Influence of dissolved organic matter on rare earth elements and yttrium distributions in coastal waters

• Published in: Chemistry and ecology Vol. 26; no. 2; pp. 123 - 135
• Main Authors: Censi, P., Zuddas, P., Randazzo, L. A., Saiano, F., Mazzola, S., Aricò, P., Cuttitta, A., Punturo, R.
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 01.04.2010; Taylor & Francis Ltd
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Applied ecology; Biochemistry, Molecular Biology; Biological and medical sciences; Ce anomaly; Chlorophyll; chlorophyll-α; Ecotoxicology, biological effects of pollution; Fundamental and applied biological sciences. Psychology; General aspects; Life Sciences; Mediterranean Sea; rare earth elements; Sea water ecosystems; Synecology; Trace elements; Mediterranean Sea; MED, Italy, Sicilia, Palermo; MED, Central Mediterranean; Marine environment; Aquatic environment; Chlorophyll; Lanthanide; Dissolved organic matter; chlorophyll-α; rare earth elements; Anomaly; Coastal water; Ce anomaly; Mediterranean Sea; Coastal zone; chlorophyll
• ISSN: 0275-7540; 1029-0370
• DOI: 10.1080/02757541003627720

Data collected during this study indicate that dissolved Y and REE (rare earth element) behaviour can be monitored through shale-normalised ratios. Relationships occurring between these ratios suggest that leaching from lithogenic materials is the main source of REE in the studied area. This process involves riverine detrital matter in the inner area of the Gulf of Palermo. Features of shale-normalised patterns and the relationship recognised between dissolved Fe and Y/Ho suggest that REE are released from Fe-rich coatings of atmospheric dust. Observed similarities between dissolved Fe and chlorophyll-α content suggest that leaching of Fe-rich atmospheric particulates induces a fertilisation of shallow water layers influencing the dissolved organic content. In turn, the increasing chlorophyll-α content causes a progressive decrease in amplitude of the negative Ce anomaly in seawater that is also observed in water in the Central Mediterranean Sea, suggesting that organic matter generally plays a key role in REE behaviour at the solid-liquid interface. Shale-normalised REE features recognised in suspended particulate matter (SPM) indicate the occurrence of three different fractions from lithogenic matter, biogenic carbonates and authigenic components, respectively. The latter is formed during REE scavenging onto the surface of detrital biogenic particles and is mainly recognised in inner gulf waters.