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Sediment transport, turbidity, and dissolved oxygen responses to annual streambed drawdowns for downstream fish passage in a flood control reservoir Sediment transport, turbidity, and dissolved oxygen responses to annual streambed drawdowns for downstream fish passage in a flood control reservoir

Sediment transport, turbidity, and dissolved oxygen were evaluated during six consecutive water years (2013–2018) of drawdowns of a flood control reservoir in the upper Willamette Valley, Oregon, USA. The drawdowns were conducted to allow volitional passage of endangered juvenile chinook salmon through the dam's regulating outlets by lowering the reservoir elevation to a point where the...
Authors
Liam N. Schenk, Heather M. Bragg

Egg retention of high-latitude sockeye salmon (Oncorhynchus nerka) in the Pilgrim River, Alaska, during the Pacific marine heatwave of 2014–2016 Egg retention of high-latitude sockeye salmon (Oncorhynchus nerka) in the Pilgrim River, Alaska, during the Pacific marine heatwave of 2014–2016

Ocean and freshwater conditions can influence spawning success of Pacific salmon (Oncorhynchus spp.) by governing the energy content of fish at the start of and during the spawning migration. Ocean conditions determine the energy stores of fish at the freshwater entry, while freshwater conditions determine how quickly stored energy is depleted as individuals migrate to spawning grounds...
Authors
Michael P. Carey, Vanessa R. von Biela, Ashley Dunker, Kevin D. Keith, Merlyn Schelske, Charlie Lean, Christian E. Zimmerman

New geochemical tools for investigating resource and energy functions at deep-sea cold seeps using amino-acid δ15N in chemosymbiotic mussels (Bathymodiolus childressi) New geochemical tools for investigating resource and energy functions at deep-sea cold seeps using amino-acid δ15N in chemosymbiotic mussels (Bathymodiolus childressi)

In order to reconstruct the ecosystem structure of chemosynthetic environments in the fossil record, geochemical proxies must be developed. Here, we present a suite of novel compound-specific isotope parameters for tracing chemosynthetic production with a focus on understanding nitrogen dynamics in deep-sea cold seep environments. We examined the chemosymbiotic bivalve Bathymodiolus...
Authors
Natasha Vokhshoori, Matt McCarthy, Hilary Close, Amanda Demopoulos, Nancy G. Prouty

Multivariate Bayesian clustering using covariate-informed components with application to boreal vegetation sensitivity Multivariate Bayesian clustering using covariate-informed components with application to boreal vegetation sensitivity

Climate change is impacting both the distribution and abundance of vegetation, especially in far northern latitudes. The effects of climate change are different for every plant assemblage and vary heterogeneously in both space and time. Small changes in climate could result in large vegetation responses in sensitive assemblages but weak responses in robust assemblages. But, patterns and...
Authors
Henry R. Scharf, Ann M. Raiho, Sierra Pugh, Carl A. Roland, David K. Swanson, Sarah E. Stehn, Mevin Hooten

Nutrient limitation of algae and macrophytes in streams: Integrating laboratory bioassays, field experiments, and field data Nutrient limitation of algae and macrophytes in streams: Integrating laboratory bioassays, field experiments, and field data

Successful eutrophication control strategies need to address the limiting nutrient. We conducted a battery of laboratory and in situ nutrient-limitation tests with waters collected from 9 streams in an agricultural region of the upper Snake River basin, Idaho, USA. Laboratory tests used the green alga Raphidocelis subcapitata, the macrophyte Lemna minor (duckweed) with native epiphytes...
Authors
Christopher A. Mebane, Andrew M. Ray, Amy M Marcarelli

Land-based sediment sources and transport to southwest Puerto Rico coral reefs after Hurricane Maria, May 2017 to June 2018 Land-based sediment sources and transport to southwest Puerto Rico coral reefs after Hurricane Maria, May 2017 to June 2018

The effects of runoff from land on nearshore ecosystems, including coral reef communities, are influenced by both sediment supply and removal by coastal processes. Integrated studies across the land-sea interface describing sources and transport of terrestrial sediment and its nearshore fate allow reef protection initiatives to target key onshore and offshore areas. Geochemical...
Authors
Renee K. Takesue, Clark E. Sherman, Aaron O. Reyes, Olivia M. Cheriton, Natalia I. Ramirez, Roberto Viqueira Rios, Curt D. Storlazzi

When hazard avoidance is not an option: Lessons learned from monitoring the postdisaster Oso landslide, USA When hazard avoidance is not an option: Lessons learned from monitoring the postdisaster Oso landslide, USA

