N-189. A Time Series of Continuously Coregistered Temperature, Chemistry and Microbiology at a Diffuse Flow Hydrothermal Vent at the Juan de Fuca Ridge

J. Robidart1, G. Wheat2, P. Girguis1;
1Harvard Univ., Cambridge, MA, 2Univ. of Alaska, Fairbanks, AK.

Osmosamplers use osmotic pressure to continuously sample sea water and can be deployed on the order of weeks to years. Upon recovery, the sample tubing contains a time series where the distance from the inlet is directly proportional to the time at which the seawater was sampled. We are currently adapting these chemical osmosamplers for microbial sampling by the addition of various reagents in order to collect and preserve proteins, nucleic acids, and cellular structure (for microscopy). Molecular degradation in a variety of preservatives was <50% (DNA) and <15% (proteins) at 6 months, allowing at least 6 months resolution of biogeochemical interactions. A 3-week pilot experiment consisting of independent samplers for ionic and volatile chemistry as well as protein and nucleic acid preservation was deployed at a diffuse flow vent site at the Juan de Fuca Ridge. A significant change in mean temperature was recorded which lasted 4 days. This temperature change correlated with a change in chemistry (including methane and analyzed via gas chromatography and ICP-MS) and in the microbial community based on clone library analyses. This proof-of-concept experiment allowed us to correlate changes in microbial population structure with changes in the physicochemical environment at a discrete location in the diffuse flow hydrothermal environment. The development of osmosamplers as microbiological sampling tools allows us for the first time to collect a high resolution co-registered suite of chemical and microbiological samples in the deep ocean, without the use of complex electro-mechanical sampling systems.