie (1992) and from warm to temperate environments in Australian estuaries by McMinn (1991). Matthiessen (1995) found high relative abundances at the Greenland and Iceland shelf with a random occurrence in the central Greenland Sea and the Norwegian Sea.…”

“…Cyst assemblages in coastal environments are usually tolerant to a wide range of temperatures and salinities and reflect more distinctive ecological preferences such as oceanic versus coastal waters, nutrient availability, salinity gradients as well as stress tolerance to rapid and periodic changes (e.g. Mudie, 1992;Dale et al, 2002;Harland et al, 2004;Radi et al, 2007;and Price and Pospelova, 2011). Dinoflagellate cysts are composed of highly resistant refractory organic matter and generally well preserved in sediments.…”

“…Radiosperma corbiferum has been recorded in high concentrations from the Baltic Sea, the Barents Sea (Sorrel et al, 2006 and references therein) and the Laptev Sea (Matthiessen, 1995;Kunz-Pirrung, 1999, 1998Sorrel et al, 2006;Price and Pospelova, 2011). Hexasterias problematica is a Prasinophyceae species (Parke and Dixon, 1964;Price and Pospelova, 2011) and has been recorded from Baffin Bay fjords by Mudie (1992) and in the North Sea region by Cleve (1900). These palynomorphs are linked to low saline/brackish cold surface waters in a marine environment with proximity to river inlets and/or melt water plumes (Matthiessen, 1995;Kunz-Pirrung, 1998;Sorrel et al, 2006;Price and Pospelova, 2011).…”

rRNA and rDNA based assessment of sea ice protist biodiversity from the central Arctic Ocean

“…Again, this might indicate either a lower degree of metabolic activity or a high degree of dormancy of these taxa (Jones & Lennon, 2010). During immediate microscopic investigations, we found many dinoflagellate cysts (data not shown), which are known to be present in Arctic waters (Harland et al, 1980;Mudie & Rochon, 2001;Potvin et al, 2013) at unfavourable conditions. Other studies also found a very high amount of Alveolata (alveolates) in their DNA libraries (Massana & Pedros-Alio, 2008;Not et al, 2009), although they were not investigating the rRNA library.…”

Quantitative reconstruction of sea-surface conditions over the last 150 yr in the Beaufort Sea based on dinoflagellate cyst assemblages: the role of large-scale atmospheric circulation patterns

“…Dinocysts are particularly useful microfossils in high latitudes because they are especially sensitive to sea-surface conditions in Arctic and sub-Arctic areas (e.g. Kunz-Pirrung, 2001;Matthiessen et al, 2005;Mudie and Rochon, 2001;Radi et al, 2001;de Vernal et al, 2001de Vernal et al, , 2005. Furthermore, dinocysts are preferentially preserved in environments like the Mackenzie Trough where sediment accumulation rates are relatively high, which prevents oxidation.…”