Utilize este identificador para referenciar este registo: http://hdl.handle.net/10198/2002
Título: Uptake and release of zinc by aquatic bryophytes (Fontinalis antipyretica L. ex. Hedw.)
Autor: Martins, Ramiro
Boaventura, Rui
Palavras-chave: Aquatic bryophytes
Mosses
Kinetics
Zinc
Fontinalis antipyretica
Data: 2002
Editora: Elsevier
Citação: 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
Resumo: 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.
URI: http://hdl.handle.net/10198/2002
ISSN: 0043-1354
Versão do Editor: http://www.sciencedirect.com/science/journal/00431354
Aparece nas colecções:DTQB - Artigos em Revistas Indexados ao ISI/Scopus

Ficheiros deste registo:
Ficheiro Descrição TamanhoFormato 
Dez 2002 Uptake and release of zinc by aquatic bryophytes (Fontinalis antipyretica L. ex. Hedw.) (meu).pdf165,01 kBAdobe PDFVer/Abrir


FacebookTwitterDeliciousLinkedInDiggGoogle BookmarksMySpace
Formato BibTex MendeleyEndnote Degois 

Todos os registos no repositório estão protegidos por leis de copyright, com todos os direitos reservados.