Index Catalog // ScholarsArchive@OSU

Jet stream intraseasonal oscillations drive dominant ecosystem variations in Oregon’s summertime coastal upwelling system

Creator:: Bane, John M., Spitz, Yvette H., Letelier, Ricardo M., and Peterson, William T.
Abstract:: Summertime wind stress along the coast of the northwestern United States typically exhibits intraseasonal oscillations (ISOs) with periods from ≈15 to 40 days, as well as fluctuations on the 2- to 6-day “weather-band” and 1-day diurnal time scales. Coastal upwelling of cool, nutrient-rich water is driven by extended periods of...
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Full Text:: ‡, Ricardo M. Letelier‡, and William T. Peterson§ *Department of Marine Sciences, University of North

Modeling carbohydrate ballasting by Trichodesmium spp.

Creator:: White, Angelicque E., Spitz, Yvette H., and Letelier, Ricardo M.
Abstract:: We report the development of a numerical model simulating vertical movement of the cyanobacterium Trichodesmium spp. Given a range of physiological parameters derived from the literature, resultant model solutions allow us to explore the ecological significance of vertical migration by Trichodesmium colonies in a stratified oligotrophic oceanic system such as...
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Full Text:: carbohydrate ballasting by Trichodesmium spp. Angelicque E. White*, Yvette H. Spitz, Ricardo M. Letelier

Autonomous observations of in vivo fluorescence and particle backscattering in an oceanic oxygen minimum zone

Creator:: Whitmire, Amanda L., Letelier, Ricardo M., Villagran, Victor, and Ulloa, Osvaldo
Abstract:: The eastern South Pacific (ESP) oxygen minimum zone (OMZ) is a permanent hydrographic feature located directly off the coasts of northern Chile and Peru. The ESP OMZ reaches from coastal waters out to thousands of kilometers offshore, and can extend from the near surface to depths greater than 700 m....
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Full Text:: particle backscattering in an oceanic oxygen minimum zone A. L. Whitmire,1,* R. M. Letelier,1 V

Parameterizing the natural fluorescence kinetics of Thalassiosira weissflogii

Creator:: Laney, Samuel R., Letelier, Ricardo M., and Abbott, Mark R.
Abstract:: We examined variability in the natural fluorescence yield of a neritic diatom, Thalassiosira weissflogii, in continuous cultures. In this species, kinetics in natural fluorescence yield over time scales less than a photoperiod were characterized by sharp decreases, occurring at irradiance intensities that presumably coincide with the onset of nonphotochemical fluorescence...
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Full Text:: Laney, S. R., R. M. Letelier, and M. R. Abbott. Parameterizing the

Using lasers to probe the transient light absorption by proteorhodopsin in marine bacterioplankton

Creator:: Desiderio, Russell A., Laney, Samuel R., Letelier, Ricardo M., and Giovannoni, Stephen J.
Abstract:: We constructed an experimental apparatus that used lasers to provide the probe beams for measuring the transient absorption kinetics of bacterioplankton that contain proteorhodopsin, a microbial protein that binds retinal and is analogous to animal rhodopsin. With this approach we were able to observe photocycles characteristic of functioning retinylidene ion...
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Full Text:: proteorhodopsin in marine bacterioplankton Russell A. Desiderio,1,* Samuel R. Laney,1,3 Ricardo M. Letelier,1 and

Physiological Response of Crocosphaera watsonii to Enhanced and Fluctuating Carbon Dioxide Conditions

Creator:: Gradoville, Mary R., White, Angelicque E., and Letelier, Ricardo M.
Abstract:: We investigated the effects of elevated pCO₂ on cultures of the unicellular N₂-fixing cyanobacterium Crocosphaera watsonii WH8501. Using CO₂-enriched air, cultures grown in batch mode under high light intensity were exposed to initial conditions approximating current atmospheric CO₂ concentrations (~400 ppm) as well as CO₂ levels corresponding to low- and...
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Experimental assessment of diazotroph responses to elevated seawater pCO₂ in the North Pacific Subtropical Gyre

Creator:: Böttjer, Daniela, Karl, David M., Letelier, Ricardo M., Viviani, Donn A., and Church, Matthew J.
Abstract:: We examined short-term (24–72 h) responses of naturally occurringmarine N2 fixing microorganisms (termed diazotrophs) to abrupt increases in the partial pressure of carbon dioxide (pCO2) in seawater during nine incubation experiments conducted between May 2010 and September 2012 at Station ALOHA (A Long-term Oligotrophic Habitat Assessment) (22°45′N, 158°W) in the...
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Full Text:: elevated seawater pCO₂ in the North Pacific Subtropical Gyre Böttjer, D., D. M. Karl, R. M. Letelier, D

Paired windward and leeward biogeochemical time series reveal consistent surface ocean CO₂ trends across the Hawaiian Ridge