On 22 March 2014, a massive, catastrophic landslide occurred near Oso, Washington, USA, sweeping more than 1 km across the adjacent valley flats and killing 43 people. For the following 5 weeks, hundreds of workers engaged in an exhaustive search, rescue, and recovery effort directly in the landslide runout path. These workers could not avoid the risks posed by additional large-scale...
Authors
Mark E. Reid, Jonathan W. Godt, Richard G LaHusen, Stephen L Slaughter, Thomas C. Badger, Brian D. Collins, William H. Schulz, Rex L. Baum, Jeffrey A. Coe, Edwin L Harp, Kevin M. Schmidt, Richard M. Iverson, Joel B. Smith, Ralph A. Haugerud, David L. George

Borreliosis transmission from ticks to humans associated with desert tortoise burrows: Examples of tick-borne relapsing fever in the Mojave Desert Borreliosis transmission from ticks to humans associated with desert tortoise burrows: Examples of tick-borne relapsing fever in the Mojave Desert

Ticks transmit pathogens and parasitize wildlife in turn causing zoonotic diseases in many ecosystems. Argasid ticks, such as Ornithodoros spp., harbor and transmit Borrelia spp., resulting in tick-borne relapsing fever (TBRF) in people. In the western United States, TBRF is typically associated with the bite of an infected Ornithodoros hermsi tick found in habitats at high elevations (...
Authors
Molly J Bechtel, K. Kristina Drake, Todd Esque, Nathan C Nieto, Jeffrey T. Foster, Mike B Teglas

Regional occurrence of aqueous tungsten and relations with antimony, arsenic and molybdenum concentrations (Sardinia, Italy) Regional occurrence of aqueous tungsten and relations with antimony, arsenic and molybdenum concentrations (Sardinia, Italy)

Tungsten (W) is rarely found in natural waters, yet it can be introduced into the food chain and cause potentially toxic effects. Uptake of W by plants and vegetables, or trace presence of W in drinking water are possible vectors for ingestion of W by humans. The latter is recognized as a possible cause of lymphatic leukemia. Increased uses of W might result in a degradation of water...
Authors
Rosa Cidu, Riccardo Biddau, Franco Frau, Richard B. Wanty, Stefano Naitza

The marine terraces of Santa Cruz Island, California: Implications for glacial isostatic adjustment models of last-interglacial sea-level history The marine terraces of Santa Cruz Island, California: Implications for glacial isostatic adjustment models of last-interglacial sea-level history

Glacial isostatic adjustment (GIA) models hypothesize that along coastal California, last interglacial (LIG, broadly from ~130 to ~115 ka) sea level could have been as high as +11 m to +13 m, relative to present, substantially higher than the commonly estimated elevation of +6 m. Areas with low uplift rates can test whether such models are valid. Marine terraces on Santa Cruz Island have
Authors
Daniel R. Muhs, R. Randall Schumann, Lindsey T. Groves, Kathleen R. Simmons, Christopher R. Florian

Physiomorphic transformation in extreme endurance migrants: Revisiting the case of bar-tailed godwits preparing for trans-pacific flights Physiomorphic transformation in extreme endurance migrants: Revisiting the case of bar-tailed godwits preparing for trans-pacific flights

In a 1998 paper entitled “Guts don’t fly: small digestive organs in obese bar-tailed godwits,” Piersma and Gill (1998) showed that the digestive organs were tiny and the fat loads huge in individuals suspected of embarking on a non-stop flight from Alaska to New Zealand. It was suggested that prior to migratory departure, these godwits would shrink the digestive organs used during fuel...
Authors
Theunis Piersma, Robert E. Gill, Daniel R. Ruthrauff

Assessment of a conservative mixing model for the evaluation of constituent behavior below river confluences, Elqui River Basin, Chile Assessment of a conservative mixing model for the evaluation of constituent behavior below river confluences, Elqui River Basin, Chile

Fate and transport modeling of water-borne contaminants is a data demanding and costly endeavor, requiring considerable expes such, it becomes important to know when a complex modeling approach is required, and when a simpler approach is adequate. This is the main objective herein, where a conservative mixing model is used to characterize the transport of As, Cu, Fe, and SO4. The study...
Authors
Catalina Rossi, Jorge Oyarzun, Pablo Pasten, Robert L. Runkel, Jorge Núñez, Denisse Duhalde, Hugo Maturana, Eduardo Rojas, José L. Arumí, Daniela Castillo, Ricardo Oyarzun
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