Synthesis of isotopically modified ZnO nanoparticles and their potential as nanotoxicity tracers
A.D. Dybowska, Marie Noele Croteau, S.K. Misra, D. Berhanu, Samuel N. Luoma, P. Christian, P. O'Brien, E. Valsami-Jones
2011, Environmental Pollution (159) 266-273
Understanding the behavior of engineered nanoparticles in the environment and within organisms is perhaps the biggest obstacle to the safe development of nanotechnologies. Reliable tracing is a particular issue for nanoparticles such as ZnO, because Zn is an essential element and a common pollutant thus present at elevated background concentrations. We synthesized isotopically...
Understanding the role of fog in forest hydrology: Stable isotopes as tools for determining input and partitioning of cloud water in montane forests
Martha A. Scholl, W. Eugster, R. Burkard
2011, Hydrological Processes (25) 353-366
Understanding the hydrology of tropical montane cloud forests (TMCF) has become essential as deforestation of mountain areas proceeds at an increased rate worldwide. Passive and active cloud‐water collectors, throughfall and stemflow collectors, visibility or droplet size measurements, and micrometeorological sensors are typically used to measure the fog water inputs to...
Melt fracturing and healing: A mechanism for degassing and origin of silicic obsidian
A. Cabrera, R.F. Weinberg, Heather M. Wright, S. Zlotnik, Ray A.F. Cas
2011, Geology (39) 67-70
We present water content transects across a healed fault in pyroclastic obsidian from Lami pumice cone, Lipari, Italy, using synchrotron Fourier transform infrared spectroscopy. Results indicate that rhyolite melt degassed through the fault surface. Transects define a trough of low water content coincident with the fault trace, surrounded on either...
Critical nitrogen deposition loads in high-elevation lakes of the western US inferred from paleolimnological records
J.E. Saros, David W. Clow, T. Blett, A.P. Wolfe
2011, Water, Air, & Soil Pollution (216) 193-202
Critical loads of nitrogen (N) from atmospheric deposition were determined for alpine lake ecosystems in the western US using fossil diatom assemblages in lake sediment cores. Changes in diatom species over the last century were indicative of N enrichment in two areas, the eastern Sierra Nevada, starting between 1960 and...
The Augustine magmatic system as revealed by seismic tomography and relocated earthquake hypocenters from 1994 through 2009
E.M. Syracuse, C.H. Thurber, John A. Power
2011, Journal of Geophysical Research B: Solid Earth (116)
We incorporate 14 years of earthquake data from the Alaska Volcano Observatory with data from a 1975 controlled‐source seismic experiment to obtain the three‐dimensional P and S wave velocity structure and the first high‐precision earthquake locations at Augustine Volcano to be calculated in a fully three‐dimensional velocity model. Velocity tomography...
Fish entrainment rates through towboat propellers in the Upper Mississippi and Illinois rivers
Killgore K. Jack, Leandro E. Miranda, C.E. Murphy, D.M. Wolff, J.J. Hoover, T.M. Keevin, S.T. Maynord, M.A. Cornish
2011, Transactions of the American Fisheries Society (140) 570-581
A specially designed net was used to study fish entrainment and injury through towboat propellers in 13 pools of the Upper Mississippi and Illinois rivers. The net was attached to the stern of a 48.8‐m‐long towboat with twin propellers (in Kort propulsion nozzles), and sampling typically took place while the...
Simulating adsorption of U(VI) under transient groundwater flow and hydrochemistry: Physical versus chemical nonequilibrium model
J. Greskowiak, M.B. Hay, H. Prommer, C. Liu, V.E.A. Post, R. Ma, J.A. Davis, C. Zheng, J.M. Zachara
2011, Water Resources Research (47)
Coupled intragrain diffusional mass transfer and nonlinear surface complexation processes play an important role in the transport behavior of U(VI) in contaminated aquifers. Two alternative model approaches for simulating these coupled processes were analyzed and compared: (1) the physical nonequilibrium approach that explicitly accounts for aqueous speciation and instantaneous surface...
Developing empirical collapse fragility functions for global building types
K. Jaiswal, D. Wald, D. D’Ayala
2011, Earthquake Spectra (27) 775-795
Building collapse is the dominant cause of casualties during earthquakes. In order to better predict human fatalities, the U.S. Geological Survey’s Prompt Assessment of Global Earthquakes for Response (PAGER) program requires collapse fragility functions for global building types. The collapse fragility is expressed as the probability of collapse at discrete...
When a habitat freezes solid: Microorganisms over-winter within the ice column of a coastal Antarctic lake
C.M. Foreman, M. Dieser, M. Greenwood, R.M. Cory, J. Laybourn-Parry, John T. Lisle, C. Jaros, P.L. Miller, Y.-P. Chin, Diane M. McKnight
2011, FEMS Microbiology Ecology (76) 401-412
A major impediment to understanding the biology of microorganisms inhabiting Antarctic environments is the logistical constraint of conducting field work primarily during the summer season. However, organisms that persist throughout the year encounter severe environmental changes between seasons. In an attempt to bridge this gap, we collected ice core samples...
