Laodong Guo

School of Freshwater Sciences



Dr. Guo’s major research focus is on marine and freshwater biogeochemistry, with an emphasis on the role of natural organic matter and aquatic colloids/nanoparticles in governing the fate, transport and bioavailability of chemical species. He received his master degree in marine chemistry from Xiamen University, China, where he then worked for several years in the Department of Oceanography. After moving to Texas A&M University, College Station, where he obtained his Ph.D. degree in Chemical Oceanography in 1995, Dr. Guo worked as a postdoc and assistant research scientist in the Laboratory for Oceanographic and Environmental Research, Texas A&M University at Galveston, until 2000. He then moved to the University of Alaska-Fairbanks, and worked there for 5 years as scientist/research professor in the International Arctic Research Center. Dr. Guo joined the Department of Marine Science at the University of Southern Mississippi in 2005 as an associate professor and was granted tenure the following year and full professorship in 2011. He has been a professor in the School of Freshwater Sciences at the University of Wisconsin-Milwaukee since January 2012.

Dr. Guo has published over 140 peer-reviewed papers and book-chapters in the fields of earth and environmental sciences, with an H-index of 41 based on Google Scholar. He currently serves as an editorial board member of Scientific Reports, an open journal published by Nature Publishing Group, and the Journal of Riparian Ecology and Conservation, published by Versita Open.


PhD, Chemical Oceanography, Texas A&M University, 1995

Research Interests

  • Marine and freshwater biogeochemistry of carbon, nutrients and trace elements
  • Fate and transport of oil, dispersant and other chemical species
  • Aquatic colloids and nanoparticles
  • Applications of U-Th decay series and other radionuclides in aquatic environments
  • Biogeochemical processes at the land-ocean, river-lake, particle-water and biota-water interfaces
  • Biogeochemical consequences of climate and environmental changes
Recent and Selected Publications

Lin, H, and Guo, L. 2020. Variations in colloidal DOM composition with molecular weight within individual water samples as characterized by FlFFF and EEM-PARAFAC analysis. Environ. Sci. Technol.54, 1657-1667.

Li, D., Xie, L., Carvan, M.J. and Guo, L. 2019. Mitigative effects of natural and model dissolved organic matter on the toxicity of methylmercury in embryonic Zebrafish. Environmental Pollution252, 616-626.

Lei, X., Chen, M., Guo, L., Zhang, X., Jiang, Z.H. & Chen, Z.G. 2019. Diurnal variations in the content and oxygen isotope composition of phosphate pools in a subtropical agriculture soil. Geoderma 337, 863-870.

Xu, H., Lin, H., Jiang, H. and Guo, L. 2018. Dynamic molecular size transformation of aquatic colloidal organic matter as a function of pH and cations. Water Research144, 543-552.

Gao, L., Zhou, Z., Reyes, A. and Guo, L. 2018. Yields and characterization of dissolved organic matter from different-aged soil in northern Alaska. Journal of Geophysical Research-Biogeosciences123, 2035-2052.

Lin, P., Klump, J.V. and Guo, L. 2018. Chemical speciation and reactivity of phosphorus in suspended particles and sediments in seasonal hypoxia-influenced Green Bay, Lake Michigan. Journal of Great Lakes Research44, 864-874.

Baalousha, M., Afshinnia, K. and Guo, L. 2018. Natural organic matter composition determines the molecular nature of nanomaterial-NOM corona. Environmental Science: Nano5, 868-881.

Xu, H. and Guo, L. 2018. Intriguing changes in molecular size and composition of dissolved organic matter induced by microbial degradation and self-assembly. Water Research135, 187-194.

Yang, W. and Guo, L. 2018. Sources and burial fluxes of soot black carbon in sediments on the Mackenzie, Chukchi, and Bering Shelves. Continental Shelf Research, 155, 1-10.

Kteeba, S.M., El-Adawi, H.I., El-Rayis, O.A., El-Ghobashy, A.E., Schuld, J.L., Svoboda, K.R. and Guo, L. 2017. Zinc oxide nanoparticle toxicity in embryonic zebrafish: Mitigation with different natural organic matter. Environmental Pollution230, 1125-1140.

Xu, H. and Guo, L. 2017. Molecular size-dependent abundance and chemical composition of dissolved organic matter in river, lake and sea waters. Water Research, 117, 115-126.

Lin, P and Guo, L. 2016. Do invasive quagga mussels alter CO2 dynamics in the Laurentian Great Lakes. Scientific Reports6, 39078.

More publications can be found here.

Biogeochemistry, carbon cycle, colloids and nanparticles, stable isotopes, radionuclides, environmental change