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Abstract We have carried out studies to examine the possibility of using biosorbents: the epigeic mosses Pleurozium schreberi (Willd. ex Brid.) Mitt., and the epiphytic lichens Hypogymnia physodes (L.) Nyl. in active biomonitoring of heavy metal pollution of surface waters. The dried sea algae Palmaria palmata (L.) Weber & Mohr were used as the third biosorbent. The studies were conducted in the waters of the Turawa Reservoir, a dam reservoir with a significant level of eutrophication in south-western Poland. Incremental concentrations of Mn, Ni, Zn, Cu, Cd, and Pb were determined in the exposed samples. It was shown that a 2-h exposure period increases the concentration of some metals in the exposed samples, even by as much as several hundred percent. High increments of nickel concentrations in the algae Palmaria palmata (mean: 0.0040 mg/g, with the initial concentration of c 0

Abstract The effect of calcium carbonate on the removal efficiency of cations of the selected heavy metals Cu, Zn and Pb from aqueous solutions using various biosorbents (BS) was investigated under laboratory static conditions. The main mechanism of biosorption of heavy metal cations is ion exchange, whereas the reaction with calcium carbonate results in precipitation of poorly soluble carbonates and hydroxides of the examined heavy metals. Studies conducted under static conditions have shown that the effect of Cu and Zn cations removal from solutions is better when using a mixture of BS and CaCO3 as compared to the effect of process, in which these two components were used separately. Removal efficiency for Cu and Zn has been shown to increase from 20 to 50% depending on the BS used. For the removal of lead cations, a measurable effect is found only for biosorbents whose active centers are saturated with protons (improvement in removal efficiency by about 20%). A synergy effect in the flow system was also investigated. It was found that under the conditions of the experiment, the addition of powdered CaCO3, in a weight ratio of 1 g CaCO3: 15 g BS, increases the removal efficiency of all the metals studied by 20–30%. It has been shown that an important role in the process of heterophasic ion exchange is played by neutralization of protons—desorbed from the biosorbents—with hydroxide ions released into the solution by partial dissolution of CaCO3 and subsequent hydrolysis reaction.