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651. [Image] The Chemical and biological impact of Klamath Marsh on the Williamson River, Oregon


	A comparative study of the Williamson River (before and after passage through Klamath Marsh) and the Sprague River (which is a major tributary of the Williamson River) in South Central Oregon has provided ...
	Citation Citation Citation Abstract Copy Title: The Chemical and biological impact of Klamath Marsh on the Williamson River, Oregon Author: Perdue, Edward M. Year: 1981, 2005 A comparative study of the Williamson River (before and after passage through Klamath Marsh) and the Sprague River (which is a major tributary of the Williamson River) in South Central Oregon has provided substantial insight into the effects of a marsh environment on the transport of iron and aquatic humus in river water. In the Sprague River and in the pre-marsh Williamson River, iron is transported primarily as 0.80 ym suspended particulate material. In Klamath Marsh, this coarse particulate material is "weathered11, yielding iron-aquatic humus "complexes'1. Thus, most iron and aquatic humus in the post-marsh Williamson River are in the 0.025 ?m size fraction. Presumably, other trace metals would be similarly affected. Klamath Marsh serves as an important source of biologically derived solutes such as amino acids and sugars. Fractionation studies have shown that amino acids are almost exclusively humic-bound in the Will-iamson River system, while sugars may be present as either polysacchar-ides (PS) or humic-bound saccharides (HS). The PS/HS ratio may reflect the relative importance of autochthonous and allochthonous sources of sugars. Major solute composition strongly indicates that ground waters flowing into the pre-marsh Williamson River and the Sprague River are derived from a different source than are ground waters which enter the post-marsh Williamson River from Big Springs, Spring Creek, and from unidentified springs below Klamath Marsh. Nutrient concentrations (H4SiO4, NO3, PO43) are significantly higher in spring waters than elsewhere in the system. While nitrate levels (3-11 ?m) were somewhat low, phosphate levels (1-3 ?m) were quite high throughout the Williamson River system. There was some evidence for nitrogen limitation of algal growth in the pre-marsh Williamson River. While Fragilaria construens was dominant throughout the Williamson River system, several Navicula spp. were restricted to the pre-marsh Williamson River and several Fragilaria spp. and Nitzschia, spp. were found only in the post-marsh Williamson River. In Upper Klamath Lake, Stephanodiscus astrea minuta, Fragilaria construens, and Aphanizomenon flos-aquae appeared in succession, with nuisance blooms of the latter organism occurring July-November. The cessation of flow of humic-rich water from Klamath Marsh during the summer months drastically decreased the flux of aquatic humus, iron, amino acids, and other marsh-derived solutes in the post-marsh Williamson River. At the time of cessation of flow from Klamath Marsh, nuisance blooms of Aphanizomenon flos-aquae appeared in Upper Klamath Lake. Furthermore, when flow from the marsh was re-established with the first major winter rains in November or December, Aphanizomenon flos-aquae abruptly ceased to grow in Upper Klamath Lake. Further studies are planned to determine whether this correlation is causal or coincidental. Title: The Chemical and biological impact of Klamath Marsh on the Williamson River, Oregon Author: Perdue, Edward M. Year: 1981, 2005 A comparative study of the Williamson River (before and after passage through Klamath Marsh) and the Sprague River (which is a major tributary of the Williamson River) in South Central Oregon has provided substantial insight into the effects of a marsh environment on the transport of iron and aquatic humus in river water. In the Sprague River and in the pre-marsh Williamson River, iron is transported primarily as 0.80 ym suspended particulate material. In Klamath Marsh, this coarse particulate material is "weathered11, yielding iron-aquatic humus "complexes'1. Thus, most iron and aquatic humus in the post-marsh Williamson River are in the 0.025 ?m size fraction. Presumably, other trace metals would be similarly affected. Klamath Marsh serves as an important source of biologically derived solutes such as amino acids and sugars. Fractionation studies have shown that amino acids are almost exclusively humic-bound in the Will-iamson River system, while sugars may be present as either polysacchar-ides (PS) or humic-bound saccharides (HS). The PS/HS ratio may reflect the relative importance of autochthonous and allochthonous sources of sugars. Major solute composition strongly indicates that ground waters flowing into the pre-marsh Williamson River and the Sprague River are derived from a different source than are ground waters which enter the post-marsh Williamson River from Big Springs, Spring Creek, and from unidentified springs below Klamath Marsh. Nutrient concentrations (H4SiO4, NO3, PO43) are significantly higher in spring waters than elsewhere in the system. While nitrate levels (3-11 ?m) were somewhat low, phosphate levels (1-3 ?m) were quite high throughout the Williamson River system. There was some evidence for nitrogen limitation of algal growth in the pre-marsh Williamson River. While Fragilaria construens was dominant throughout the Williamson River system, several Navicula spp. were restricted to the pre-marsh Williamson River and several Fragilaria spp. and Nitzschia, spp. were found only in the post-marsh Williamson River. In Upper Klamath Lake, Stephanodiscus astrea minuta, Fragilaria construens, and Aphanizomenon flos-aquae appeared in succession, with nuisance blooms of the latter organism occurring July-November. The cessation of flow of humic-rich water from Klamath Marsh during the summer months drastically decreased the flux of aquatic humus, iron, amino acids, and other marsh-derived solutes in the post-marsh Williamson River. At the time of cessation of flow from Klamath Marsh, nuisance blooms of Aphanizomenon flos-aquae appeared in Upper Klamath Lake. Furthermore, when flow from the marsh was re-established with the first major winter rains in November or December, Aphanizomenon flos-aquae abruptly ceased to grow in Upper Klamath Lake. Further studies are planned to determine whether this correlation is causal or coincidental.

