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• 1521. [Article] Seasonal movement patterns and habitat use of westslope cutthroat trout in two headwater tributary streams of the John Day River

  Radiotelemetry was used to study the seasonal movements and habitat use of adult westslope cutthroat trout Oncorhynchus clarki lewisi in Roberts Creek and Rail Creek, headwater tributaries of the John ...

  Citation × Citation Citation Abstract Copy Title: Seasonal movement patterns and habitat use of westslope cutthroat trout in two headwater tributary streams of the John Day River Author: Starcevich, Steven J. Radiotelemetry was used to study the seasonal movements and habitat use of adult westslope cutthroat trout Oncorhynchus clarki lewisi in Roberts Creek and Rail Creek, headwater tributaries of the John Day River, Oregon, from September 2000 to December 2001. The objectives were to (1) describe adult cutthroat trout life history in headwater streams by comparing seasonal movement patterns, and (2) assess seasonal habitat selection by comparing habitat use to availability. For seasonal comparison, only fish that survived with an active transmitter throughout winter, spring, and summer were used in the analysis. Sample size was 17 (mean fork length, 241mm) on Roberts Creek and 9 (mean fork length, 252 mm) on Rail Creek. In winter and summer, radiotagged fish were relatively sedentary on both Roberts Creek (median home ranges, 35 and 104 m, respectively) and Rail Creek (median home ranges, 104 and 112 m). In spring, 65% of fish in both streams moved over 100 m upstream to spawn; upstream movements were as long as 1,138 m (median, 271 m) on Roberts Creek and as long as 3,771 m (median, 311 m) on Rail Creek. Postspawning movements downstream were common; 82% of fish on Roberts Creek and 57% on Rail Creek showed homing behavior, returning in summer to the same channel unit they inhabited in winter. Fish length was positively correlated to total movement distance in spring on Roberts Creek but not on Rail Creek. Over 86% of the surface area of both creeks consisted of fast-water channel units. Instream large wood created the majority of habitat heterogeneity in both streams and radiotagged cutthroat trout were strongly associated with large wood pools throughout the year. Plunge pools were positively selected throughout the year on both streams. Headwater-resident populations of cutthroat trout are often considered nonmigratory; however, these radiotagged fish showed fluvial migratory behavior. These results demonstrate that habitat heterogeneity and connectivity are important life history requirements for fluvial headwater resident cutthroat trout. Title: Seasonal movement patterns and habitat use of westslope cutthroat trout in two headwater tributary streams of the John Day River Author: Starcevich, Steven J. Radiotelemetry was used to study the seasonal movements and habitat use of adult westslope cutthroat trout Oncorhynchus clarki lewisi in Roberts Creek and Rail Creek, headwater tributaries of the John Day River, Oregon, from September 2000 to December 2001. The objectives were to (1) describe adult cutthroat trout life history in headwater streams by comparing seasonal movement patterns, and (2) assess seasonal habitat selection by comparing habitat use to availability. For seasonal comparison, only fish that survived with an active transmitter throughout winter, spring, and summer were used in the analysis. Sample size was 17 (mean fork length, 241mm) on Roberts Creek and 9 (mean fork length, 252 mm) on Rail Creek. In winter and summer, radiotagged fish were relatively sedentary on both Roberts Creek (median home ranges, 35 and 104 m, respectively) and Rail Creek (median home ranges, 104 and 112 m). In spring, 65% of fish in both streams moved over 100 m upstream to spawn; upstream movements were as long as 1,138 m (median, 271 m) on Roberts Creek and as long as 3,771 m (median, 311 m) on Rail Creek. Postspawning movements downstream were common; 82% of fish on Roberts Creek and 57% on Rail Creek showed homing behavior, returning in summer to the same channel unit they inhabited in winter. Fish length was positively correlated to total movement distance in spring on Roberts Creek but not on Rail Creek. Over 86% of the surface area of both creeks consisted of fast-water channel units. Instream large wood created the majority of habitat heterogeneity in both streams and radiotagged cutthroat trout were strongly associated with large wood pools throughout the year. Plunge pools were positively selected throughout the year on both streams. Headwater-resident populations of cutthroat trout are often considered nonmigratory; however, these radiotagged fish showed fluvial migratory behavior. These results demonstrate that habitat heterogeneity and connectivity are important life history requirements for fluvial headwater resident cutthroat trout. Close

• 1522. [Article] Population dynamics of selected zooplankton in three oligotrophic Oregon lakes

  Selected zooplankton from three oligotrophic lakes in Oregon were studied to determine whether or not their instantaneous birth rates and densities could be used in lake classification. The species of ...

