Representative sites of the Dayton, Woodburn, Jory, Quillayute, Astoria, Willamette, Walla Walla, Deschutes, Laki and Owyhee soil series were investigated for seasonal changes in exchangeable potassium in air dry samples. No consistent seasonal variations were found which could be attributed to wetting and drying in the field. Cropping reduced the...
Two soils representative of the coast and three representing the Willamette Valley have been studied for their general chemical
characteristics. Exchange capacity and exchangeable cations were
determined by the ammonium acetate and the BaCl₂-triethanolamine
buffer methods. Exchange capacity was also obtained from conductimetric
titrations which were run on each soil...
This study provides an empirical test of the Bockstael-McConnell
(1980) household production function (HPF) framework for evaluating wildlife recreation. This is perhaps the first study in which
both taste and technology parameters have been estimated with a
theoretical model specification. The results suggest that for
steelhead sport fishing in Oregon,...
Despite evidence that juvenile Chinook salmon (Oncorhynchus tshawytscha) utilize North Pacific estuaries for growth and salinity acclimation, research in the Columbia River estuary has lead to opposing hypotheses about the estuary’s importance as a salmon rearing environment. Many contemporary tagging studies indicate that salmon residency within the estuary is short...
The myxozoan parasite, Ceratomyxa shasta, is the most significant pathogen of juvenile Chinook salmon (Oncorhynchus tshawytscha) in the Klamath River, CA, USA. This parasite requires two hosts - a freshwater polychaete (Manayunkia speciosa) and a salmonid - to complete its life cycle. The complex life cycle and large geographic area...
Tidal wetland channels provide rearing habitat for juvenile Chinook salmon as they emigrate from freshwater habitat and prepare to enter the ocean. Widespread diking and drainage of estuarine marshes for agricultural and urban development may have contributed to a decline in salmon abundance in the Pacific Northwest, prompting efforts to...