Creator:: Dore, John E., Church, Matthew J., Karl, David M., Sadler, Daniel W., and Letelier, Ricardo M.
Abstract:: Sustained time series have provided compelling evidence for progressive acidification of the surface oceans through exchange with the growing atmospheric reservoir of carbon dioxide. However, few long-term programs exist, and extrapolation of results from one site to larger oceanic expanses is hampered by the lack of spatial coverage inherent to...
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Diversity trumps acidification : lack of evidence for carbon dioxide enhancement of Trichodesmium community nitrogen or carbon fixation at Station ALOHA

Creator:: Gradoville, Mary R., White, Angelicque E., Böttjer, Daniela, Church, Matthew J., and Letelier, Ricardo M.
Abstract:: We conducted 11 independent short-term carbon dioxide (CO₂) manipulation experiments using colonies of the filamentous cyanobacteria Trichodesmium isolated on three cruises in the North Pacific Subtropical Gyre (NPSG). Dinitrogen (N₂) and carbon (C) fixation rates of these colonies were compared over CO₂ conditions ranging from ~ 18 Pa (equivalent to...
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Full Text:: . Church,2 and Ricardo M. Letelier 1 1 Oregon State University, College of Earth, Ocean, and Atmospheric

Phenology of particle size distributions and primary productivity in the North Pacific subtropical gyre (Station ALOHA)

Creator:: White, Angelicque E., Letelier, Ricardo M., Whitmire, Amanda L., Barone, Benedetto, Bidigare, Robert R., Church, Matthew J., and Karl, David M.
Abstract:: The particle size distribution (PSD) is a critical aspect of the oceanic ecosystem. Local variability in the PSD can be indicative of shifts in microbial community structure and reveal patterns in cell growth and loss. The PSD also plays a central role in particle export by influencing settling speed. Satellite-based...
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Full Text:: ., Letelier, R. M., Whitmire, A. L., Barone, B., Bidigare, R. R., Church, M. J., & Karl, D. M. (2015

Particle distributions and dynamics in the euphotic zone of the North Pacific Subtropical Gyre

Creator:: Barone, Benedetto, Bidigare, Robert R., Church, Matthew J., Karl, David M., Letelier, Ricardo M., and White, Angelicque E.
Abstract:: During the summer of 2012, we used laser diffractometry to investigate the temporal and vertical variability of the particle size spectrum (1.25–100 µm in equivalent diameter) in the euphotic zone of the North Pacific Subtropical Gyre. Particles measured with this optical method accounted for ∼40% of the particulate carbon stocks...
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Full Text:: ., Letelier, R. M., & White, A. E. (2015). Particle distributions and dynamics in the euphotic zone of the

Role of late winter mesoscale events in the biogeochemical variability of the upper water column of the North Pacific Subtropical Gyre

Creator:: Letelier, Ricardo M., Karl, David M., Abbott, Mark R., Flament, P., Freilich, Michael H., Lukas, Roger, and Strub, P. Ted
Abstract:: Continuous records of upper water column (0–150 m) temperature profiles, spectral distribution of downwelling irradiance, and phytoplankton solar-induced fluorescence at 25 m depth were obtained during the inaugural deployment of the Hawaii Air-sea Logging Experiment, A Long-term Oligotrophic Habitat Assessment (HALE ALOHA) mooring, near the Hawaii Ocean Time-series (HOT) Station...
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Physicochemical and biological controls on primary and net community production across northeast Pacific seascapes

Creator:: Kavanaugh, Maria T., Emerson, Steven R., Hales, Burke, Lockwood, Deirdre M., Quay, Paul D., and Letelier, Ricardo M.
Abstract:: The subarctic-subtropical transition zone in the North Pacific represents the second largest sink of atmospheric carbon dioxide in the world ocean, yet the relative importance of physical and biological processes in this uptake is debated. In a step toward understanding the spatiotemporal variability of environmental, physiological, and ecological factors that...
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Full Text:: Paul D. Quay,2 and Ricardo M. Letelier 3 1 Department of Marine Chemistry and Geochemistry, Woods Hole

Validation of Terra-MODIS phytoplankton chlorophyll fluorescence line height

Creator:: Hoge, Frank E., Lyon, Paul E., Swift, Robert N., Yungel, James K., Abbott, Mark R., Letelier, Ricardo M., and Esaias, Wayne E.
Abstract:: The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Terra spacecraft contains spectral bands that allow retrieval of solar-induced phytoplankton chlorophyll fluorescence emission radiance. Concurrent airborne laser-induced (and water-Raman normalized) phytoplankton chlorophyll fluorescence data is used to successfully validate the MODIS chlorophyll fluorescence line height (FLH) retrievals within Gulf Stream, continental...
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Full Text:: . Swift, James K. Yungel, Mark R. Abbott, Ricardo M. Letelier, Wayne E. Esaias The Moderate Resolution

Satellite-based prediction of pCO₂ in coastal waters of the eastern North Pacific

