Annual variations of elemental quantities in brown sea algae hijiki Hizikia fusiforme.

Abstract

Quantitative variation of 12 elements such as K, Ca, Fe, Co, Cu, Zn, As, Br, Sr, Rb, I and Pb in a brown algae, hijiki, Hizikia fusiforme, was observed from June 1982 through July 1983, using simultaneous multi-element analysis of PIXE. The patterns of variation on the ele-mental concentration were found to be classified into three groups. Br and Sr were complex in their annual variation patterns, showing minimum values in Jan., Mar. and Aug., which may relate to the physiological aspects of the sea algae concerned. Though three hollows were also found for Ca, its variation was typical in demonstrating minimum values just after the respective harvestings by fishermen. Fe, Co, Cu, Rb and Pb were elements with peaks showing a maximum only in Aug., probably influenced by environmental causes such as atmospheric pollution or seasonal changes of tides and currents around the experimental area. No variation was found for the element K, which is considered as a main component of algae tissues. A similar pattern was observed for such element as As, which also behaves as essential elements in the algae tissue. Iodine showed an irregular variation pattern, presenting triple peaks during the period. How-ever, the corresponding hollows did not coincide with the results given by elements like Sr and Br, which had similar patterns. The ranges of the variations between maximum and minimum values had a factor of 2-3. Radioecologically, the differences may explain significance of the results as certain indicators, when submitting more precise radiation doses applying concentration factors for radionuclides released from nuclear facilities into the sea.