Threshold amounts of organic carbon needed to initiate reductive dechlorination in groundwater systems
Francis H. Chapelle, Lashun K. Thomas, Paul M. Bradley, Heather V. Rectanus, Mark A. Widdowson
2012, Remediation Journal (22) 19-28
Aquifer sediment and groundwater chemistry data from 15 Department of Defense facilities located throughout the United States were collected and analyzed with the goal of estimating the amount of natural organic carbon needed to initiate reductive dechlorination in groundwater systems. Aquifer sediments were analyzed for hydroxylamine and NaOH-extractable organic carbon,...
Adult tree swallow survival on the polychlorinated biphenyl-contaminated Hudson River, New York, USA, between 2006 and 2010
Christine M. Custer, Thomas W. Custer, James E. Hines
2012, Environmental Toxicology and Chemistry (31) 1788-1792
The upper Hudson River basin in east central New York, USA, is highly contaminated, primarily with polychlorinated biphenyls (PCBs). Reduced adult survival has been documented in tree swallows (Tachycineta bicolor) at a similarly PCB-contaminated river system in western Massachusetts. The purpose of the present study was to assess whether adult...
Searching for evidence of hydrothermal activity at Apollinaris Mons, Mars
M. Ramy El Maarry, James M. Dohm, Giuseppe A. Marzo, Robin Fergason, Walter Goetz, Essam Heggy, Andreas Pack, Wojciech J. Markiewicz
2012, Icarus (217) 297-314
A multidisciplinary approach involving various remote sensing instruments is used to investigate Apollinaris Mons, a prominent volcano on Mars, as well as the surrounding plains for signs of prolonged hydrologic and volcanic, and possibly hydrothermal activity. The main findings include (1) evidence from laser altimetry indicating the large thickness...
The influence of external subsidies on diet, growth and Hg concentrations of freshwater sport fish: implications for management and fish consumption advisories
J.M. Lepak, M.B. Hooten, B. M. Johnson
2012, Ecotoxicology (21) 1878-1888
Mercury (Hg) contamination in sport fish is a global problem. In freshwater systems, food web structure, sport fish sex, size, diet and growth rates influence Hg bioaccumulation. Fish stocking is a common management practice worldwide that can introduce external energy and contaminants into freshwater systems. Thus, stocking can alter many...
Volatilization of polycyclic aromatic hydrocarbons from coal-tar-sealed pavement
Peter C. Van Metre, Michael S. Majewski, Barbara Mahler, William T. Foreman, Christopher L. Braun, Jennifer T. Wilson, Teresa L. Burbank
2012, Chemosphere (88) 1-7
Coal-tar-based pavement sealants, a major source of PAHs to urban water bodies, are a potential source of volatile PAHs to the atmosphere. An initial assessment of volatilization of PAHs from coal-tar-sealed pavement is presented here in which we measured summertime gas-phase PAH concentrations 0.03 m and 1.28 m above the...
Leptophis santamartensis (Serpentes, Colubridae), a junior synonym of Leptophis ahaetulla occidentalis
Nelson R. Albuquerque, Paulo de Passos, Steve W. Gotte
2012, Journal of Herpetology (46) 248-252
Leptophis santamartensis, known only from Sierra Nevada de Santa Marta, Colombia, is one of the more poorly known species of the genus Leptophis. The characters used for its diagnosis largely overlap with those of other Leptophis, mainly with Leptophis ahaetulla occidentalis, the only other Leptophis known to occur in the...
Relative value of managed wetlands and tidal marshlands for wintering northern pintails
Peter S. Coates, Michael L. Casazza, Brian J. Halstead, Joseph P. Fleskes
2012, Journal of Fish and Wildlife Management (3) 98-109
Northern pintail Anas acuta (hereafter, pintail) populations have declined substantially throughout the western US since the 1970s, largely as a result of converting wetlands to cropland. Managed wetlands have been developed throughout the San Francisco Bay estuaries to provide wildlife habitat, particularly for waterfowl. Many of these areas were historically...
Assessment of environments for Mars Science Laboratory entry, descent, and surface operations
Ashwin R. Vasavada, Allen Chen, Jeffrey R. Barnes, P. Daniel Burkhart, Bruce A. Cantor, Alicia M. Dwyer-Cianciolo, Robini L. Fergason, David P. Hinson, Hilary L. Justh, David M. Kass, Stephen R. Lewis, Michael A. Mischna, James R. Murphy, Scot C.R. Rafkin, Daniel Tyler, Paul G. Withers
2012, Space Science Reviews (170) 793-835
The Mars Science Laboratory mission aims to land a car-sized rover on Mars' surface and operate it for at least one Mars year in order to assess whether its field area was ever capable of supporting microbial life. Here we describe the approach used to identify, characterize, and assess environmental...
