Abstract
The concentration of 11 trace elements, plus Ca, Mg, Na and K was measured in moss bags of living and dead (oven-dried at 105°C) Platyhypnidium riparioides after a 1-week exposure to tap water, and to 0.21, 1.0, 2.5 and 4.0 μM solutions under laboratory conditions, with the aim of (1) observing the accumulation curves and (2) performing a statistical comparison in element concentrations. Uptake occurred both in living and in dead mosses following similar patterns in the two materials: a linear uptake was observed for Cd and Ni, a saturation curve for As, Cu, Hg and Pb, an unclear trend for Al and Mn and a trend leading to a maximum for Cr and Fe. An evident efflux of K indicated alterations in cell membrane permeability in living mosses and cellular damage in dead mosses. Living mosses accumulated higher concentrations of Cr (+4/+49%) and Mn (+124/+216%), while dead mosses accumulated higher concentrations of Cd (+13/+50%), Cu (+26/+51%), Ni (+22/+139%) and Zn (+22/+63%). Dead mosses maintained a considerable uptake efficiency for several trace elements, and sometimes even increased it as compared with living mosses, thus proving to be suitable for standard kits.
Acknowledgements
The authors are grateful to the Province of Vicenza, AATO Bacchiglione and ATO Brenta for funding. They also thank the collaboration, efficiency and expertise of the ARPAV laboratory of Bassano del Grappa and its personnel who made this work possible. Special thanks to Dr. Elena Pittao for data elaboration support, to Dr. Marcello Volpe who provided the peristaltic pump and to Dr. Elena Dalla Rosa for her laboratory support.