METHODS AND PLATFORMS 



Studies will be based primarily on sediment samples obtained by cores and by in situ 

 benthic flux chamber incubations. Sediment and pore water analyses will be performed on the 

 core samples to assess reaction rates and processes. 



STRENGTHS AND LIMITATIONS OF PROPOSED RESEARCH 



Sea floor studies take advantage of the physical framework provided by the bottom 

 sediments to identify organic matter transformation processes and quantify reaction and sea floor 

 exchange rates. Because bottom sediments provide a fixed framework in which to interpret 

 concentration measurements and benthic chamber incubations, reaction rates and exchange rates 

 can be more accurately assessed than in settings where such a framework does not exit. 



Pore water and benthic exchange studies are limited by sampling techniques. Presently, 

 there are no pore water measurements that may be performed in a remote, continuous manner, 

 analogous to the continuous, mooring-based measurements in the water column. Pore water 

 measurements are presently limited to shipboard procedures and may be obtained at a rate of 3-5 

 profiles per day. In situ benthic flux chamber measurements are limited by incubation length, 

 estimated to be .5 day at shelf locations and 2 days on the slope. 



STATUS OF RESEARCH 



Slope pore water measurements and in situ benthic flux incubations have been performed 

 in an attempt to estimate and determine the location of off-shelf export. Plans for this summer 

 expedition include continued slope and rise measurements and preliminary shelf sampling. 



Keywords: carbon deposition, benthic fluxes, nutrient fluxes, benthic cores 



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