HR: 09:45h
AN: NB31A-06    [Abstracts]
TI: Comparisons of Aquatic Invertebrate Assemblages in Small, Old Growth and Second Growth Forested Catchments of the H.J. Andrews Experimental Forest, Oregon
AU: * Frady, C H
EM: charles.frady@oregonstate.edu
AF: Department of Fisheries and Wildlife, 104 Nash Hall Oregon State University, Corvallis, OR 97331 United States
AU: Johnson, S L
EM: sherri.l.johnson@oregonstate.edu
AF: USFS PNW Research Station, 3200 Jefferson Way, Corvallis, OR 97331 United States
AU: Li, J L
EM: judith.li@oregonstate.edu
AF: Department of Fisheries and Wildlife, 104 Nash Hall Oregon State University, Corvallis, OR 97331 United States
AB: In small streams, riparian vegetation often composes the food base for many aquatic invertebrates. Forest harvest can result in major changes to riparian vegetation. If abundance, richness, or community structure of invertebrate assemblages is affected by removal of riparian vegetation, are legacies of these practices evident 20-40 years post-harvest? If so, are these differences uniform through time, or are they temporally dependant? We investigated stream invertebrate assemblage dynamics between old growth and second growth forest types and across seasons in six small-basins in the H.J. Andrews Experimental Forest. Individual basins range from 500m to 1000m in elevation and 12.4ha to 98.1ha in area. Six benthic samples and four, 1-week emergence samples were collected in each basin each season (June 2003 through May 2004). Preliminary results from benthic samples suggest strong changes in community structure between seasons as additional taxa not found in summer (i.e. Agathon, Anagapetus, Chernokrilus, and Rhyacophila "angelita group") were collected in autumn and winter samples. However, results from summer comparisons demonstrate no differences in benthic and emergence abundance (p = 0.47, and p = 0.98, respectively) or benthic richness (p = 0.41) between old growth and second growth invertebrate assemblages.
DE: 9902 NABS Student Award Applied Research
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly