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Structural geology of Amazonian-aged layered sedimentary deposits in southwest Candor Chasma, Mars
Chris Okubo
2010, Icarus (207) 210-225
The structural geology of an outcropping of layered sedimentary deposits in southwest Candor Chasma is mapped using two adjacent high-resolution (1 m/pixel) HiRISE digital elevation models and orthoimagery. Analysis of these structural data yields new insight into the depositional and deformational history of these deposits. Bedding in non-deformed areas generally...
Carbon and hydrogen isotopic reversals in deep basin gas: Evidence for limits to the stability of hydrocarbons
R.C. Burruss, C.D. Laughrey
2010, Organic Geochemistry (41) 1285-1296
During studies of unconventional natural gas reservoirs of Silurian and Ordovician age in the northern Appalachian basin we observed complete reversal of the normal trend of carbon isotopic composition, such that ??13C methane (C1) >??13C ethane (C2) >??13C propane (C3). In addition, we have observed isotopic reversals in the ??2H...
Comparison of transport and attachment behaviors of Cryptosporidium parvum oocysts and oocyst-sized microspheres being advected through three minerologically different granular porous media
Arvind Mohanram, Chittaranjan Ray, Ronald W. Harvey, David W. Metge, Joseph N. Ryan, Jon Chorover, D. D. Eberl
2010, Water Research (44) 5334-5344
In order to gain more information about the fate of Cryptosporidium parvum oocysts in tropical volcanic soils, the transport and attachment behaviors of oocysts and oocyst-sized polystyrene microspheres were studied in the presence of two soils. These soils were chosen because of their differing chemical and physical properties, i.e., an organic-rich (43–46%...
Identification of marine-derived lipids in juvenile coho salmon and aquatic insects through fatty acid analysis
Ron A. Heintz, Mark S. Wipfli, John P. Hudson
2010, Transactions of the American Fisheries Society (139) 840-854
The energetic benefits enjoyed by consumers in streams with salmon runs depend on how those benefits are accrued. Adult Pacific salmon Oncorhynchus spp. deliver significant amounts of nutrients (i.e., nitrogen and phosphorus) and carbon to streams when they spawn and die; these nutrient additions can have demonstrable effects on primary production in...
Molecular investigations into a globally important carbon pool: Permafrost-protected carbon in Alaskan soils
M. P. Waldrop, K.P. Wickland, Rickie White, A.A. Berhe, J.W. Harden, V.E. Romanovsky
2010, Global Change Biology (16) 2543-2554
The fate of carbon (C) contained within permafrost in boreal forest environments is an important consideration for the current and future carbon cycle as soils warm in northern latitudes. Currently, little is known about the microbiology or chemistry of permafrost soils that may affect its decomposition once soils thaw. We...
Testing the limits of Paleozoic chronostratigraphic correlation via high-resolution (<500 k.y.) integrated conodont, graptolite, and carbon isotope (δ13Ccarb) biochemostratigraphy across the Llandovery–Wenlock (Silurian) boundary: Is a unified Phanerozoic time scale achievable?
Bradley D. Cramer, David K. Loydell, Christian Samtleben, Axel Munnecke, Dimitri Kaljo, Peep Mannik, Tonu Martma, Lennart Jeppsson, Mark A. Kleffner, James E. Barrick, Craig A. Johnson, Poul Emsbo, Michael M. Joachimski, Torsten Bickert, Matthew R. Saltzman
2010, Geological Society of America Bulletin (122) 1700-1716
The resolution and fidelity of global chronostratigraphic correlation are direct functions of the time period under consideration. By virtue of deep-ocean cores and astrochronology, the Cenozoic and Mesozoic time scales carry error bars of a few thousand years (k.y.) to a few hundred k.y. In contrast, most of the Paleozoic...
Cyanotoxin mixtures and taste-and-odor compounds in cyanobacterial blooms from the midwestern united states
Jennifer L. Graham, Keith A. Loftin, Michael T. Meyer, Andrew C. Ziegler
2010, Environmental Science & Technology (44) 7361-7368
The mixtures of toxins and taste-and-odor compounds present during cyanobacterial blooms are not well characterized and of particular concern when evaluating potential human health risks. Cyanobacterial blooms were sampled in twenty-three Midwestern United States lakes and analyzed for community composition, thirteen cyanotoxins by liquid chromatography/mass spectrometry and immunoassay, and two...