  Citation × Citation Citation Abstract Copy Title: Population dynamics of selected zooplankton in three oligotrophic Oregon lakes Author: Malick, James G. Selected zooplankton from three oligotrophic lakes in Oregon were studied to determine whether or not their instantaneous birth rates and densities could be used in lake classification. The species of zooplankton studied in their respective lakes were Daphnia, pulex in Crater Lake, Daphnia longispina in Odell Lake, and Daphnia longispina and Diaphanosoma brachyurum in Woahink Lake. Instantaneous birth rates, densities and other population parameters were estimated for these species. The species studied in Odell and Woahink Lakes were also collected to determine the relationship between diel vertical distribution of these species and the temperature and phytoplankton primary production occurring in the lakes, Woahink Lake Daphnia had the highest instantaneous birth rates for Daphnia sp. of the three lakes. However, Woahink Lake Daphnia carried fewer eggs and were less dense than Daphnia in Odell Lake on every sampling date. Crater Lake Daphnia were usually less dense and had lower instantaneous birth rates than was observed for the Woahink Lake Daphnia. Because of changes in the density of zooplankters from one year to the next, as occurred with Daphnia in Crater Lake, and the lack of correlation between phytoplankton primary production and density, as occurred for Daphnia and Diaphanosoma in Woahink Lake, application of these population dynamics to lake systematics were nullified. The finite birth rate also lacked the expected correlation with phytoplankton primary production for all the selected species in the study lakes. The lack of correlation may be due to interactions between the total species of zooplankton present in the lakes. If instantaneous birth rate and density were calculated for all the species in each lake it might be possible to use them for lake classification. However, the time expended in analysis would be prohibitive. The did vertical distribution of Daphnia in Odell. Lake showed a typical migration to the surface at night and a return to deeper water during daylight hours. In Woahink Lake, however, Daphnia and Diaphanosoma were found to migrate only when the lake reached temperatures near 15°C or greater. The phytoplankton primary production occurring during the periods when migration did not take place, was equal to or greater than that occurring during some of the periods when vertical migration did occur. These observations may or may not have significance since the density of these two species did not show correlation with primary production. Title: Population dynamics of selected zooplankton in three oligotrophic Oregon lakes Author: Malick, James G. Selected zooplankton from three oligotrophic lakes in Oregon were studied to determine whether or not their instantaneous birth rates and densities could be used in lake classification. The species of zooplankton studied in their respective lakes were Daphnia, pulex in Crater Lake, Daphnia longispina in Odell Lake, and Daphnia longispina and Diaphanosoma brachyurum in Woahink Lake. Instantaneous birth rates, densities and other population parameters were estimated for these species. The species studied in Odell and Woahink Lakes were also collected to determine the relationship between diel vertical distribution of these species and the temperature and phytoplankton primary production occurring in the lakes, Woahink Lake Daphnia had the highest instantaneous birth rates for Daphnia sp. of the three lakes. However, Woahink Lake Daphnia carried fewer eggs and were less dense than Daphnia in Odell Lake on every sampling date. Crater Lake Daphnia were usually less dense and had lower instantaneous birth rates than was observed for the Woahink Lake Daphnia. Because of changes in the density of zooplankters from one year to the next, as occurred with Daphnia in Crater Lake, and the lack of correlation between phytoplankton primary production and density, as occurred for Daphnia and Diaphanosoma in Woahink Lake, application of these population dynamics to lake systematics were nullified. The finite birth rate also lacked the expected correlation with phytoplankton primary production for all the selected species in the study lakes. The lack of correlation may be due to interactions between the total species of zooplankton present in the lakes. If instantaneous birth rate and density were calculated for all the species in each lake it might be possible to use them for lake classification. However, the time expended in analysis would be prohibitive. The did vertical distribution of Daphnia in Odell. Lake showed a typical migration to the surface at night and a return to deeper water during daylight hours. In Woahink Lake, however, Daphnia and Diaphanosoma were found to migrate only when the lake reached temperatures near 15°C or greater. The phytoplankton primary production occurring during the periods when migration did not take place, was equal to or greater than that occurring during some of the periods when vertical migration did occur. These observations may or may not have significance since the density of these two species did not show correlation with primary production. Close

• 1523. [Article] Development of materials and devices for separation of polyamido[a]mine dendrimers

  Over the last decade, the use of highly branched macromolecules, called dendrimers, is emerging. Polyamidoamine (PAMAM) dendrimers, in particular, have attracted high interest due to their unique properties, ...

  Citation × Citation Citation Abstract Copy Title: Development of materials and devices for separation of polyamido[a]mine dendrimers Author: Tennico, Yolanda H. Over the last decade, the use of highly branched macromolecules, called dendrimers, is emerging. Polyamidoamine (PAMAM) dendrimers, in particular, have attracted high interest due to their unique properties, such as well-defined size, shape, and solubility in water. Our group, as part of an interdisciplinary team, is currently working on developing a nanoextraction technology for high-yield dendrimer syntheses. Impurities may occur during the synthesis of these dendrimers, and therefore, to achieve higher purity products, chromatographic separations of dendrimers are an important part toward this goal. This thesis describes approaches toward this objective, focusing in two areas: at first, development of materials and devices that will enable separations of dendrimers in confines of capillary and chromatographic columns, and second, evaluation of the feasibility of transferring the separation techniques previously developed to the channels of microfluidic devices. The results showed that PAMAM dendrimers of various generations were successfully analyzed using capillary zone electrophoresis (CZE), capillary electrochromatography (CEC), and high-performance liquid chromatography (HPLC). Both CZE and HPLC have allowed for fast generational separations up to the fifth generation. Moreover, CZE can also assess the homogeneity and presence of side products in the synthesized dendrimers. RP-HPLC, on the other hand, allowed for separations of dendrimers with terminal amino and carboxyl groups. PAMAM dendrimers can also be used as template molecules to prepare monolithic capillary columns for liquid chromatography and capillary electrochromatography. This method has provided two advantages: 1) dendrimers can be used as template molecules for controlling pore structures, 2) selective sorbents can be produced with surface sites that are complementary in chemical functionality to the dendrimer template molecule. These highly selective sorbents were able to provide separation of dendrimers from various generations, particularly of high generations, in the CEC mode. As the first step toward the development of a nanoextraction technology for high yield dendrimer syntheses, the feasibility of extending the separation techniques developed on-column into channels of a microfluidic chip was examined. In this study, electrophoresis was employed to separate different generations of dendrimers in glass microfluidic chips using laser-induced fluorescence detection. The use of microfluidic system for dendrimer application offers great potential due to its rapid analysis times, small sample volume requirements, and the ability to integrate several steps of analyses in one chip. Title: Development of materials and devices for separation of polyamido[a]mine dendrimers Author: Tennico, Yolanda H. Over the last decade, the use of highly branched macromolecules, called dendrimers, is emerging. Polyamidoamine (PAMAM) dendrimers, in particular, have attracted high interest due to their unique properties, such as well-defined size, shape, and solubility in water. Our group, as part of an interdisciplinary team, is currently working on developing a nanoextraction technology for high-yield dendrimer syntheses. Impurities may occur during the synthesis of these dendrimers, and therefore, to achieve higher purity products, chromatographic separations of dendrimers are an important part toward this goal. This thesis describes approaches toward this objective, focusing in two areas: at first, development of materials and devices that will enable separations of dendrimers in confines of capillary and chromatographic columns, and second, evaluation of the feasibility of transferring the separation techniques previously developed to the channels of microfluidic devices. The results showed that PAMAM dendrimers of various generations were successfully analyzed using capillary zone electrophoresis (CZE), capillary electrochromatography (CEC), and high-performance liquid chromatography (HPLC). Both CZE and HPLC have allowed for fast generational separations up to the fifth generation. Moreover, CZE can also assess the homogeneity and presence of side products in the synthesized dendrimers. RP-HPLC, on the other hand, allowed for separations of dendrimers with terminal amino and carboxyl groups. PAMAM dendrimers can also be used as template molecules to prepare monolithic capillary columns for liquid chromatography and capillary electrochromatography. This method has provided two advantages: 1) dendrimers can be used as template molecules for controlling pore structures, 2) selective sorbents can be produced with surface sites that are complementary in chemical functionality to the dendrimer template molecule. These highly selective sorbents were able to provide separation of dendrimers from various generations, particularly of high generations, in the CEC mode. As the first step toward the development of a nanoextraction technology for high yield dendrimer syntheses, the feasibility of extending the separation techniques developed on-column into channels of a microfluidic chip was examined. In this study, electrophoresis was employed to separate different generations of dendrimers in glass microfluidic chips using laser-induced fluorescence detection. The use of microfluidic system for dendrimer application offers great potential due to its rapid analysis times, small sample volume requirements, and the ability to integrate several steps of analyses in one chip. Close

