ISSN:
1365-2427
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
1. We studied stress responses and metal exchange (uptake and loss) kinetics in the aquatic moss Fontinalis antipyretica Hedw. following transplant (in plastic mesh bags) to clean and metal-contaminated river sites and under laboratory conditions.2. The stress response (estimated on the basis of chlorophyll:phaeophytin ratio) was more pronounced, and the moss took longer to recover, following transplant to heavily contaminated sites.3. Metal uptake over the 28 day exposure period was predicted well by a two-compartment kinetic model: uptake velocity was initially high and gradually declined, with metal concentration in the moss showing a tendency to reach an equilibrium with metal concentration in the water. Mean uptake rate, time to reach equilibrium and metal concentration in moss at equilibrium all increased with increasing metal concentration in the water.4. Bioconcentration constants calculated on the basis of our data rank the metals studied in the order Zn 〈 Ni 〈 Co 〈 Cu 〈 Pb 〈 Cd.5. Following retransplant of mosses to a clean site, metal loss was not predicted well by a passive exchange mode of the above type; instead, two phases (rapid and slow) were apparent. Loss rates during both phases, and proportion of metal load lost during the rapid phase, were proportional to the concentration of metal in the moss at the start of the recuperation trial.6. We present nomograms to allow estimation of severity of contamination on the basis of metal concentration in moss and duration of transplant.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-2427.1994.tb00876.x
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