Perils of categorical thinking: "Oxic/anoxic" conceptual model in environmental remediation
Paul M. Bradley
2012, Remediation Journal (22) 9-18
Given ambient atmospheric oxygen concentrations of about 21 percent (by volume), the lower limit for reliable quantitation of dissolved oxygen concentrations in groundwater samples is in the range of 0.1–0.5 mg/L. Frameworks for assessing in situ redox condition are often applied using a simple two-category (oxic/anoxic) model of oxygen condition....
Population dynamics of Hawaiian seabird colonies vulnerable to sea-level rise
Jeff S. Hatfield, Michelle H. Reynolds, Nathaniel E. Seavy, Crystal M. Krause
2012, Conservation Biology (26) 667-678
Globally, seabirds are vulnerable to anthropogenic threats both at sea and on land. Seabirds typically nest colonially and show strong fidelity to natal colonies, and such colonies on low-lying islands may be threatened by sea-level rise. We used French Frigate Shoals, the largest atoll in the Hawaiian Archipelago, as a...
Evidence, models, conservation programs and limits to management
J.D. Nichols
2012, Animal Conservation (15) 331-333
Walsh et al. (2012) emphasized the importance of obtaining evidence to assess the effects of management actions on state variables relevant to objectives of conservation programs. They focused on malleefowl Leipoa ocellata, ground-dwelling Australian megapodes listed as vulnerable. They noted that although fox Vulpes vulpes baiting is the main management...
Variation in migratory behavior influences regional genetic diversity and structure among American kestrel populations (Falco sparverius) in North America
Mark P. Miller, Thomas D. Mullins, John G. Parrish, Jeffrey R. Walters, Susan M. Haig
2012, Journal of Heredity (103) 503-514
Birds employ numerous strategies to cope with seasonal fluctuations in high-quality habitat availability. Long distance migration is a common tactic; however, partial migration is especially common among broadly distributed species. Under partial migration systems, a portion of a species migrates, whereas the remainder inhabits breeding grounds year round. In this...
The paradox of cooling streams in a warming world: Regional climate trends do not parallel variable local trends in stream temperature in the Pacific continental United States
Ivan Arismendi, Sherri Johnson, Jason B. Dunham, Roy Haggerty, David Hockman-Wert
2012, Geophysical Research Letters (39)
Temperature is a fundamentally important driver of ecosystem processes in streams. Recent warming of terrestrial climates around the globe has motivated concern about consequent increases in stream temperature. More specifically, observed trends of increasing air temperature and declining stream flow are widely believed to result in corresponding increases in stream...
The early bird gets the shrimp: Confronting assumptions of isotopic equilibrium and homogeneity in a wild bird population
Michael B. Wunder, Joseph R. Jehl Jr., Craig A. Stricker
2012, Journal of Animal Ecology (81) 1223-1232
1. Because stable isotope distributions in organic material vary systematically across energy gradients that exist in ecosystems, community and population structures, and in individual physiological systems, isotope values in animal tissues have helped address a broad range of questions in animal ecology. It follows that every tissue sample provides an...
Benthic foraminiferal census data from Mobile Bay, Alabama--counts of surface samples and box cores
Kathryn A. Richwine, Lisa E. Osterman
2012, Data Series 704
A study was undertaken in order to understand recent environmental change in Mobile Bay, Alabama. For this study a series of surface sediment and box core samples was collected. The surface benthic foraminiferal data provide the modern baseline conditions of the bay and can be used as a reference for...
Baseline for beached marine debris on Sand Island, Midway Atoll
Christine Ribic, Seba B. Sheavly, John Klavitter
2012, Marine Pollution Bulletin (64) 1726-1729
Baseline measurements were made of the amount and weight of beached marine debris on Sand Island, Midway Atoll, June 2008–July 2010. On 23 surveys, 32,696 total debris objects (identifiable items and pieces) were collected; total weight was 740.4 kg. Seventy-two percent of the total was pieces;...
Toxicity of elevated partial pressures of carbon dioxide to invasive New Zealand mudsnails
R. Jordan Nielson, Christine M. Moffitt, Barnaby J. Watten
2012, Environmental Toxicology and Chemistry (31) 1838-1842
The authors tested the efficacy of elevated partial pressures of CO2 to kill invasive New Zealand mudsnails. The New Zealand mudsnails were exposed to 100 kPa at three water temperatures, and the survival was modeled versus dose as cumulative °C-h. We estimated an LD50 of 59.4°C-h for adult and juvenile...
