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• 1781. [Article] A 30-Year Record of the Isotopic Composition of Atmospheric Methane

  Methane (CH4) is one of the most important greenhouse gases after water vapor and carbon dioxide due to its high concentration and global warming potential 25 times than that of CO2 (based on a 100 year ...

  Citation × Citation Citation Abstract Copy Title: A 30-Year Record of the Isotopic Composition of Atmospheric Methane Author: Teama, Doaa Galal Mohammed Year: 2013 Methane (CH4) is one of the most important greenhouse gases after water vapor and carbon dioxide due to its high concentration and global warming potential 25 times than that of CO2 (based on a 100 year time horizon). Its atmospheric concentration has more than doubled from the preindustrial era due to anthropogenic activities such as rice cultivation, biomass burning, and fossil fuel production. However, the rate of increase of atmospheric CH4 (or the growth rate) slowed from 1980 until present. The main reason for this trend is a slowdown in the trend of CH4 sources. Measuring stable isotopes of atmospheric CH4 can constrain changes of CH4 sources. The main goal of this work is to interpret the CH4 trend from 1978-2010 in terms of its sources using measurements of CH4 mixing ratio and its isotopes. The current work presents the measurements and analysis of CH4 and its isotopes (δ13C and δD) of four air archive sample sets collected by the Oregon Graduate Institute (OGI). CH4 isotope ratios (δ13C and δD) were measured by a continuous flow isotope ratio mass spectrometer technique developed at PSU. The first set is for Cape Meares, Oregon which is the oldest and longest set and spans 1977-1999. The integrity of this sample set was evaluated by comparing between our measured CH4 mixing ratio values with those measured values by OGI and was found to be stable. Resulting CH4 seasonal cycle was evaluated from the Cape Meares data. The CH4 seasonal cycle shows a broad maximum during October-April and a minimum between July and August. The seasonal cycles of δ13C and δD have maximum values in May for δ13C and in July for δD and minimum values between September-October for δ13C and in October for δD. These results indicate a CH4 source that is more enriched January-May (e.g. biomass burning) and a source that is more depleted August-October (e.g. microbial). In addition to Cape Meares, air archive sets were analyzed from: South Pole (SPO), Samoa (SMO), Mauna Loa (MLO) 1992-1996. The presented δD measurements are unique measured values during these time periods at these stations. To obtain the long-term in isotopic CH4 from 1978-2010, other datasets of Northern Hemisphere mid-latitude sites are included with Cape Meares. These sites are Olympic Peninsula, Washington; Montaña de Oro, California; and Niwot Ridge, Colorado. The seasonal cycles of CH4 and its isotopes from the composite dataset have the same phase and amplitudes as the Cape Meares site. CH4 growth rate shows a decrease over time 1978-2010 with three main spikes in 1992, 1998, and 2003 consistent with the literature from the global trend. CH4 lifetime is estimated to 9.7 yrs. The δ13C trend in the composite data shows a slow increase from 1978-1987, a more rapid rate of change 1987-2005, and a gradual depletion during 2005-2010. The δD trend in the composite data shows a gradual increase during 1978-2001 and decrease from 2001-2005. From these results, the global CH4 emissions are estimated and show a leveling off sources 1982-2010 with two large peak anomalies in 1998 and 2003. The global average δ13C and δD of CH4 sources are estimated from measured values. The results of these calculations indicate that there is more than one source which controls the decrease in the global CH4 trend. From 1982-2001, δ13C and δD of CH4 sources becomes more depleted due to a decrease in fossil and/or biomass burning sources relative to microbial sources. From 2005-2010, δ13C of CH4 sources returns to its 1981 value. There are two significant peaks in δ13C and δD of CH4 sources in 1998 and 2003 due to the wildfire emissions in boreal areas and in Europe. Title: A 30-Year Record of the Isotopic Composition of Atmospheric Methane Author: Teama, Doaa Galal Mohammed Year: 2013 Methane (CH4) is one of the most important greenhouse gases after water vapor and carbon dioxide due to its high concentration and global warming potential 25 times than that of CO2 (based on a 100 year time horizon). Its atmospheric concentration has more than doubled from the preindustrial era due to anthropogenic activities such as rice cultivation, biomass burning, and fossil fuel production. However, the rate of increase of atmospheric CH4 (or the growth rate) slowed from 1980 until present. The main reason for this trend is a slowdown in the trend of CH4 sources. Measuring stable isotopes of atmospheric CH4 can constrain changes of CH4 sources. The main goal of this work is to interpret the CH4 trend from 1978-2010 in terms of its sources using measurements of CH4 mixing ratio and its isotopes. The current work presents the measurements and analysis of CH4 and its isotopes (δ13C and δD) of four air archive sample sets collected by the Oregon Graduate Institute (OGI). CH4 isotope ratios (δ13C and δD) were measured by a continuous flow isotope ratio mass spectrometer technique developed at PSU. The first set is for Cape Meares, Oregon which is the oldest and longest set and spans 1977-1999. The integrity of this sample set was evaluated by comparing between our measured CH4 mixing ratio values with those measured values by OGI and was found to be stable. Resulting CH4 seasonal cycle was evaluated from the Cape Meares data. The CH4 seasonal cycle shows a broad maximum during October-April and a minimum between July and August. The seasonal cycles of δ13C and δD have maximum values in May for δ13C and in July for δD and minimum values between September-October for δ13C and in October for δD. These results indicate a CH4 source that is more enriched January-May (e.g. biomass burning) and a source that is more depleted August-October (e.g. microbial). In addition to Cape Meares, air archive sets were analyzed from: South Pole (SPO), Samoa (SMO), Mauna Loa (MLO) 1992-1996. The presented δD measurements are unique measured values during these time periods at these stations. To obtain the long-term in isotopic CH4 from 1978-2010, other datasets of Northern Hemisphere mid-latitude sites are included with Cape Meares. These sites are Olympic Peninsula, Washington; Montaña de Oro, California; and Niwot Ridge, Colorado. The seasonal cycles of CH4 and its isotopes from the composite dataset have the same phase and amplitudes as the Cape Meares site. CH4 growth rate shows a decrease over time 1978-2010 with three main spikes in 1992, 1998, and 2003 consistent with the literature from the global trend. CH4 lifetime is estimated to 9.7 yrs. The δ13C trend in the composite data shows a slow increase from 1978-1987, a more rapid rate of change 1987-2005, and a gradual depletion during 2005-2010. The δD trend in the composite data shows a gradual increase during 1978-2001 and decrease from 2001-2005. From these results, the global CH4 emissions are estimated and show a leveling off sources 1982-2010 with two large peak anomalies in 1998 and 2003. The global average δ13C and δD of CH4 sources are estimated from measured values. The results of these calculations indicate that there is more than one source which controls the decrease in the global CH4 trend. From 1982-2001, δ13C and δD of CH4 sources becomes more depleted due to a decrease in fossil and/or biomass burning sources relative to microbial sources. From 2005-2010, δ13C of CH4 sources returns to its 1981 value. There are two significant peaks in δ13C and δD of CH4 sources in 1998 and 2003 due to the wildfire emissions in boreal areas and in Europe. Close