652. [Image] Oversight field hearing on the Endangered Species Act 30 years later : the Klamath Project : oversight field hearing before the Subcommittee on Water and Power of the Committee on Resources, House of Representatives, One Hundred Eighth Congress, second session, Saturday, July 17, 2004, in Klamath Falls, Oregon


	"Serial no. 108-104."
	Citation Citation Citation Abstract Copy Title: Oversight field hearing on the Endangered Species Act 30 years later : the Klamath Project : oversight field hearing before the Subcommittee on Water and Power of the Committee on Resources, House of Representatives, One Hundred Eighth Congress, second session, Saturday, July 17, 2004, in Klamath Falls, Oregon Author: United States. Congress. House. Committee on Resources. Subcommittee on Water and Power Year: 2005 "Serial no. 108-104." Title: Oversight field hearing on the Endangered Species Act 30 years later : the Klamath Project : oversight field hearing before the Subcommittee on Water and Power of the Committee on Resources, House of Representatives, One Hundred Eighth Congress, second session, Saturday, July 17, 2004, in Klamath Falls, Oregon Author: United States. Congress. House. Committee on Resources. Subcommittee on Water and Power Year: 2005 "Serial no. 108-104."

653. [Image] Historical landscape overview of the upper Klamath River Canyon of Oregon and California


	"Submitted to Klamath Falls Resource Area, Bureau of Land Management, Lakeview District, Klamath Falls, Oregon." ; "Contract no.: HAP032021."; Includes bibliographical references (p. 178-200)
	Citation Citation Citation Abstract Copy Title: Historical landscape overview of the upper Klamath River Canyon of Oregon and California Author: Beckham, Stephen Dow Year: 2006, 2008, 2007 "Submitted to Klamath Falls Resource Area, Bureau of Land Management, Lakeview District, Klamath Falls, Oregon." ; "Contract no.: HAP032021."; Includes bibliographical references (p. 178-200) Title: Historical landscape overview of the upper Klamath River Canyon of Oregon and California Author: Beckham, Stephen Dow Year: 2006, 2008, 2007 "Submitted to Klamath Falls Resource Area, Bureau of Land Management, Lakeview District, Klamath Falls, Oregon." ; "Contract no.: HAP032021."; Includes bibliographical references (p. 178-200)

