Watershed-scale changes in terrestrial nitrogen cycling during a period of decreased atmospheric nitrate and sulfur deposition
Robert D. Sabo, Sara E. Scanga, Gregory B. Lawrence, David M. Nelson, Keith N. Eshleman, Gabriel A. Zabala, Alexandria A. Alinea, Charles D. Schirmer
2016, Atmospheric Environment (146) 271-279
Recent reports suggest that decreases in atmospheric nitrogen (N) deposition throughout Europe and North America may have resulted in declining nitrate export in surface waters in recent decades, yet it is unknown if and how terrestrial N cycling was affected. During a period of decreased atmospheric N deposition, we assessed...
An overview of environmental impacts and reclamation efforts at the Iron Mountain mine, Shasta County, California
James A Jacobs, Stephen M. Testa, Charles N. Alpers, D. Kirk Nordstrom
2016, Book chapter, Applied geology in California
No abstract available ...
Origin and identity of Fejervarya (Anura: Dicroglossidae) on Guam
Elijah Wostl, Eric N. Smith, Robert Reed
2016, Pacific Science (70) 233-241
We used morphological and molecular data to infer the identity and origin of frogs in the genus Fejervarya that have been introduced to the island of Guam. Mensural and meristic data were collected from 96 specimens from throughout their range on the island and a principal component analysis was used...
Dissolved oxygen: Chapter 6
David Senn, Maureen A. Downing-Kunz, Emily Novick
2016, Report, Lower South Bay nutrient synthesis
Dissolved oxygen (DO) concentration serves as an important indicator of estuarine habitat condition, because all aquatic macro-organisms require some minimum DO level to survive and prosper. The instantaneous DO concentration, measured at a specific location in the water column, results from a balance between multiple processes that add or remove...
Viral lysis of photosynthesizing microbes as a mechanism for calcium carbonate nucleation in seawater
John T. Lisle, Lisa L. Robbins
2016, Frontiers in Microbiology (7)
Removal of carbon through the precipitation and burial of calcium carbonate in marine sediments constitutes over 70% of the total carbon on Earth and is partitioned between coastal and pelagic zones. The precipitation of authigenic calcium carbonate in seawater, however, has been hotly debated because despite being in a supersaturated...
Comparative mitogenomic analyses of three North American stygobiont amphipods of the genus Stygobromus (Crustacea: Amphipoda)
Aaron W. Aunins, David L. Nelms, Christopher S. Hobson, Tim L. King
2016, Mitochondrial DNA Part B (1) 560-563
The mitochondrial genomes of three North American stygobiont amphipods Stygobromus tenuis potomacus, S. foliatus and S. indentatus collected from Caroline County, VA, were sequenced using a shotgun sequencing approach on an Illumina NextSeq500 (Illumina Inc., San Diego, CA). All three mitogenomes displayed 13 protein-coding genes, 22 tRNAs and two rRNAs typical of metazoans. While S. tenuis and S....
Consequences of seasonal variation in reservoir water level for predatory fishes: linking visual foraging and prey densities
Stephen L. Klobucar, Phaedra E. Budy
2016, Canadian Journal of Fisheries and Aquatic Sciences (73) 53-64
In reservoirs, seasonal drawdown can alter the physical environment and may influence predatory fish performance. We investigated the performance of lake trout (Salvelinus namaycush) in a western reservoir by coupling field measurements with visual foraging and bioenergetic models at four distinct states (early summer, mid-summer, late summer, and fall). The...
Hydrologic effects on diameter growth phenology for Celtis laevigata and Quercus lyrata in the floodplain of the lower White River, Arkansas
Scott T. Allen, Wesley Cochran, Ken W. Krauss, Richard F. Keim, Sammy L. King
Callie Jo Schweitzer, Wayne K. Clatterbuck, Christopher M. Oswalt, editor(s)
2016, Conference Paper, Proceedings of the 18th Biennial Southern Silvicultural Research Conference: USDA Forest Service General Technical Report SRS-212
Bottomland hardwood (BLH) forests represent an extensive wetland system in the Mississippi Alluvial Valley and southeastern USA, and it is currently undergoing widespread transition in species composition. One such transition involves increased establishment of sugarberry (Celtis laevigata), and decreased establishment of overcup oak (Quercus lyrata). The ecological mechanisms that control...
A strategy for low cost development of incremental oil in legacy reservoirs
Emil Attanasi
2016, Conference Paper, Proceedings of the SPE/IAEE hydrocarbon economics and evaluation symposium 2016
The precipitous decline in oil prices during 2015 has forced operators to search for ways to develop low-cost and low-risk oil reserves. This study examines strategies to low cost development of legacy reservoirs, particularly those which have already implemented a carbon dioxide enhanced oil recovery (CO2 EOR) program. Initially the...
Early Mesozoic geology in Virginia
Joseph P. Smoot
Christopher M. Bailey, W. Cullen Sherwood, L. Scott Eaton, David S. Powars, editor(s)
2016, Book chapter, The geology of Virginia (Virginia Museum of Natural History Special Publication 18)
No abstract available....
