
TY  - JOUR
A1  - Jeffree, RA 
A1  - Markich, SJ 
A1  - Brown, PL 
T1  - Comparative accumulation of Alkaline-earth metals by two freshwater Mussel species from the Nepean River, Australia: Consistences and a resolved Paradox
JF  - Marine and Freshwater Research
JO  - Mar. Freshwater Res.
Y1  - 1993
VL  - 44
IS  - 4
SP  - 609
EP  - 634
KW  - 
UR  - https://doi.org/10.1071/MF9930609 
N2  - Whole tissue concentrations of Be, Mg, Ca, Sr, Ba and 226Ra were determined in Hyridella depressa  (Lamarck) and Velesunio ambiguus (Philippi) from a minimally polluted region in the Upper Nepean River,  New South Wales. Although the mean tissue concentrations of each metal were comparable between the  two species, their patterns of accumulation were dissimilar. For each metal, tissue concentration was  significantly correlated (P&#8804;0.01) with tissue dry weight and shell length in H. depressa, but not in V. ambiguus, in which variability between individuals was high and Mg concentration was inversely correlated (P&#8804;0.05)  with tissue dry weight. However, in each species the Ca concentration was a highly significant (P&#8804;0.001)  positive predictor of the concentration of each of the other metals. For each species, normalized rates of  accumulation of the metals, relative to increasing Ca concentration and/or size, were 226Ra >Ba&#8805;Sr>Ca > Mg; these rates were inversely related (P&#8804;0.05) to their solubilities as hydrogen phosphates. This inverse  relationship was used to predict a solubility constant for BeHPO4. The results were consistent with those  previously obtained for V. angasi (Sowerby). The metal solubility relationships, based on the relative  increases in the tissue concentrations of each metal over the range of Ca concentrations, held for both species  even though V. ambiguus showed no significant (P>0.05) increase in tissue concentrations with size.  This paradox can be explained as follows. In both species the Ca tissue concentration is a measure of the  total influx and efflux of Ca and its analogues through the tissue of an individual over its lifetime; however,  in V. ambiguus this total flux is unrelated to mussel size. The use of Ca concentration to predict concentrations  of the other metals was effective in explaining up to 98% and 95% of the variability between individual mussels  of H. depressa and V. ambiguus respectively. Hence, the problem of inherent variability between individuals  can be eliminated. This will permit any spatial and/or temporal differences in the tissue concentrations of  alkaline-earth metals of mussel populations to be more readily discerned. 
ER  -