• 1524. [Article] Long term albacore (Thunnus alalunga) spatio-temporal association with environmental variability in the Northeastern Pacific

  This study investigated long-term (1961-2008) changes in albacore (Thunnus alalunga) abundance and distribution in relation to local environmental and large-scale climate indices in the Northeastern Pacific ...

  Citation × Citation Citation Abstract Copy Title: Long term albacore (Thunnus alalunga) spatio-temporal association with environmental variability in the Northeastern Pacific Author: Phillips, A. Jason This study investigated long-term (1961-2008) changes in albacore (Thunnus alalunga) abundance and distribution in relation to local environmental and large-scale climate indices in the Northeastern Pacific using time series and spatial analyses. Prior to the time series analysis, a wavelet analysis was conducted to examine nonrandom patterns of cyclical variability which revealed that monthly and annual time scales had the highest non-random variability. Thus, the time series analysis was done at these two scales using non-linear generalized additive models (GAMs) and threshold GAMs. At the monthly scale, sea surface temperature (SST) was found to be the variable with the strongest (positive) association to albacore catch per unit effort (CPUE). This association was likely driven by the seasonal migrations of juvenile albacore into and out of the U.S. coastal waters. At the yearly time scale over large geographical areas, the SST association broke down, and the scalar wind speed cubed (an indicator of mixed layer depth) at a five year lag became the dominant variable. The scalar wind speed cubed index explained 65% of the variability and was highly significant, even after adjusting for multiple tests (Bonferroni corrected P-value<0.001). These results suggest that a deeper mixed layer in the Northeastern Pacific may provide favorable foraging habitat for juvenile (mostly age 3) albacore, resulting in successful growth, spawning, and recruitment into the fishery in later years. This mixed layer depth association could help managers and stock assessment groups in their efforts to integrate environmental factors into the estimate of albacore population size. The spatial/spatio-temporal analyses involved modeling the CPUE with four competing GAM formulations, each representative of a different hypotheses for albacore distribution: 1) spatial, 2) spatial and environmental (SST, PDO, and MEI), 3) spatially variant, and 4) nonstationary, as indicated by the North Pacific regime shift of 1977. Results indicate that SST had a predominantly positive but spatially-variable effect on albacore CPUE, while the PDO had a negative overall effect. Specifically, CPUE was found to increase with increased SST, particularly off of Oregon and Washington. These results imply that if ocean temperatures continue to increase, west coast communities reliant on commercial albacore fisheries are likely to be negatively impacted in the southern areas but positively benefited in the northern areas, where current albacore landings are highest. Title: Long term albacore (Thunnus alalunga) spatio-temporal association with environmental variability in the Northeastern Pacific Author: Phillips, A. Jason This study investigated long-term (1961-2008) changes in albacore (Thunnus alalunga) abundance and distribution in relation to local environmental and large-scale climate indices in the Northeastern Pacific using time series and spatial analyses. Prior to the time series analysis, a wavelet analysis was conducted to examine nonrandom patterns of cyclical variability which revealed that monthly and annual time scales had the highest non-random variability. Thus, the time series analysis was done at these two scales using non-linear generalized additive models (GAMs) and threshold GAMs. At the monthly scale, sea surface temperature (SST) was found to be the variable with the strongest (positive) association to albacore catch per unit effort (CPUE). This association was likely driven by the seasonal migrations of juvenile albacore into and out of the U.S. coastal waters. At the yearly time scale over large geographical areas, the SST association broke down, and the scalar wind speed cubed (an indicator of mixed layer depth) at a five year lag became the dominant variable. The scalar wind speed cubed index explained 65% of the variability and was highly significant, even after adjusting for multiple tests (Bonferroni corrected P-value<0.001). These results suggest that a deeper mixed layer in the Northeastern Pacific may provide favorable foraging habitat for juvenile (mostly age 3) albacore, resulting in successful growth, spawning, and recruitment into the fishery in later years. This mixed layer depth association could help managers and stock assessment groups in their efforts to integrate environmental factors into the estimate of albacore population size. The spatial/spatio-temporal analyses involved modeling the CPUE with four competing GAM formulations, each representative of a different hypotheses for albacore distribution: 1) spatial, 2) spatial and environmental (SST, PDO, and MEI), 3) spatially variant, and 4) nonstationary, as indicated by the North Pacific regime shift of 1977. Results indicate that SST had a predominantly positive but spatially-variable effect on albacore CPUE, while the PDO had a negative overall effect. Specifically, CPUE was found to increase with increased SST, particularly off of Oregon and Washington. These results imply that if ocean temperatures continue to increase, west coast communities reliant on commercial albacore fisheries are likely to be negatively impacted in the southern areas but positively benefited in the northern areas, where current albacore landings are highest. Close

• 1525. [Article] Factors affecting development of iris rhizome rot caused by Botrytis convoluta Whetzel and Drayton

  Abundant conidial and sclerotial production occurs on iris plants infected with Botrytis convoluta Whetzel and Drayton during the cool moist months of the year. Experiments were designed to study the survival ...

