The purpose of this study was to develop a mass-balance model for total suspended solids in the Tualatin River in order to better understand the clarity-turbidity problem in the river. Major sources and sinks of suspended solids in the river were identified, and seasonal effects were explored. The study also...
Water quality and stream flow data for tliree representative land uses in the Tualatin River Basin were evaluated to determine the comparative levels of various pollutants. In addition, the data were used in an effort to identify the extent to which observed concentrations of total and ortho phosphorus could be...
Thesis summarizes interviews with growers residing within the Groundwater Management Area (GWMA) in the Southern Willamette Valley of Oregon. Informal and semi-structured interviews were used to identify perceived impediments and incentives perceived by local farmers in following best management practices related to water quality. Results from the interviews were coded...
About one-third of the land in the Tualatin Basin is used for agricultural production (Miner, Scott, and Wood, 1994). The variety of crops produced includes grains, specialty seeds, vegetables, fruits, berries, and nursery corps. Cattle and hog enterprises are the most prevalent livestock operations in the area (measured by number...
This report reviews and summarizes available information on aquatic biological communities in the Willamette Basin through 1995. Specifically, the report describes (1) the distribution, abndance, and trends of three taxonomic groups--algae, macroinvertebrates, and fish--and, to a lesser degree, other selected semi-aquatic taxa (i.e., taxa frequenting but not living wholly in...
Open field burning is the lowest-cost method of harvest residue
disposal used extensively by grass seed producers in the Willamette
Valley of Oregon. The beneficial effects of open field burning include
effective disease control and increased seed yields. However, smoke
produced by open burning in the late summer pollutes valley...
The purpose of this research is to investigate how stakeholders involved in collaborative watershed groups in Oregon work with each other to form ideas and take action. Most collaboration efforts include encouraging a high level of trust with a great value placed on relationships and partners, being open and flexible,...
Fresh-water benthic river algae were collected from selected
sites in Willamette River tributaries; two sampling sites were in the
Yamhill River system and four sampling sites were in the Santiam
River system. Twelve samples were taken at each collection site in
the Yamhill River system at approximately monthly intervals from...