Yu (Swain) Wang | ALES Graduate Seminar

Event details: A graduate exam seminar is a presentation of the student’s final research project for their degree.
This is an ALES PhD Final Exam Seminar by Yu (Swain) Wang. This seminar is open to the general public to attend.

Zoom Link:  https://ualberta-ca.zoom.us/j/96245610951?pwd=OEdHcmZsc1ZkdklGMTVIbWJRbm0zdz09

PhD with Drs. William Shotyk and Chad Cuss

Thesis Topic: Challenges and Potential Solutions in Analyzing Trace Element Concentrations and Size distributions in Boreal Rivers and Peat Bog Waters

Abstract:

Trace elements (TEs) can exist in water in various forms including hydrolyzed ions, simple inorganic molecules, organic complexes, adsorbed onto inorganic and organic colloids, or incorporated into suspended particles. The mobility and bioavailability of TEs in natural waters highly depend on these forms. Advancements in size-based analytical techniques are enhancing our comprehension of the colloid-facilitated transport and environmental relevance of TEs in natural waters. Waters in boreal zones contain significant amounts of dissolved organic matter, inorganic colloids, or both, and exhibit a wide range of pH levels. These characteristics present analytical challenges for the accurate separation of dissolved TEs in such waters. Although size-based methods are commonly used for this purpose, they are constrained by potential artefacts in filtration process and AF4-UV-ICP-MS analysis, which limits the reliable analysis of naturally occurring colloids and their interactions with TEs. Potential solutions to mitigate these artefacts are discussed, which can help address experimental inconsistencies and improve the precision and accuracy of TE analysis. These studies presented in the thesis is critical for advocating the use of filtration and AF4-UV-ICP-MS methods to accurately evaluate the concentrations of dissolved trace elements at ultralow levels (i.e., ng L^-1) and within small size ranges (ca. < 20 kDa) in boreal waters.