Aquatic Sciences Meeting, Albuquerque 2001

CS01 Air-Water Interactions

Date: Wednesday, February 14, 2001, Time: 2:30:00 PM

Location: San Miguel

Shaw, S, L, Department of Earth, Atmospheric, and Planetary Sciences, MIT, Cambridge, MA, USA, slshaw@mit.edu

Chisholm, S, W, Departments of Civil and Environmental Engineering and Biology MIT, Cambridge, MA, USA, chisholm@mit.edu

Prinn, R, G, Department of Earth, Atmospheric, and Planetary Sciences, MIT 54-1323, Cambridge, MA, USA, rprinn@mit.edu

NON-METHANE HYDROCARBON PRODUCTION BY CYANOBACTERIA AND PHYTOPLANKTON

There has been recent interest in the marine water column as a source of non-methane hydrocarbons (NMHC) to the remote atmosphere. Substantial uncertainty exists in the relative contributions of photosynthetic/other organisms and aquatic photochemistry to this process. We measured NMHC production rates on the order of 1 - 10 nanomoles/gram dry weight/day from several phytoplankton monocultures. Per biomass, the cyanobacteria Prochlorococcus marinus and Synechococcus sp. have similar isoprene, ethane, and ethene production rates to the eukaryote Emiliania huxleyi. Isoprene is produced proportionally to cell counts, and requires light. Axenic and heterotrophic-bacteria containing cultures were compared and found to have similar isoprene production rates. Grazing by the nanoflagellate Cafeteria Roenbergensis only affects NMHC through phytoplankton counts; viral lysis effects on NMHC production were also examined. Species-specific estimates of isoprene production in the oligotrophic ocean were calculated from standing stock biomass estimates and are on the order of 10 nanomoles isoprene/m2/day. As expected, isoprene production from phytoplankton is small compared to that of higher plants, but may still be sufficient to affect remote boundary layer chemistry.

Return to This Session's Schedule · Complete Session Listing ·

Aquatic Sciences Meeting, Albuquerque 2001

Quicklinks