  Citation × Citation Citation Abstract Copy Title: Factors affecting development of iris rhizome rot caused by Botrytis convoluta Whetzel and Drayton Author: Maas, J. L. Abundant conidial and sclerotial production occurs on iris plants infected with Botrytis convoluta Whetzel and Drayton during the cool moist months of the year. Experiments were designed to study the survival and inoculum potential of conidia and sclerotia. Basic nutritional requirements of the fungus in culture were also studied. Results of field and laboratory studies indicated a large percentage of iris plants apparently free of B. convoluta carried latent infections. The evidence indicates that these latent infections originate from contact of healthy tissue with senescent or dead leaf and/ or rhizome tissues. Progression into healthy tissues is halted by increasingly higher soil and air temperatures and periderm formation which walls off the infections. Active rot development occurs when conditions favorable for pathogenesis return. These latent infections which are undetectable visually would be a very important means of dissemination of the disease since growers believe they are shipping sound rhizomes. Chemical control would be difficult because the infections are inaccessible to non-systemic fungicides. Field inoculation of rhizomes with conidia, sclerotia and rolled-oat cultures of B. convoluta resulted in significantly increased infection of iris plants inoculated with conidia. Sclerotia placed onto wounded areas of rhizomes also caused significantly increased infection incidence. Differences in field resistance to the pathogen were also noted. Iris plants of the variety Cotlet were found generally more prone to infection and more extensively rotted than Apricot Glory and Sunset Blaze varieties. Laboratory results indicated that conidia and sclerotia were able to cause infection of intact iris rhizome offsets. Conidia applied to offsets colonized senescent leaves and, using this as a food base, invaded healthy juvenile leaves in contact with them. Germ tubes were observed lying parallel to and over longitudinal leaf epidermal cell wall junctures and in several instances, they appeared to be between cells. Terminal appressorium-like swellings of germ tubes were observed on leaf surfaces; however, no direct penetration of leaf tissue was observed. Sclerotia remained viable for one year at 5 to 25°C under dry storage conditions. Survival of conidia stored in situ on colonies for 257 days decreased with increasingly higher temperatures, dropping to less than five percent at 25°C after 210 days. Survival of sclerotia or conidia was not markedly affected by storage at -70°C for 90 days, and conidia remained at least 70 percent viable at -70°C after 257 days. Sclerotia survived in moist soil for 60 days at temperatures of 15°C or below. No sclerotia were found viable after 60 days when soil temperatures were above 20°C. Non-viable sclerotia were found to be colonized by other fungi; mainly species of Trichoderma, Fusarium, Mucor, and Sepedonium as well as by bacteria. Nutritional studies in vitro showed B. convoluta to utilize the carbohydrates maltose, glucose, sucrose, starch, galactose, and fructose, from good to poor carbon sources respectively. Lactose and sorbose were poor carbon sources. Nitrogen sources, from good to poor, were casein hydrolysate, asparagine, ammonium tartrate, ammonium sulfate, and glutamate. Potassium nitrate, glycine, and urea were poor nitrogen sources. Growth was most rapid when the pH of the media was pH 3-4. B. convoluta required light to be stimulated into sporulation. Sporulation was stimulated by exposure to white or to near-ultraviolet light. Optimum temperatures for linear growth was near 23°C and optimum for sclerotium formation was 10-15°C. Germination of conidia incubated in distilled water was generally very low (less than 10%) and germination was invariably much higher (85-100%) when an exogenous carbon source was supplied. Title: Factors affecting development of iris rhizome rot caused by Botrytis convoluta Whetzel and Drayton Author: Maas, J. L. Abundant conidial and sclerotial production occurs on iris plants infected with Botrytis convoluta Whetzel and Drayton during the cool moist months of the year. Experiments were designed to study the survival and inoculum potential of conidia and sclerotia. Basic nutritional requirements of the fungus in culture were also studied. Results of field and laboratory studies indicated a large percentage of iris plants apparently free of B. convoluta carried latent infections. The evidence indicates that these latent infections originate from contact of healthy tissue with senescent or dead leaf and/ or rhizome tissues. Progression into healthy tissues is halted by increasingly higher soil and air temperatures and periderm formation which walls off the infections. Active rot development occurs when conditions favorable for pathogenesis return. These latent infections which are undetectable visually would be a very important means of dissemination of the disease since growers believe they are shipping sound rhizomes. Chemical control would be difficult because the infections are inaccessible to non-systemic fungicides. Field inoculation of rhizomes with conidia, sclerotia and rolled-oat cultures of B. convoluta resulted in significantly increased infection of iris plants inoculated with conidia. Sclerotia placed onto wounded areas of rhizomes also caused significantly increased infection incidence. Differences in field resistance to the pathogen were also noted. Iris plants of the variety Cotlet were found generally more prone to infection and more extensively rotted than Apricot Glory and Sunset Blaze varieties. Laboratory results indicated that conidia and sclerotia were able to cause infection of intact iris rhizome offsets. Conidia applied to offsets colonized senescent leaves and, using this as a food base, invaded healthy juvenile leaves in contact with them. Germ tubes were observed lying parallel to and over longitudinal leaf epidermal cell wall junctures and in several instances, they appeared to be between cells. Terminal appressorium-like swellings of germ tubes were observed on leaf surfaces; however, no direct penetration of leaf tissue was observed. Sclerotia remained viable for one year at 5 to 25°C under dry storage conditions. Survival of conidia stored in situ on colonies for 257 days decreased with increasingly higher temperatures, dropping to less than five percent at 25°C after 210 days. Survival of sclerotia or conidia was not markedly affected by storage at -70°C for 90 days, and conidia remained at least 70 percent viable at -70°C after 257 days. Sclerotia survived in moist soil for 60 days at temperatures of 15°C or below. No sclerotia were found viable after 60 days when soil temperatures were above 20°C. Non-viable sclerotia were found to be colonized by other fungi; mainly species of Trichoderma, Fusarium, Mucor, and Sepedonium as well as by bacteria. Nutritional studies in vitro showed B. convoluta to utilize the carbohydrates maltose, glucose, sucrose, starch, galactose, and fructose, from good to poor carbon sources respectively. Lactose and sorbose were poor carbon sources. Nitrogen sources, from good to poor, were casein hydrolysate, asparagine, ammonium tartrate, ammonium sulfate, and glutamate. Potassium nitrate, glycine, and urea were poor nitrogen sources. Growth was most rapid when the pH of the media was pH 3-4. B. convoluta required light to be stimulated into sporulation. Sporulation was stimulated by exposure to white or to near-ultraviolet light. Optimum temperatures for linear growth was near 23°C and optimum for sclerotium formation was 10-15°C. Germination of conidia incubated in distilled water was generally very low (less than 10%) and germination was invariably much higher (85-100%) when an exogenous carbon source was supplied. Close