Source rock contributions to the Lower Cretaceous heavy oil accumulations in Alberta: a basin modeling study
Luiyin Alejandro Berbesi, Rolando di Primio, Zahie Anka, Brian Horsfield, Debra K. Higley
2012, American Association of Petroleum Geologists Bulletin (96) 1211-1234
The origin of the immense oil sand deposits in Lower Cretaceous reservoirs of the Western Canada sedimentary basin is still a matter of debate, specifically with respect to the original in-place volumes and contributing source rocks. In this study, the contributions from the main source rocks were addressed using a...
Early retreat of the Alaska Peninsula Glacier Complex and the implications for coastal migrations of First Americans
Nicole Misarti, Bruce P. Finney, James W. Jordan, Herbert D. G. Maschner, Jason A. Addison, Mark D. Shapley, Andrea P. Krumhardt, James E. Beget
2012, Quaternary Science Reviews (48) 1-6
The debate over a coastal migration route for the First Americans revolves around two major points: seafaring technology, and a viable landscape and resource base. Three lake cores from Sanak Island in the western Gulf of Alaska yield the first radiocarbon ages from the continental shelf of the Northeast Pacific...
Transport of biologically important nutrients by wind in an eroding cold desert
Joel B. Sankey, Matthew J. Germino, Shawn G. Benner, Nancy F. Glenn, Amber N. Hoover
2012, Aeolian Research (7) 17-27
Wind erosion following fire is an important landscape process that can result in the redistribution of ecologically important soil resources. In this study we evaluated the potential for a fire patch in a desert shrubland to serve as a source of biologically important nutrients to the adjacent, downwind, unburned ecosystem....
Estimating abundance of mountain lions from unstructured spatial sampling
Robin E. Russell, J. Andrew Royle, Richard Desimone, Michael K. Schwartz, Victoria L. Edwards, Kristy P. Pilgrim, Kevin S. Mckelvey
2012, Journal of Wildlife Management (76) 1551-1561
Mountain lions (Puma concolor) are often difficult to monitor because of their low capture probabilities, extensive movements, and large territories. Methods for estimating the abundance of this species are needed to assess population status, determine harvest levels, evaluate the impacts of management actions on populations, and derive conservation and management...
Subducting plate geology in three great earthquake ruptures of the western Alaska margin, Kodiak to Unimak
Roland E. von Huene, John J. Miller, Wilhelm Weinrebe
2012, Geosphere (8) 628-644
Three destructive earthquakes along the Alaska subduction zone sourced transoceanic tsunamis during the past 70 years. Since it is reasoned that past rupture areas might again source tsunamis in the future, we studied potential asperities and barriers in the subduction zone by examining Quaternary Gulf of Alaska plate history, geophysical...
Surface properties of the Mars Science Laboratory candidate landing sites: characterization from orbit and predictions
R.L. Fergason, P. R. Christensen, M.P. Golombek, T. J. Parker
2012, Space Science Reviews (170) 739-773
This work describes the interpretation of THEMIS-derived thermal inertia data at the Eberswalde, Gale, Holden, and Mawrth Vallis Mars Science Laboratory (MSL) candidate landing sites and determines how thermophysical variations correspond to morphology and, when apparent, mineralogical diversity. At Eberswalde, the proportion of likely unconsolidated material relative to exposed bedrock...
The next Landsat satellite: The Landsat Data Continuity Mission
James R. Irons, John L. Dwyer, Julia A. Barsi
2012, Remote Sensing of Environment (122) 11-21
The National Aeronautics and Space Administration (NASA) and the Department of Interior United States Geological Survey (USGS) are developing the successor mission to Landsat 7 that is currently known as the Landsat Data Continuity Mission (LDCM). NASA is responsible for building and launching the LDCM satellite observatory. USGS is building...
Dissolved and colloidal trace elements in the Mississippi River Delta outflow after Hurricanes Katrina and Rita
Moo-Joon Shim, Peter W. Swarzenski, Alan M. Shiller
2012, Continental Shelf Research (42) 1-9
The Mississippi River delta outflow region is periodically disturbed by tropical weather systems including major hurricanes, which can terminate seasonal bottom water hypoxia and cause the resuspension of shelf bottom sediments which could result in the injection of trace elements into the water column. In the summer of 2005, Hurricanes...
