Trace metals in skeletal calcite of echinoderms from the Barents Sea.

This study investigates the skeletal accumulation of selected elements (Al, Ag, As, Ca, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Pb, Sr, Zn) in echinoderms inhabiting Barents Sea, an area impacted by human activities from northern Norway and Kola Peninsula, known sources of metal pollution. The primary aim was to have insight whether metals incorporation in the skeleton of Arctic echinoderms is regulated physiologically by the organism or influenced by abiotic environmental conditions (expressed as distance from the source of metal pollution). Metal concentrations were analysed in 17 species from four echinoderm classes: Asteroidea, Ophiuroidea, Crinoidea and Echinoidea.

Summer and winter MgCO levels in the skeletons of Arctic bryozoans.

In the Arctic, seasonal patterns in seawater biochemical conditions are shaped by physical, chemical, and biological processes related to the alternation of seasons, i.e. winter polar night and summer midnight sun.

Minor and trace elements in skeletons of Arctic echinoderms.

We report the ratios of minor (K/Ca, Na/Ca, P/Ca, S/Ca) and trace elements (Al/Ca, Ba/Ca, Fe/Ca, Mn/Ca and Zn/Ca) in skeletons of five Arctic echinoderm species representing three classes: Asteroidea, Ophiuroidea, Crinoidea. We found that skeletons of Arctic echinoderms show a unique, species-specific trace element composition that may suggest that incorporation of elements into the skeleton is biologically controlled by the organism. On the other hand, the concentration of some minor elements in skeletal parts exhibit patterns that are consistent with elemental concentrations in seawater, indicating that formation of echinoderm skeletons is environmentally controlled.

Variability in magnesium content in Arctic echinoderm skeletons.

In this study, 235 measurements of magnesium concentration in echinoderm's skeletons were compiled, including 30 species and 216 specimens collected from northern and western Barents Sea. We aimed to reveal the scale of Mg variation in the skeletons of Arctic echinoderms. Furthermore, we attempted to examine whether the Mg concentration in echinoderm skeletons is determined primarily by biological factors or is a passive result of environmental influences.