Field work is integral to our study of biogeochemical cycles, paleoclimate, and paleoaltimetry.  We engage in oceanographic and freshwater research on phosphorus cycling.  We are building a program to measure air quality parameters in and around urban environments.  In terrestrial settings, we have also investigated carbon monoxide cycling in anaerobic geothermal settings.  Many elements of our field work are complimented by laboratory experiments and microbial culturing. 

The links below provide a stronger glimpse into these field campaigns.  Student field work has extended far beyond the range listed below, including paleoelevation studies in Tibet, the microbial community and chemistry of active layer and permafrost soils in the Alaskan Tundra, phosphorus cycling in the North Atlantic Subtropical Gyre, and carbon isotope signal of mesoscale upwelling along the Pacific NW continental margin, and paleoseasonality studies in the Turkana Basin of Kenya.

Oceanic Flux Program Cruises, Sargasso Sea

April & October 2014, April 2016

Our primary focus in these OFP cruises was to investigate the controls on particulate phosphorus export from the oligotrophic surface ocean and P regeneration from suspended and sinking particles in the water column.  This in turn helps us to understand the nutrient controls on photosynthetic carbon sequestration.  We conducted a series of shipboard experiments on nutrient regeneration, and with Maureen Conte (MBL Ecosystems Center & BIOS, PI of OFP) we are studying  phosphorus dynamics in the sinking particle flux.

We conducted broad ranging investigations into the links between hot spring chemistry, microbial community composition, and carbon monoxide cycling by anaerobic bacteria and archaea.  This field program originated with a major collaborative effort through the Kamchatka Microbial Observatory and continued with a more targeted follow-up study with collaborator Frank Robb (U. Maryland).

The Lassen field program extended our Kamchatka investigations, which were centered on circum-neutral pH springs, to the much more acidic springs in Lassen.  We teamed up with the LVNP Microbial Observatory to complete this work.

GEOTRACES is a major international oceanographic campaign designed to map and model the distribution of trace elements and their isotopes in the ocean.  These tracer distributions are revealing major aspects of the physical, chemical, and biological pathways for element cycling in the oceans. We led the intercalibration efforts for measuring the oxygen isotope composition of dissolved phosphate (δ¹⁸Op), which provides an integrated signal of P biogeochemical cycling.  We also measured sea water δ¹⁸O, which serves as a conservative tracer of deep ocean circulation.