Abstract
AbstractAlthough it is well established that microalgae take up metals and other contaminants from water and it has been suggested that algae may play a significant role in mobilizing sediment bound contaminants, there has been little research on the uptake of sediment‐associated contaminants by microalgae. This may be important for microphytobenthos, which is closely associated with sediments. We report on laboratory experiments investigating the uptake of cadmium (Cd) from sediment and water by Cylindrotheca closterium over 96 h. The role of microalgae in the partitioning of Cd between sediment and water was also investigated. While concentrations do not typically represent those in the natural environment, we showed C. closterium takes up Cd from sediment, and concentration in microalgae is affected by sediment organic matter content. Cylindrotheca closterium influenced Cd movement between sediment and water: transfer from water to sediment was slowed, while transfer from sediment to overlying water (all treatments) and interstitial water (unprocessed sediment treatments) was increased. This is the first article to describe Cd uptake by diatoms from intertidal sediment in relation to sediment properties and mobilization of Cd from sediment in the presence of diatoms. Microalgae may serve as a pathway for sediment‐associated metals to enter into aquatic food webs, and their presence appears to increase metal concentrations in water potentially making any mobilized metals available for uptake by other species. Given this and their importance as the basis of the food chain, there may be implications for environmental and human health and potential impacts for the biological stability of the sediment.
Highlights
Phytoplanktonic microalgae are well studied with respect to contaminant uptake from water
It has long been suggested that algae may play a significant role in mobilizing sediment bound metals (Laube et al 1979), there has been a dearth of research involving the uptake of contaminants from sediment to microphytobenthic algae (Stronkhorst et al 1994; Absil and van Scheppingen 1996)
There is some indication that contamination of pore water may increase over time (χ2 = 5.9, p = 5.3 × 10−2). This is the first report to describe differences in Cd uptake by diatoms from sediment, dependent on sediment properties, and the first to describe the mobilization of Cd from sediment in the presence of diatoms
Summary
Phytoplanktonic microalgae are well studied with respect to contaminant uptake from water It has long been suggested that algae may play a significant role in mobilizing sediment bound metals (Laube et al 1979), there has been a dearth of research involving the uptake of contaminants from sediment to microphytobenthic algae (Stronkhorst et al 1994; Absil and van Scheppingen 1996). The only known biological role of cadmium (Cd) is as a zinc (Zn) replacement at the catalytic site of carbonic anhydrase, reported in the marine diatom Thalassiosira weissflogii (Lane and Morel 2000) in a study which discovered a distinct Cd-specific form of carbonic anhydrase (CDCA). Cd is known to be damaging to the kidneys and to affect the bone metabolism and the cardiovascular system of mammals (Maret and Moulis 2013)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