• 1526. [Article] Zooplankton of the Galapagos Islands

  The marine climate of the Galapagos is spatially and seasonally heterogeneous. A taxonomically comprehensive study of Galapagos zooplankton has never been done. This study is an initial effort to establish ...

  Citation × Citation Citation Abstract Copy Title: Zooplankton of the Galapagos Islands Author: Figueroa, Diego The marine climate of the Galapagos is spatially and seasonally heterogeneous. A taxonomically comprehensive study of Galapagos zooplankton has never been done. This study is an initial effort to establish the distribution and community structure of zooplankton in the Archipelago. I collected zooplankton samples by vertical tows over the Galapagos shelf during the islands’ cold and warm seasons. Abundance was determined and copepods and euphausiids were identified to species. Hydrographic, nutrient and chlorophyll profiles were obtained for some sites. Non-metric Multidimensional Scaling (NMS) ordinations, Multi-Response Permutation Procedures (MRPP) and Indicator Species Analyses (ISA) were used to determine trends in community composition. Two marine systems were identified: 1) a nutrient-rich upwelling system with a shallow mixed layer and a diatom dominated phytoplankton community in the west and 2) a non-upwelling system with a deeper mixed layer, lower surface nutrient concentrations and a phytoplankton community dominated by small cells in the east. During the cold season three distinct zooplankton communities were observed that divide into western, central, and southeastern regions. During the warm season, the community in the west was replaced by a mix of species from the central region and abundance decreased. The diverse zooplankton community with varying geographical and seasonal affinities reflects the advective sources of surrounding waters. In addition to diverse oceanic environments, the Galapagos also have a unique set of inland pools known as anchialine habitats. I collected zooplankton from various anchialine pools in three different islands. These pools contain species of specialized cave-dwellers including undescribed species of Ridgewayia and Pseudocyclops (calanoid copepods). I describe these species and apply morphological and molecular methods to determine phylogenetic relationships and patterns of colonization. The mitochondrial gene cytochrome c oxidase subunit I (COI) and the nuclear internal transcribed spacer 1 (ITS1) were used for phylogenetic analyses. The ITS1gene successfully reconstructed phylogenies, but the COI gene was highly conserved across these two families. This gene may not be appropriate as the current standard for “bar-coding” all marine species. These anchialine copepods are a result of several independent colonization events with phylogenetic ties to extant species in the western Pacific and Caribbean. Title: Zooplankton of the Galapagos Islands Author: Figueroa, Diego The marine climate of the Galapagos is spatially and seasonally heterogeneous. A taxonomically comprehensive study of Galapagos zooplankton has never been done. This study is an initial effort to establish the distribution and community structure of zooplankton in the Archipelago. I collected zooplankton samples by vertical tows over the Galapagos shelf during the islands’ cold and warm seasons. Abundance was determined and copepods and euphausiids were identified to species. Hydrographic, nutrient and chlorophyll profiles were obtained for some sites. Non-metric Multidimensional Scaling (NMS) ordinations, Multi-Response Permutation Procedures (MRPP) and Indicator Species Analyses (ISA) were used to determine trends in community composition. Two marine systems were identified: 1) a nutrient-rich upwelling system with a shallow mixed layer and a diatom dominated phytoplankton community in the west and 2) a non-upwelling system with a deeper mixed layer, lower surface nutrient concentrations and a phytoplankton community dominated by small cells in the east. During the cold season three distinct zooplankton communities were observed that divide into western, central, and southeastern regions. During the warm season, the community in the west was replaced by a mix of species from the central region and abundance decreased. The diverse zooplankton community with varying geographical and seasonal affinities reflects the advective sources of surrounding waters. In addition to diverse oceanic environments, the Galapagos also have a unique set of inland pools known as anchialine habitats. I collected zooplankton from various anchialine pools in three different islands. These pools contain species of specialized cave-dwellers including undescribed species of Ridgewayia and Pseudocyclops (calanoid copepods). I describe these species and apply morphological and molecular methods to determine phylogenetic relationships and patterns of colonization. The mitochondrial gene cytochrome c oxidase subunit I (COI) and the nuclear internal transcribed spacer 1 (ITS1) were used for phylogenetic analyses. The ITS1gene successfully reconstructed phylogenies, but the COI gene was highly conserved across these two families. This gene may not be appropriate as the current standard for “bar-coding” all marine species. These anchialine copepods are a result of several independent colonization events with phylogenetic ties to extant species in the western Pacific and Caribbean. Close

• 1527. [Article] Mapping and lithologic interpretation of the Territorial Sea, Oregon

  Seafloor lithologic maps have been widely used to identify conservation sites. In this study, a lithologic interpretation of Oregon's territorial seafloor was created as an interim product in response ...

