Thanks to the many who replied on the back channel to my puzzlement over a disagreement I had with a student in my fish biology class.
The ruling is virtually unanimous: I'm all wet. Flow velocity is not solely, or even predominantly, a function of gradient. Well-established formulae (especially Manning's formula) express velocity as a function of gradient, hydraulic radius (dependent on channel depth and width) and bottom roughness. While low order streams have high gradient the other two terms tend to retard flows.
I especially appreciated the gentility of the responses. What seemed puzzling yesterday is now just about intuitive, yet the respondents did not write as if this were a trivial matter and I a loutish dolt. Thanks to the netter who pointed out my careless mis-statement about the quantification of discharge.
I would be happy to send the responses I got to any who request it.
I have saved / /// _* )=>=======<< ) ` \\ Eric Schultz
web page: HTTP://WWW.EEB.UCONN.EDU
fish class home page: http://yoda.ucc.uconn.edu/users/schultze/BIO200.htm
Department of Ecology and Evolutionary Biology 75 N. Eagleville Rd. University of Connecticut Storrs CT 06269-3042 Phone (860) 486-4692 Fax (860) 486-4320
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