• 1782. [Article] Variation in the timing of coho salmon (Oncorhynchus kisutch) migration and spawning relative to river discharge and temperature

  Coho salmon (Oncorhynchus kisutch) migration and spawning are unique components of the salmon life cycle because they require synchrony of behavior with other individuals as well as with acceptable fluvial ...

  Citation × Citation Citation Abstract Copy Title: Variation in the timing of coho salmon (Oncorhynchus kisutch) migration and spawning relative to river discharge and temperature Author: LovellFord, Rachel Coho salmon (Oncorhynchus kisutch) migration and spawning are unique components of the salmon life cycle because they require synchrony of behavior with other individuals as well as with acceptable fluvial conditions. As with other organisms that exhibit group mating behavior, it is likely that environmental cues trigger coho salmon movement to spawning grounds. These cues may also provide usable habitat for migration and spawning. River discharge, temperature, and length of day have long been assumed to be the environmental cues which trigger migration and spawning of coho salmon as coho return within the same season each year to spawn. Hatchery studies have also shown that the timing of reproductive behavior is heritable. If this heritability is determined by the fluvial conditions of the spawning grounds, then a predictable relationship should exist between reproductive behavior and the hydrologic and thermal regimes. Surprisingly, no defensible correlations between discharge thresholds and spawning or migrating activity have been identified for naturally reproducing coho salmon. Thermal, velocity, and depth limitations have been identified for coho salmon, but these values have not been examined in combination or within the context of a hydrologic and thermal regime. This study compares interannual patterns in the timing of coho mid-river migration in the North Umqua (180 km up river from the estuary) and the initiation of spawn timing in the Smith River basins (Oregon) with river discharge and water temperature data to ascertain whether these behaviors are driven by fluvial conditions. Additionally, we used this data to identify the window over which most migration and spawning takes place in our test systems. On the North Umpqua, coho salmon mid-river migration initiated (first 5% of migrants) after summer peak temperatures and following a threshold average daily temperature of 18 C°, but before fall storm events occurred. In most years, approximately 75% of the migrating coho salmon have moved past the Winchester Dam before fall storms initiated and when discharge remained less than the 11 year average for the month of November, more similar to summer than winter flow levels. Additionally, characteristic lengths and numbers of peaks within the distribution of annual migrations were attributable to the generational cohort that the migration belonged to despite the similarity in population size across all years. These patterns in the distribution of generational cohorts suggest an inherited timing response as well as highlight cohorts which may contain diminished sub-populations. The initiation of coho salmon spawning appears limited both by a thermal threshold of 12 C° in all basins, as well as by a minimal discharge threshold, which is unique to each stream. Continued spawning activity occurs as discharge remains elevated from fall levels. It is also notable that there was no statistical difference in the date of the initiation of spawning within each basin in a given year or across years at a given site. Together, these studies highlight the important role that the coho salmon genome plays in reproductive timing as well as the ways that fluvial thresholds limit reproductive behavior in time. Coho have survived because of their genome has been resilient when faced with environmental change. Future work should consider variability in fluvial conditions relative to coho salmon phenotypic plasticity over time. Coho salmon phenotypic plasticity will determine whether the rate of change of the hydrologic and thermal regimes important to coho salmon survival outpaces the coho’s ability to adapt. This study contributed to this future work by establishing baseline relationships between the behavior of a threatened species and measurable environmental thresholds. Title: Variation in the timing of coho salmon (Oncorhynchus kisutch) migration and spawning relative to river discharge and temperature Author: LovellFord, Rachel Coho salmon (Oncorhynchus kisutch) migration and spawning are unique components of the salmon life cycle because they require synchrony of behavior with other individuals as well as with acceptable fluvial conditions. As with other organisms that exhibit group mating behavior, it is likely that environmental cues trigger coho salmon movement to spawning grounds. These cues may also provide usable habitat for migration and spawning. River discharge, temperature, and length of day have long been assumed to be the environmental cues which trigger migration and spawning of coho salmon as coho return within the same season each year to spawn. Hatchery studies have also shown that the timing of reproductive behavior is heritable. If this heritability is determined by the fluvial conditions of the spawning grounds, then a predictable relationship should exist between reproductive behavior and the hydrologic and thermal regimes. Surprisingly, no defensible correlations between discharge thresholds and spawning or migrating activity have been identified for naturally reproducing coho salmon. Thermal, velocity, and depth limitations have been identified for coho salmon, but these values have not been examined in combination or within the context of a hydrologic and thermal regime. This study compares interannual patterns in the timing of coho mid-river migration in the North Umqua (180 km up river from the estuary) and the initiation of spawn timing in the Smith River basins (Oregon) with river discharge and water temperature data to ascertain whether these behaviors are driven by fluvial conditions. Additionally, we used this data to identify the window over which most migration and spawning takes place in our test systems. On the North Umpqua, coho salmon mid-river migration initiated (first 5% of migrants) after summer peak temperatures and following a threshold average daily temperature of 18 C°, but before fall storm events occurred. In most years, approximately 75% of the migrating coho salmon have moved past the Winchester Dam before fall storms initiated and when discharge remained less than the 11 year average for the month of November, more similar to summer than winter flow levels. Additionally, characteristic lengths and numbers of peaks within the distribution of annual migrations were attributable to the generational cohort that the migration belonged to despite the similarity in population size across all years. These patterns in the distribution of generational cohorts suggest an inherited timing response as well as highlight cohorts which may contain diminished sub-populations. The initiation of coho salmon spawning appears limited both by a thermal threshold of 12 C° in all basins, as well as by a minimal discharge threshold, which is unique to each stream. Continued spawning activity occurs as discharge remains elevated from fall levels. It is also notable that there was no statistical difference in the date of the initiation of spawning within each basin in a given year or across years at a given site. Together, these studies highlight the important role that the coho salmon genome plays in reproductive timing as well as the ways that fluvial thresholds limit reproductive behavior in time. Coho have survived because of their genome has been resilient when faced with environmental change. Future work should consider variability in fluvial conditions relative to coho salmon phenotypic plasticity over time. Coho salmon phenotypic plasticity will determine whether the rate of change of the hydrologic and thermal regimes important to coho salmon survival outpaces the coho’s ability to adapt. This study contributed to this future work by establishing baseline relationships between the behavior of a threatened species and measurable environmental thresholds. Close

