Accumulation of Cs by Carnivorous Aquatic Macrophytes (Utricularia spp.) on the Savannah River Site.

Plants are an important mode of transfer of contaminants from sediments into food webs. In aquatic ecosystems, contaminant uptake by macrophytes can vary by path of nutrient uptake (roots vs. absorption from water column). Carnivorous plants likely have additional exposure through consumption of small aquatic organisms. This study expanded on previous research suggesting that bladderworts (Genus Utricularia) accumulate radiocesium (Cs) and examined for (1) a potential association between sediment and plant concentrations and (2) differences in Cs accumulation among rooted and free floating Utricularia species. A strong correlation was found between average Cs concentrations in all Utricularia species (combined) and sediments (r = 0.9, p = 0.0374). Among three bladderwort species at common sites, Utricularia floridana, the only rooted species, had higher mean Cs concentrations than Utricularia purpurea, and U. purpurea had a greater mean Cs concentration than Utricularia inflata.