A first look at the petroleum geology of the Lomonosov Ridge microcontinent, Arctic Ocean
Thomas E. Moore, Arthur Grantz, Janet K. Pitman, Philip J. Brown
2011, Geological Society Memoir (35) 751-769
The Lomonosov microcontinent is an elongated continental fragment that transects the Arctic Ocean between North America and Siberia via the North Pole. Although it lies beneath polar pack ice, the geological framework of the microcontinent is inferred from sparse seismic reflection data, a few cores, potential field data and the...
Gas geochemistry of the Mount Elbert Gas Hydrate Stratigraphic Test Well, Alaska North Slope: implications for gas hydrate exploration in the Arctic
T.D. Lorenson, T. S. Collett, R.B. Hunter
2011, Marine and Petroleum Geology (28) 343-360
Gases were analyzed from well cuttings, core, gas hydrate, and formation tests at the BPXA-DOE-USGS Mount Elbert Gas Hydrate Stratigraphic Test Well, drilled within the Milne Point Unit, Alaska North Slope. The well penetrated a portion of the Eileen gas hydrate deposit, which overlies the more deeply buried Prudhoe Bay,...
Regional magnetic domains of the Circum-Arctic: A framework for geodynamic interpretation
R. W. Saltus, E. L. Miller, C. Gaina, P. J. Brown
2011, Geological Society Memoir (35) 49-60
We identify and discuss 57 magnetic anomaly pattern domains spanning the Circum-Arctic. The domains are based on analysis of a new Circum-Arctic data compilation. The magnetic anomaly patterns can be broadly related to general geodynamic classification of the crust into stable, deformed (magnetic and nonmagnetic), deep magnetic high, oceanic and...
Stochastic population dynamics in populations of western terrestrial garter snakes with divergent life histories
David A. Miller, W.R. Clark, S.J. Arnold, A.M. Bronikowski
2011, Ecology (92) 1658-1671
Comparative evaluations of population dynamics in species with temporal and spatial variation in life‐history traits are rare because they require long‐term demographic time series from multiple populations. We present such an analysis using demographic data collected during the interval 1978–1996 for six populations of western terrestrial garter snakes (Thamnophis elegans)...
Coexistence in streams: Do source-sink dynamics allow salamanders to persist with fish predators?
Adam J. Sepulveda, W.H. Lowe
2011, Oecologia (166) 1043-1054
Theory suggests that source–sink dynamics can allow coexistence of intraguild predators and prey, but empirical evidence for this coexistence mechanism is limited. We used capture–mark–recapture, genetic methods, and stable isotopes to test whether source–sink dynamics promote coexistence between stream fishes, the intraguild predator, and stream salamanders (Dicamptodon aterrimus), the intraguild...
Are patterns in nutrient limitation belowground consistent with those aboveground: Results from a 4 million year chronosequence
Sasha C. Reed, P.M. Vitousek, C.C. Cleveland
2011, Biogeochemistry (106) 323-336
Accurately predicting the effects of global change on net carbon (C) exchange between terrestrial ecosystems and the atmosphere requires a more complete understanding of how nutrient availability regulates both plant growth and heterotrophic soil respiration. Models of soil development suggest that the nature of nutrient limitation changes over the course...
Estimating phosphorus availability for microbial growth in an emerging landscape
S.K. Schmidt, C.C. Cleveland, D.R. Nemergut, S.C. Reed, A.J. King, P. Sowell
2011, Geoderma (163) 135-140
Estimating phosphorus (P) availability is difficult—particularly in infertile soils such as those exposed after glacial recession—because standard P extraction methods may not mimic biological acquisition pathways. We developed an approach, based on microbial CO2 production kinetics and conserved carbon:phosphorus (C:P) ratios, to estimate the amount of P available for microbial...
Use of waveform lidar and hyperspectral sensors to assess selected spatial and structural patterns associated with recent and repeat disturbance and the abundance of sugar maple (Acer saccharum Marsh.) in a temperate mixed hardwood and conifer forest
J.E. Anderson, Mark J. Ducey, A. Fast, M.E. Martin, L. Lepine, M.-L. Smith, T.D. Lee, R.O. Dubayah, M.A. Hofton, P. Hyde, Birgit Peterson, J.B. Blair
2011, Journal of Applied Remote Sensing (5)
Waveform lidar imagery was acquired on September 26, 1999 over the Bartlett Experimental Forest (BEF) in New Hampshire (USA) using NASA's Laser Vegetation Imaging Sensor (LVIS). This flight occurred 20 months after an ice storm damaged millions of hectares of forestland in northeastern North America. Lidar measurements of the amplitude...
