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Heavy metals sorption in lichen cationactive layer
|Andrzej Kłos 1, Małgorzata Rajfur 1, Witold Wacławek 2, Maria Wacławek 1|
1. Opole University, Chair of Technology (UO), ul. Kominka 4, Opole 45-032, Poland
Bioindicative properties of lichens were observed by William Nylander as early as in the 19th century. He noticed that some lichen species began to die out in Paris agglomeration and associated this fact with the increasing air pollution. Lichens, owing to their anatomy and peculiar mode of nutrition, accumulate substances contained in the air and precipitation. Air pollutants, depending on their type and concentration, build in the lichen texture and cause physiological and morphological changes or lead even to thallus destruction.
Studies described in the literature indicate that there is an interrelation between pollutant content of lichen thallus and its concentration in the environment. Problems related to study methodology standardisation stem from different climate conditions, type and composition of substratum on which lichens grow, as well as from airborne aerosol composition on studied areas. So far some have been studies conducted on the impact of these factors on sorption intensity. Heavy metals are the most frequently studied environment pollutants, as their presence in the natural environment indicates the pollution origin and intensity, as well as pollutant spreading directions.Previous studies demonstrate that heavy metal sorption in lichens occurs as the result of heterophase ion exchange between lichen cationactive layer and precipitation with which lichens contact. Building in of cations into lichen thallus texture is the parallel or secondary process. The aim of present studies is to investigate the impact of abiotic factors on coefficients of heavy metal cation distribution between the environment and lichen thallus. The impact of precipitation composition and temperature on the process course was examined among other things. Studied processes of sorption of heavy metals from solutions, in which lichens were dipped, were described by means of mathematic models of Langmuir and Freundlich isotherms.
Presentation: Poster at SMCBS'2005 Workshop, by Małgorzata Rajfur
See On-line Journal of SMCBS'2005 Workshop
Submitted: 2005-07-14 12:30 Revised: 2009-06-07 00:44