• 1783. [Image] Bowling green

  	Fort Amsterdam was erected on the site of the present Custom House facing Bowling Green. At this time the island ended there. The extreme lower edge, occupied now by streets to South Ferry and the Battery ...
  	Citation × Citation Citation Abstract Copy Title: Bowling green Year: 1900 Fort Amsterdam was erected on the site of the present Custom House facing Bowling Green. At this time the island ended there. The extreme lower edge, occupied now by streets to South Ferry and the Battery Park district, has been constructed in recent times. Space has also been made along the eastern and western edge of the island. At the beginning of the Dutch occupation the northern limit of the little settlement which looked out upon a wilderness was at Wall Street. Along this northern limit a wooden wall or palisade was built for protection against wild animals and Indians. This was first built by felling trees and piling their trunks out in a row along the path. A few years later Peter Stuyvesant who was governor general of the island ordered the inhabitants to build more substantial barrier. It was from this wooden wall that Wall Street gets its name. Now Wall Street is a narrow canyon bordered on either side by towering skyscrappers through which flows the wealth not only of this country but of the world. This old wall stood until about 1699 when it was torn down. Meanwhile, it had confined the growth of the settlement to a very small area and retarded the orderly development of streets and roads. This is why the lower part of Manhattan today is full of short, crooked and narrow streets. One of the last streets laid out in the old enclosure was called New Street, and today if you go from Broadway east down Wall Street the first street that you will pass on your right will be New Street. Many of these old streets still follow the old cow paths. Not a one of the original buildings in this oldest part of the city remains. All that is left to remind the visitor of the past is an occasional tablet placed on the site of the most interesting of these early incidents. Perhaps this but emphasizes a trait that is especially American--the placing of trade and commerce or money above sentiment. Some time we Americans will awake to the fact that after all there are some things of more worth than money. Here in the West I hope that the realization of this may not come too late--after we have destroyed our forests, killed our wild game, strewn newspapers, tobacco boxes and egg shells over our mountains and made our rivers dumping places for our sewers. You have probably cherished many sentimental pictures of the beautiful and picturesque Hudson River. It is still beautiful from a distance, but the cities built along its banks have had no respect for its beauty and have made it filthy with their dumpings. A close up view of it from a ferry is frequently a nauseating sight to a sensitive person. Can't we take a lesson from it in our treatment of our own beautiful rivers? In addition to the public buildings erected on this lower portion of the island for trade and business, there came to be beautiful homes of the most wealthy citizens. These were along State Street and in the vicinity of Broadway. Stephen Whitney, inventor of the cotton gin and others lived here. Stately houses they were for their day and yet entirely innocent of such present-day conveniences as running water, gas or steam heat. Open fireplaces furnished all the heat. During the Civil War troops were quartered at the Battery and from that time on the character of the place changed. Homes were built further up town and the lower sites came to be replaced with business structures. In this old residence section steamship companies found location for their offices. It seems to be a characteristic step in New York City's growth that as people are crowded from their homes by the encroaching of commerce and trade, business first appropriates these old homes and then gradually replaces them with modern business buildings. This is what has happened to the lower section of the city and what may still be seen happening in the up town districts. The steamship companies still have their offices in this early residence district, but there is a far cry from the residences of 200 years ago and the offices that one sees today, on what is comonly "Steamship Row". Title: Bowling green Year: 1900 Fort Amsterdam was erected on the site of the present Custom House facing Bowling Green. At this time the island ended there. The extreme lower edge, occupied now by streets to South Ferry and the Battery Park district, has been constructed in recent times. Space has also been made along the eastern and western edge of the island. At the beginning of the Dutch occupation the northern limit of the little settlement which looked out upon a wilderness was at Wall Street. Along this northern limit a wooden wall or palisade was built for protection against wild animals and Indians. This was first built by felling trees and piling their trunks out in a row along the path. A few years later Peter Stuyvesant who was governor general of the island ordered the inhabitants to build more substantial barrier. It was from this wooden wall that Wall Street gets its name. Now Wall Street is a narrow canyon bordered on either side by towering skyscrappers through which flows the wealth not only of this country but of the world. This old wall stood until about 1699 when it was torn down. Meanwhile, it had confined the growth of the settlement to a very small area and retarded the orderly development of streets and roads. This is why the lower part of Manhattan today is full of short, crooked and narrow streets. One of the last streets laid out in the old enclosure was called New Street, and today if you go from Broadway east down Wall Street the first street that you will pass on your right will be New Street. Many of these old streets still follow the old cow paths. Not a one of the original buildings in this oldest part of the city remains. All that is left to remind the visitor of the past is an occasional tablet placed on the site of the most interesting of these early incidents. Perhaps this but emphasizes a trait that is especially American--the placing of trade and commerce or money above sentiment. Some time we Americans will awake to the fact that after all there are some things of more worth than money. Here in the West I hope that the realization of this may not come too late--after we have destroyed our forests, killed our wild game, strewn newspapers, tobacco boxes and egg shells over our mountains and made our rivers dumping places for our sewers. You have probably cherished many sentimental pictures of the beautiful and picturesque Hudson River. It is still beautiful from a distance, but the cities built along its banks have had no respect for its beauty and have made it filthy with their dumpings. A close up view of it from a ferry is frequently a nauseating sight to a sensitive person. Can't we take a lesson from it in our treatment of our own beautiful rivers? In addition to the public buildings erected on this lower portion of the island for trade and business, there came to be beautiful homes of the most wealthy citizens. These were along State Street and in the vicinity of Broadway. Stephen Whitney, inventor of the cotton gin and others lived here. Stately houses they were for their day and yet entirely innocent of such present-day conveniences as running water, gas or steam heat. Open fireplaces furnished all the heat. During the Civil War troops were quartered at the Battery and from that time on the character of the place changed. Homes were built further up town and the lower sites came to be replaced with business structures. In this old residence section steamship companies found location for their offices. It seems to be a characteristic step in New York City's growth that as people are crowded from their homes by the encroaching of commerce and trade, business first appropriates these old homes and then gradually replaces them with modern business buildings. This is what has happened to the lower section of the city and what may still be seen happening in the up town districts. The steamship companies still have their offices in this early residence district, but there is a far cry from the residences of 200 years ago and the offices that one sees today, on what is comonly "Steamship Row". Close

