Seasonality of Dissolved Rare Earth Elements in the Lower Mississippi River

摘要: [1] Dissolved rare earth element (REE) concentrations were determined in a 27-month time series of the lower Mississippi River. Overall, results agree with limited previous investigations; that is, river shows enrichment heavy REEs relative to light and also has significant Ce anomaly. However, investigations relied on only single samples from river. This seasonal investigation reveals temporal variations river's REE chemistry. In particular, large (approximately fivefold) are observed. The follow seasonality similar particle-reactive trace elements. Also, anomaly corresponding greatest fractionation when dissolved lowest. encompassed period extreme flooding U.S. Midwest. this event did not appear affect concentrations. study compatible observations elements River which suggested importance redox processes within system controlling concentration variability for many these Additionally, speciation modeling indicates carbonate complexes likely dominate solution chemistry Mississippi. observed behavior is likewise speciation.