  Citation × Citation Citation Abstract Copy Title: Mapping and lithologic interpretation of the Territorial Sea, Oregon Author: Agapito, Melinda T. Seafloor lithologic maps have been widely used to identify conservation sites. In this study, a lithologic interpretation of Oregon's territorial seafloor was created as an interim product in response to the need for a comprehensive lithologic map that will be used in the identification, evaluation and design of marine reserves in Oregon. While future multibeam mapping of the Oregon Territorial Sea will likely replace this product in the next few years, the ground truth data from which the map is constructed will continue in use in future efforts. This mapping project utilized a classical geologic approach aided by GIS technology in which all relevant thematic geologic layers were applied to interpret patterns of seafloor lithology. The discovery of approximately 9,600 NOS bottom samples from the National Ocean Service (NOS) historic hydrographic smooth sheet archives has tremendously improved upon the original sample dataset (305 bottom samples) used in previous characterization of Oregon's territorial seabed. Supplementing the NOS bottom samples, other existing datasets including historic kelp distribution (used as proxy for rock), a triangulated irregular network (TIN) surface model derived from bathymetric soundings, rock outcrops digitized from 0.5 meter aerial photos, subsurface structure, and the adjacent onshore Oregon digital geologic map were used. While the collection of smooth sheet data from historic surveys utilized leadline sampling techniques and traditional navigation methods such as three-point sextant positioning, it was observed that the typical positional error averaged ~28 meters relative to contemporary aerial photography where comparison was possible. GIS software was used for simultaneous display of varied thematic layers, qualitative interpretation, quantitative accuracy assessment, and density mapping processes in this project. This current mapping effort showed that the NOS "smooth sheet" data collected from 1858 to 1958 compares well with modern data and that the NOS datasets and methods are able to capture the general outlines of rocky outcrops particularly in shallow areas. The territorial lithologic map shows a reasonable overall accuracy of 64 % relative to existing habitat interpretation of rocky reefs based on high-resolution multibeam data. Furthermore, the NOS bottom samples provide an opportunity to map additional sediment types that are not represented in the existing Surficial Geologic Habitat (SGH) map of the territorial sea. Finally, a companion product to the maps, a composite density map was created from the underlying datasets (kelp, bathymetry and bottom samples) to represent the spatial variation in data quality and quantity used in the interpretation of seafloor lithology. It is anticipated that the data obtained from this study will serve as a useful tool for scientific investigation and management efforts such as the ocean zoning in the nearshore region of the Oregon coast, which includes the upcoming designation and evaluation of marine reserves. Title: Mapping and lithologic interpretation of the Territorial Sea, Oregon Author: Agapito, Melinda T. Seafloor lithologic maps have been widely used to identify conservation sites. In this study, a lithologic interpretation of Oregon's territorial seafloor was created as an interim product in response to the need for a comprehensive lithologic map that will be used in the identification, evaluation and design of marine reserves in Oregon. While future multibeam mapping of the Oregon Territorial Sea will likely replace this product in the next few years, the ground truth data from which the map is constructed will continue in use in future efforts. This mapping project utilized a classical geologic approach aided by GIS technology in which all relevant thematic geologic layers were applied to interpret patterns of seafloor lithology. The discovery of approximately 9,600 NOS bottom samples from the National Ocean Service (NOS) historic hydrographic smooth sheet archives has tremendously improved upon the original sample dataset (305 bottom samples) used in previous characterization of Oregon's territorial seabed. Supplementing the NOS bottom samples, other existing datasets including historic kelp distribution (used as proxy for rock), a triangulated irregular network (TIN) surface model derived from bathymetric soundings, rock outcrops digitized from 0.5 meter aerial photos, subsurface structure, and the adjacent onshore Oregon digital geologic map were used. While the collection of smooth sheet data from historic surveys utilized leadline sampling techniques and traditional navigation methods such as three-point sextant positioning, it was observed that the typical positional error averaged ~28 meters relative to contemporary aerial photography where comparison was possible. GIS software was used for simultaneous display of varied thematic layers, qualitative interpretation, quantitative accuracy assessment, and density mapping processes in this project. This current mapping effort showed that the NOS "smooth sheet" data collected from 1858 to 1958 compares well with modern data and that the NOS datasets and methods are able to capture the general outlines of rocky outcrops particularly in shallow areas. The territorial lithologic map shows a reasonable overall accuracy of 64 % relative to existing habitat interpretation of rocky reefs based on high-resolution multibeam data. Furthermore, the NOS bottom samples provide an opportunity to map additional sediment types that are not represented in the existing Surficial Geologic Habitat (SGH) map of the territorial sea. Finally, a companion product to the maps, a composite density map was created from the underlying datasets (kelp, bathymetry and bottom samples) to represent the spatial variation in data quality and quantity used in the interpretation of seafloor lithology. It is anticipated that the data obtained from this study will serve as a useful tool for scientific investigation and management efforts such as the ocean zoning in the nearshore region of the Oregon coast, which includes the upcoming designation and evaluation of marine reserves. Close

• 1528. [Article] Coastal ocean response to alongshore variations in topography and wind forcing

  The effects of alongshore variability in topography (banks and capes) and spatial variability in the wind forcing, including the wind-stress curl, on coastal ocean circulation are studied using a combination ...