• 1784. [Image] The Klamath Project

  	"Seventh draft"; Includes bibliographical references and index
  	Citation × Citation Citation Abstract Copy Title: The Klamath Project Author: Stene, Eric A. Year: 1994, 2004 "Seventh draft"; Includes bibliographical references and index Title: The Klamath Project Author: Stene, Eric A. Year: 1994, 2004 "Seventh draft"; Includes bibliographical references and index Close

• 1785. [Article] Petrology and geochemistry of the Emigrant Pass volcanics, Nevada : implications for a magmatic-hydrothermal origin of the Carlin gold deposits

  The Emigrant Pass volcanics (EPV) are a 38.3 to 36.4 Ma calc-alkaline volcanic center that erupted andesite and dacite, and a late series of felsic dikes along the south flank of the Carlin gold district ...

  Citation × Citation Citation Abstract Copy Title: Petrology and geochemistry of the Emigrant Pass volcanics, Nevada : implications for a magmatic-hydrothermal origin of the Carlin gold deposits Author: Johnson, Curtis L. (Curtis Lawrence) The Emigrant Pass volcanics (EPV) are a 38.3 to 36.4 Ma calc-alkaline volcanic center that erupted andesite and dacite, and a late series of felsic dikes along the south flank of the Carlin gold district in north-central Nevada. The EPV includes dacite and rhyolite porphyry dikes indistinguishable from porphyry dikes associated with mineralization within the district. The volcanic rocks likely represent eruptive equivalents of deeper, unexposed Eocene plutons that may be the source of heat, fluids, and metals of Carlin-type gold deposits. New petrologic and geochemical data of the EPV are presented to test this hypothesis. The EPV are exposed over a 30 x 15 km area, have an estimated volume of 100 to >200 km³ and are divided into the early Primeaux lavas (38.1-38.3 Ma), the Mack Creek lavas and related intrusions (37.1-38.4 Ma), and late eruptive and hypabyssal rocks (Henry and Faulds, 1999). The Primeaux lavas are a >500 m thick sequence of pyroxene and hornblende andesite to dacite lavas and intrusions; minor pyroxene, hornblende and biotite dikes; and volcanic conglomerates. The Mack Creek lavas are a 180 m thick succession of porphyritic dacite lava flows, domes, and intrusions. Late small-volume units include the Bob Creek basaltic andesite to andesite lava (37.7 Ma) and rhyolitic to dacitic dikes (36.4-36.7 Ma). Primeaux andesite crystallized early clinopyroxene, orthopyroxene, plagioclase, and late hornblende, which suggests moderate water contents (~3 wt.%). Mack Creek dacite and late rhyolite-dacite dikes crystallized hornblende and biotite early, attesting to high water contents (>4 wt.%). Early Primeaux andesites contain abundant magnetite and sparse ilmenite, whereas Mack Creek dacites and late rhyolite-dacite dikes contain magnetite and local titanite. This mineralogy is consistent with the evolution of magmas from early moderately oxidized conditions to late strongly oxidized conditions (fO2 ≥ NNO+2) similar to porphyry copper magmas (Dilles, 1987). Carlin plagioclase-biotite-hornblende dacite porphyry dikes associated with gold ores yielded four new LA-ICP-MS U/Pb zircon ages (36.7±1.8, 38.8±1.7, 39.2±1.6, 39.4±1.5 Ma), overlapping in age with the earliest EPV eruptions. Two additional U/Pb zircon ages were obtained on a coarsely porphyritic dacite lava of the Mack Creek sequence (37.10±0.54 Ma), and a porphyritic dacite lava (148.2±2.3 Ma) likely of the Frenchie Creek Volcanics at the southern terminus of the EPV. All analyzed Carlin porphyries contain zircons with EuN/EuN* versus Hf arrays and EuN/EuN* > 0.4 similar to porphyry copper plutons (Dilles et al., 2015) and the 36 Ma Battle Mountain granodiorite porphyry associated with Cu(Au) ores (Farmer, 2013). Abundant partially melted granite xenoliths in EPV rocks indicate assimilation of crust during magma generation, whereas incompletely mixed magmas with differing mineralogy along with abundantly sieved plagioclase and resorbed amphibole indicate magma mixing processes. The andesites and dacites have high-K to shoshonitic compositions similar to subduction-related arc magmas. Whereas most major elements display simple linear correlations with silica, interpreted to indicate mixing, the MgO and Cr of most samples abruptly decrease with increased silica consistent with crystal fractionation. Dacites of the Mack Creek have elevated MgO and Cr compared to Primeaux andesites and Bob Creek basaltic-andesites, consistent with mixing of primitive basaltic andesite or andesite with rhyolite. Enrichment in Rb, Ba, and Cs indicate crustal additions compared to average arc magmas, whereas elevated V/Sc (1.4-17.3; Mean: 8.9) and Sr/Y (16.6-49.6; Mean: 36.1) ratios are similar to mineralizing porphyry Cu (Au) magmas (Loucks, 2014). Hornblende compositions from four samples are bimodal and include both low-Al and high-Al amphiboles now commonly recognized in arc suites (Aucanquilcha, Chile: Walker et al., 2013; Yanacocha, Peru: Chambefort et al., 2013). Using the Ridolfi et al. (2010) formulation, the low-Al hornblende crystallized at 820-890°C and 100-250 MPa (4-10 km depth), whereas high-Al amphibole crystallized at about 900-980°C and possibly greater depths. Electron microprobe studies of magmatic sulfide inclusions indicate monosulfide solid solution (MSS, pyrrhotite at low temperatures) was the dominant magmatic sulfide species with minor (n=4 of 119 analyses) intermediate solid solution (ISS, chalcopyrite at low temperatures). Sulfide contents decrease systematically as the magmas evolved from andesite-dacite-rhyolite, supporting the observation of increasing oxidation state and magmatic sulfate/sulfide ratio. Additionally, all phases of the EPV are highly depleted in whole rock Cu (<10ppm), suggesting Cu was efficiently removed during volatile exsolution at depth or alternatively was sequestered in magmatic sulfide at depth. Experimental studies of Au partitioning in intermediate composition melts indicate that the predominance of MSS over sulfide liquid or ISS is a prerequisite for forming Au-rich melts as MSS preferentially incorporates Cu over Au, thereby further enriching the Au/Cu ratio of the remaining melt (Muntean et al., 2011; Botcharnikov et al., 2013; Yi and Audetat, 2013). Muntean and others (2011) proposed a magmatic-hydrothermal fluid and metal source of the Carlin gold deposits and suggested source magmas were fundamentally enriched in Au relative to Cu as a result of MSS fractionation over ISS or sulfide liquid, which is supported by these new data on EPV magmatic sulfide inclusions. Title: Petrology and geochemistry of the Emigrant Pass volcanics, Nevada : implications for a magmatic-hydrothermal origin of the Carlin gold deposits Author: Johnson, Curtis L. (Curtis Lawrence) The Emigrant Pass volcanics (EPV) are a 38.3 to 36.4 Ma calc-alkaline volcanic center that erupted andesite and dacite, and a late series of felsic dikes along the south flank of the Carlin gold district in north-central Nevada. The EPV includes dacite and rhyolite porphyry dikes indistinguishable from porphyry dikes associated with mineralization within the district. The volcanic rocks likely represent eruptive equivalents of deeper, unexposed Eocene plutons that may be the source of heat, fluids, and metals of Carlin-type gold deposits. New petrologic and geochemical data of the EPV are presented to test this hypothesis. The EPV are exposed over a 30 x 15 km area, have an estimated volume of 100 to >200 km³ and are divided into the early Primeaux lavas (38.1-38.3 Ma), the Mack Creek lavas and related intrusions (37.1-38.4 Ma), and late eruptive and hypabyssal rocks (Henry and Faulds, 1999). The Primeaux lavas are a >500 m thick sequence of pyroxene and hornblende andesite to dacite lavas and intrusions; minor pyroxene, hornblende and biotite dikes; and volcanic conglomerates. The Mack Creek lavas are a 180 m thick succession of porphyritic dacite lava flows, domes, and intrusions. Late small-volume units include the Bob Creek basaltic andesite to andesite lava (37.7 Ma) and rhyolitic to dacitic dikes (36.4-36.7 Ma). Primeaux andesite crystallized early clinopyroxene, orthopyroxene, plagioclase, and late hornblende, which suggests moderate water contents (~3 wt.%). Mack Creek dacite and late rhyolite-dacite dikes crystallized hornblende and biotite early, attesting to high water contents (>4 wt.%). Early Primeaux andesites contain abundant magnetite and sparse ilmenite, whereas Mack Creek dacites and late rhyolite-dacite dikes contain magnetite and local titanite. This mineralogy is consistent with the evolution of magmas from early moderately oxidized conditions to late strongly oxidized conditions (fO2 ≥ NNO+2) similar to porphyry copper magmas (Dilles, 1987). Carlin plagioclase-biotite-hornblende dacite porphyry dikes associated with gold ores yielded four new LA-ICP-MS U/Pb zircon ages (36.7±1.8, 38.8±1.7, 39.2±1.6, 39.4±1.5 Ma), overlapping in age with the earliest EPV eruptions. Two additional U/Pb zircon ages were obtained on a coarsely porphyritic dacite lava of the Mack Creek sequence (37.10±0.54 Ma), and a porphyritic dacite lava (148.2±2.3 Ma) likely of the Frenchie Creek Volcanics at the southern terminus of the EPV. All analyzed Carlin porphyries contain zircons with EuN/EuN* versus Hf arrays and EuN/EuN* > 0.4 similar to porphyry copper plutons (Dilles et al., 2015) and the 36 Ma Battle Mountain granodiorite porphyry associated with Cu(Au) ores (Farmer, 2013). Abundant partially melted granite xenoliths in EPV rocks indicate assimilation of crust during magma generation, whereas incompletely mixed magmas with differing mineralogy along with abundantly sieved plagioclase and resorbed amphibole indicate magma mixing processes. The andesites and dacites have high-K to shoshonitic compositions similar to subduction-related arc magmas. Whereas most major elements display simple linear correlations with silica, interpreted to indicate mixing, the MgO and Cr of most samples abruptly decrease with increased silica consistent with crystal fractionation. Dacites of the Mack Creek have elevated MgO and Cr compared to Primeaux andesites and Bob Creek basaltic-andesites, consistent with mixing of primitive basaltic andesite or andesite with rhyolite. Enrichment in Rb, Ba, and Cs indicate crustal additions compared to average arc magmas, whereas elevated V/Sc (1.4-17.3; Mean: 8.9) and Sr/Y (16.6-49.6; Mean: 36.1) ratios are similar to mineralizing porphyry Cu (Au) magmas (Loucks, 2014). Hornblende compositions from four samples are bimodal and include both low-Al and high-Al amphiboles now commonly recognized in arc suites (Aucanquilcha, Chile: Walker et al., 2013; Yanacocha, Peru: Chambefort et al., 2013). Using the Ridolfi et al. (2010) formulation, the low-Al hornblende crystallized at 820-890°C and 100-250 MPa (4-10 km depth), whereas high-Al amphibole crystallized at about 900-980°C and possibly greater depths. Electron microprobe studies of magmatic sulfide inclusions indicate monosulfide solid solution (MSS, pyrrhotite at low temperatures) was the dominant magmatic sulfide species with minor (n=4 of 119 analyses) intermediate solid solution (ISS, chalcopyrite at low temperatures). Sulfide contents decrease systematically as the magmas evolved from andesite-dacite-rhyolite, supporting the observation of increasing oxidation state and magmatic sulfate/sulfide ratio. Additionally, all phases of the EPV are highly depleted in whole rock Cu (<10ppm), suggesting Cu was efficiently removed during volatile exsolution at depth or alternatively was sequestered in magmatic sulfide at depth. Experimental studies of Au partitioning in intermediate composition melts indicate that the predominance of MSS over sulfide liquid or ISS is a prerequisite for forming Au-rich melts as MSS preferentially incorporates Cu over Au, thereby further enriching the Au/Cu ratio of the remaining melt (Muntean et al., 2011; Botcharnikov et al., 2013; Yi and Audetat, 2013). Muntean and others (2011) proposed a magmatic-hydrothermal fluid and metal source of the Carlin gold deposits and suggested source magmas were fundamentally enriched in Au relative to Cu as a result of MSS fractionation over ISS or sulfide liquid, which is supported by these new data on EPV magmatic sulfide inclusions. Close

