Fate of Nitrite Determines Nitrogen Removal in Coastal Waters

2019 Faculty Research Award

Award Period: 2019-2021

Bess Ward, the William J. Sinclair Professor of Geosciences and the Princeton Environmental Institute, will work in the Chesapeake Bay examining the microbial reactions that control levels of nitrogen in coastal waters. Coastal waters are experiencing an excess of fixed nitrogen due to runoff and atmospheric deposition. Bacteria convert this fixed nitrogen into the inert gases, which reduces eutrophication in which excess minerals spark the explosive growth of phytoplankton that deplete oxygen levels for marine plants and animals.

Nitrite is a critical pivot point in this process that determines whether fixed nitrogen is lost from the system or recycled back to nitrate, which is an important nitrogen source for phytoplankton. Ward and her research group will determine the distribution and regulation of microbial reactions that consume nitrite and remove nitrogen, particularly in oxygen-free (or anaerobic) conditions. The project is among the first to study this process in coastal waters and as it occurs in different seasons and water depths. The findings could provide a better understanding of how the natural regulation of nitrogen could be altered as climate change increases the presence of nutrients in bodies of water.


Educational Impact

The project will provide laboratory and fieldwork experience for undergraduates working on the project as PEI summer interns and on independent research for their senior thesis. Students will work directly with Ward as well as with graduate students and postdoctoral researchers during research cruises to collect samples from Chesapeake Bay and in the lab.

Participating Department


William J. Sinclair Professor of Geosciences and the Princeton Environmental Institute

Research Associates

  • Amal Jayakumar, Senior Professional Specialist, Geosciences

Graduate Students

  • Xin Sun, GEO
  • Naomi Intrator, GEO

Undergraduate Students 

  • Levy Nathan ‘21