CARBON IN FRESHWATER SYSTEMS 261 



et al., 1972) is inadequately resolved, we believe the original NEP concept to be 

 a valuable tool in the ultimate elucidation of carbon and energy ecosystem 

 dynamics. 



ACKNOWLEDGMENTS 



The support of the U. S. Atomic Energy Commission throughout the study 

 is gratefully acknowledged. Of many persons involved in the investigations, we 

 particularly wish to thank M. C. Miller, H. L. Allen, J. Sonnad, M. Hewitt, and 

 those who more recently came into the picture: A. Otsuki, B. A. Manny, R. A. 

 Hough, and W. S. White. Dr. G. H. Lauff offered critical insight on the 

 manuscript. 



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