• 1786. [Image] Effects of water quality on growth of juvenile shortnose suckers, Chasmistes brevirostris (Catostomidae: Cypriniformes), from Upper Klamath Lake, Oregon

  	One chapter of a seven chapter annual report from 1999 examining ecological issues regarding the shortnose and Lost River sucker populations in Upper Klamath Lake and Williamson River.
  	Citation × Citation Citation Abstract Copy Title: Effects of water quality on growth of juvenile shortnose suckers, Chasmistes brevirostris (Catostomidae: Cypriniformes), from Upper Klamath Lake, Oregon Author: Oregon Cooperative Wildlife Research Unit Year: 2000, 2005 One chapter of a seven chapter annual report from 1999 examining ecological issues regarding the shortnose and Lost River sucker populations in Upper Klamath Lake and Williamson River. Title: Effects of water quality on growth of juvenile shortnose suckers, Chasmistes brevirostris (Catostomidae: Cypriniformes), from Upper Klamath Lake, Oregon Author: Oregon Cooperative Wildlife Research Unit Year: 2000, 2005 One chapter of a seven chapter annual report from 1999 examining ecological issues regarding the shortnose and Lost River sucker populations in Upper Klamath Lake and Williamson River. Close

• 1787. [Image] Bull Trout, Salvelinus Confluentus... Draft Recovery Plan, Chapter 1, Introduction...