The biogeography of threatened insular iguanas and opportunities for invasive vertebrate management
Bernie R. Tershy, Kelly M. Newton, Dena R. Spatz, Kirsty Swinnerton, John B. Iverson, Robert N. Fisher, Peter S. Harlow, Nick D. Holmes, Donald A. Croll
J. B. Iverson, T. D. Grant, C. R. Knapp, S. A. Pasachnik, editor(s)
2016, Book chapter, Iguanas: Biology, Systematics, and Conservation: Herpetological Conservation and Biology 11(Monograph 6)
Iguanas are a particularly threatened group of reptiles, with 61% of species at risk of extinction. Primary threats to iguanas include habitat loss, direct and indirect impacts by invasive vertebrates, overexploitation, and human disturbance. As conspicuous, charismatic vertebrates, iguanas also represent excellent flagships for biodiversity conservation. To assist planning for...
Consistent and efficient processing of ADCP streamflow measurements
David S. Mueller
George Constantinescu, Marcelo H. Garcia, Dan Hanes, editor(s)
2016, Conference Paper, River Flow 2016: Proceedings of the international conference on fluvial hydraulics
The use of Acoustic Doppler Current Profilers (ADCPs) from a moving boat is a commonly used method for measuring streamflow. Currently, the algorithms used to compute the average depth, compute edge discharge, identify invalid data, and estimate velocity and discharge for invalid data vary among manufacturers. These differences could result...
Rapid environmental change drives increased land use by an Arctic marine predator
Todd C. Atwood, Elizabeth L. Peacock, Melissa A. McKinney, Kate Lillie, Ryan H. Wilson, David C. Douglas, Pat Terletzky, Susanne Miller
2016, PLoS ONE (6)
In the Arctic Ocean’s southern Beaufort Sea (SB), the length of the sea ice melt season (i.e., period between the onset of sea ice break-up in summer and freeze-up in fall) has increased substantially since the late 1990s. Historically, polar bears (Ursus maritimus) of the SB have mostly remained on...
Rating curve uncertainty: A comparison of estimation methods
Mason Jr., Julie E. Kiang, Timothy A. Cohn
George Constantinescu, Marcelo H. Garcia, Dan Hanes, editor(s)
2016, Conference Paper, Proceedings of the international conference on fluvial hydraulics (river flow 2016)
The USGS is engaged in both internal development and collaborative efforts to evaluate existing methods for characterizing the uncertainty of streamflow measurements (gaugings), stage-discharge relations (ratings), and, ultimately, the streamflow records derived from them. This paper provides a brief overview of two candidate methods that may be used to characterize...
The story of rising voices: Facilitating collaboration between indigenous and western ways of knowing
Julie Maldonado, Heather Lazrus, Shiloh-Kay Bennett, Karletta Chief, Carla May Dhillon, Bob Gough, Linda Kruger, Jeffrey T. Morisette, Stefan Petrovic, Kyle P. Whyte
Michele Companion, Miriam S. Chaiken, editor(s)
2016, Book chapter, Responses to disasters and climate change: Understanding vulnerability and fostering resilience
Indigenous community self-determination, cultures, and ways of life are at high risk from climate change impacts and ecological dispossession. Partnerships between experts with backgrounds in Indigenous and western knowledge may be productive and effective ways to reduce vulnerability and foster resilience. This chapter examines collaborations among scientific and Native American,...
Forest structure of oak plantations after silvicultural treatment to enhance habitat for wildlife
Daniel J. Twedt, Cherrie-Lee P. Phillip, Michael P. Guilfoyle, R. Randy Wilson
Callie Jo Schweitzer, Wayne K. Clatterbuck, Christopher M. Oswalt, editor(s)
2016, Conference Paper, Proceedings of the 18th Biennial Southern Silvicultural Research Conference
During the past 30 years, thousands of hectares of oak-dominated bottomland hardwood plantations have been planted on agricultural fields in the Mississippi Alluvial Valley. Many of these plantations now have closed canopies and sparse understories. Silvicultural treatments could create a more heterogeneous forest structure, with canopy gaps and...
Fire as an ecosystem process: Chapter 3
Jon E. Keeley, Hugh D. Safford
Harold A. Mooney, Erika S. Zavaleta, editor(s)
2016, Book chapter, Ecosystems of California
This long-anticipated reference and sourcebook for California’s remarkable ecological abundance provides an integrated assessment of each major ecosystem type—its distribution, structure, function, and management. A comprehensive synthesis of our knowledge about this biologically diverse state, Ecosystems of California covers the state from oceans to mountaintops using multiple lenses: past and...