Creator:: Hales, Burke, Strutton, Peter G., Saraceno, Martin, Letelier, Ricardo, Takahashi, Taro, Feely, Richard, Sabine, Christopher, and Chavez, Francisco
Abstract:: Continental margin carbon cycling is complex, highly variable over a range of space and time scales, and forced by multiple physical and biogeochemical drivers. Predictions of globally significant air–sea CO₂ fluxes in these regions have been extrapolated based on very sparse data sets. We present here a method for predicting...
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Full Text:: Pacific Burke Hales a,⇑, Peter G. Strutton g, Martin Saraceno b,c, Ricardo Letelier a, Taro Takahashi d

Spatial and Spectral Resolution Considerations for Imaging Coastal Waters

Creator:: Davis, Curtiss O., Kavanaugh, Maria, Letelier, Ricardo, Bissett, W. Paul, and Kohler, David
Abstract:: Current ocean color sensors, for example SeaWiFS and MODIS, are well suited for sampling the open ocean. However, coastal environments are spatially and optically more complex and require more frequent sampling and higher spatial resolution sensors with additional spectral channels. We have conducted experiments with data from Hyperion and airborne...
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Short-term variability in euphotic zone biogeochemistry and primary productivity at Station ALOHA: A case study of summer 2012

Creator:: Wilson, Samuel T., Barone, Benedetto, Ascani, Francois, Bidigare, Robert R., Church, Matthew J., del Valle, Daniela A., Dyhrman, Sonya T., Ferrón, Sara, Fitzsimmons, Jessica N., Juranek, Laurie W., Kolber, Zbigniew S., Letelier, Ricardo M., Martínez‐García, Sandra, Nicholson, David P., Richards, Kelvin J., Rii, Yoshimi M., Rouco, Mónica, Viviani, Donn A., White, Angelicque E., Zehr, Jonathan P., and Karl, David M.
Abstract:: Time-series observations are critical to understand the structure, function, and dynamics of marine ecosystems. The Hawaii Ocean Time-series program has maintained near-monthly sampling at Station ALOHA (22°45′N, 158°00′W) in the oligotrophic North Pacific Subtropical Gyre (NPSG) since 1988 and has identified ecosystem variability over seasonal to interannual timescales. To further...
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A two-way nested simulation of the oceanic circulation in the Southwestern Atlantic

Creator:: Combes, Vincent and Matano, Ricardo P.
Abstract:: This article presents the results of a high-resolution (1/12°), two-way nested simulation of the oceanic circulation in the southwestern Atlantic region. A comparison between the model results and extant observations indicates that the nested model has skill in reproducing the best-known aspects of the regional circulation, e.g., the volume transport...
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Full Text:: oceanic circulation in the Southwestern Atlantic Vincent Combes1 and Ricardo P. Matano1 1College of Earth

The Low-Frequency Variability of the Southern Ocean Circulation

Creator:: Giarolla, Emanuel and Matano, Ricardo P.
Abstract:: Abstract: Long time series of sea surface height (SSH), sea surface temperature, and wind stress curl are used to determine the main modes of low-frequency variability of the Southern Ocean (SO) circulation. The dominant mode is a trend of increasing SSH at an average rate of 3.3 mm yr(-1). Similar...
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Full Text:: Southern Ocean Circulation EMANUEL GIAROLLA CPTEC/INPE, S~ao Jos�e dos Campos, Brazil RICARDO P. MATANO

Trends in the Brazil/Malvinas Confluence region

Creator:: Combes, Vincent and Matano, Ricardo P.
Abstract:: Observations show abrupt changes in the oceanic circulation of the southwestern Atlantic. These studies report a southward drift of the Brazil/Malvinas Confluence (BMC) and a change in the spectral characteristics of the Malvinas Current (MC) transport. We address the cause of these changes using the result of a high-resolution numerical...
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Full Text:: /sa-termsofuse Trends in the Brazil/Malvinas Confluence region Vincent Combes1 and Ricardo P

Agave salmiana Plant Communities in Central Mexico as Affected by Commercial Use

Creator:: Martinez Salvador, Martin, Mata-Gonzalez, Ricardo, Morales Nieto, Carlos, and Valdez-Cepeda, Ricardo
Abstract:: Agave salmiana is a native plant species harvested for the commercial production of mezcal (Agave spirits) in the highlands of central Mexico. The objective of this study was to identify vegetation changes in natural communities where A. salmiana has been differentially harvested for commercial purposes. Three plant community categories were...
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Full Text:: -González, Carlos Morales Nieto, Ricardo Valdez-3 Cepeda 4 5 6 M. Martínez Salvador, C. Morales

An efficient method to estimate processing rates in streams

Creator:: Gonz alez-Pinz on, Ricardo and Haggerty, Roy
Abstract:: We provide an efficient method to estimate processing rates through simple algebraic relationships derived from the transient storage model equations. The method is based on the transport equations, but eliminates the need to calibrate highly uncertain (and intermediate) parameters. We demonstrate that under some common stream transport conditions dispersion does...
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Full Text:: processing rates in streams Ricardo Gonz�alez-Pinz�on1,2 and Roy Haggerty1 Received 26 April 2013; revised