Breeding biology of the golden-faced Tyrannulet (Zimmerius chrysops) in venezuela
W. Goulding, T. E. Martin
2010, Wilson Journal of Ornithology (122) 689-698
We present the first detailed information on the breeding biology of the Golden-faced Tyrannulet (Zimmerius chrysops). Information was gathered from 96 nests in Yacamb National Park, Venezuela during the 2002 to 2008 breeding seasons. The enclosed nest was similar to descriptions of nests of other species in the genus. Eggs...
Sensitivity of early life stages of freshwater mussels (Unionidae) to acute and chronic toxicity of lead, cadmium, and zinc in water
Ning Wang, Christopher G. Ingersoll, Chris D. Ivey, Douglas K. Hardesty, Thomas W. May, T. Augspurger, A.D. Roberts, E. Van Genderen, M.C. Barnhart
2010, Environmental Toxicology and Chemistry (29) 2053-2063
Toxicity of lead, cadmium, or zinc to early life stages of freshwater mussels (fatmucket, Lampsilis siliquoidea; Neosho mucket, L. rafinesqueana) was evaluated in 48‐h exposures with mussel larvae (glochidia), in 96‐h exposures with newly transformed (5‐d‐old) and two‐ or six‐month‐old juvenile mussels, or in 28‐d exposures with two‐ or four‐month‐old mussels in...
Restoring Ecological Function to a Submerged Salt Marsh
C.L. Stagg, I.A. Mendelssohn
2010, Restoration Ecology (18) 10-17
Impacts of global climate change, such as sea level rise and severe drought, have altered the hydrology of coastal salt marshes resulting in submergence and subsequent degradation of ecosystem function. A potential method of rehabilitating these systems is the addition of sediment-slurries to increase marsh surface elevation, thus ameliorating effects...
Comparing forest fragmentation and its drivers in China and the USA with Globcover v2.2
Mingshi Chen, Lijun Mao, Chunguo Zhou, James E. Vogelmann, Zhiliang Zhu
2010, Journal of Environmental Management (91) 2572-2580
Forest loss and fragmentation are of major concern to the international community, in large part because they impact so many important environmental processes. The main objective of this study was to assess the differences in forest fragmentation patterns and drivers between China and the conterminous United States (USA). Using the...
Geochemical constraints on the origin and volume of gas in the New Albany Shale (Devonian-Mississippian), eastern Illinois Basin
D. Strapoc, Maria Mastalerz, A. Schimmelmann, A. Drobniak, N.R. Hasenmueller
2010, American Association of Petroleum Geologists Bulletin (94) 1713-1740
This study involved analyses of kerogen petrography, gas desorption, geochemistry, microporosity, and mesoporosity of the New Albany Shale (Devonian-Mississippian) in the eastern part of the Illinois Basin. Specifically, detailed core analysis from two locations, one in Owen County, Indiana, and one in Pike County, Indiana, has been conducted. The gas...
Response to nestling throat ligatures by three songbirds
G.L. Robinson, C.J. Conway, C. Kirkpatrick, D.D. Laroche
2010, Wilson Journal of Ornithology (122) 806-809
We attempted to collect diet samples using throat ligatures from nestlings of three songbird species in a riparian woodland in southeastern Arizona from May to August 2009. We had success with Song Sparrows (Melospiza melodia), observed adult Yellow-breasted Chats (Icteria virens) reclaim food from nestlings, and discontinued the use of...
Preemption games: theory and experiment
Steven T. Anderson, Daniel Friedman, Ryan Oprea
2010, American Economic Review (100) 1778-1803
El Mutún, perhaps the world's largest remaining iron ore deposit, was opened to private investors in the 1980s but, due to the high cost of developing the remote Bolivian site, there were no takers for two decades. In late 2005, spurred by rising commodity prices, the Brazilian company EBX finally...
Uncovering a latent multinomial: Analysis of mark-recapture data with misidentification
W.A. Link, J. Yoshizaki, L.L. Bailey, K. H. Pollock
2010, Biometrics (66) 178-185
Natural tags based on DNA fingerprints or natural features of animals are now becoming very widely used in wildlife population biology. However, classic capture-recapture models do not allow for misidentification of animals which is a potentially very serious problem with natural tags. Statistical analysis of misidentification processes is extremely difficult...
