Research Assistant Professor
Ph.D., Rostock University, Germany, 2004
Biogeochemical cycling of organic matter in aquatic environments; carbon flux in and around sinking particles (marine snow); sedimented marine snow and benthic-pelagic coupling; oil-carbon dynamics and the microbial oil degradation cascade; deep-sea, coastal ocean and estuaries, shallow lakes.
My research integrates the fields of geochemistry and microbiology to investigate biogeochemical cycling of organic matter (OM) in the ocean. I am studying the role of heterotrophic microorganisms in OM degradation on scales ranging from ocean basins to microenvironments such as marine snow aggregates. Marine snow forms in surface waters at the decline of a phytoplankton bloom, consisting of a wide variety of organic substrates and inorganic matter. Sinking aggregates are responsible for the downward flux of most of the photosynthetically fixed carbon, fueling deep ocean food web interactions. Despite the important role in the ocean's biological pump, there are still numerous open questions on the role of marine aggregates in the marine carbon cycle. My research on this topic aims to answer the following questions:
- How do OM degradation rates in sinking aggregates change from their formation in the surface ocean to their deposition on the deep seafloor?
- How do physical processes in the water column, such as stratification and turbulent mixing, affect marine snow-associated biogeochemical processes?
- What are the effects of marine snow formation on the fate of hydrocarbons in the ocean?
To answer these questions I conduct seagoing research with the focus on the northern Gulf of Mexico and the Mid-Atlantic Bight, and culture-based laboratory experiments with experimental set-ups that facilitate marine snow formation under controlled conditions.
Another aspect of my research deals with organic matter and nutrient cycling in shallow waters such as estuaries and shallow lakes. Marine snow as well as lake snow can be abundant at times in these environments, representing an important link between benthic and pelagic microbial food webs.
Passow U. and K. Ziervogel (2016) Marine snow sedimented oil released during the Deepwater Horizon oil spill. Oceanography: 10.5670/oceanog.2016.76
Ziervogel K., Dike C., Asper V., Montoya J., Battles J., D'souza N., Passow U., Diercks A., Esch M., Joye S., Dewald C., Arnosti C. (2015) Enhanced particle fluxes and heterotrophic bacterial activities in Gulf of Mexico bottom waters following storm-induced sediment resuspension. Deep-Sea Research II: 10.1016/j.dsr2.2015.06.017i
Prairie J. C., Ziervogel K., Camassa R., McLaughlin R.M., White B.L., Arnosti C. (2015) Delayed settling of marine snow: Effects of density gradient and particle properties and implication for carbon cycle. Marine Chemistry 175: 28-38.
Arnosti C., Ziervogel K., Yang T., Teske A. (2014) Oil-derived marine aggregates – hot spots of polysaccharide degradation by specialized bacterial communities. Deep-Sea Research II: 10.1016/j.dsr2.2014.12.008
Ziervogel K., D’souza, N., Sweet, J., Yan, B., Passow, U. (2014) Natural oil slicks fuel surface water microbial activities in the Gulf of Mexico. Frontiers in Aquatic Microbiology 5: 10.3389/fmicb.2014.00188
Ziervogel K., Leech D., Arnosti C. (2013) Extracellular enzymes in shallow lakes of differing trophic status. Biogeochemistry: 10.1007/s10533-013-9874-9
Ziervogel K., McKay L., RhodesB., Osburn C.L., Dickson-BrownJ., ArnostiC., Teske A.(2012) Microbial activities and dissolved organic matter dynamics in oil-contaminated surface seawater from the Deepwater Horizon oil spill site. PLoS One 7(4): e34816: 10.1371/journal.pone.0034816