  	EXECUTIVE SUMMARY FOR THE BULL TROUT RECOVERY PLAN Current Species Status The bull trout (Salvelinus confluentus) in the coterminous United States was listed as threatened on November 1, 1999 (64 ...
  	Citation × Citation Citation Abstract Copy Title: Bull Trout, Salvelinus Confluentus... Draft Recovery Plan, Chapter 1, Introduction... Author: U.S. Fish and Wildlife Service Year: 2003, 2008, 2005 EXECUTIVE SUMMARY FOR THE BULL TROUT RECOVERY PLAN Current Species Status The bull trout (Salvelinus confluentus) in the coterminous United States was listed as threatened on November 1, 1999 (64 FR 58910). Earlier rulemakings had listed distinct population segments of bull trout as threatened in the Columbia River, Klamath River, and Jarbidge River basins (63 FR 31647, 63 FR 42757, 64 FR 17110). Bull trout distribution, abundance, and habitat quality have declined rangewide. Several local extirpations have been documented, beginning in the 1950fs. Bull trout continue to occur the Klamath River, Columbia River, Jarbidge River, St. Mary-Belly River, and Coastal-Puget Sound, in the states of Idaho, Montana, Nevada, Oregon, and Washington. Habitat Requirements and Limiting Factors Bull trout have more specific habitat requirements than most other salmonids. Habitat components that influence bull trout distribution and abundance include water temperature, cover, channel form and stability, substrate for spawning and rearing, and migratory corridors. Bull trout are found in colder streams and require colder water than most other salmonids for incubation, juvenile rearing, and spawning. Spawning and rearing areas are often associated with cold-water springs, groundwater infiltration, and/or the coldest streams in a watershed. Throughout their lives, bull trout require complex forms of cover, including large woody debris, undercut banks, boulders, and pools. Alterations in channel form and reductions in channel stability result in habitat degradation and reduced survival of bull trout eggs and juveniles. Channel alterations may reduce the abundance and quality of side channels, stream margins, and pools, which are areas bull trout frequently inhabit. For spawning and early rearing bull trout require loose, clean gravel relatively free of fine sediments. Because bull trout have a relatively long incubation and development period within spawning gravel (greater than 200 days), transport of bedload in unstable channels may kill young bull trout. Bull trout use migratory corridors to move from spawning and rearing habitats to foraging and overwintering habitats and back. Different habitats provide bull trout with diverse resources, and migratory corridors allow local populations to connect, which may increase the potential for gene flow and support or refounding of populations. Declines in bull trout distribution and abundance are the results of combined effects of the following: habitat degradation and fragmentation, the blockage of migratory corridors, poor water quality, angler harvest and poaching, entrainment (process by which aquatic organisms are pulled through a diversion structure or other device) into diversion channels and dams, and introduced iv normative species. Specific land and water management activities that continue to depress bull trout populations and degrade habitat include dams and other diversion structures, forest management practices, livestock grazing, agriculture, road construction and maintenance, mining, and urban and rural development. Some threats to bull trout are the continuing effects of past land management activities. Organization and Development of the Recovery Plan Because bull trout in the coterminous United States are widely distributed within a large area, the recovery plan is organized into multiple chapters. This introductory chapter (Chapter 1) describes our overall recovery strategy for the species, defines recovery, and identifies recovery actions applicable for all listed bull trout in the coterminous United States. Each successive chapter focuses on bull trout in specific geographic areas (recovery units), and describes conditions, defines recovery criteria, and identifies specific recovery actions for the recovery unit. Recovery Objectives The goal of this recovery plan is to describe the actions needed to achieve the recovery of bull trout, that is, to ensure the long-term persistence of self-sustaining, complex interacting groups (or multiple local populations that may have overlapping spawning and rearing areas) of bull trout distributed across the species' native range. Recovery of bull trout will require reducing threats to the long-term persistence of populations, maintaining multiple interconnected populations of bull trout across the diverse habitats of their native range, and preserving the diversity of bull trout life-history strategies (e.g., resident or migratory forms, emigration age, spawning frequency, local habitat adaptations). To recover bull trout, the following four objectives have been identified: ? Maintain current distribution of bull trout within core areas as described in recovery unit chapters and restore distribution where recommended in recovery unit chapters. ? Maintain stable or increasing trend in abundance of bull trout. ? Restore and maintain suitable habitat conditions for all bull trout life history stages and strategies. ? Conserve genetic diversity and provide opportunity for genetic exchange. ? These objectives apply to bull trout in all recovery units. Additional objectives may be necessary to achieve recovery in some recovery units and will be identified in the respective recovery unit chapters. Recovery Criteria Criteria are established to assess whether recovery objectives are being achieved. Criteria specific to each recovery unit are defined in each recovery unit chapter. Individual chapters may contain criteria for assessing the status of bull trout and alleviation of threats that are unique to one or several recovery units. However, every recovery unit chapter will contain criteria that address the following characteristics: ? The distribution of bull trout in identified and potential local populations in all core areas within the recovery unit. ? The estimated abundance of adult bull trout within core areas in the recovery unit, expressed as either a point estimate or a range of individuals. ? The presence of stable or increasing trends for adult bull trout abundance in the recovery unit. ? The restoration of passage at specific barriers identified as inhibiting recovery. We expect recovery of bull trout to be a dynamic process occurring over time. The recovery objectives are based on our current knowledge and may be refined as more information becomes available. Some local populations of bull trout, and possibly core area populations, may be extirpated even though recovery actions are being implemented. If reestablishment of recently extirpated populations is not feasible or practical, recovery criteria for a given recovery unit will be revised on a case-by-case basis. Meeting the four recovery criteria is not intended to be precluded where localized extirpations of bull trout are offset by sufficiently strong improvements in other areas of a recovery unit in meeting the four recovery objectives. The determination of whether a distinct population segment of bull trout is recovered will rely on an analysis of the overall status of the species, threats to the species, and the adequacy of existing regulatory and conservation mechanisms. For example, it may be possible for the Columbia River Distinct Population Segment, which has 22 recovery units, to be recovered prior to all recovery unit criteria being met in all recovery units. Success in accomplishing the recovery VI criteria will be reviewed and considered for the impacts both within a recovery unit and throughout a distinct population segment. Actions Needed Specific tasks falling within the following seven categories will be necessary to initiate recovery within all recovery units: ? Protect, restore, and maintain suitable habitat conditions for bull trout. ? Prevent and reduce negative effects of normative fishes and other normative taxa on bull trout. ? Establish fisheries management goals and objectives compatible with bull trout recovery and implement practices to achieve goals. ? Characterize, conserve, and monitor genetic diversity and gene flow among local populations of bull trout. ? Conduct research and monitoring to implement and evaluate bull trout recovery activities, consistent with an adaptive management approach using feedback from implemented, site-specific recovery tasks. ? Use all available conservation programs and regulations to protect and conserve bull trout and bull trout habitats. ? Assess the implementation of bull trout recovery by recovery units and revise recovery unit plans based on evaluations. Recovery Priority Number The recovery priority number for bull trout in the coterminous United States is 9C, on a scale of 1 to 18, indicating that (1) taxonomically, these populations are distinct population segments of a species, (2) the five populations are subject to a moderate degree of threat(s), (3) the recovery potential is high, and (4) the degree of potential conflict during recovery is high. vrr Estimated Cost of Recovery The total cost estimate of recovery for bull trout in the coterminous United States is presented in the individual recovery unit chapters. The costs presented in each chapter are attributed to bull trout conservation but other species will also benefit. Date of Recovery Expected time to achieve recovery varies among recovery units because of differences in bull trout status, factors affecting bull trout, implementation and effectiveness of recovery tasks, and responses to recovery