Rinsing of seagrasses with distilled water is often carried out prior to element analysis. The present study shows that such rinsing of the leaves of the Mediterranean seagrass Posidonia oceanica (L.) Delile results in significant element leakages, depending on leaf age. In adult leaves, only Fe concentrations are reduced. In younger leaves, significant concentration reductions occur for S, Mg, Na, Zn, Pb, Cd, Fe, Cr, and Ti, while concentrations of N, P, Ca, and Cu remain unaffected. C and K concentrations increase following distilled water rinsing owing to weight loss by leaching of Na and probably other major ions. The relative contribution of the different age classes to total shoot weight implies that distilled water rinsing also affects element analysis of whole shoots. The use of distilled water rinsing prior to element analysis should thus be avoided. |