Quantifying spatial differences in metabolism in headwater streams

Creator:: Gonzalez-Pinzon, Ricardo, Haggerty, Roy, and Argerich, Alba
Abstract:: Stream functioning includes simultaneous interaction among solute transport, nutrient processing, and metabolism. Metabolism is measured with methods that have limited spatial representativeness and are highly uncertain. These problems restrict development of methods for up-scaling biological processes that mediate nutrient processing. We used the resazurin–resorufin (Raz-Rru) tracer system to estimate metabolism...
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Full Text:: September 2014 2 3 Quantifying spatial differences in metabolism in headwater streams 4 5 Ricardo

The Upstream Spreading of Bottom-Trapped Plumes

Creator:: Matano, Ricardo P. and Palma, Elbio D.
Abstract:: It is well known that numerical simulations of freshwater discharges produce plumes that spread in the direction opposite to that of the propagation of coastally trapped waves (the upstream direction). The lack of a theory explaining these motions in unforced environments deemed the numerical results suspect. Thus, it became a...
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Full Text:: Plumes RICARDO P. MATANO College of Oceanic and Atmospheric Sciences, Oregon State University

On the Upwelling of Downwelling Currents

Creator:: Matano, Ricardo P. and Palma, Elbio D.
Abstract:: The term “downwelling currents” refers to currents with a downslope mass flux in the bottom boundary layer. Examples are the Malvinas and Southland Currents in the Southern Hemisphere and the Oyashio in the Northern Hemisphere. Although many of these currents generate the same type of highly productive ecosystems that is...
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Full Text:: On the Upwelling of Downwelling Currents RICARDO P. MATANO

The Spindown of Bottom-Trapped Plumes

Creator:: Matano, Ricardo P. and Palma, Elbio D.
Abstract:: This note considers the decay of a bottom-trapped freshwater plume after the causative freshwater inflow has ceased. It is shown that shortly after the low-density inflow stops, the barotropic pressure field that it created radiates away and the ocean circulation becomes controlled by baroclinic pressure gradients generated by the remnants...
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Full Text:: Bottom-Trapped Plumes RICARDO P. MATANO College of Oceanic and Atmospheric Sciences, Oregon State

The Impact of Boundary Conditions on the Upstream Spreading of Bottom-Trapped Plumes

Creator:: Matano, Ricardo P. and Palma, Elbio D.
Abstract:: This study shows that simulations of bottom-trapped plumes in periodic or closed domains generate a spurious cyclonic current that arrests the natural tendency of the plume to move upstream. Furthermore, it also shows that attempts to obstruct the upstream spreading lead to a bias of the fundamental characteristics of the...
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Full Text:: Upstream Spreading of Bottom-Trapped Plumes RICARDO P. MATANO College of Earth, Ocean, and Atmospheric

Scaling and predicting solute transport processes in streams

Creator:: Gonz alez-Pinz on, Ricardo, Haggerty, Roy, and Dentz, Marco
Abstract:: We investigated scaling of conservative solute transport using temporal moment analysis of 98 tracer experiments (384 breakthrough curves) conducted in 44 streams located on five continents. The experiments span 7 orders of magnitude in discharge (10⁻ ³ to 10³ m³/s), span 5 orders of magnitude in longitudinal scale (10¹ to...
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Full Text:: transport processes in streams Ricardo Gonz�alez-Pinz�on,1 Roy Haggerty,1 and Marco Dentz2 Received 27

Coupled transport and reaction kinetics control the nitrate source-sink function of hyporheic zones

Creator:: Zarnetske, Jay P., Haggerty, Roy, Wondzell, Steven M., Bokil, Vrushali A., and Gonzalez-Pinzon, Ricardo
Abstract:: The fate of biologically available nitrogen (N) and carbon (C) in stream ecosystems is controlled by the coupling of physical transport and biogeochemical reaction kinetics. However, determining the relative role of physical and biogeochemical controls at different temporal and spatial scales is difficult. The hyporheic zone (HZ), where groundwater–stream water...
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Full Text:: control the nitrate source-sink function of hyporheic zones Jay P. Zarnetske,1 Roy Haggerty,2 Steven M

Una especie nueva y peculiar de Graphis (Ascomycota: Ostropales: Graphidaceae) de la selva alta perennifolia de Los Tuxtlas, Veracruz, México

Creator:: Bárcenas-Peña, Alejandrina, Miranda-González, Ricardo, and de los Ángeles Herrera-Campos, María
Abstract:: Graphis robertusii Bárcenas-Peña, Herrera-Campos y Miranda es descrita por primera vez para la selva alta perennifolia de Los Tuxtlas, Veracruz. Es una especie conspicua caracterizada por lirelas erumpentes con margen talino lateral, labios no estriados blancos pruinosos, excípulo completamente carbonizado, himenio insperso, esporas transversalmente septadas y ácidos estíctico, salazínico y...
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Full Text:: -Campos, M. (2015). Una especie nueva y peculiar de Graphis (Ascomycota: Ostropales: Graphidaceae) de la