tasks. Achieving bull trout recovery in all recovery units will be a complex process that will likely take 25 years or more. vin Title: Bull Trout, Salvelinus Confluentus... Draft Recovery Plan, Chapter 1, Introduction... Author: U.S. Fish and Wildlife Service Year: 2003, 2008, 2005 EXECUTIVE SUMMARY FOR THE BULL TROUT RECOVERY PLAN Current Species Status The bull trout (Salvelinus confluentus) in the coterminous United States was listed as threatened on November 1, 1999 (64 FR 58910). Earlier rulemakings had listed distinct population segments of bull trout as threatened in the Columbia River, Klamath River, and Jarbidge River basins (63 FR 31647, 63 FR 42757, 64 FR 17110). Bull trout distribution, abundance, and habitat quality have declined rangewide. Several local extirpations have been documented, beginning in the 1950fs. Bull trout continue to occur the Klamath River, Columbia River, Jarbidge River, St. Mary-Belly River, and Coastal-Puget Sound, in the states of Idaho, Montana, Nevada, Oregon, and Washington. Habitat Requirements and Limiting Factors Bull trout have more specific habitat requirements than most other salmonids. Habitat components that influence bull trout distribution and abundance include water temperature, cover, channel form and stability, substrate for spawning and rearing, and migratory corridors. Bull trout are found in colder streams and require colder water than most other salmonids for incubation, juvenile rearing, and spawning. Spawning and rearing areas are often associated with cold-water springs, groundwater infiltration, and/or the coldest streams in a watershed. Throughout their lives, bull trout require complex forms of cover, including large woody debris, undercut banks, boulders, and pools. Alterations in channel form and reductions in channel stability result in habitat degradation and reduced survival of bull trout eggs and juveniles. Channel alterations may reduce the abundance and quality of side channels, stream margins, and pools, which are areas bull trout frequently inhabit. For spawning and early rearing bull trout require loose, clean gravel relatively free of fine sediments. Because bull trout have a relatively long incubation and development period within spawning gravel (greater than 200 days), transport of bedload in unstable channels may kill young bull trout. Bull trout use migratory corridors to move from spawning and rearing habitats to foraging and overwintering habitats and back. Different habitats provide bull trout with diverse resources, and migratory corridors allow local populations to connect, which may increase the potential for gene flow and support or refounding of populations. Declines in bull trout distribution and abundance are the results of combined effects of the following: habitat degradation and fragmentation, the blockage of migratory corridors, poor water quality, angler harvest and poaching, entrainment (process by which aquatic organisms are pulled through a diversion structure or other device) into diversion channels and dams, and introduced iv normative species. Specific land and water management activities that continue to depress bull trout populations and degrade habitat include dams and other diversion structures, forest management practices, livestock grazing, agriculture, road construction and maintenance, mining, and urban and rural development. Some threats to bull trout are the continuing effects of past land management activities. Organization and Development of the Recovery Plan Because bull trout in the coterminous United States are widely distributed within a large area, the recovery plan is organized into multiple chapters. This introductory chapter (Chapter 1) describes our overall recovery strategy for the species, defines recovery, and identifies recovery actions applicable for all listed bull trout in the coterminous United States. Each successive chapter focuses on bull trout in specific geographic areas (recovery units), and describes conditions, defines recovery criteria, and identifies specific recovery actions for the recovery unit. Recovery Objectives The goal of this recovery plan is to describe the actions needed to achieve the recovery of bull trout, that is, to ensure the long-term persistence of self-sustaining, complex interacting groups (or multiple local populations that may have overlapping spawning and rearing areas) of bull trout distributed across the species' native range. Recovery of bull trout will require reducing threats to the long-term persistence of populations, maintaining multiple interconnected populations of bull trout across the diverse habitats of their native range, and preserving the diversity of bull trout life-history strategies (e.g., resident or migratory forms, emigration age, spawning frequency, local habitat adaptations). To recover bull trout, the following four objectives have been identified: ? Maintain current distribution of bull trout within core areas as described in recovery unit chapters and restore distribution where recommended in recovery unit chapters. ? Maintain stable or increasing trend in abundance of bull trout. ? Restore and maintain suitable habitat conditions for all bull trout life history stages and strategies. ? Conserve genetic diversity and provide opportunity for genetic exchange. ? These objectives apply to bull trout in all recovery units. Additional objectives may be necessary to achieve recovery in some recovery units and will be identified in the respective recovery unit chapters. Recovery Criteria Criteria are established to assess whether recovery objectives are being achieved. Criteria specific to each recovery unit are defined in each recovery unit chapter. Individual chapters may contain criteria for assessing the status of bull trout and alleviation of threats that are unique to one or several recovery units. However, every recovery unit chapter will contain criteria that address the following characteristics: ? The distribution of bull trout in identified and potential local populations in all core areas within the recovery unit. ? The estimated abundance of adult bull trout within core areas in the recovery unit, expressed as either a point estimate or a range of individuals. ? The presence of stable or increasing trends for adult bull trout abundance in the recovery unit. ? The restoration of passage at specific barriers identified as inhibiting recovery. We expect recovery of bull trout to be a dynamic process occurring over time. The recovery objectives are based on our current knowledge and may be refined as more information becomes available. Some local populations of bull trout, and possibly core area populations, may be extirpated even though recovery actions are being implemented. If reestablishment of recently extirpated populations is not feasible or practical, recovery criteria for a given recovery unit will be revised on a case-by-case basis. Meeting the four recovery criteria is not intended to be precluded where localized extirpations of bull trout are offset by sufficiently strong improvements in other areas of a recovery unit in meeting the four recovery objectives. The determination of whether a distinct population segment of bull trout is recovered will rely on an analysis of the overall status of the species, threats to the species, and the adequacy of existing regulatory and conservation mechanisms. For example, it may be possible for the Columbia River Distinct Population Segment, which has 22 recovery units, to be recovered prior to all recovery unit criteria being met in all recovery units. Success in accomplishing the recovery VI criteria will be reviewed and considered for the impacts both within a recovery unit and throughout a distinct population segment. Actions Needed Specific tasks falling within the following seven categories will be necessary to initiate recovery within all recovery units: ? Protect, restore, and maintain suitable habitat conditions for bull trout. ? Prevent and reduce negative effects of normative fishes and other normative taxa on bull trout. ? Establish fisheries management goals and objectives compatible with bull trout recovery and implement practices to achieve goals. ? Characterize, conserve, and monitor genetic diversity and gene flow among local populations of bull trout. ? Conduct research and monitoring to implement and evaluate bull trout recovery activities, consistent with an adaptive management approach using feedback from implemented, site-specific recovery tasks. ? Use all available conservation programs and regulations to protect and conserve bull trout and bull trout habitats. ? Assess the implementation of bull trout recovery by recovery units and revise recovery unit plans based on evaluations. Recovery Priority Number The recovery priority number for bull trout in the coterminous United States is 9C, on a scale of 1 to 18, indicating that (1) taxonomically, these populations are distinct population segments of a species, (2) the five populations are subject to a moderate degree of threat(s), (3) the recovery potential is high, and (4) the degree of potential conflict during recovery is high. vrr Estimated Cost of Recovery The total cost estimate of recovery for bull trout in the coterminous United States is presented in the individual recovery unit chapters. The costs presented in each chapter are attributed to bull trout conservation but other species will also benefit. Date of Recovery Expected time to achieve recovery varies among recovery units because of differences in bull trout status, factors affecting bull trout, implementation and effectiveness of recovery tasks, and responses to recovery tasks. Achieving bull trout recovery in all recovery units will be a complex process that will likely take 25 years or more. vin Close