Integrated groundwater data management
Peter Fitch, Boyan Brodaric, Matt Stenson, Nathaniel Booth
Anthony J. Jakeman, Olivier Barreteau, Randall J. Hunt, Jean-Daniel Rinaudo, Andrew Ross, editor(s)
2016, Book chapter, Integrated groundwater management
The goal of a data manager is to ensure that data is safely stored, adequately described, discoverable and easily accessible. However, to keep pace with the evolution of groundwater studies in the last decade, the associated data and data management requirements have changed significantly. In particular, there is a growing...
Science framework for the conservation and restoration strategy of DOI secretarial order 3336: Utilizing resilience and resistance concepts to assess threats to sagebrush ecosystems and greater sage-grouse, prioritize conservation and restoration actions, and inform management strategies
Jeanne C. Chambers, Steve Campbell, John Carlson, Jeffrey L. Beck, Karen J. Clause, Jonathan B. Dinkins, Kevin E. Doherty, Shawn Espinosa, Kathleen A. Griffin, Thomas J. Christiansen, Michele R. Crist, Steve E. Hanser, Douglas W. Havlina, Kenneth F. Henke, Jacob D. Hennig, Laurie L. Kurth, Jeremy D. Maestas, Kenneth E. Mayer, Mary E. Manning, Brian A. Mealor, Clinton McCarthy, Mike Pellant, Karen L. Prentice, Marco A. Perea, Lief A. Wiechman, David A. Pyke, Amarina Wuenschel
2016, Report
The Science Framework for the Conservation and Restoration Strategy of the Department of the Interior, Secretarial Order 3336 (SO 3336), Rangeland Fire Prevention, Management and Restoration, provides a strategic, multiscale approach for prioritizing areas for management and determining effective management strategies across the sagebrush biome. The emphasis of this version...
By-products of porphyry copper and molybdenum deposits
David A. John, Ryan D. Taylor
Philip L. Verplanck, Murray W. Hitzman, editor(s)
2016, Book chapter, Rare earth and critical elements in ore deposits
Porphyry Cu and porphyry Mo deposits are large to giant deposits ranging up to >20 and 1.6 Gt of ore, respectively, that supply about 60 and 95% of the world’s copper and molybdenum, as well as significant amounts of gold and silver. These deposits form from hydrothermal systems that affect...
Addressing potential local adaptation in species distribution models: implications for conservation under climate change
Maria Helena Hallfors, Jishan Liao, Jason D. K. Dzurisin, Ralph Grundel, Marko Hyvarinen, Kevin Towle, Grace C. Wu, Jessica J. Hellmann
2016, Ecological Applications (26) 1154-1169
Species distribution models (SDMs) have been criticized for involving assumptions that ignore or categorize many ecologically relevant factors such as dispersal ability and biotic interactions. Another potential source of model error is the assumption that species are ecologically uniform in their climatic tolerances across their range. Typically, SDMs to treat...
Female sea lamprey shift orientation toward a conspecific chemical cue to escape a sensory trap
Cory O. Brant, Nicholas S. Johnson, Ke Li, Tyler J. Buchinger, Weiming Li
2016, Behavioral Ecology (27) 810-819
The sensory trap model of signal evolution hypothesizes that signalers adapt to exploit a cue used by the receiver in another context. Although exploitation of receiver biases can result in conflict between the sexes, deceptive signaling systems that are mutually beneficial drive the evolution of stable communication systems. However, female...
Water-quality effects on phytoplankton species and density and trophic state indices at Big Base and Little Base Lakes, Little Rock Air Force Base, Arkansas, June through August, 2015
Lucas Driver, Billy Justus
2016, Journal of the Arkansas Academy of Science (70) 88-95
Big Base and Little Base Lakes are located on Little Rock Air Force Base, Arkansas, and their close proximity to a dense residential population and an active military/aircraft installation make the lakes vulnerable to water-quality degradation. The U.S. Geological Survey (USGS) conducted a study from June through August 2015 to investigate the effects of water quality on...
Water-quality response to a high-elevation wildfire in the Colorado Front Range
M. Alisa Mast, Sheila F. Murphy, David W. Clow, Colin A. Penn, Graham A. Sexstone
2016, Hydrological Processes (30) 1811-1823
Water quality of the Big Thompson River in the Front Range of Colorado was studied for 2 years following a high‐elevation wildfire that started in October 2012 and burned 15% of the watershed. A combination of fixed‐interval sampling and continuous water‐quality monitors was used to examine the timing and magnitude of...
Evolution of mid-Atlantic coastal and back-barrier estuary environments in response to a hurricane: Implications for barrier-estuary connectivity
Jennifer L. Miselis, Brian D. Andrews, Robert S. Nicholson, Zafer Defne, Neil K. Ganju, Anthony S. Navoy
2016, Estuaries and Coasts (39) 916-934
Assessments of coupled barrier island-estuary storm response are rare. Hurricane Sandy made landfall during an investigation in Barnegat Bay-Little Egg Harbor estuary that included water quality monitoring, geomorphologic characterization, and numerical modeling; this provided an opportunity to characterize the storm response of the barrier island-estuary system. Barrier island morphologic response...