654. [Image] Histopathological changes in gills of Lost River suckers (Deltistes luxatus) exposed to elevated ammonia and elevated pH


	Lease, Hilary M., Histopathological Changes in Gills of Lost River Suckers (Deltistes luxatus) Exposed to Elevated Ammonia and Elevated pH, M.S., Department of Zoology and Physiology, December, 2000. ...
	Citation Citation Citation Abstract Copy Title: Histopathological changes in gills of Lost River suckers (Deltistes luxatus) exposed to elevated ammonia and elevated pH Author: Lease, Hilary Marian Year: 2000, 2008, 2005 Lease, Hilary M., Histopathological Changes in Gills of Lost River Suckers (Deltistes luxatus) Exposed to Elevated Ammonia and Elevated pH, M.S., Department of Zoology and Physiology, December, 2000. The Lost River sucker {Deltistes luxatus) is a federally listed, endangered fish species endemic to Upper Klamath Lake?a large, shallow hypereutrophic lake in southern Oregon. Sucker population declines in the lake over the past few decades are thought to be partly attributable to extreme water quality conditions, including elevated ammonia concentrations and elevated pH, that occur during summer cyanobacterial blooms. I analyzed structural changes in gills of larval Lost River suckers after they were exposed to elevated pH and elevated ammonia concentrations in chronic toxicity tests conducted in the laboratory. Histopathological changes in sucker lamellae were observed at ammonia concentrations that did not significantly decrease survival, growth, whole-body ion content, or swimming performance. Structural changes that I evaluated included O2 diffusion distance, lamellar thickness, hyperplasic and hypertrophic mucous cells, and infiltration of white blood cells into the lymphatic space. The increases in diffusion distance and lamellar thickness were statistically significant (P < 0.05). These gill changes are indicative of potentially compromised respiratory and ionoregulatory capacity. Because in this species gill structural changes appear to be a more sensitive indicator of stress in eutrophic water quality conditions than are the more traditional sublethal indices, gill histopathology might be useful for monitoring the health of Lost River suckers in Upper Klamath Lake. Title: Histopathological changes in gills of Lost River suckers (Deltistes luxatus) exposed to elevated ammonia and elevated pH Author: Lease, Hilary Marian Year: 2000, 2008, 2005 Lease, Hilary M., Histopathological Changes in Gills of Lost River Suckers (Deltistes luxatus) Exposed to Elevated Ammonia and Elevated pH, M.S., Department of Zoology and Physiology, December, 2000. The Lost River sucker {Deltistes luxatus) is a federally listed, endangered fish species endemic to Upper Klamath Lake?a large, shallow hypereutrophic lake in southern Oregon. Sucker population declines in the lake over the past few decades are thought to be partly attributable to extreme water quality conditions, including elevated ammonia concentrations and elevated pH, that occur during summer cyanobacterial blooms. I analyzed structural changes in gills of larval Lost River suckers after they were exposed to elevated pH and elevated ammonia concentrations in chronic toxicity tests conducted in the laboratory. Histopathological changes in sucker lamellae were observed at ammonia concentrations that did not significantly decrease survival, growth, whole-body ion content, or swimming performance. Structural changes that I evaluated included O2 diffusion distance, lamellar thickness, hyperplasic and hypertrophic mucous cells, and infiltration of white blood cells into the lymphatic space. The increases in diffusion distance and lamellar thickness were statistically significant (P < 0.05). These gill changes are indicative of potentially compromised respiratory and ionoregulatory capacity. Because in this species gill structural changes appear to be a more sensitive indicator of stress in eutrophic water quality conditions than are the more traditional sublethal indices, gill histopathology might be useful for monitoring the health of Lost River suckers in Upper Klamath Lake.