Shelfbreak upwelling induced by alongshore currents: analytical and numerical results

Creator:: Miller, Robert N., Matano, Ricardo P., and Palma, Elbio D.
Abstract:: Alongshore flow in the direction of propagation of coastal trapped waves can result in upwelling at the shelfbreak. The intensity of this upwelling can be comparable in magnitude to wind-driven coastal upwelling, with its associated ecological features. Recent numerical experiments by Matano & Palma indicate that this upwelling results from...
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Full Text:: : analytical and numerical results Robert N. Miller1,2†, Ricardo P. Matano1 and Elbio D. Palma3 1 College of

Geostrophic Velocity Measurement Techniques for the Meridional Overturning Circulation and Meridional Heat Transport in the South Atlantic

Creator:: Perez, Renellys C., Garzoli, Silvia L., Meinen, Christopher S., and Matano, Ricardo P.
Abstract:: Two ocean general circulation models are used to test the ability of geostrophic velocity measurement systems to observe the meridional overturning circulation (MOC) and meridional heat transport (MHT) in the South Atlantic. Model sampling experiments are conducted at five latitudes (between 15° and 34.5°S) spanning the range of extratropical current...
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Full Text:: . MEINEN NOAA/Atlantic Oceanographic and Meteorological Laboratory, Miami, Florida RICARDO P. MATANO

Measuring aerobic respiration in stream ecosystems using the resazurin-resorufin system

Creator:: Gonzalez-Pinzon, Ricardo, Haggerty, Roy, and Myrold, David D.
Abstract:: The use of smart tracers to study hydrologic systems is becoming more widespread. Smart tracers are compounds that irreversibly react in the presence of a process or condition under investigation. Resazurin (Raz) is a smart tracer that undergoes an irreversible reduction to resorufin (Rru) in the presence of cellular metabolic...
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Full Text:: -resorufin system Ricardo González-Pinzón,1 Roy Haggerty,1 and David D. Myrold2 Received 28 January 2012

Predicting foundation bunchgrass species abundances: model-assisted decision-making in protected-area sagebrush steppe

Creator:: Rodhouse, Thomas J., Irvine, Kathryn M., Sheley, Roger L., Smith, Brenda S., Hoh, Shirley, Esposito, Daniel M., and Mata-Gonzalez, Ricardo
Abstract:: Foundation species are structurally dominant members of ecological communities that can stabilize ecological processes and influence resilience to disturbance and resistance to invasion. Being common, they are often overlooked for conservation but are increasingly threatened from land use change, biological invasions, and over‐exploitation. The pattern of foundation species abundances over...
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Full Text:: abundances: model-assisted decision-making in protected-area sagebrush steppe Rodhouse, T. J., Irvine, K. M

Identification of Novel Gammaherpesviruses in Ocelots (Leopardus pardalis) and Bobcats (Lynx rufus) in Panama and Colorado, USA

Creator:: Lozano, Caitlin C., Sweanor, Linda L., Wilson-Henjum, Grete, Kays, Roland W., Moreno, Ricardo, VandeWoude, Sue, and Troyer, Ryan M.
Abstract:: Gammaherpesviruses (GHVs) have been identified in many species and are often associated with disease. Recently, we characterized three novel felid GHVs in domestic cats, bobcats, and pumas. In this study we sought to determine whether free ranging ocelots (Leopardus pardalis) and bobcats (Lynx rufus) are infected with additional GHVs. We...
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Full Text:: . Sweanor,1 Grete Wilson-Henjum,1 Roland W. Kays,2,3 Ricardo 3 Moreno,3,4 Sue VandeWoude,1 and Ryan M

Non-Native Plant Invasion along Elevation and Canopy Closure Gradients in a Middle Rocky Mountain Ecosystem

Creator:: Averett, Joshua P., McCune, Bruce, Parks, Catherine G., Naylor, Bridgett J., DelCurto, Tim, and Mata-González, Ricardo
Abstract:: Mountain environments are currently among the ecosystems least invaded by non-native species; however, mountains are increasingly under threat of non-native plant invasion. The slow pace of exotic plant invasions in mountain ecosystems is likely due to a combination of low anthropogenic disturbances, low propagule supply, and extreme/steep environmental gradients. The...
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A review of nitrogen isotopic alteration in marine sediments

