METHODS AND PLATFORMS 



The TS-SID's operate completely autonomously and possess a mooring-strength frame, 

 permitting the instruments to be incorporated directly into the mooring line in series with other 

 instrumentation (cage dimensions housing instrument components, 27" x 27" x 41", not including 

 apex to attachment points at either end; total length from attachment point to attachment point, 

 82"). During ship-based cruises one or more of the TS-SID's may be deployed on free-drifting 

 surface moorings. The moorings are tracked by radar, radio beacon and light flasher, and would 

 require a cruise where the ship predominately stays within a region. Because of risk of 

 instrument loss, deployments would not be compatible with survey cruises where time at a given 

 station is short and the ship travels large distances. Ship laboratory space would be necessary 

 for recycling of the instruments and C-14 sample processing. 



STRENGTHS AND LIMITATIONS OF PROPOSED RESEARCH 



Strengths: 1) Autonomous performance of in situ tracer incubation experiments, physiological 

 studies possible. 2) A single instrument can be used for a wide variety of studies, depending 

 upon tracers implemented. 3) Temporal resolution of incubations (e.g., primary production) 

 usefully on par with high temporal resolution physical and bio-optical time series measurements. 

 4) The instruments may be deployed for relatively long periods. Biofouling control measures 

 have been incorporated into the instrument so that the internal and external surfaces of the 

 incubation chamber may be acid cleaned and kept free of light-occluding material. 5) The 

 instruments are modular, size can be modified as a function of the number of incubations to be 

 performed per deployment. For example, a version of the instrument to be deployed during 

 cruises would be smaller than the moored instrument as biofouling control would not be required 

 and approximately one-half the number of subsamples would be necessary. The instrument 

 would be retrieved at appropriate intervals and recycled to preserve high temporal resolution. 



Limitations: 1) Spatial and depth-dependent resolution a function of the number of instruments 

 available. 2) A finite number of subsamples can be taken (93 pairs), hence, temporal resolution 

 and deployment longevity are inverse functions of one another, and both variables are decreased 

 if the number of subsamples per incubation are increased (i.e., time course incubations). 



STATUS OF RESEARCH 



We have built a Time Series - Submersible Incubation Device (TS-SID), a 

 mooring-compatible, automated instrument for performing multiple in situ microbial incubation 

 experiments. Each incubation involves a cleaning cycle, procurement of a 400 ml sample at 

 depth with simultaneous introduction of tracer, and the preservation of up to four pairs of 

 subsamples during incubations of user-determined length. The device is capable of conducting 

 47 in situ end point incubations (tO, tl; i.e., zero time, time 1) or 31 three-point time course 

 incubations (tO, tl, t2) at user determined intervals. During each deployment a total of 93 



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