TY - CONF

T1 - Living on the edge: intertidal foraminifera at the 78°N, Central Spitsbergen

AU - Golikova, Elena

AU - Mikhailov, Dmitrii

AU - Voltski, Ivan

AU - Varfolomeeva, Marina

AU - Korsun, Sergei

PY - 2019

Y1 - 2019

N2 - Both the standing stock and taxonomic diversity of marginal marine foraminifera tend to decrease polewards (Lübbers, Schönfeld, 2018). Data on living assemblages of intertidal and salt marsh foraminifera from the subarctic are scarce and are almost absent from higher latitudes. Thus, the distribution limits of the littoral foraminifera to the north remains unknown. Here, we described living foraminiferal assemblages from the intertidal area of a non-glaciated Dicksonfjord in Central Spitsbergen (78°50´N, 15°24´E). Samples were collected along a 1.5 km transect on a mudflat towards the delta of glacio-fluvial river in the fjord head. The intertidal foraminiferal fauna of the Dicksonfjord was significantly depleted comparing to the temperate and subarctic latitudes; the absolute abundance of living foraminifera was extremely low (1–12 ind./10 cm3). The living assemblage was represented only by 3 species of elphidiids, among which Elphidium albiumbilicatum was dominant. Agglutinated species were completely absent. Our data support the idea of latitudinal decrease in species richness and densities of intertidal foraminifera to the north. Taxonomically, only elphidiids withstand the harsh intertidal environment of the Arctic fjord. Among Arctic and subarctic intertidal foraminifera, only elphidiids have an elaborate system of channels in the shell wall, which serves to deploy and withdraw pseudopodia quickly. These agile protists are able to dig upwards through quickly depositing mineral fines delivered by the turbid river or to burrow quickly into the sediment escaping fresh-water pulses during low tide.

AB - Both the standing stock and taxonomic diversity of marginal marine foraminifera tend to decrease polewards (Lübbers, Schönfeld, 2018). Data on living assemblages of intertidal and salt marsh foraminifera from the subarctic are scarce and are almost absent from higher latitudes. Thus, the distribution limits of the littoral foraminifera to the north remains unknown. Here, we described living foraminiferal assemblages from the intertidal area of a non-glaciated Dicksonfjord in Central Spitsbergen (78°50´N, 15°24´E). Samples were collected along a 1.5 km transect on a mudflat towards the delta of glacio-fluvial river in the fjord head. The intertidal foraminiferal fauna of the Dicksonfjord was significantly depleted comparing to the temperate and subarctic latitudes; the absolute abundance of living foraminifera was extremely low (1–12 ind./10 cm3). The living assemblage was represented only by 3 species of elphidiids, among which Elphidium albiumbilicatum was dominant. Agglutinated species were completely absent. Our data support the idea of latitudinal decrease in species richness and densities of intertidal foraminifera to the north. Taxonomically, only elphidiids withstand the harsh intertidal environment of the Arctic fjord. Among Arctic and subarctic intertidal foraminifera, only elphidiids have an elaborate system of channels in the shell wall, which serves to deploy and withdraw pseudopodia quickly. These agile protists are able to dig upwards through quickly depositing mineral fines delivered by the turbid river or to burrow quickly into the sediment escaping fresh-water pulses during low tide.

M3 - Abstract

SP - 29

EP - 30

Y2 - 1 July 2019 through 4 July 2019

ER -