Nitrate removal in deep sediments of a nitrogen-rich river network: A test of a conceptual model
Robert S. Stelzer, Lynn Bartsch
2012, Journal of Geophysical Research: Biogeosciences (117)
Many estimates of nitrogen removal in streams and watersheds do not include or account for nitrate removal in deep sediments, particularly in gaining streams. We developed and tested a conceptual model for nitrate removal in deep sediments in a nitrogen-rich river network. The model predicts that oxic, nitrate-rich groundwater will...
Advances in spectroscopic methods for quantifying soil carbon
James B. Reeves III, Gregory W. McCarty, Francisco Calderon, W. Dean Hively
2012, Book chapter, Managing agricultural greenhouse gases
The current gold standard for soil carbon (C) determination is elemental C analysis using dry combustion. However, this method requires expensive consumables, is limited by the number of samples that can be processed (~100/d), and is restricted to the determination of total carbon. With increased interest in soil C sequestration,...
Estimating westslope cutthroat trout (Oncorhynchus clarkii lewisi) movements in a river network using strontium isoscapes
Clint C. Muhlfeld, Simon R. Thorrold, Thomas E. McMahon, Brian Marotz
2012, Canadian Journal of Fisheries and Aquatic Sciences (69) 906-915
We used natural variation in the strontium concentration (Sr:Ca) and isotope composition (87Sr:86Sr) of stream waters and corresponding values recorded in otoliths of westslope cutthroat trout (Oncorhynchus clarkii lewisi) to examine movements during their life history in a large river network. We found significant spatial differences in Sr:Ca and 87Sr:86Sr values...
Spatio-temporal variations in age structures of a partially re-established population of northern river otters (Lontra canadensis)
Dominic A. Barrett, David M. Leslie Jr.
2012, American Midland Naturalist (168) 302-314
Examination of age structures and sex ratios is useful in the management of northern river otters (Lontra canadensis) and other furbearers. Reintroductions and subsequent recolonizations of river otters have been well documented, but changes in demographics between expanding and established populations have not been observed. As a result of reintroduction...
Coastal impacts, adaptation, and vulnerabilities: a technical input to the 2013 National Climate Assessment
Virginia Burkett, Margaret Davidson
Virginia Burkett, Margaret Davidson, editor(s)
2012, Book, National Climate Assessment regional technical input reports
The coast has long provided communities with a multitude of benefits including an abundance of natural resources that sustain economies, societies, and ecosystems. Coasts provide natural harbors for commerce, trade, and transportation; beaches and shorelines that attract residents and tourists; and wetlands and estuaries that are critical for fisheries and...
Endangered river fish: factors hindering conservation and restoration
Steven J. Cooke, Craig P. Paukert, Zeb Hogan
2012, Endangered Species Research (17) 179-191
Globally, riverine fish face many anthropogenic threats including riparian and flood plain habitat degradation, altered hydrology, migration barriers, fisheries exploitation, environmental (climate) change, and introduction of invasive species. Collectively, these threats have made riverine fishes some of the most threatened taxa on the planet. Although much effort has been devoted...
Extreme events, trends, and variability in Northern Hemisphere lake-ice phenology (1855-2005)
Barbara J. Benson, John J. Magnuson, Olaf P. Jensen, Virginia M. Card, Glenn Hodgkins, Johanna Korhonen, David M. Livingstone, Kenton M. Stewart, Gesa A. Weyhenmeyer, Nick G. Granin
2012, Climatic Change (112) 299-323
Often extreme events, more than changes in mean conditions, have the greatest impact on the environment and human well-being. Here we examine changes in the occurrence of extremes in the timing of the annual formation and disappearance of lake ice in the Northern Hemisphere. Both changes in the mean condition...
Structure, spectroscopy and dynamics of layered H2O and CO2 ices
Lee. Myung Won, Nuria Plattner, Markus Meuwly
2012, Physical Chemistry Chemical Physics (14) 15464-15474
Molecular dynamics simulations of structural, spectroscopic and dynamical properties of mixed water–carbon dioxide (H2O–CO2) ices are discussed over temperature ranges relevant to atmospheric and astrophysical conditions. The simulations employ multipolar force fields to represent electrostatic interactions which are essential for spectroscopic and dynamical investigations. It is found that at the...
