PRINCIPAL 

 INVESTIGATOR(S) 



Both at: 



Brian Fry and Charles Hopkinson 



The Ecosystems Center 

 Marine Biological Laboratory 

 Woods Hole, MA 02543 



Mark Altabet 



Woods Hole Oceanographic Institution 



Woods Hole, MA 02543 



PROJECT TITLE 



ORIGINS AND FATES OF DISSOLVED ORGANIC MATTER 

 ALONG THE NEW ENGLAND CONTINENTAL MARGIN 



AMOUNT OF FUNDING FY 1994: $289 K 



SUMMARY OF GOALS 



1. We are characterizing the cycling of dissolved organic matter along the eastern U.S. coast, 

 using samples collected on three offshore cruises. We are using a combination of concentration 

 and isotopic measurements (DOC, DON, D0 13 C, D0 14 C, D0 15 N, POC, PN, P0 13 C, P 15 N,), as well 

 as ancillary measurements of inorganic nutrients to develop our understanding of the offshore 

 DOM cycle. 



2. We are also performing mesocosm experiments (4 to 1000 1) that test controls of DOM 

 formation and degradation. Of particular interest is the preferential storage and release of C and 

 N species during DOM cycling. These experiments require time course measures of TC0 2 in 

 addition to those mentioned above. 



3. There is also considerable emphasis (50% of effort) in developing new techniques for 

 measuring isotopic contents of DOM, i.e., D0 13 C, D0 14 C and D0 15 N. We are trying to finish 

 this work in our final year of current funding, which ends lune 1, 1995. 



SPATIAL AND TEMPORAL SAMPLING SCALES 



We have participated in an April 1993 cruise to Georges Bank and an April 1994 cruise 

 from Georges Bank to Cape Hatteras. We are hoping for a short 3-day cruise to Georges Bank 

 this summer (luly 1994). 



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