BENTHIC INFAUNA OF LYDONIA CANYON 

 AND THE ADJACENT SLOPE ENVIRONMENT 



Dr. Nancy J. Maciolek 



(formerly of) Battelle Ocean Sciences 



Duxbury, MA 



and 



Dr. J. Frederick Grassle 



Woods Hole Oceanographic Institution 



Woods Hole, MA 



The Georges Bank Benthic Infauna Monitoring Program was carried out 

 between 1981 and 1984, and a deep-water characterization study (Study of 

 Biological Processes on the U.S. North Atlantic Slope and Rise) was made from 

 1984 to 1986. In both programs, the benthos was sampled quantitatively at 

 several stations including stations in Lydonia Canyon and on the adjacent 

 slope. The canyon/slope stations were at three water depths: approximately 

 150, 550, and 2,100 m. Stations were sampled from 3 to 8 times. Sampling was 

 conducted seasonally, but because we did not see pronounced seasonal effects, 

 the results are presented as an overview for each station. 



COMMUNITY STRUCTURE 



To assess community structure of the infaunal benthos, we recorded 

 species composition and abundance, and then determined which species were 

 numerical dominants at a station on a given sampling date and over all 

 sampling dates. We also looked at diversity using the Shannon-Wiener 

 information index and the Hurlbert rarefaction method. Similarity among 

 samples and stations was also evaluated using the NESS similarity measure, 

 followed by cluster analysis. 



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