Comparison of the Phytoplankton Assemblages of the South-Eastern Barents Sea and South-Western Kara Sea: Phytogeographical Status of the Regions

1999 ◽  
Vol 42 (2) ◽  
Author(s):  
N. V. Druzhkov ◽  
P. R. Makarevich
Keyword(s):  
Barents Sea ◽  
Kara Sea ◽  
The South ◽  
Phytoplankton Assemblages ◽  
South Eastern

Holocene climatic and palaeoenvironmental changes in the South-Eastern Barents Sea – new insights from palaeomagnetic and geochemical stratigraphy

2020 ◽  
Author(s):  
Martin Klug ◽  
Karl Fabian ◽  
Jochen Knies ◽  
Valérie Bellec ◽  
Leif Rise
Keyword(s):  
North Atlantic ◽  
Remanent Magnetization ◽  
Late Holocene ◽  
Environmental Changes ◽  
Barents Sea ◽  
Marine Ecosystem ◽  
Planetary Science ◽  
Coastal Current ◽  
The South ◽  
South Eastern

<p>Holocene climate variability and environmental changes have been studied using a sediment record from the Barents Sea with focus on the spatio-temporal evolution of bio-productivity and terrestrial sediment deposition in response to changes of climate and regional oceanography. From a 3 m long sediment core recovered in the South-Eastern Barents Sea at 72.5°N 32.5°E u-channels were extracted and stepwise demagnetized and measured for their natural remanent magnetization (NRM) and anhysteretic remanent magnetization (ARM) at the cryogenic magnetometer facility at the Geological Survey of Norway. The u-channel measurements at 3 mm resolution allow the reconstruction of palaeoinclination, relative declination and relative palaeointensity. Comparison of these parameters to FENNOSTACK (Snowball et al., 2007) and EGLACOM-SVAIS (Sagnotti et al., 2011) establishes a robust age model for the sediment sequence which otherwise contains little datable material. We applied statistical factor analysis as centred logratio (clr) transformation to reduce dimensionality of the XRF data and compare changes in high-resolution magnetic susceptibility, wet bulk density and XRF elemental composition with changes of climate proxies in other North Atlantic sedimentary records.</p><p>Based on the new chronostratigraphic framework changes of inorganic and organic proxies at long-term and sub-millennial scale resolve the temperature variability throughout the Holocene. Calcium content changes are related to regional bio-productivity changes in response to surface temperature changes with a pronounced deterioration at the beginning of the Neoglaciation and gradual enhancement during the late Holocene. Besides palaeoclimatic responses, the results offer the opportunity to study sediment transport and deposition during the regional deglaciation and mid-Holocene glacier growth in northwestern Fennoscandia. The temporal changes of the regional oceanography and the variability of marine palaeoproductivity in the South-Eastern Barents Sea indicate an active interplay between the North Atlantic Current (NAC) and the Norwegian Coastal Current (NCC) during the early Holocene, a predominance of the NCC during middle Holocene and a re-amplification of the NAC during the late Holocene. Comparison to other records from the Nordic Seas enables the reconstruction of responses and the vulnerability of this arctic marine ecosystem to past climate variations and may help to estimate upcoming responses to recent and future climate changes.</p><p> </p><p>References:</p><p>Snowball, I., L. Zillén, A. Ojala, T. Saarinen, and P. Sandgren (2007), FENNOSTACK and FENNORPIS: Varve dated Holocene palaeomagnetic secular variation and relative palaeointensity stacks for Fennoscandia, Earth and Planetary Science Letters, 255, (1-2), 106–116</p><p>Sagnotti, L., P. Macrì, R. Lucchi, M. Rebesco, and A. Camerlenghi (2011), A Holocene paleosecular variation record from the northwestern Barents Sea continental margin, Geochemistry, Geophysics, Geosystems, 12, (11)</p>

Distribution of phytoplankton community in Kotor Bay (south-eastern Adriatic Sea)