Creator:: Robinson, Rebecca S., Kienast, Markus, Albuquerque, Ana Luiza, Altabet, Mark, Contreras, Sergio, De Pol Holz, Ricardo, Dubois, Nathalie, Francois, Roger, Galbraith, Eric, Hsu, Ting-Chang, Ivanochko, Tara, Jaccard, Samuel, Kao, Shuh-Ji, Kiefer, Thorsten, Kienast, Stephanie, Lehmann, Moritz, Martinez, Philippe, McCarthy, Matthew, Mobius, Jurgen, Pedersen, Tom, Quan, Tracy M., Ryabenko, Evgeniya, Schmittner, Andreas, Schneider, Ralph, Schneider-Mor, Aya, Shigemitsu, Masahito, Sinclair, Dan, Somes, Christopher, Studer, Anja, Thunell, Robert, and Yang, Jin-Yu
Abstract:: Nitrogen isotopes are an important tool for evaluating past biogeochemical cycling from the paleoceanographic record. However, bulk sedimentary nitrogen isotope ratios, which can be determined routinely and at minimal cost, may be altered during burial and early sedimentary diagenesis, particularly outside of continental margin settings. The causes and detailed mechanisms...
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Full Text:: Contreras,5 Ricardo De Pol Holz,6 Nathalie Dubois,7 Roger Francois,8 Eric Galbraith,9 Ting-Chang Hsu,10

A field comparison of multiple techniques to quantify groundwater–surface-water interactions

Creator:: González-Pinzón, Ricardo, Ward, Adam S., Hatch, Christine E., Wlostowski, Adam N., Singha, Kamini, Gooseff, Michael N., Haggerty, Roy, Harvey, Judson W., Cirpka, Olaf A., and Brock, James T.
Abstract:: Groundwater–surface-water (GW-SW) interactions in streams are difficult to quantify because of heterogeneity in hydraulic and reactive processes across a range of spatial and temporal scales. The challenge of quantifying these interactions has led to the development of several techniques, from centimeter-scale probes to whole-system tracers, including chemical, thermal, and electrical...
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Full Text:: ., Gooseff, M. N., ... & Brock, J. T. (2015). A field comparison of multiple techniques to quantify

Effects of supplementation of calcium salts of polyunsaturated fatty acids on serum concentrations of progesterone and insulin of pregnant dairy cows

Creator:: Moriel, Philipe, Cappellozza, Bruno Ieda, Ferraretto, Luiz Felipe, Aboin, Augusto Cossolino, Rodrigues Vieira, Fernanda Victor, Rodrigues, Ricardo de Oliveira, Cooke, Reinaldo Fernandes, and Moraes Vasconcelos, José Luiz
Abstract:: Forty-five non-lactating, pregnant Holstein animals (18 heifers and 27 multiparous cows; BW = 561±114 kg; BCS = 2.9±0.3; days pregnant = 110±56 d) were stratified by initial BW and BCS, and randomly assigned to receive daily (as-fed basis) 0.50 kg of ground corn plus 0.22 kg of kaolin (CON), calcium...
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Full Text:: . C., Vieira, F. V. R., Rodrigues, R. D. O., ... & Vasconcelos, J. L. M. (2014). Effects of

Temporal Genetic Variance and Propagule-Driven Genetic Structure Characterize Naturalized Rainbow Trout (Oncorhynchus mykiss) from a Patagonian Lake Impacted by Trout Farming

Creator:: Benavente, Javiera N., Seeb, Lisa W., Seeb, James E., Arismendi, Ivan, Hernández, Cristián E., Gajardo, Gonzalo, Galleguillos, Ricardo, Cádiz, Maria I., Musleh, Selim S., and Gomez-Uchida, Daniel
Abstract:: Knowledge about the genetic underpinnings of invasions—a theme addressed by invasion genetics as a discipline—is still scarce amid well documented ecological impacts of non-native species on ecosystems of Patagonia in South America. One of the most invasive species in Patagonia’s freshwater systems and elsewhere is rainbow trout (Oncorhynchus mykiss). This...
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Full Text:: , James E. Seeb2, Ivan Arismendi3, Cristián E. Hernández1, Gonzalo Gajardo4, Ricardo Galleguillos5, Maria

Is there no “I” in team? Potential bias in key informant interviews when asking individuals to represent a collective perspective

Creator:: Fleming, Whitney, King, Brittany, Robinson, Kerrick, Wade, Eric, Erickson, Brian, Delie, Jackie, de Ycaza, Ricardo, Trimbach, David, Spalding, Ana, and Biedenweg, Kelly
Abstract:: This paper sought to understand the extent to which, and how individuals use personal or collective language when asked to articulate sense of place from a collective perspective. Understanding a collective sense of place could illuminate place-based connections in natural resource industries, where it is as groups or as institutions...
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Full Text:: , Brian EricksonID 1, Jackie Delie1, Ricardo de Ycaza3,4, David Trimbach1, Ana Spalding3,4, Kelly

Western Land Managers will Need all Available Tools for Adapting to Climate Change, Including Grazing: A Critique of Beschta et al.