Recruitment in a Colorado population of big brown bats: Breeding probabilities, litter size, and first-year survival
T. J. O'Shea, L.E. Ellison, D.J. Neubaum, M.A. Neubaum, C.A. Reynolds, R. A. Bowen
2010, Journal of Mammalogy (91) 418-428
We used markrecapture estimation techniques and radiography to test hypotheses about 3 important aspects of recruitment in big brown bats (Eptesicus fuscus) in Fort Collins, Colorado: adult breeding probabilities, litter size, and 1st-year survival of young. We marked 2,968 females with passive integrated transponder (PIT) tags at multiple sites during...
Life history and demographics of the endangered birdwing pearlymussel (Lemiox rimosus) (Bivalvia: Unionidae)
Jess W. Jones, Richard J. Neves, Steven A. Ahlstedt, Don Hubbs, Matthew Johnson, Hua Dan, Brett J.K. Ostby
2010, American Midland Naturalist (163) 335-350
The life history and population demography of the endangered birdwing pearlymussel (Lemiox rimosus) were studied in the Clinch and Duck rivers, Tennessee. Reproducing populations of L. rimosus now occur only in the Clinch, Duck and Powell rivers, as the species is considered extirpated from the remaining portions of its...
Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: STATSGO Soil Characteristics
Michael Wieczorek, Andrew E. LaMotte
2010, Data Series 491-26
This tabular data set represents estimated soil variables compiled for every MRB_E2RF1 catchment of selected Major River Basins (MRBs, Crawford and others, 2006). The variables included are cation exchange capacity, percent calcium carbonate, slope, water-table depth, soil thickness, hydrologic soil group, soil erodibility (k-factor), permeability, average water capacity, bulk density,...
Agriculture and food availability -- remote sensing of agriculture for food security monitoring in the developing world
Michael E. Budde, James Rowland, Christopher C. Funk
2010, Earthzine
For one-sixth of the world’s population - roughly 1 billion children, women and men - growing, buying or receiving adequate, affordable food to eat is a daily uncertainty. The World Monetary Fund reports that food prices worldwide increased 43 percent in 2007-2008, and unpredictable growing conditions make subsistence farming, on...
Migration of northern yellowstone elk: Implications of spatial structuring
P.J. White, K.M. Proffitt, L.D. Mech, S.B. Evans, J.A. Cunningham, K.L. Hamlin
2010, Journal of Mammalogy (91) 827-837
Migration can enhance survival and recruitment of mammals by increasing access to higher-quality forage or reducing predation risk, or both. We used telemetry locations collected from 140 adult female elk during 20002003 and 20072008 to identify factors influencing the migration of northern Yellowstone elk. Elk wintered in 2 semidistinct herd...
The role of soil drainage class in carbon dioxide exchange and decomposition in boreal black spruce (Picea mariana) forest stands
K.P. Wickland, J. C. Neff, J.W. Harden
2010, Canadian Journal of Forest Research (40) 2123-2134
Black spruce (Picea mariana (Mill.) B.S.P.) forest stands range from well drained to poorly drained, typically contain large amounts of soil organic carbon (SOC), and are often underlain by permafrost. To better understand the role of soil drainage class in carbon dioxide (CO2) exchange and decomposition, we measured soil respiration...
Laboratory chalcopyrite oxidation by Acidithiobacillus ferrooxidans: Oxygen and sulfur isotope fractionation
R.S. Thurston, K.W. Mandernack, Wayne C. Shanks III
2010, Chemical Geology (269) 252-261
Laboratory experiments were conducted to simulate chalcopyrite oxidation under anaerobic and aerobic conditions in the absence or presence of the bacterium Acidithiobacillus ferrooxidans. Experiments were carried out with 3 different oxygen isotope values of water (??18OH2O) so that approach to equilibrium or steady-state isotope fractionation for different starting conditions could...
Estimating length of avian incubation and nestling stages in afrotropical forest birds from interval-censored nest records
T.R. Stanley, W.D. Newmark
2010, The Auk (127) 79-85
In the East Usambara Mountains in northeast Tanzania, research on the effects of forest fragmentation and disturbance on nest survival in understory birds resulted in the accumulation of 1,002 nest records between 2003 and 2008 for 8 poorly studied species. Because information on the length of the incubation and nestling...