Research Interest(s)
My research focuses on the biogeochemistry of trace metals in polar and open ocean systems, with a particular emphasis on the cycling of bioactive metals and their role in regulating marine productivity. Trained as a chemical oceanographer with an interdisciplinary background, I work at the interface of marine geochemistry and physical oceanography, combining geochemical observations with an understanding of ocean circulation and ecosystem processes.
A central focus of my research is the role of Antarctic margins – including continental shelf sediments, glacial systems, and marine ice – in supplying trace metals to the Southern Ocean. By combining measurements of trace metal concentrations and isotopic compositions with hydrographic observations, I investigate how biogeochemical processes shape trace metal distributions and how they are transported across continental shelves and into the open ocean. Through these approaches, I aim to better constrain the sources, transport pathways, and fate of trace metals in the ocean, and to understand how changing oceanographic conditions may influence nutrient supply and marine ecosystems in a changing climate.
Beyond research, I value interdisciplinary collaboration and actively contribute to scientific exchange within both the oceanographic community and the broader public. I currently serve as a member of the Early Career Scientist Committee of the International GEOTRACES Program and as part of the Early Career Representative team in the EGU Ocean Sciences Division.
Current project:
MiningImpact 3 – Assessing the environmental impacts of deep-sea mining of polymetallic nodules and seafloor massive sulphides
MetSpec – Trace metals and their speciation and biogeochemical processes in manganese nodule areas after the collector test
Google scholar: https://scholar.google.com/citations?user=bUAzYUQAAAAJ&hl=en
Linkedin: https://www.linkedin.com/in/hatian/
Publications:
- Tian, H.-A., van Manen, M., Bunnell, Z. B., Reichart, G.-J., Conway, T. M., & Middag, R. (2026). Iron isotope constraints on source and transport of sediment-derived dissolved Fe in the Weddell Sea region. Geochimica et Cosmochimica Acta. doi:https://doi.org/10.1016/j.gca.2026.01.033
- Tian, H.-A., Manen, M. v., Eich, C., Jung, J., Poll, W. H. v. d., Reichart, G.-J., Conway, T. M., & Middag, R. (2025). Dissolved zinc and cadmium isotope systematics in the Amundsen and Weddell coastal Antarctic marginal seas. Geochimica et Cosmochimica Acta, 399, 93-110. doi:https://doi.org/10.1016/j.gca.2025.04.017
- Eich, C., van Manen, M., McCain, J. S. P., Jabre, L. J., van de Poll, W. H., Jung, J., Pont, S. B. E. H., Tian, H. A., Ardiningsih, I., Reichart, G. J., Bertrand, E. M., Brussaard, C. P. D., & Middag, R. (2024). Temperature-enhanced effects of iron on Southern Ocean phytoplankton. EGUsphere, 2024, 1-45. doi:https://doi.org/10.5194/egusphere-2024-1508
- Tian, H.-A., van Manen, M., Bunnell, Z. B., Jung, J., Lee, S. H., Kim, T.-W., Reichart, G.-J., Conway, T. M., & Middag, R. (2023). Biogeochemistry of iron in coastal Antarctica: isotopic insights for external sources and biological uptake in the Amundsen Sea polynyas. Geochimica et Cosmochimica Acta, 363, 51-67. doi:https://doi.org/10.1016/j.gca.2023.10.029
- Tian, H.-A., van Manen, M., Wille, F., Jung, J., Lee, S., Kim, T.-W., Aoki, S., Eich, C., Brussaard, C. P. D., Reichart, G.-J., Conway, T. M., & Middag, R. (2023). The biogeochemistry of zinc and cadmium in the Amundsen Sea, coastal Antarctica. Marine Chemistry, 249, 104223. doi:https://doi.org/10.1016/j.marchem.2023.104223
- van Manen, M., Aoki, S., Brussaard, C. P. D., Conway, T. M., Eich, C., Gerringa, L. J. A., Jung, J., Kim, T.-W., Lee, S., Lee, Y., Reichart, G.-J., Tian, H.-A., Wille, F., & Middag, R. (2022). The role of the Dotson Ice Shelf and Circumpolar Deep Water as driver and source of dissolved and particulate iron and manganese in the Amundsen Sea polynya, Southern Ocean. Marine Chemistry, 246, 104161. doi:https://doi.org/10.1016/j.marchem.2022.104161
- Eich, C., Biggs, T. E. G., van de Poll, W. H., van Manen, M., Tian, H.-A., Jung, J., Lee, Y., Middag, R., & Brussaard, C. P. D. (2022). Ecological Importance of Viral Lysis as a Loss Factor of Phytoplankton in the Amundsen Sea. Microorganisms, 10(10). doi:https://doi.org/10.3390/microorganisms10101967
- Liao, W.-H., Takano, S., Tian, H.-A., Chen, H.-Y., Sohrin, Y., & Ho, T.-Y. (2021). Zn elemental and isotopic features in sinking particles of the South China Sea: Implications for its sources and sinks. Geochimica et Cosmochimica Acta, 314, 68-84. doi:https://doi.org/10.1016/j.gca.2021.09.013
- Takano, S., Liao, W.-H., Tian, H.-A., Huang, K.-F., Ho, T.-Y., & Sohrin, Y. (2020). Sources of particulate Ni and Cu in the water column of the northern South China Sea: Evidence from elemental and isotope ratios in aerosols and sinking particles. Marine Chemistry, 219, 103751. doi:https://doi.org/10.1016/j.marchem.2020.103751