Creator:: Svejcar, Tony, Boyd, Chad, Davies, Kirk, Madsen, Matthew, Bates, Jonathan D., Sheley, Roger, Marlow, Clayton, Bohnert, David W., Borman, Mike, Mata-Gonzalez, Ricardo, Buckhouse, John, Stringham, Tamzen, Perryman, Barry, Swanson, Sherman, Tate, Kenneth, George, Mel, Ruyle, George, Roundy, Bruce, Call, Chris, Jensen, Kevin, Launchbaugh, Karen, Gearhart, Amanda, Vermeire, Lance, Tanaka, John, Derner, Justin, Frasier, Gary, and Havstad, Kris
Abstract:: In a previous article, Beschta et al. (Environ Manag 51(2):474–491, 2013) argue that grazing by large ungulates (both native and domestic) should be eliminated or greatly reduced on western public lands to reduce potential climate change impacts. The authors did not present a balanced synthesis of the scientific literature, and...
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Full Text:: Critique of Beschta et al. Svejcar, T., Boyd, C., Davies, K., Madsen, M., Bates, J., Sheley, R

A Numerical Modeling Study of the Upwelling Source Waters along the Oregon Coast during 2005

Creator:: Rivas, David and Samelson, R. M.
Abstract:: Regional ocean circulation along the Oregon coast is studied numerically for forcing fields derived from year 2005 and climatological-mean conditions. The primary object is to study directly the Lagrangian pathways by which fluid arrives in the Oregon upwelling zone. Roughly half of the upwelling fluid is found to arrive in...
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Full Text:: Source Waters along the Oregon Coast during 2005 DAVID RIVAS* AND R. M. SAMELSON College of Oceanic and

A social and ecological assessment of tropical land uses at multiple scales: the Sustainable Amazon Network

Creator:: Gardner, Toby A., Ferreira, Joice, Barlow, Jos, Lees, Alexander C., Parry, Luke, Guimarães Vieira, Ima Célia, Berenguer, Erika, Abramovay, Ricardo, Aleixo, Alexandre, Andretti, Christian, Aragão, Luiz E. O. C., Araujo, Ivanei, Bardgett, Richard D., Batistella, Mateus, Begotti, Rodrigo Anzolin, Beldini, Troy, de Blas, Driss Ezzine, Braga, Rodrigo Fagundes, Braga, Danielle de Lima, de Brito, Janaina Gomes, de Ávila, Williams Souza, de Camargo, Plinio Barbosa, dos Santos, Fabiane Campos, de Oliveira, Vívian Campos, Nunes Cordeiro, Amanda Cardoso, Cardoso, Thiago Moreira, de Carvalho, Deborah Reis, Castelani, Sergio Andre, Mario Chaul, Julio Cezar, Cerri, Carlos Eduardo, Costa, Francisco de Assis, Furtado da Costa, Carla Daniele, Coudel, Emilie, Coutinho, Alexandre Camargo, Cunha, Denis, D'Antona, Alvaro, Dezincourt, Joelma, Dias-Silva, Karina, Durigan, Mariana, Dalla Mora Esquerdo, Julio Cesar, Feres, Jose, de Barros Ferraz, Silvio Frosini, de Melo Ferreira, Amanda Estefania, Fiorini, Ana Carolina, Flores da Silva, Lenise Vargas, Frazao, Fabio Soares, Garrett, Rachel, Gomes, Alessandra dos Santos, Goncalves, Karoline da Silva, Guerrero, Jose Benito, Hamada, Neusa, Hughes, Robert M., Igliori, Danilo Carmago, Jesus, Ederson da Conceicao, Juen, Leandro, Junior, Miercio, de Oliveira Junior, Jose Max Barbosa, de Oliveira Junior, Raimundo Cosme, Souza Junior, Carlos, Kaufmann, Phil, Korasaki, Vanesca, Leal, Cecilia Gontijo, Leitao, Rafael, Lima, Natalia, Lopes Almeida, Maria de Fatima, Lourival, Reinaldo, Louzada, Julio, Mac Nally, Ralph, Marchand, Sebastien, Maues, Marcia Motta, Moreira, Fatima M. S., Morsello, Carla, Moura, Nargila, Nessimian, Jorge, Nunes, Samia, Fonseca Oliveira, Victor Hugo, Pardini, Renata, Pereira, Heloisa Correia, Pompeu, Paulo Santos, Ribas, Carla Rodrigues, Rossetti, Felipe, Schmidt, Fernando Augusto, da Silva, Rodrigo, Viana Martins da Silva, Regina Celia, Morello Ramalho da Silva, Thiago Fonseca, Silveira, Juliana, Siqueira, Joao Victor, de Carvalho, Teotonio Soares, Solar, Ricardo R. C., Holanda Tancredi, Nicola Saverio, Thomson, James R., Torres, Patricia Carignano, Vaz-de-Mello, Fernando Zagury, Stulpen Veiga, Ruan Carlo, Venturieri, Adriano, Viana, Cecilia, Weinhold, Diana, Zanetti, Ronald, and Zuanon, Jansen
Abstract:: Science has a critical role to play in guiding more sustainable development trajectories. Here, we present the Sustainable Amazon Network (Rede Amazonia Sustentavel, RAS): a multidisciplinary research initiative involving more than 30 partner organizations working to assess both social and ecological dimensions of land-use sustainability in eastern Brazilian Amazonia. The...
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Full Text:: , Ruan João Victor Siqueira, Teotônio Soares de Carvalho, Ricardo R. C. Solar, Nicola Savério Holanda

