Distribution and Magnitude of Dinitrogen Fixation in the Eastern Tropical North Pacific Deficient Zone
College of Sciences
As a fundamental component of life’s building blocks, proteins and nucleic acids, nitrogen plays a vital role in shaping Earth’s biosphere. When biologically-accessible forms of nitrogen like nitrates become scarce, organisms cannot grow and reproduce. Indeed, humankind’s population growth would have already reached its maximum if it were not for industrial production of such compounds from N2 gas, which makes up 78% of the atmosphere but cannot be used as a nitrogen-source by most organisms because the bond linking the two N atoms is too strong for them to break. While human innovation enabled industrial production of biologically-accessible nitrogen, this process—known as N2 fixation—has been carried out on Earth for billions of years by microbes. Inputs of new biologically-accessible nitrogen via N2 fixation is counterbalanced by denitrification, the microbially-mediated transformation of bioavailable nitrogen to N2. How these processes balance through time and space is essential to understanding Earth’s history and, because nitrogen availability limits the ability of phytoplankton in the ocean to sequester atmospheric carbon, Earth’s future as well. Here, we present recent work exploring the spatial coupling between N2 fixation and denitrification in the ocean.
Selden, Corday, "Distribution and Magnitude of Dinitrogen Fixation in the Eastern Tropical North Pacific Deficient Zone" (2019). College of Sciences Posters. 24.