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Dissolved-oxygen and algal conditions in selected locations of the Willamette River basin, Oregon

Open-File Report 81-529

By:
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Abstract

During July and August 1978, the U.S. Geological Survey, in cooperation with the Oregon Department of Enviromental Quality, made three intensive river-quality dissolved-oxygen studies in the upper Willamette River basin. Two studies were made on the upper Willamette River and one was made on the Santiam River, a Willamette River tributary. Nitrification, occurring in both the upper Willamette and South Santiam Rivers, accounted for about 62% and 92% of the DO sag in the rivers, respectively. Rates of nitrification were found to be dependent on ammonia concentrations in the rivers. Periphyton and phytoplankton algal samples were collected on the main stem Willamette River and selected tributaries during August 1978. Diatoms were the dominant group in both the periphyton and phytoplankton samples. The most common diatom genera were Melosira, Stephanodiscus, Cymbella, Achnanthes, and Nitzschia. Comparisons with historical data indicate no significant difference from previous years in the total abundance or diversity of the algae. (USGS)

Additional Publication Details

Publication type:
Report
Publication Subtype:
USGS Numbered Series
Title:
Dissolved-oxygen and algal conditions in selected locations of the Willamette River basin, Oregon
Series title:
Open-File Report
Series number:
81-529
Edition:
-
Year Published:
1981
Language:
ENGLISH
Publisher:
U.S. Geological Survey,
Description:
84 p. :ill., maps ;27 cm.