HR: 14:45h
AN: U23B-06    [Abstracts]
TI: Development of an Advanced Respirometer for Experimental Studies of Benthic Rate Processes
AU: * Barry, J P
EM: barry@mbari.org
AF: Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, CA 95039 United States
AU: Buck, K R
EM: buku@mbari.org
AF: Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, CA 95039 United States
AU: Okuda, C
EM: craig@mbari.org
AF: Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, CA 95039 United States
AU: Risi, M
EM: mrisi@mbari.org
AF: Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, CA 95039 United States
AU: Parker, M
EM: pami@mbari.org
AF: Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, CA 95039 United States
AU: Levesque, C
AF: Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, CA 95039 United States
AB: Rates of carbon remineralization and nutrient cycling by seafloor biotic assemblages are influenced by the availability of organic material, temperature, and oxygen availability, among other factors. The relative importance of various factors in controlling carbon cycling by the sediment community is poorly constrained, in part by technological limits on experiments that evaluate independently the effects of these factors. We have developed an advanced respiration chamber system capable of repeated rate measurements during a single deployment, with added capabilities for manipulating conditions within replicate chambers to test hypotheses concerning biogeochemical cycling by the benthos. The ROV-deployed respiration system has 12 syringes for tracer injection or sample withdrawal from 3 respiration chambers, pH, oxygen, and temperature sensors, stirring paddles, and a recirculation pump. The pump system is used to flush each chamber at preprogrammed intervals or oxygen tensions. Areas of investigation that are enabled by the system include the effects various factors on benthic oxygen consumptions (e.g. hypercapnia (elevated CO2), acidosis, ambient oxygen availability, temperature, organic carbon availability), rates of nutrient regeneration by the benthos in response to organic enrichments (labile and refractory organic carbon), time lags in carbon uptake and trophic pathways in responses to organic enrichment.
DE: 4804 Benthic processes/benthos
DE: 4805 Biogeochemical cycles (1615)
DE: 4806 Carbon cycling
DE: 4845 Nutrients and nutrient cycling
DE: 4894 Instruments and techniques
SC: Union [U]
MN: 2005 Joint Assembly