2012 ◽  
Vol 7 (3) ◽  
pp. 470-486 ◽  
Author(s):  
Dragana Drakulović ◽  
Branka Pestorić ◽  
Mirko Cvijan ◽  
Slađana Krivokapić ◽  
Nenad Vuksanović
Keyword(s):  
Phytoplankton Community ◽  
Adriatic Sea ◽  
Sampling Period ◽  
Single Species ◽  
Chemical Parameters ◽  
The South ◽  
Phytoplankton Assemblages ◽  
South Eastern ◽  
Physico Chemical ◽  
Shallow Coastal Area

AbstractThe goal of this paper was to explain variability of phytoplankton in a shallow coastal area in relation to physico-chemical parameters. Temporal variability and composition of phytoplankton were investigated in the Kotor Bay, a small bay located in the south-eastern part of the Adriatic Sea. Samplings were performed weekly from February 2008 to January 2009 at one station in the inner part of the Kotor Bay, at five depths (0 m, 2 m, 5 m, 10 m, 15 m). Phosphates, nitrites and nitrates ranged from values under the level of detection to the maximum values of 1.54, 1.53 and 23.91 µmol l−1, respectively. The phytoplankton biomass — represented by chlorophyll a concentration — ranged from 0.12 to 6.78 mg m−3, reaching a maximum in summer. Diatoms were present throughout the whole sampling period, reaching the highest abundance in March (3.42×105 cells l−1at surface). The peak of dinoflagellates in July (2.2×106 cells l−1 at surface) was due to a single species, Prorocentrum micans. The toxic dinoflagellate Dinophysis fortii occurred at a concentration of 2140 cells l−1 in May. The present results of phytoplankton assemblages and distribution provide valuable information for this part of the south-eastern Adriatic Sea where data is currently absent.

Plant communities with Arenaria pseudofrigida (Ostenf. et Dahl) Juz. ex Schischk. on islands of the south-eastern part of Barents Sea

2013 ◽  
pp. 78-85 ◽  
Author(s):  
N. V. Matveyeva ◽  
O. V. Lavrinenko ◽  
I. A. Lavrinenko
Keyword(s):  
Plant Communities ◽  
Barents Sea ◽  
The South ◽  
South Eastern ◽  
The Barents Sea ◽  
Marine Terraces

The plant communities with Arenaria pseudofrigida are common on the cobble-loam grounds on the edges of marine terraces on the Vaigach, Dolgiy and few smaller islands in the south-eastern part of the Barents Sea. These communities influenced by sea salty spray are described within 4 new synataxa (2 associations and 2 subassociations). They are provisionally placed within the alliance Arenarion norvegicae Nordh. 1935. order Thlaspietalia rotundifolii Br.-Bl. in Br.-Bl. et Jenny 1926, class Thlaspietea rotundifolii Br.-Bl. 1948.

scholarly journals A lithosphere-scale structural model of the Barents Sea and Kara Sea region

2014 ◽  
Vol 6 (2) ◽  
pp. 1579-1624 ◽  
Author(s):  
P. Klitzke ◽  
J. I. Faleide ◽  
M. Scheck-Wenderoth ◽  
J. Sippel
Keyword(s):  
Structural Model ◽  
Barents Sea ◽  
Kara Sea ◽  
High Density ◽  
The South ◽  
The West ◽  
Density Anomaly ◽  
The Barents Sea ◽  
Early Cenozoic ◽  
Oceanic Domain

