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371. [Image] The geology and petrography of Crater lake national park


	167, iii p.; xix pl. (incl. 2 maps); Geology by J.S. Diller; Petrography by H.B. Patton; 35.00S
	Citation Citation Citation Abstract Copy Title: The geology and petrography of Crater lake national park Author: Diller, Joseph Silas; Patton, Horace Bushnell Year: 1902, 2006 167, iii p.; xix pl. (incl. 2 maps); Geology by J.S. Diller; Petrography by H.B. Patton; 35.00S Title: The geology and petrography of Crater lake national park Author: Diller, Joseph Silas; Patton, Horace Bushnell Year: 1902, 2006 167, iii p.; xix pl. (incl. 2 maps); Geology by J.S. Diller; Petrography by H.B. Patton; 35.00S

372. [Image] Relation between selected water-quality variables and lake level in Upper Klamath and Agency Lakes, Oregon


	Relation Between Selected Water-Quality Constituents and Lake Stage in Upper Klamath and Agency Lakes, Oregon By Tamara M. Wood, Gregory J. Fuhrer, and Jennifer L. Morace SUMMARY Upper Klamath Lake is ...
	Citation Citation Citation Abstract Copy Title: Relation between selected water-quality variables and lake level in Upper Klamath and Agency Lakes, Oregon Author: Wood, Tamara M. Year: 1996, 2005, 2004 Relation Between Selected Water-Quality Constituents and Lake Stage in Upper Klamath and Agency Lakes, Oregon By Tamara M. Wood, Gregory J. Fuhrer, and Jennifer L. Morace SUMMARY Upper Klamath Lake is a large (140 square-mile), shallow (mean depth about 8 ft) lake in south-central Oregon that the historical record indicates has been eutrophic since its discovery by non-Native Americans. In recent decades, however, the lake has had annual occurrences of near-monoculture blooms of the blue-green alga Aphanizomenon flos-aquae. In 1988 two sucker species endemic to the lake, the Lost River sucker (Deltistes luxatus) and the shortnose sucker (Chasmistes brevirostris), were listed as endangered by the U.S. Fish and Wildlife Service, and it has been proposed that the poor water quality conditions associated with extremely long and productive blooms are contributing to the decline of those species. It has also been proposed that the low lake levels made possible by the construction of a dam at the outlet from the lake in 1921 have contributed to worsening water quality through a variety of possible mechanisms (Jacob Kann, Klamath Tribes, written com-mun., 1995). One such mechanism would be an increase in internal phosphorus loading from resuspended sediments (Jacoby and others, 1982), resulting from an increase in bottom shear stresses at lower lake levels (Laenen and LeTourneau, 1996), leading in turn to more intense algal blooms. Another possible mechanism is an earlier triggering of algal blooms. When early spring lake levels are low, greater light intensity at the sediment surface might speed recruitment of algal cells from the sediments. Sediment recruitment has been shown to be an important contributor to water column biomass increases in A. flos aquae (Barbiero and Kann, 1994) and Gloeotrichia echinulata (Barbiero, 1993). An earlier bloom could result in poor water quality conditions occurring earlier in the year, when young-of-the-year fish may be more susceptible to those conditions. Lake level can also influence water quality directly. An increased frequency of sediment resuspension at lower lake levels could increase chemical and biological oxygen demand, resulting in decreased dissolved oxygen concentrations. Sediment oxygen demand also may be enhanced at lower lake levels because it is concentrated over a smaller volume of water. Some compensation for increased oxygen demand at lower lake levels might be provided by increased reaeration, if the water column mixes from top to bottom more frequently. Based on the analysis of data that they have been collecting for several years, the Klamath Tribes recently recommended that the Bureau of Reclamation (Reclamation) modify the operating plan for the dam to make the minimum lake levels for the June-August period more closely resemble pre-dam conditions (Jacob Kann, written commun., 1995). The U.S. Geological Survey (USGS) was asked to analyze the available data for the lake and to assess whether the evidence exists to conclude that year-to-year differences in certain lake water-quality variables are related to year-to-year differences in lake level. The results of the analysis will be used as scientific input in the process of developing an operating plan for the Link River Dam. Datasets Two water-quality datasets were analyzed. The first was a series of hourly records of pH, dissolved oxygen, and water temperature, each of approximately a week's duration. The records were collected at 3 sites over 3 years, 1992 through 1994, with enough consistency to define the seasonal patterns. This dataset provided information about the diel extremes in dissolved oxygen and pH and the seasonal pattern in the diel cycle, but measurements were limited to a depth of 1 m(3.28 ft). The second dataset was a set of depth profiles of pH and dissolved oxygen and concurrent depth-integrated samples for nutrients and chlo-rophyll-a. The profiles were collected at approximately biweekly intervals at nine sites (seven in Upper Klamath and two in Agency Lake) over the 5 years 1990 through 1994. These depth profiles provided information on the depth-dependence of dissolved oxygen and pH, and allowed more extensive year-to-year comparisons than did the hourly records. Because measurements were made at each site only once during the sampling day, however, they did not capture the daily extremes in water quality. Lake level is measured daily by the USGS at three sites around the lake: Rocky Point, Rattlesnake Point, and near the city of Klamath Falls. These daily measurements are then used to compute a spatially weighted average of the lake level that