Satellite-based detection and monitoring of phytoplankton blooms along the Oregon coast

Creator:: McKibben, S. M., Strutton, P. G., Foley, D. G., Peterson, T. D., and White, A. E.
Abstract:: We have applied a normalized difference algorithm to 8 day composite chlorophyll-a (CHL) and fluorescence line height (FLH) imagery obtained from the Moderate Resolution Imaging Spectroradiometer aboard the Aqua spacecraft in order to detect and monitor phytoplankton blooms in the Oregon coastal region. The resulting bloom products, termed CHL[subscript rel]...
Resource Type:: Article
Full Text:: . References Abbott, M. R., and R. M. Letelier (1999), Algorithm theoretical basis document chlorophyll

Biological production in the NE Pacific and its influence on air-sea CO2 flux: Evidence from dissolved oxygen isotopes and O2/Ar

Creator:: Juranek, L. W., Quay, P. D., Feely, R. A., Lockwood, D., Karl, D. M., and Church, M. J.
Abstract:: We determine rates of gross photosynthetic O₂ production (GOP) and net community O₂ production (NCP) using the triple oxygen isotope and O₂/Ar approach on two spring and two late summer meridional transects of the NE Pacific. Observed GOP and NCP in the subtropical (89 ± 9 and 8.3 ± 1.3...
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Full Text:: . Juranek,1,2,3 P. D. Quay,4 R. A. Feely,2 D. Lockwood,4 D. M. Karl,5 and M. J. Church5 Received 13 July

Norms Governing Urban African American Adolescents' Sexual and Substance-Using Behavior

Creator:: Dolcini, M. Margaret, Catania, Joseph A., Harper, Gary W., Watson, Susan E., Ellen, Jonathan M., and Towner, Senna L.
Abstract:: Using a probability-based neighborhood sample of urban African American youth and a sample of their close friends (N = 202), we conducted a one-year longitudinal study to examine key questions regarding sexual and drug using norms. The results provide validation of social norms governing sexual behavior, condom use, and substance...
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Full Text:: M. Margaret Dolcinial and Joseph A. Cataniaa Oregon State University Gary W. Harperb DePaul

The United States' Next Generation of Atmospheric Composition and Coastal Ecosystem Measurements: NASA's Geostationary Coastal and Air Pollution Events (GEO-CAPE) Mission

Creator:: Fishman, J., Iraci, L. T., Al-Saadi, J., Chance, K., Chavez, F., Chin, M., Coble, P., Davis, C., DiGiacomo, P. M., Edwards, D., Eldering, A., Goes, J., Herman, J., Hu, C., Jacob, D. J., Jordan, C., Kawa, S. R., Key, R., Liu, X., Lohrenz, S., Mannino, A., Natraj, V., Neil, D., Neu, J., Newchurch, M., Pickering, K., Salisbury, J., Sosik, H., Subramaniam, A., Tzortziou, M., Wang, J., and Wang, M.
Abstract:: The Geostationary Coastal and Air Pollution Events (GEO-CAPE) mission was recommended by the National Research Council's (NRC's) Earth Science Decadal Survey to measure tropospheric trace gases and aerosols and coastal ocean phytoplankton, water quality, and biogeochemistry from geostationary orbit, providing continuous observations within the field of view. To fulfill the...
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Full Text:: . chance, F. chavez, m. chin, P. cobLe, c. davis, P. m. diGiacomo, d. edwards, a. eLderinG, J. Goes, J

A springtime source of toxic Pseudo-nitzschia cells on razor clam beaches in the Pacific Northwest

Creator:: Hickey, Barbara M., Trainer, Vera L., Kosro, P. Michael, Adams, Nicolaus G., Connolly, Thomas P., Kachel, Nancy B., and Geier, Susan L.
Abstract:: Concentrations of domoic acid (DA) above the regulatory limit in Washington coast razor clams are usually higher on northern beaches from summer to fall. Recent field studies have confirmed that the primary source of toxic Pseudo-nitzschia (PN) cells in those seasons is a semi-retentive topographically trapped seasonal eddy located offshore...
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Full Text:: springtime source of toxic Pseudo-nitzschia cells on razor clam beaches in the Pacific Northwest Barbara M

Environmental drivers and reproductive consequences of variation in the diet of a marine predator

Creator:: Gladics, Amanda J., Suryan, Robert M., Parrish, Julia K., Horton, Cheryl A., Daly, Elizabeth A., and Peterson, William T.
Abstract:: Ocean conditions can greatly impact lower trophic level prey assemblages in marine ecosystems, with effects of ocean state propagating to higher trophic levels. In many regions throughout their range, common murre (Uria aalge) exhibit narrow dietary breadth in feeding chicks and therefore are vulnerable to recruitment failures of dominant prey...
Resource Type:: Article
Full Text:: reproductive consequences of variation in the diet of a marine predator Gladics, A. J., Suryan, R. M

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