Application of the dry and wet biomass of bryophytes for phytoremediation of metals: Batch experiments

Abstract

The environmental contamination by metals is a concerning problem, especially when considering the characteristics of bioaccumulation and biomagnification of these elements. Once present in the water, metals are easily accrued by organisms and they can reach superiors trophic levels, including humans. This article aimed to investigate the potential of three species of aquatic and wetland bryophytes: Bryum muehlembeckii Bruch & Schimp., Ricciocarpos natans (L.) Corda and Sphagnum perichaetiale Hampe, in the removal of iron and chromium in synthetic aqueous samples, allowing the applicability of the technique in contaminated natural and residual water. Hence, the species were collected, cultivated in aquariums, and separately, they were kept at room temperature with natural light. As for the experiments, the species were exposed in the forms of dry and wet biomass to contaminated water samples with two different concentrations of metals. The concentrations of metals in the water were quantified before the experiments and after the exposure time of the tests, through the flame atomic absorption spectrometry. The removal of 97 and 95 % of iron and chromium were respectively achieved by using dry biomass of the three analyzed species. The ability to remove pollutants was shown to be species-dependent when using wet biomass. Among the investigated species, S. perichaetiale presented greater efficiency in removing pollutants. Therefore, the use of the tested species in dry and wet biomass forms are viable and, the same can be applied as phytoremediators agents and natural absorbents of metals to lentics environments of freshwater and effluents.