The Environmental Monitoring and Assessment Program (EMAP) site selection
protocol was used to generate a random sample of streams throughout the state of
Oregon. One hundred and forty-six selected streams were sampled during the summer,
low-flow period of 1997. Traditional microbial public health indicators, including
heterotrophic plate counts (HPC), total coliforms (TC), fecal coliforms (FC) and E. coli,
were enumerated using the membrane filtration technique. Nearly 17% (3.4-23.6%,
95% C.I.) of streams exceeded the current state of Oregon standard for water-contact
recreation. Levels of bacteria were also shown to differ significantly by ecoregion. The
Cascades ecoregion had low levels of all types of bacteria. The Willamette Valley,
Columbia Plateau and Snake River Basin had high levels of one or more groups of
bacteria measured. Twenty-six sites were resampled and FC and E. coli estimates were
not significantly different for the different sampling dates.
Biolog GN plates were used to provide a measure of the functional diversity of
microbial communities for the same streams as above. Two groups were formed based
on inoculum density and Biolog GN plates were analyzed using principal component
analysis (PCA). The first few principal components explained nearly half of the variation of the data in both groups. Principal components were correlated with the average carbon source utilization, levels of coliform bacteria, and ecoregions. These results indicate that patterns produced by Biolog GN plates may be useful in the assessment of ecological condition of freshwater streams. Subsequent publications will explore the relationships between the pattern of substrate utilization of Biolog GN plates with other indicators of ecological function. / Graduation date: 1999
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/33590 |
| Date | 29 September 1998 |
| Creators | Campbell, Heidi M. K. |
| Contributors | Harding, Anna K. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
Page generated in 0.0018 seconds