is reported in the USGS annual Water-Data Report for Oregon. The average lake levels were used in this report. Two climatic datasets were used in this report; both were collected at the Klamath Falls airport. Air temperature was recorded as a daily maximum and daily minimum value. Cloud cover was quantized on a daily basis into one of seven levels. Because the focus of this study was primarily to examine possible relations between water quality and lake level, the lake level data provide an important context for the discussions that follow. Title: Relation between selected water-quality variables and lake level in Upper Klamath and Agency Lakes, Oregon Author: Wood, Tamara M. Year: 1996, 2005, 2004 Relation Between Selected Water-Quality Constituents and Lake Stage in Upper Klamath and Agency Lakes, Oregon By Tamara M. Wood, Gregory J. Fuhrer, and Jennifer L. Morace SUMMARY Upper Klamath Lake is a large (140 square-mile), shallow (mean depth about 8 ft) lake in south-central Oregon that the historical record indicates has been eutrophic since its discovery by non-Native Americans. In recent decades, however, the lake has had annual occurrences of near-monoculture blooms of the blue-green alga Aphanizomenon flos-aquae. In 1988 two sucker species endemic to the lake, the Lost River sucker (Deltistes luxatus) and the shortnose sucker (Chasmistes brevirostris), were listed as endangered by the U.S. Fish and Wildlife Service, and it has been proposed that the poor water quality conditions associated with extremely long and productive blooms are contributing to the decline of those species. It has also been proposed that the low lake levels made possible by the construction of a dam at the outlet from the lake in 1921 have contributed to worsening water quality through a variety of possible mechanisms (Jacob Kann, Klamath Tribes, written com-mun., 1995). One such mechanism would be an increase in internal phosphorus loading from resuspended sediments (Jacoby and others, 1982), resulting from an increase in bottom shear stresses at lower lake levels (Laenen and LeTourneau, 1996), leading in turn to more intense algal blooms. Another possible mechanism is an earlier triggering of algal blooms. When early spring lake levels are low, greater light intensity at the sediment surface might speed recruitment of algal cells from the sediments. Sediment recruitment has been shown to be an important contributor to water column biomass increases in A. flos aquae (Barbiero and Kann, 1994) and Gloeotrichia echinulata (Barbiero, 1993). An earlier bloom could result in poor water quality conditions occurring earlier in the year, when young-of-the-year fish may be more susceptible to those conditions. Lake level can also influence water quality directly. An increased frequency of sediment resuspension at lower lake levels could increase chemical and biological oxygen demand, resulting in decreased dissolved oxygen concentrations. Sediment oxygen demand also may be enhanced at lower lake levels because it is concentrated over a smaller volume of water. Some compensation for increased oxygen demand at lower lake levels might be provided by increased reaeration, if the water column mixes from top to bottom more frequently. Based on the analysis of data that they have been collecting for several years, the Klamath Tribes recently recommended that the Bureau of Reclamation (Reclamation) modify the operating plan for the dam to make the minimum lake levels for the June-August period more closely resemble pre-dam conditions (Jacob Kann, written commun., 1995). The U.S. Geological Survey (USGS) was asked to analyze the available data for the lake and to assess whether the evidence exists to conclude that year-to-year differences in certain lake water-quality variables are related to year-to-year differences in lake level. The results of the analysis will be used as scientific input in the process of developing an operating plan for the Link River Dam. Datasets Two water-quality datasets were analyzed. The first was a series of hourly records of pH, dissolved oxygen, and water temperature, each of approximately a week's duration. The records were collected at 3 sites over 3 years, 1992 through 1994, with enough consistency to define the seasonal patterns. This dataset provided information about the diel extremes in dissolved oxygen and pH and the seasonal pattern in the diel cycle, but measurements were limited to a depth of 1 m(3.28 ft). The second dataset was a set of depth profiles of pH and dissolved oxygen and concurrent depth-integrated samples for nutrients and chlo-rophyll-a. The profiles were collected at approximately biweekly intervals at nine sites (seven in Upper Klamath and two in Agency Lake) over the 5 years 1990 through 1994. These depth profiles provided information on the depth-dependence of dissolved oxygen and pH, and allowed more extensive year-to-year comparisons than did the hourly records. Because measurements were made at each site only once during the sampling day, however, they did not capture the daily extremes in water quality. Lake level is measured daily by the USGS at three sites around the lake: Rocky Point, Rattlesnake Point, and near the city of Klamath Falls. These daily measurements are then used to compute a spatially weighted average of the lake level that is reported in the USGS annual Water-Data Report for Oregon. The average lake levels were used in this report. Two climatic datasets were used in this report; both were collected at the Klamath Falls airport. Air temperature was recorded as a daily maximum and daily minimum value. Cloud cover was quantized on a daily basis into one of seven levels. Because the focus of this study was primarily to examine possible relations between water quality and lake level, the lake level data provide an important context for the discussions that follow.