Introduction to phytoremediation of contaminated groundwater
James E. Landmeyer
2012, Book
This book provides the reader with the comprehensive view necessary to understand and critically evaluate the design, implementation, and monitoring of phytoremediation at sites characterized by contaminated groundwater. Part I presents the historical foundation of the interaction between plants and groundwater, introduces fundamental groundwater concepts for plant physiologists, and...
Assessment of freshwater fish assemblages and their habitats in the National Park Service system of the southeastern United States
James M. Long, Nathan P. Nibbelink, Kevin T. McAbee, Julie W. Stahli
2012, Fisheries (37) 212-225
The southeast region of the United States contains the highest diversity of freshwater fish species in the country: approximately 662 species. Existing protected areas like units of the National Park Service (NPS) should reflect this biodiversity, but there has been no broad-scale assessment. We compiled several data sets identifying native...
Well log characterization of natural gas-hydrates
Timothy S. Collett, Myung W. Lee
2012, Book
In the last 25 years there have been significant advancements in the use of well-logging tools to acquire detailed information on the occurrence of gas hydrates in nature: whereas wireline electrical resistivity and acoustic logs were formerly used to identify gas-hydrate occurrences in wells drilled in Arctic permafrost environments, more...
A fine-scale assessment of using barriers to conserve native stream salmonids: a case study in Akokala Creek, Glacier National Park, USA
Clint C. Muhlfeld, Vincent S. D'Angelo, S.T. Kalinowski, Erin L. Landguth, C.C. Downs, J. Tohtz, Jeffrey L. Kershner
2012, Open Fish Science Journal (5) 9-20
Biologists are often faced with the difficult decision in managing native salmonids of where and when to install barriers as a conservation action to prevent upstream invasion of nonnative fishes. However, fine-scale approaches to assess long-term persistence of populations within streams and watersheds chosen for isolation management are often lacking....
The Spar Lake strata-Bound Cu-Ag deposit formed across a mixing zone between trapped natural gas and metals-bearing brine
Timothy S. Hayes, Gary P. Landis, Joseph F. Whelan, Robert O. Rye, Richard J. Moscati
2012, Economic Geology (107) 1223-1249
Ore formation at the Spar Lake red bed-associated strata-bound Cu deposit took place across a mixing and reaction zone between a hot oxidized metals-transporting brine and a reservoir of “sour” (H2S-bearing) natural gas trapped in the host sandstones. Fluid inclusion volatile analyses have very high CH4 concentrations (≥1 mol %...
The effects of permafrost thaw on soil hydrologic, thermal, and carbon dynamics in an Alaskan peatland
Jonathan A. O’Donnell, M. Torre Jorgenson, Jennifer W. Harden, A. David McGuire, Mikhail Z. Kanevskiy, Kimberly P. Wickland
2012, Ecosystems (15) 213-229
Recent warming at high-latitudes has accelerated permafrost thaw in northern peatlands, and thaw can have profound effects on local hydrology and ecosystem carbon balance. To assess the impact of permafrost thaw on soil organic carbon (OC) dynamics, we measured soil hydrologic and thermal dynamics and soil OC stocks across a...
On modeling weak sinks in MODPATH
Daniel B. Abrams, Henk Haitjema, Leon J. Kauffman
2012, Ground Water (51) 597-602
Regional groundwater flow systems often contain both strong sinks and weak sinks. A strong sink extracts water from the entire aquifer depth, while a weak sink lets some water pass underneath or over the actual sink. The numerical groundwater flow model MODFLOW may allow a sink cell to act as...
Bacterial and enchytraeid abundance accelerate soil carbon turnover along a lowland vegetation gradient in interior Alaska
M. P. Waldrop, Jennifer W. Harden, M.R. Turetsky, D.G. Petersen, A. D. McGuire, M.J.I. Briones, Amber C. Churchill, D.H. Doctor, L.E. Pruett
2012, Soil Biology and Biochemistry (50) 188-198
Boreal wetlands are characterized by a mosaic of plant communities, including forests, shrublands, grasslands, and fens, which are structured largely by changes in topography and water table position. The soil associated with these plant communities contain quantitatively and qualitatively different forms of soil organic matter (SOM) and nutrient availability that...
