About RCEC
Faculty/Staff
Education/Visiting/Others
Hsieh, Chih-Chiang謝志強
Postdoctoral Research Fellow
Research Interests
The focus of my research is to estimate the source contributions of the bioavailable aerosol metals into the surface water of the Northwestern Pacific Ocean. The East China Sea (ECS) is located at the downwind side of mainland China, a major aerosol source to the global ocean. The ECS receives a large amount of aerosols mixed with relatively fine anthropogenic aerosols and coarse lithogenic dust. Aerosols are a major source of biologically essential dissolved trace metals (e.g., Fe, Co, Cu, Zn, Ni) in the euphotic zone of the ocean, deciding the growth and composition of different phytoplankton groups in the marine euphotic zone and thus influencing material cycling in the ocean. However, it is highly challenging to define the bioavailable aerosol metal fraction. My goal is to find the most realistic leaching protocol for the field and model studies and improve and get more accurate aerosol metals flux estimates (especially for Fe) into ocean.
Representative Publications
Hsieh, C.-C, Chen-Feng You, C.-F., and Ho, T.-Y. *, The solubility and deposition flux of East Asian aerosol metals in the East China Sea: The effects of aeolian transport processes, Marine Chemistry, 2023, 104268, ISSN 0304-4203, DOI: 10.1016/j.marchem.2023.104268.
Wu, H.-Y., Hsieh, C.-C., and Ho, T.-Y. *, Trace metal dissolution kinetics of East Asian size-fractionated aerosols in seawater: The effect of a model siderophore, Marine Chemistry, Volume 254, 2023, 104277, ISSN 0304-4203, DOI: 10.1016/j.marchem.2023.104277.
Hsieh, C.-C., Chen, H.-Y. and Ho, T.-Y. *, The effect of aerosol size on Fe solubility and deposition flux: A case study in the East China Sea. Marine Chemistry, 2022, 241 DOI: 10.1016/j.marchem.2022.104106.
Research
Estimates of bioavailable aerosol metals In the global field of oceanography, the estimation of bioavailable aerosol metals typically relies on dissolution methods using either ultrapure water or ammonium acetate buffer with a pH of approximately 4.7. However, my research has revealed that both of these methods are not suitable for natural environments, especially the ultrapure water dissolution method, which tends to underestimate the aerosol metal solubilities for Fe, Al, Ti, and V. Finding the optimal method for estimating bioavailable aerosol metals is a key focus of my future efforts!
The flux contribution of anthropogenic aerosol Fe into the Northwestern Pacific Ocean Recent studies have shown that anthropogenic aerosols are an important source of soluble iron in the Northwestern Pacific Ocean. However, through my research on aerosol and suspended particulate iron isotopic composition, I have found that in the surface waters of the Northwestern Pacific Ocean, natural dusts remain the primary supplier of bioavailable aerosol iron!