  Citation × Citation Citation Abstract Copy Title: Coastal ocean response to alongshore variations in topography and wind forcing Author: Castelao, Renato Menezes The effects of alongshore variability in topography (banks and capes) and spatial variability in the wind forcing, including the wind-stress curl, on coastal ocean circulation are studied using a combination of observations and model simulations. Satellite sea surface temperature observations are used to describe the seasonal evolution of temperature fronts in the California Current System. The evolution is consistent with the seasonal cycle of wind forcing, but also reveals the profound influence of major capes in creating convoluted and offshore-diverted fronts. Although the greatest offshore excursion of fronts is found south of Cape Blanco, observations suggest that late in the upwelling season, the upwelling front (and jet) leaves the shelf to the north of the Cape, around Heceta Bank. This is supported by in situ observations obtained during the Coastal Ocean Advances in Shelf Transport (COAST) project, which depicted jet separation at Heceta Bank's downstream asymmetry with an average off-shelf transport around 0.7 Sv. Simulations exploring a large range in parameter space show that jet separation is expected to occur when the flow is strong (high Rossby number) and when the Burger number (the ratio of the squares of the internal Rossby radius of deformation and curvature of the topography) is close to one. Observations reveal that conditions at Heceta Bank during spring and summer are often nearly ideal for separation. The importance of the wind-stress curl to coastal circulation is also investigated. A region of upwelling-favorable wind-stress curl close to the coast downstream of a cape is shown to create a strong offshore intensification of the alongshore velocities, which helps jet separation via continuity and by creating potential vorticity contours that track far offshore of the cape. Stronger upwelling-favorable curl leads to earlier separation, while increasing the offshore extend of the region of strong curl leads to more separation. Finally, satellite scatterometer observations are used to show that the wind-stress curl is strongly enhanced around Cabo Frio, Brazil, during summer. At that time, curl-driven upwelling is as strong as coastal upwelling, which helps explain the observation that the coldest water along the coast is found near Cabo Frio. Title: Coastal ocean response to alongshore variations in topography and wind forcing Author: Castelao, Renato Menezes The effects of alongshore variability in topography (banks and capes) and spatial variability in the wind forcing, including the wind-stress curl, on coastal ocean circulation are studied using a combination of observations and model simulations. Satellite sea surface temperature observations are used to describe the seasonal evolution of temperature fronts in the California Current System. The evolution is consistent with the seasonal cycle of wind forcing, but also reveals the profound influence of major capes in creating convoluted and offshore-diverted fronts. Although the greatest offshore excursion of fronts is found south of Cape Blanco, observations suggest that late in the upwelling season, the upwelling front (and jet) leaves the shelf to the north of the Cape, around Heceta Bank. This is supported by in situ observations obtained during the Coastal Ocean Advances in Shelf Transport (COAST) project, which depicted jet separation at Heceta Bank's downstream asymmetry with an average off-shelf transport around 0.7 Sv. Simulations exploring a large range in parameter space show that jet separation is expected to occur when the flow is strong (high Rossby number) and when the Burger number (the ratio of the squares of the internal Rossby radius of deformation and curvature of the topography) is close to one. Observations reveal that conditions at Heceta Bank during spring and summer are often nearly ideal for separation. The importance of the wind-stress curl to coastal circulation is also investigated. A region of upwelling-favorable wind-stress curl close to the coast downstream of a cape is shown to create a strong offshore intensification of the alongshore velocities, which helps jet separation via continuity and by creating potential vorticity contours that track far offshore of the cape. Stronger upwelling-favorable curl leads to earlier separation, while increasing the offshore extend of the region of strong curl leads to more separation. Finally, satellite scatterometer observations are used to show that the wind-stress curl is strongly enhanced around Cabo Frio, Brazil, during summer. At that time, curl-driven upwelling is as strong as coastal upwelling, which helps explain the observation that the coldest water along the coast is found near Cabo Frio. Close

• 1529. [Article] On the optimization of performance in fractal-like branching microchannel heat transfer devices

  Fractal-like branching microchannel flow networks have been found to improve wall temperature uniformity and decrease both pressure drop and flow power compared to arrays of straight microchannels. The ...

  Citation × Citation Citation Abstract Copy Title: On the optimization of performance in fractal-like branching microchannel heat transfer devices Author: Heymann, Douglas Benjamin Fractal-like branching microchannel flow networks have been found to improve wall temperature uniformity and decrease both pressure drop and flow power compared to arrays of straight microchannels. The present study seeks to maximize the benefits of fractal-like branching channels by means of a gradient-based optimization algorithm. The algorithm identifies the geometric parameters that yield the highest ratio of benefit to cost; the benefit being the heat transfer with cost being flow power. The stream-wise pressure and wall temperature distributions were determined numerically using one-dimensional models validated using experimental diagnostics and computational flow analyses. Pressure distributions were used to assess flow power, and wall temperature was used as an optimization constraint. Several geometric constraints were imposed during optimization to ensure sufficient bonding area for fabrication, to maximize convective surface area and to prevent channel overlap. Three fractal-like devices were studied and optimized: a single-phase heat sink, a two-phase heat sink and a single-phase oil-to-water heat exchanger. The flow rate of the three devices was constrained using a maximum wall temperature constraint for the single-phase heat sink, the critical heat flux for the two-phase heat sink, and a fixed cold side mass flow rate and temperature rise in the case of the heat exchanger. The optimized solutions were found to depend highly on both the geometric and flow constraints imposed. As the terminal channel width was reduced, flow power was reduced in both single-phase and two-phase heat sinks. However, the flow power was increased in the heat exchanger due to the constrained volumetric flow rate. In addition, results show that if a maximum wall temperature constraint is employed, single-phase flow outperforms two-phase flow in terms of reduction in flow power. However when constrained by a critical heat flux, two-phase networks outperform single-phase networks by up to 150% Title: On the optimization of performance in fractal-like branching microchannel heat transfer devices Author: Heymann, Douglas Benjamin Fractal-like branching microchannel flow networks have been found to improve wall temperature uniformity and decrease both pressure drop and flow power compared to arrays of straight microchannels. The present study seeks to maximize the benefits of fractal-like branching channels by means of a gradient-based optimization algorithm. The algorithm identifies the geometric parameters that yield the highest ratio of benefit to cost; the benefit being the heat transfer with cost being flow power. The stream-wise pressure and wall temperature distributions were determined numerically using one-dimensional models validated using experimental diagnostics and computational flow analyses. Pressure distributions were used to assess flow power, and wall temperature was used as an optimization constraint. Several geometric constraints were imposed during optimization to ensure sufficient bonding area for fabrication, to maximize convective surface area and to prevent channel overlap. Three fractal-like devices were studied and optimized: a single-phase heat sink, a two-phase heat sink and a single-phase oil-to-water heat exchanger. The flow rate of the three devices was constrained using a maximum wall temperature constraint for the single-phase heat sink, the critical heat flux for the two-phase heat sink, and a fixed cold side mass flow rate and temperature rise in the case of the heat exchanger. The optimized solutions were found to depend highly on both the geometric and flow constraints imposed. As the terminal channel width was reduced, flow power was reduced in both single-phase and two-phase heat sinks. However, the flow power was increased in the heat exchanger due to the constrained volumetric flow rate. In addition, results show that if a maximum wall temperature constraint is employed, single-phase flow outperforms two-phase flow in terms of reduction in flow power. However when constrained by a critical heat flux, two-phase networks outperform single-phase networks by up to 150% Close