Root zone water quality model (RZWQM2): Model use, calibration and validation
Liwang Ma, Lajpat Ahuja, B. T. Nolan, Robert Malone, Thomas Trout, Z. Qi
2012, Transactions of the ASABE (55) 1425-1446
The Root Zone Water Quality Model (RZWQM2) has been used widely for simulating agricultural management effects on crop production and soil and water quality. Although it is a one-dimensional model, it has many desirable features for the modeling community. This article outlines the principles of calibrating the model component by...
The current state of modeling
Randall J. Hunt, Chunmiao Zheng
2012, Ground Water (50) 329-333
No abstract available....
The science, information, and engineering needed to manage water availability and quality in 2050
Robert M. Hirsch
2012, Book chapter, Toward a sustainable water future: Visions for 2050
This chapter explores four water resources issues: 1) hydrologic variability, hazards, water supply and ecosystem preservation; 2) urban landscape design; 3) non-point source water quality, and 4) climate change, resiliency, and nonstationarity. It also considers what science, technology, and engineering practice may be needed in the coming decades to...
Near-surface, marine seismic-reflection data defines potential hydrogeologic confinement bypass in a tertiary carbonate aquifer, southeastern Florida
Kevin J. Cunningham, Cameron Walker, Richard L. Westcott
2012, SEG Technical Program Expanded Abstracts (2012) 1-6
Approximately 210 km of near-surface, high-frequency, marine seismic-reflection data were acquired on the southeastern part of the Florida Platform between 2007 and 2011. Many high-resolution, seismic-reflection profiles, interpretable to a depth of about 730 m, were collected on the shallow-marine shelf of southeastern Florida in water as shallow as 1...
An exploratory investigation of the landscape-lake interface: Land cover controls over consumer N and C isotopic composition in Lake Michigan rivermouths
James H. Larson, William B. Richardson, Jonathan M. Vallazza, J. C. Nelson
2012, Journal of Great Lakes Research (38) 610-619
Rivermouth ecosystems are areas where tributary waters mix with lentic near-shore waters and provide habitat for many Laurentian Great Lakes fish and wildlife species. Rivermouths are the interface between terrestrial activities that influence rivers and the ecologically important nearshore. Stable isotopes of nitrogen (N) and carbon (C) in consumers were...
The native Florida Green Watersnak, Nerodia floridana (Goff 1936) , preying upon the nonindigenous African Jewelfish, Hemichromis letourneuxi Sauvage 1880, in Florida.
Kenneth L. Krysko, Stephen J. Walsh, Robert H. Robins
2012, IRCF Reptiles & Amphibians (19) 161-162
No abstract available...
Synthesis of benthic flux components in the Patos Lagooncoastal zone, Rio Grande do Sul, Brazil
Jeffrey N. King
2012, Water Resources Research (48)
The primary objective of this work is to synthesize components of benthic flux in the Patos Lagoon coastal zone, Rio Grande do Sul, Brazil. Specifically, the component of benthic discharge flux forced by the terrestrial hydraulic gradient is 0.8 m3 d-1; components of benthic discharge and recharge flux associated with...
Sulfur, carbon, hydrogen, and oxygen isotope geochemistry of the Idaho cobalt belt
Craig A. Johnson, Arthur A. Bookstrom, John F. Slack
2012, Economic Geology (107) 1207-1221
Cobalt-copper ± gold deposits of the Idaho cobalt belt, including the deposits of the Blackbird district, have been analyzed for their sulfur, carbon, hydrogen, and oxygen isotope compositions to improve the understanding of ore formation. Previous genetic hypotheses have ranged widely, linking the ores to the sedimentary or diagenetic history...
Changing climate, changing forests: the impacts of climate change on forests of the northeastern United States and eastern Canada
Lindsey Rustad, John Campbell, Jeffrey S. Dukes, Thomas Huntington, Kathy Fallon Lambert, Jacqueline Mohan, Nicholas Rodenhouse
2012, General Technical Report NRS-99
Decades of study on climatic change and its direct and indirect effects on forest ecosystems provide important insights for forest science, management, and policy. A synthesis of recent research from the northeastern United States and eastern Canada shows that the climate of the region has become warmer and wetter over...
