Trace element uptake assessment in the planktonic biofiltration system
The concentration of trace elements (Fe, Mn, Cr, Co, Ni, Cu, Pb, Cd, As) through the planktonic food chain of the White Sea have been studied by the experimental approach. The experiment included zooplankton sampled in a reference area feeding on a seston contained the different trace metals concentrations. Seston sampled in the st. Chupa was enriched by Fe, Cu, Pb, Cr, Co, As, and Ni comparing to the seston from st. Kartesh (reference area). The differences in the concentrations of the suspended particular matter and of the indicator elements of a terrigenous admixture (Al, Ti, Zr) evidence on higher natural background of the trace metals’ content in the seston from st. Chupa due to higher contribution of the minerals. Zooplankton that fed on the seston characterised by higher trace elements’ content has accumulated Fe, Mn, and Cr, at a less degree, Ni, Co, Pb, and Cu; particularly, these were the elements which content were high in seston. Despite Mn content in seston did not differ between two treatments, this element was accumulated by the zooplankton, but had low content in faecal pellets. This tells about the highest Mn assimilation by the zooplankton; this element may become the most bioavailability. When comparing the trace element content between the seston and the faecal pellets, the concentrations of the most elements in faecal pellets are lower comprising as low as Zn - 72%; Mn - 24; Cu - 97; Pb - 62; Cr - 99; Co - 78; Ni - 87; As - 96; Cd - 65% of the concentration in the seston.