• 1530. [Article] Hydrology and geomorphic evolution of basaltic landscapes, High Cascades, Oregon

  The basaltic landscapes of the Oregon High Cascades form a natural laboratory for examining how geologic setting and history influence groundwater flowpaths, streamflow sensitivity to climate, and landscape ...

  Citation × Citation Citation Abstract Copy Title: Hydrology and geomorphic evolution of basaltic landscapes, High Cascades, Oregon Author: Jefferson, Anne (Anne Jarvis) The basaltic landscapes of the Oregon High Cascades form a natural laboratory for examining how geologic setting and history influence groundwater flowpaths, streamflow sensitivity to climate, and landscape evolution. In the High Cascades, highly permeable young basaltic lavas form extensive aquifers. These aquifers are the dominant sources of summer streamflow for the Willamette River and its tributary, the McKenzie River, whose watershed forms the study area. Groundwater is discharged at large volume, cold springs, and discharge, temperature, and isotopic measurements at seven springs were used to constrain groundwater patterns. Lava flow geometries have a significant influence on groundwater recharge areas and flowpaths, sometimes superseding topographic controls. Transit times to springs are ~3-14 years, and flowpaths are generally shallow and have limited contact with deeper geothermal systems, except at fault zones. Time-series analyses of historical discharge, precipitation, snow, and temperature records reveal that the distribution of permeable rocks and resultant groundwater systems strongly influence streamflow response to climatic forcing. The annual hydrograph is shaped by groundwater storage and release, but inter-annual streamflow variability is largely the result of climatic forcing. Over the past 60 years, warmer winters and earlier snowmelt have lengthened the summer recession period and decreased autumn minimum discharges in a groundwater-dominated watershed. A chronosequence of dated rock units, combined with field observations and measurements of slopes, contributing areas, and drainage densities, shows that the geologic history of a watershed controls the stage of drainage development. Groundwater flowpaths remain the dominant drainage mechanism for up to one million years, but as chemical weathering, glaciation, and other processes reduce the land surface permeability, channel networks grow up-slope of the springs. Within three million years, water is carried via a fully developed runoff-dominated stream network, groundwater discharge is insubstantial, and the landscape is shaped by fluvial and mass-wasting processes. The geology of a landscape is important for understanding hydrological processes at time scales ranging from a single season to several million years. Title: Hydrology and geomorphic evolution of basaltic landscapes, High Cascades, Oregon Author: Jefferson, Anne (Anne Jarvis) The basaltic landscapes of the Oregon High Cascades form a natural laboratory for examining how geologic setting and history influence groundwater flowpaths, streamflow sensitivity to climate, and landscape evolution. In the High Cascades, highly permeable young basaltic lavas form extensive aquifers. These aquifers are the dominant sources of summer streamflow for the Willamette River and its tributary, the McKenzie River, whose watershed forms the study area. Groundwater is discharged at large volume, cold springs, and discharge, temperature, and isotopic measurements at seven springs were used to constrain groundwater patterns. Lava flow geometries have a significant influence on groundwater recharge areas and flowpaths, sometimes superseding topographic controls. Transit times to springs are ~3-14 years, and flowpaths are generally shallow and have limited contact with deeper geothermal systems, except at fault zones. Time-series analyses of historical discharge, precipitation, snow, and temperature records reveal that the distribution of permeable rocks and resultant groundwater systems strongly influence streamflow response to climatic forcing. The annual hydrograph is shaped by groundwater storage and release, but inter-annual streamflow variability is largely the result of climatic forcing. Over the past 60 years, warmer winters and earlier snowmelt have lengthened the summer recession period and decreased autumn minimum discharges in a groundwater-dominated watershed. A chronosequence of dated rock units, combined with field observations and measurements of slopes, contributing areas, and drainage densities, shows that the geologic history of a watershed controls the stage of drainage development. Groundwater flowpaths remain the dominant drainage mechanism for up to one million years, but as chemical weathering, glaciation, and other processes reduce the land surface permeability, channel networks grow up-slope of the springs. Within three million years, water is carried via a fully developed runoff-dominated stream network, groundwater discharge is insubstantial, and the landscape is shaped by fluvial and mass-wasting processes. The geology of a landscape is important for understanding hydrological processes at time scales ranging from a single season to several million years. Close