PRINCIPAL 

 INVESTIGATOR(S) 



Sharon L. Smith 



Rosenstiel School of Marine and Atmospheric Science 



Division of Marine Biology and Fisheries 



4600 Rickenbacker Causeway 



Miami, Florida 33149 



PROJECT TITLE 



THE ROLES OF ADVECTION AND IN SITU GROWTH IN 

 DETERMINING THE DYNAMICS OF CONTINENTAL 

 SHELF ZOOPLANKTON: HIGH FREQUENCY 

 MEASUREMENTS OF ZOOPLANKTON BIOMASS 

 COUPLED WITH MEASUREMENTS OF SECONDARY 

 PRODUCTIVITY IN THE MIDDLE ATLANTIC BIGHT 



AMOUNT OF FUNDING FY 1994: $81 K 



SUMMARY OF GOALS 



In trying to quantify the extent to which physical and biological forcing are responsible 

 for observed distributions of zooplankton, in a way that helps us understand and predict how 

 systems work, we need to be able to extrapolate biological forcing (variables associated with 

 population growth), usually observed on small to mesoscales, to larger scales. And we need 

 to know in general whether physical forcing has a positive or negative feedback to the biological 

 system. Any extrapolation is dependent on larger scale observations, such as an assessment of 

 biomass by the acoustic Doppler current profiler, which have been impossible to make until 

 recently. We will build on our knowledge from our earlier studies and investigate the "biomass 

 field", using the acoustic Doppler current profiler, and the processes that can be deduced from 

 combining the biomass field with measurements of growth (egg production), with measurements 

 of grazing rates, and with formalized, algorithm-like treatments of other processes such as 

 respiration. 



To establish quantitatively the role of larger zooplankton in the cycling of carbon on the 

 continental shelf of the northeastern United States by measuring biomass using five acoustic 

 Doppler current profilers deployed as a box, by measuring biomass using towed MOCNESS 

 nets, and by measuring growth and grazing rates using ship-board incubation experiments. To 

 separate and understand the roles of advection and in situ growth in determining the biomass 

 patterns observed and their impact on the carbon cycle. 



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