373. [Image] Klamath River fish die-off, September 2002 : causative factors of mortality


	Executive Summary This report provides information describing the biological, hydrological, meteorological, and water quality conditions associated with the die-off of an estimated 34,056 fish in the Klamath ...
	Citation Citation Citation Abstract Copy Title: Klamath River fish die-off, September 2002 : causative factors of mortality Author: Guillen, George Year: 2003, 2005, 2004 Executive Summary This report provides information describing the biological, hydrological, meteorological, and water quality conditions associated with the die-off of an estimated 34,056 fish in the Klamath River, California in September 2002. The proximate cause of death was heavy infections of two fish pathogens, Ich and columnaris. However, given that these ubiquitous pathogens are normally found in the Klamath River, additional factors must have played a role for them to have become lethal. It is our conclusion based on multiple lines of evidence that the fish die-off in the lower Klamath River in 2002 was a result of a combination of factors that began with an early peak in the return of a large run of fall Chinook salmon. Low river discharges apparently did not provide suitable attraction flows for migrating adult salmon, resulting in large numbers of fish congregating in the warm waters of the lower River. The high density offish, low discharges, warm water temperatures, and possible extended residence time of salmon created optimal conditions for parasite proliferation and precipitated an epizootic of Ich and columnaris. Based on a review of available literature and historical records, this was the largest known pre-spawning adult salmonid die-off recorded for the Klamath River and possibly the Pacific coast. Title: Klamath River fish die-off, September 2002 : causative factors of mortality Author: Guillen, George Year: 2003, 2005, 2004 Executive Summary This report provides information describing the biological, hydrological, meteorological, and water quality conditions associated with the die-off of an estimated 34,056 fish in the Klamath River, California in September 2002. The proximate cause of death was heavy infections of two fish pathogens, Ich and columnaris. However, given that these ubiquitous pathogens are normally found in the Klamath River, additional factors must have played a role for them to have become lethal. It is our conclusion based on multiple lines of evidence that the fish die-off in the lower Klamath River in 2002 was a result of a combination of factors that began with an early peak in the return of a large run of fall Chinook salmon. Low river discharges apparently did not provide suitable attraction flows for migrating adult salmon, resulting in large numbers of fish congregating in the warm waters of the lower River. The high density offish, low discharges, warm water temperatures, and possible extended residence time of salmon created optimal conditions for parasite proliferation and precipitated an epizootic of Ich and columnaris. Based on a review of available literature and historical records, this was the largest known pre-spawning adult salmonid die-off recorded for the Klamath River and possibly the Pacific coast.

374. [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.