benthic sampling

[Fraser R. Sime]

I am in the process of trying to come up with a quantitative if possible,
qualitative if necessary method for sampling a difficult stream system for
aquatic macroinvertebrates.  This system is slow moving and has been
impacted by sedimentation over time.  There are large areas where
macrophytes such as Elodea sp. have taken over much of the channel width.
One of our goals is to assess the impacts of this plant growth to the
benthic community.  It would be nice to be able to statistically compare
relatively plant-free areas to the more impacted sites.  We need to come up
with a method for sampling those areas which are unwadable and heavily
infested with plant growth.

Does anyone have any ideas on statistically valid sampling methodologies
for assessing benthic communities in such a system?

Please respond to me off list - if there is any great interest, I will post
the results.
Thanks for the help!
Fraser

Fraser R. Sime
Environmental Specialist
California Department of Water Resources
2440 Main St.
Red Bluff,  CA   96080
(916) 529-7374
FAX (916) 529-7322