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The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
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Early growth and ecophysiological responses of Koa (Acacia koa A. Gray) seedlings to reduced water and phosphorus Early growth and ecophysiological responses of Koa (Acacia koa A. Gray) seedlings to reduced water and phosphorus
Sites in need of restoration typically have one or more environmental factors that limit seedling establishment. Identifying ecophysiological responses to environmental stressors can provide important insights into mitigating measures that would allow seedlings to overcome such constraints to survival. Koa (Acacia koa A. Gray) is a nitrogen-fixing tree species endemic to Hawaiʻi that is...
Authors
Kaitlin Gerber, Amy Ross-Davis, Steven S. Perakis, Anthony S. Davis
Data management and interactive visualizations for the evolving marine biodiversity observation network Data management and interactive visualizations for the evolving marine biodiversity observation network
Assessing the current state of and predicting change in the ocean’s biological and ecosystem resources requires observations and research to safeguard these valuable public assets. The Marine Biodiversity Observation Network (MBON) partnered with the Global Ocean Observing System Biology and Ecosystems Panel and the Ocean Biodiversity Information System to address these needs through...
Authors
Abigail Benson, Tylar Murray, Gabrielle Canonico, Enrique Montes, Frank Muller-Karger, Maria T. Kavanaugh, Joaquin Trinanes, Lynn M. deWitt
An eddy-resolving numerical model to study turbulent flow, sediment and bed evolution using detached eddy simulation in a lateral separation zone at the field-scale An eddy-resolving numerical model to study turbulent flow, sediment and bed evolution using detached eddy simulation in a lateral separation zone at the field-scale
Turbulence-resolving simulations elucidate key elements of fluid dynamics and sediment transport in fluvial environments. This research presents a feasible strategy for applying state-of-the-art computational fluid mechanics to the study of sediment transport and morphodynamic processes in lateral separation zones, which are common features in canyon rivers where massive lateral flow...
Authors
Laura V. Alvarez, Paul E. Grams
Integrating seabird dietary and groundfish stock assessment data: Can puffins predict pollock spawning stock biomass in the North Pacific? Integrating seabird dietary and groundfish stock assessment data: Can puffins predict pollock spawning stock biomass in the North Pacific?
Information on the annual variability in abundance and growth of juvenile groundfish can be useful for predicting fisheries stocks, but is often poorly known owing to difficulties in sampling fish in their first year of life. In the Western Gulf of Alaska (WGoA) and Eastern Bering Sea (EBS) ecosystems, three species of puffin (tufted and horned puffin, Fratercula cirrhata, Fratercula...
Authors
William J. Sydeman, Sarah Ann Thompson, John F. Piatt, Stephani Zador, Martin W. Dorn
Assessment of multiple ecosystem metabolism methods in an estuary Assessment of multiple ecosystem metabolism methods in an estuary
Ecosystem metabolism is a key ecological attribute and easy to describe, but quantifying metabolism in estuaries is challenging. Properly scaling measurements through time and space requires consideration of hydrodynamics and mixing water from heterogeneous sources, making any estimation uncertain. Here, we compared three methods for modeling ecosystem metabolism in a portion of the...
Authors
Luke C. Loken, Erwin E Van Nieuwenhuyse, Randy A Dahlgren, Leah Kammel, Paul Stumpner, Jon R. Burau, Steven Sadro
Synchronous emplacement of the anorthosite xenolith-bearing Beaver River diabase and one of the largest lava flows on Earth Synchronous emplacement of the anorthosite xenolith-bearing Beaver River diabase and one of the largest lava flows on Earth
New geochronologic and paleomagnetic data from the North American Midcontinent Rift (MCR) reveal the synchronous emplacement of the Beaver River diabase, the anorthosite xenoliths within it, and the Greenstone Flow—one of the largest lava flows on Earth. A U-Pb zircon date of 1091.83 0.21 Ma (2) from one of the anorthosite xenoliths is consistent with the anorthosite cumulate forming as...
Authors
Yiming Zhang, Nicholas L. Swanson-Hysell, Mark D. Schmitz, James D. Miller, Margaret Susan Avery
First record of Najas marina (Hydrocharitaceae) for Montana and an update on the North American distribution First record of Najas marina (Hydrocharitaceae) for Montana and an update on the North American distribution
Three recent collections of Najas marina (spiny water-nymph) from Missoula County, Montana are documented and illustrated. These collections are the first records for Montana and for the Pacific Northwest region. The occurrence of N. marina in Montana reflects a significant northward expansion of this species in the Mountain West. The North American distribution of this species is also...
Authors
Scott L. Freeman, Ian Pfingsten
Rapid colonisation post-displacement contributes to native fish resilience Rapid colonisation post-displacement contributes to native fish resilience
Native freshwater fish are experiencing global declines. Determining what drives native fish resilience to disturbance is crucial to understanding their persistence in the face of multiple stressors. Fish colonisation ability may be one factor affecting population resilience after disturbance. We conducted displacement experiments in headwater streams in Wyoming, USA, to evaluate mottled...
Authors
Samantha L. Alford, Annika W. Walters
Isolating detrital and diagenetic signals in magnetic susceptibility records from methane-bearing marine sediments Isolating detrital and diagenetic signals in magnetic susceptibility records from methane-bearing marine sediments
Volume-dependent magnetic susceptibility (κ) is commonly used for paleoenvironmental reconstructions in both terrestrial and marine sedimentary environments where it reflects a mixed signal between primary deposition and secondary diagenesis. In the marine environment, κ is strongly influenced by the abundance of ferrimagnetic minerals regulated by sediment transport processes. Post...
Authors
Joel P. L. Johnson, Stephen C. Phillips, William Clyde, Liviu Giosan, Marta E. Torres
Modeling watershed carbon dynamics as affected by land cover change and soil erosion Modeling watershed carbon dynamics as affected by land cover change and soil erosion
Process-based ecosystem carbon cycle models typically incorporate vegetation growth, vegetation mortality, and soil respiration as well as the biotic and environmental drivers that influence these variables. However, few spatially explicit process models can efficiently incorporate the influence of land cover change and carbon lateral movement at regional scales or high spatial...
Authors
Jinxun Liu, Benjamin M. Sleeter, Paul C. Selmants, Jiaojiao Diao, Qiang Zhou, Bruce Worstell, Monica Mei Jeen Moritsch
Foraging behavior in a generalist snake (brown treesnake, Boiga irregularis) with implications for avian reintroduction and recovery Foraging behavior in a generalist snake (brown treesnake, Boiga irregularis) with implications for avian reintroduction and recovery
Broad foraging classifications, such as generalist or specialist forager, are generally beneficial for population management in defining expectations of typical behavior. However, better understanding as to how individual variance in behavior interfaces with management actions, such as control of an invasive predator (such as brown treesnakes; Boiga irregularis) responsible for...
Authors
Melia G. Nafus, Peter X. Xiong, Eben H. Paxton, Amy A. Yackel Adams, Scott Michael Goetz
Impacts of neonicotinoid seed treatments on the wild bee community in agricultural field margins Impacts of neonicotinoid seed treatments on the wild bee community in agricultural field margins
Wild bees support global agroecosystems via pollination of agricultural crops and maintaining diverse plant communities. However, with an increased reliance on pesticides to enhance crop production, wild bee communities may inadvertently be affected through exposure to chemical residues. Laboratory and semi-field studies have demonstrated lethal and sublethal effects of neonicotinoids on...
Authors
Anson R. Main, Elisabeth B. Webb, Keith W. Goyne, Robert Abney, Doreen C. Mengel