Does the "kamaroma"-plastron pattern morph occur in both Philippine subspecies of the turtle Cuora amboinensis?
C.H. Ernst, A.F. Laemmerzahl, Jeffrey E. Lovich
2011, Proceedings of the Biological Society of Washington (124) 259-269
Two subspecies of the turtle Cuora amboinensis have been reported from the Philippine Islands, C. a. amboinensis and C. a. kamaroma, distinguished primarily by their carapace morphology, and secondarily by their plastron patterns. We assessed the utility of using shell and postorbital-stripe morphology instead of plastron patterns to distinguish these putative taxa. Adult <span...
Thermal structure and dynamics of Saturn's northern springtime disturbance
L.N. Fletcher, B.E. Hesman, P.G.J. Irwin, K. H. Baines, T.W. Momary, A. Sanchez-Lavega, F.M. Flasar, P.L. Read, G.S. Orton, A. Simon-Miller, R. Hueso, G.L. Bjoraker, A. Mamoutkine, Rio-Gaztelurrutia Del, J.M. Gomez, B. Buratti, R. N. Clark, P. D. Nicholson, Christophe Sotin
2011, Science (332) 1413-1417
Saturn’s slow seasonal evolution was disrupted in 2010–2011 by the eruption of a bright storm in its northern spring hemisphere. Thermal infrared spectroscopy showed that within a month, the resulting planetary-scale disturbance had generated intense perturbations of atmospheric temperatures, winds, and composition between 20° and 50°N over an entire hemisphere...
Benthic macroinvertebrate and fish communities in Lake Huron are linked to submerged groundwater vents
Sanders T. Garrison, B.A. Biddanda, Craig A. Stricker, S.C. Nold
2011, Aquatic Biology (12) 1-12
Groundwater can be an important source of nutrients and energy to aquatic ecosystems, but quantifying the inputs and biogeochemical importance remains challenging. A series of submerged groundwater vents in northern Lake Huron were examined to determine the linkage between groundwater nutrients and aquatic food webs. We collected samples of key...
Estimation of land surface evapotranspiration with A satellite remote sensing procedure
A. Irmak, I. Ratcliffe, P. Ranade, K.G. Hubbard, Ramesh K. Singh, B. Kamble, J. Kjaersgaard
2011, Great Plains Research (21) 73-88
There are various methods available for estimating magnitude and trends of evapotranspiration. Bowen ratio energy balance system and eddy correlation techniques offer powerful alternatives for measuring land surface evapotranspiration. In spite of the elegance, high accuracy, and theoretical attractions of these techniques for measuring evapotranspiration, their practical use over large...
O2 reduction and denitrification rates in shallow aquifers
Anthony J. Tesoriero, Larry J. Puckett
2011, Water Resources Research (47)
O2 reduction and denitrification rates were determined in shallow aquifers of 12 study areas representing a wide range in sedimentary environments and climatic conditions. Zero‐ and first‐order rates were determined by relating reactant or product concentrations to apparent groundwater age. O2 reduction rates varied widely within and between sites, with zero‐order rates...
Perceptions of strengths and deficiencies: Disconnects between graduate students and prospective employers
M.D. Sundberg, P. Deangelis, K. Havens, K. Holsinger, K. Kennedy, A.T. Kramer, R. Muir, Peggy Olwell, K. Schierenbeck, L. Stritch, B. Zorn-Arnold
2011, BioScience (61) 133-138
The US Botanical Capacity Assessment Project (BCAP) was initiated as a first step to gauge the nation's collective ability to meet the environmental challenges of the 21st century. The project, in which the authors of this article are involved, specifically aimed to identify multisector contributions to and gaps in botanical...
Method for detecting moment connection fracture using high-frequency transients in recorded accelerations
J.E. Rodgers, Mehmet Celebi
2011, Journal of Constructional Steel Research (67) 293-307
The 1994 Northridge earthquake caused brittle fractures in steel moment frame building connections, despite causing little visible building damage in most cases. Future strong earthquakes are likely to cause similar damage to the many un-retrofitted pre-Northridge buildings in the western US and elsewhere. Without obvious permanent building deformation, costly intrusive...
Study relationship between inorganic and organic coal analysis with gross calorific value by multiple regression and ANFIS
S.C. Chelgani, B. Hart, W.C. Grady, J.C. Hower
2011, International Journal of Coal Preparation and Utilization (31) 9-19
The relationship between maceral content plus mineral matter and gross calorific value (GCV) for a wide range of West Virginia coal samples (from 6518 to 15330 BTU/lb; 15.16 to 35.66 MJ/kg) has been investigated by multivariable regression and adaptive neuro-fuzzy inference system (ANFIS). The stepwise least square mathematical method comparison between...
