Model-Driven Investigations of Ocean Transition Zones

  • Awardees
  • E. Virginia Armbrust, Ph.D. University of Washington
  • Randelle Bundy, Ph.D. University of Washington
  • Zoe Finkel, Ph.D. Mount Allison University
  • Michael J. Follows, Ph.D. Massachusetts Institute of Technology
  • Anitra Ingalls, Ph.D. University of Washington
  • Seth John, Ph.D. University of Southern California
  • Laurie Juranek, Ph.D. Oregon State University
  • David M. Karl, Ph.D. University of Hawaii
  • Debbie Lindell, Ph.D. Technion-Israel Institute of Technology
  • Angelicque White, Ph.D. Oregon State University
  • Jonathan P. Zehr, Ph.D. University of California, Santa Cruz
Year Awarded


About This Project Award:

The transition zones between the North Pacific Subtropical Gyre (NPSG) and neighboring ecosystems, notably the subpolar gyre, exhibit steep changes in environmental conditions (gradients) associated with dramatic changes in the microbial ecosystem. These zones provide suitable venues to understand mechanisms that structure microbial communities and to test ecological theory of how resource supply ratios drive productivity, export, particle size distributions, and elemental stoichiometry. A multidisciplinary team led by Ginger Armbrust is testing three interconnected hypotheses via interrogation of model simulations and direct observations of the transition zone between marine ecosystems.

The hypotheses are:

(1) Enhanced productivity occurs at the transition zone because resources, such as fixed nitrogen and iron, are supplied at close to the optimal ratio for phytoplankton productivity.

(2) Changes in the particle size distribution (PSD) across the front are predictable and related to the community of primary producers and those factors that influence their growth and mortality. The PSD is directly related to enhanced export of sinking particulate carbon at the transition zone and can be used to study non-steady state changes in community structure and productivity in the NPSG.

(3) Trends in elemental and macro-molecular composition of primary producers vary predictably across the transition zone according to principles of resource ratio competition models

Advancing Research in Basic Science and MathematicsSubscribe to Life Sciences announcements and other foundation updates