Figure 5 - uploaded by Maciej Mateusz Telesiński
Content may be subject to copyright.
Plate presents light microscope micrographs. 1) High focus of Islandinium minutum (EDG 1). 2) High focus of Echinidinium karaense (EDG 1). 3) Mid focus of Dubridinium sp. with flagellar scar (HR 3). 4) High focus of Islandinium ? cezare (EDG 1). 5) Mid focus of Echinidinium sleipnerensis (EDG 1). 6) Mid focus of Brigantedinium simplex with typical flagellar scars (NAL 4). 7) High focus of Selenopemphix quanta (EDG 1). 8) Mid focus of cyst of Polarella glacialis (EDG 1). 9) High focus of cyst of Pentapharsodinium dalei (IS 1). All scale bars = 10 μm.
Source publication
![Figure 3 A: Total sedimentary concentrations [cysts g −1 ] of dinocysts...](profile/Maciej-Telesinski-2/publication/371995540/figure/fig3/AS:11431281175483181@1689750605389/A-Total-sedimentary-concentrations-cysts-g-1-of-dinocysts-at-each-station-B_Q320.jpg)
Due to the Arctic amplification effect, the Svalbard archipelago is an important area for studying the ongoing environmental changes. However, its marine ecosystem is extremely complex. In this study, we analyze modern assemblages of dinoflagellate cysts (dinocysts) and benthic foraminifera from surface sediment samples around Svalbard. We use mult...
Context in source publication
Citations
... Furthermore, it cannot be excluded that some thin-walled transparent Impagidinium spp. cysts have been missed during the counting (Telesiński et al., 2023). Dinocyst fluxes [cysts cm −2 yr −1 ] were calculated using absolute dinocyst abundances [cysts g −1 ], sedimentation rates [cm yr −1 ], and dry bulk density [g cm −3 ]. ...
... The dinocyst species Echnidinium karaense, together with cysts of Polarella glacialis, has recently been identified as a winter drift ice indicator in waters around Svalbard (Telesiński et al., 2023). As the latter species is virtually absent in core JM09-020 (Supplemental Material), Echinidinium karaense remains the only available dinocyst sea-ice indicator. ...
... After ~2 ka BP the total and autotrophic dinocyst abundance decreased, suggesting deteriorating surface water conditions, possibly due to the thickening of the sea-ice cover. Similarly, the abundance of Operculoidinium centrocarpum s.l., a cosmopolitan species whose high abundances in high northern latitudes are associated with AW dominance (Grøsfjeld et al., 2009;Rochon et al., 1999;Telesiński et al., 2023) reached a maximum around 2.3 ka BP but decreased sharply shortly thereafter, though remained higher than in the first half of the Holocene (Figure 2d). Furthermore, the relative percentage of O. centrocarpum s.l. ...
In high northern latitudes, the Middle to Late Holocene was a time of orbitally-induced atmospheric cooling. This led to increased sea-ice production in the Arctic Ocean and its export southward, a decrease in sea surface temperatures (SST), and glacier advances at least since 5-4 ka BP. However, the response of the ocean-climate system to decreasing insolation was not uniform. Our research shows that the sea-ice cover in the northwestern Barents Sea experienced a late response to Neoglacial cooling. We analyzed dinoflagellate cyst assemblages from a sediment core from Storfjordrenna, south of Svalbard. We found that the area experienced ice-free conditions throughout most of the Mid- and Late Holocene. It was only after 2.3 ka BP that the study site became covered with winter drift ice and primary productivity decreased subsequently. Other regional data support the decrease in SST, the expansion of the sea-ice cover, and the deterioration of the environmental conditions around that time. Our findings indicate that the sea-ice cover in the northwestern Barents Sea required a significant amount of time to respond to the general cooling trend in the region. These results have important implications for present-day environmental changes. Even if the current warming trend is revoked in the future, the observed sea-ice loss in the Barents Sea may be incredibly challenging to reverse.
Over the last four decades, organic-walled dinoflagellate cysts have shown high potential as tracers of past sea-surface conditions during the Quaternary. These microfossils relate to the pelagic productivity of both phototrophic and heterotrophic protist organisms and are recovered in high numbers in almost all marine environment settings from the nearshore and estuarine systems to the distal continental margin. In polar environments, where other conventional proxies are rare or absent, dinoflagellate cysts showed a relatively high diversity of species and a close relationship with sea-ice cover duration, winter and summer temperature, and salinity, enabling quantitative reconstructions of several oceanic variables over time. From the temperate to the tropical latitudes of the Atlantic Ocean, their modern distribution highlights a response to primary productivity and seasonal contrasts in surface temperature. They also have proven that they could be used as tracers of eutrophication in stratified systems and can also highlight human impact on their distribution. In this paper, we present an overview of dinoflagellate cysts as ecological tracers in recent and past sediments of the Atlantic Ocean, from the Arctic to the Antarctic. We provide examples of their use as proxies in paleoclimatic-palaeoceanographic studies at glacial to interglacial time scales, with emphasis on the last ice age to recent (last 25 kyr), the northern North Atlantic and western-eastern tropic North Atlantic. We also discuss their potential as tracers of anthropogenic stress in coastal environments.
In high northern latitudes, the Middle to Late Holocene was a time of orbitally-induced atmospheric cooling. This led to increased sea-ice production in the Arctic Ocean and its export southward, a decrease in sea surface temperatures (SST), and glacier advances at least since 5-4 ka BP. However, the response of the ocean-climate system to decreasing insolation was not uniform. Our research shows that the sea-ice cover in the northwestern Barents Sea experienced a late response to Neoglacial cooling. We analysed dinoflagellate cyst assemblages from a sediment core from Storfjordrenna, south of Svalbard, and found that the area experienced ice-free conditions throughout most of the Mid- and Late Holocene. It was only after 2.3 ka BP that the study site became covered with winter drift ice and primary productivity decreased subsequently. Other data from the region support the decrease in SST, the expansion of the sea-ice cover, and the deterioration of the environmental conditions around that time. Our findings indicate that the sea-ice cover in the northwestern Barents Sea required a significant amount of time to respond to the general cooling trend in the region. These results have important implications for present-day environmental changes. Even if the current warming trend is revoked in the future, the observed sea-ice loss in the Barents Sea may be incredibly challenging to reverse.
