Uptake and release of zinc by aquatic bryophytes (Fontinalis antipyretica L. ex. Hedw.)

• Tipo: Artigo em Revista Científica Internacional
• Data: 2002

Autores

Ramiro Martins (Autor) FEUP; R. A. R. Boaventura (Autor) FEUP

Revista

Título: Water Research

Vol. 36 Nº 20

Páginas: 5005-5012

ISSN: 0043-1354

Editora: Elsevier

Indexação

ISI Web of Knowledge - 31 Citações

Scopus - 38 Citações

Classificação Científica

FOS: Ciências da engenharia e tecnologias > Outras ciências da engenharia e tecnologias

Outras Informações

ID Authenticus: P-00H-FC3

DOI: 10.1016/s0043-1354(02)00233-6

Abstract (EN): 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 It 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 263 mg g(-1) (dry wt.). A first-order mass transfer kinetic model was fitted to the experimental data to determine the uptake and release constants, k(1) and k(2), the zinc concentration in mosses at the end of the uptake period, C-mu, and at the equilibrium, for the contamination and decontamination stages, C-me and C-mr respectively. A bioconcentration factor, BCF = k(1)/k(2) (zinc concentration in the plant, dry wt./zinc concentration in the water) was determined. A biological elimination factor defined as BEF = 1 - C-mr/C-mu was also calculated. BCF decreases from about 4500 to 2950 as Zn concentration in water increases from 1.05 to 3.80 mg 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.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 8