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Authors
Advisor(s)
Abstract(s)
The zinc uptake and posterior release by an aquatic bryophyte—Fontinalis antipyretica L. Ex Hedw.—was
experimentally studied in laboratory exposing the plants to different zinc concentrations in the range, 1.0–5.0 mg l 1, for
a 144 h contamination period, and then exposed to metal-free water for a 120 h decontamination period. The
experiments were carried out in perfectly mixed contactors at controlled illumination, using mosses picked out in
February 1997, with a background initial zinc concentration of 263mg g 1 (dry wt.). A first-order mass transfer kinetic
model was fitted to the experimental data to determine the uptake and release constants, k1 and k2; the zinc
concentration in mosses at the end of the uptake period, Cmu; and at the equilibrium, for the contamination and
decontamination stages, Cme and Cmr; respectively. A bioconcentration factor, BCF ¼ k1=k2 (zinc concentration in the
plant, dry wt./zinc concentration in the water) was determined. A biological elimination factor defined as BEF ¼
1 Cmr=Cmu was also calculated. BCF decreases from about 4500 to 2950 as Zn concentration in water increases from
1.05 to 3.80mg l 1. BEF is approximately constant and equal to 0.80. Comparing Zn and Cu accumulation by
Fontinalis antipyretica, it was concluded that the uptake rate for Zn (145 h 1) is much lower than for Cu (628 h 1) and
the amount retained by the plant decreased by a factor of about seven.
Description
Keywords
Aquatic bryophytes Mosses Kinetics Zinc Fontinalis antipyretica
Citation
Martins, Ramiro; Boaventura, Rui (2002). Uptake and release of zinc by aquatic bryophytes (Fontinalis antipyretica L. ex. Hedw.). Water Research. ISSN 0043-1354. 36:20 p.5005-5012
Publisher
Elsevier