Abstract. The Barents Sea and Kara Sea region as part of the European Arctic shelf, is geologically situated between the Proterozoic East-European Craton in the south and early Cenozoic passive margins in the north and the west. Proven and inferred hydrocarbon resources encouraged numerous industrial and academic studies in the last decades which brought along a wide spectrum of geological and geophysical data. By evaluating all available interpreted seismic refraction and reflection data, geological maps and previously published 3-D-models, we were able to develop a new lithosphere-scale 3-D-structural model for the greater Barents Sea and Kara Sea region. The sedimentary part of the model resolves four major megasequence boundaries (earliest Eocene, mid-Cretaceous, mid-Jurassic and mid-Permian). Downwards, the 3-D-structural model is complemented by the top crystalline crust, the Moho and a newly calculated lithosphere-asthenosphere boundary (LAB). The thickness distribution of the main megasequences delineates five major subdomains differentiating the region (the northern Kara Sea, the southern Kara Sea, the eastern Barents Sea, the western Barents Sea and the oceanic domain comprising the Norwegian-Greenland Sea and the Eurasia Basin). The vertical resolution of five sedimentary megasequences allows comparing for the first time the subsidence history of these domains directly. Relating the sedimentary structures with the deeper crustal/lithospheric configuration sheds some light on possible causative basin forming mechanisms that we discuss. The newly calculated LAB deepens from the typically shallow oceanic domain in three major steps beneath the Barents and Kara shelves towards the West-Siberian Basin in the east. Thereby, we relate the shallow continental LAB and slow/hot mantle beneath the southwestern Barents Sea with the formation of deep Paleozoic/Mesozoic rift basins. Thinnest continental lithosphere is observed beneath Svalbard and the NW Barents Sea where no Mesozoic/early Cenozoic rifting has occurred but strongest Cenozoic uplift and volcanism since Miocene times. The East Barents Sea Basin is underlain by a LAB at moderate depths and a high-density anomaly in the lithospheric mantle which follows the basin geometry and a domain where the least amount of late Cenozoic uplift/erosion is observed. Strikingly, this high-density anomaly is not present beneath the adjacent southern Kara Sea. Both basins share a strong Mesozoic subsidence phase whereby the main subsidence phase is younger in the South Kara Sea Basin.

scholarly journals Satellite ice extent, sea surface temperature, and atmospheric methane trends in the Barents and Kara Seas

2018 ◽  
Author(s):  
Ira Leifer ◽  
F. Robert Chen ◽  
Thomas McClimans ◽  
Frank Muller Karger ◽  
Leonid Yurganov
Keyword(s):  
Sea Ice ◽  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Barents Sea ◽  
Mixed Layer Depth ◽  
Kara Sea ◽  
Sea Surface ◽  
The South ◽  
The Barents Sea ◽  
Barents And Kara Seas

Abstract. Over a decade (2003–2015) of satellite data of sea-ice extent, sea surface temperature (SST), and methane (CH4) concentrations in lower troposphere over 10 focus areas within the Barents and Kara Seas (BKS) were analyzed for anomalies and trends relative to the Barents Sea. Large positive CH4 anomalies were discovered around Franz Josef Land (FJL) and offshore west Novaya Zemlya in early fall. Far smaller CH4 enhancement was found around Svalbard, downstream and north of known seabed seepage. SST increased in all focus areas at rates from 0.0018 to 0.15 °C yr−1, CH4 growth spanned 3.06 to 3.49 ppb yr−1. The strongest SST increase was observed each year in the southeast Barents Sea in June due to strengthening of the warm Murman Current (MC), and in the south Kara Sea in September. The southeast Barents Sea, the south Kara Sea and coastal areas around FJL exhibited the strongest CH4 growth over the observation period. Likely sources are CH4 seepage from subsea permafrost and hydrate thawing and the petroleum reservoirs underlying the central and east Barents Sea and the Kara Sea. The spatial pattern was poorly related to seabed depth. However, the increase in CH4 emissions over time may be explained by a process of shoaling of strengthening warm ocean currents that would also advect the CH4 to areas where seasonal deepening of the surface ocean mixed layer depth leads to ventilation of these water masses. Continued strengthening of the MC will further increase heat transfer to the BKS, with the Barents Sea ice-free in ~ 15 years. We thus expect marine CH4 flux to the atmosphere from this region to continue increasing.

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