subsample pairs (186 total) are preserved for subsequent analysis. If background (tO) activities 

 are sufficiently low, it is possible to make tO measurements at less frequent intervals, thereby 

 increasing the total number of possible incubations. For example, if tO measurements were made 

 every 5th incubation the total number of possible incubations increases to 75 (tO activities 

 interpolated between each 5th incubation where the measurement is made). Initial emphasis has 

 been placed upon C-14 measurements of phytoplankton primary production, but the device is 

 applicable to any tracer study requiring incubation. 



In the interdisciplinary field studies, we would perform the following measurements. 



1) Deployment of TS-SID's (at least 3 units, hopefully) for moored high temporal 

 resolution time series measurement of C-14 primary production. Instrument location will be 

 coordinated with the along-shelf and across-shelf OMP mooring program so that the TS-SID data 

 can be integrated with ongoing time series measurements of water column physical properties, 

 nutrient dynamics and bio-optical properties, in particular fast repetition rate (FRR) fluorometry. 

 During part or all of the deployment period the TS-SID's will be configured to measure C-14 

 primary production in multiple short term incubations (up to 4 incubations per day, 2-3 hr per 

 incubation) to provide a measure closely approximating gross photosynthesis throughout the light 

 period. 



2) Implementation of the TS-SID's in a longer term incubation mode where measures 

 of the intracellular distribution of C14 tracer will be implemented for estimating phytoplankton 

 respiration in the light and dark, and for providing more accurate estimates of excreted organic 

 carbon (EOC). The overall approach will take advantage of the instrument's ability to obtain 

 time course subsamples during each incubation in a manner that will allow subsequent subcellular 

 fractionation of samples for quantifying the dynamics of the flow of tracer into each of the major 

 classes of biopolymers, low molecular weight metabolites and excretion products. This 

 information will relate to the overall physiological state of the population (e.g., dynamic growth 

 vs. senescence), and under the correct conditions can provide information on respiratory carbon 

 loss and excretion. 



Keywords: primary production, submersible remote incubator 



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