• 1788. [Image] An examination of the Klamath Basin crisis : restructuring the discourse within an identity-based framework

  	Thesis (B.A.) -- Whitman College, 2002; Includes bibliographical references (leaves 79-83)
  	Citation × Citation Citation Abstract Copy Title: An examination of the Klamath Basin crisis : restructuring the discourse within an identity-based framework Author: Dornsife, Alison M. Year: 2002, 2005, 2004 Thesis (B.A.) -- Whitman College, 2002; Includes bibliographical references (leaves 79-83) Title: An examination of the Klamath Basin crisis : restructuring the discourse within an identity-based framework Author: Dornsife, Alison M. Year: 2002, 2005, 2004 Thesis (B.A.) -- Whitman College, 2002; Includes bibliographical references (leaves 79-83) Close

• 1789. [Image] Biofuels and internal combustion engine options for tour boats on Crater Lake

  	ill.; Thesis (M.S.M.E.)--University of Washington, 2000; Includes bibliographical references (p. 321-339)
  	Citation × Citation Citation Abstract Copy Title: Biofuels and internal combustion engine options for tour boats on Crater Lake Author: O'Keefe, Michael Patrick Year: 2000, 2009 ill.; Thesis (M.S.M.E.)--University of Washington, 2000; Includes bibliographical references (p. 321-339) Title: Biofuels and internal combustion engine options for tour boats on Crater Lake Author: O'Keefe, Michael Patrick Year: 2000, 2009 ill.; Thesis (M.S.M.E.)--University of Washington, 2000; Includes bibliographical references (p. 321-339) Close

• 1790. [Image] Klamath Falls Resource Area resource management plan and environmental impact statement : final : Volume 3

  	Proposed resource management plan/final environmental impact statement for the Klamath Falls Resource Area
  	Citation × Citation Citation Abstract Copy Title: Klamath Falls Resource Area resource management plan and environmental impact statement : final : Volume 3 Author: United States. Bureau of Land Management. Klamath Falls Resource Area Office Year: 1994, 2005 Proposed resource management plan/final environmental impact statement for the Klamath Falls Resource Area Title: Klamath Falls Resource Area resource management plan and environmental impact statement : final : Volume 3 Author: United States. Bureau of Land Management. Klamath Falls Resource Area Office Year: 1994, 2005 Proposed resource management plan/final environmental impact statement for the Klamath Falls Resource Area Close