Abstract:
The effects of forest cutting on forested systems and the biotic components of
those systems has been at the forefront of scientific research. The inventory and
monitoring of biodiversity is one technique used for measuring the effects of forest
management. Because bioinventory studies are expensive, indicator species are
often sought to serve as surrogates for the entire biotic community. Insects may be
useful as indicator species. The purpose of this study was to perform an inventory of
the ground dwelling beetles of the H.J. Andrews Experimental Forest, and then use
that inventory to assess the impact of forest management. Beetle communities were
compared over time (17 years) and across variously aged stands and associated floral
communities to determine the effects of clear-cut management. Pitfall traps were
used at 37 sites to collect ground dwelling Coleoptera over a three week period in
1982, 1983, and 1999. A total of 11,191 individuals of 224 species were collected.
The resultant catch was analyzed using univariate and multivariate statistical
techniques. Results showed significantly different beetle communities among the
four seral stages sampled. Beetles were more abundant in old growth sites. Species
diversity was highest in clear-cut sites. Vegetation association was shown to
significantly affect beetle communities, but was dependent on level of definition.
Time also significantly affected beetle communities, with the beetle assemblages
following a predictable trajectory parallel to vegetation succession. Functional group
composition was found to change significantly over time, but was inconsistent
between years.
