Impacts of agricultural land use on biological integrity: A causal analysis
C.M. Riseng, M.J. Wiley, Robert W. Black, M.D. Munn
2011, Ecological Applications (21) 3128-3146
Agricultural land use has often been linked to nutrient enrichment, habitat degradation, hydrologic alteration, and loss of biotic integrity in streams. The U.S. Geological Survey's National Water Quality Assessment Program sampled 226 stream sites located in eight agriculture‐dominated study units across the United States to investigate the geographic variability and...
Regional spectral analysis of three moderate earthquakes in Northeastern North America
John Boatwright, Linda C. Seekins
2011, Bulletin of the Seismological Society of America (101) 1769-1782
We analyze Fourier spectra obtained from the horizontal components of broadband and accelerogram data from the 1997 Cap-Rouge, the 2002 Ausable Forks, and the 2005 Rivière-du-Loup earthquakes, recorded by Canadian and American stations sited on rock at hypocentral distances from 23 to 602 km. We check the recorded spectra closely...
Evaluation of groundwater discharge into small lakes based on the temporal distribution of radon-222
N. T. Dimova, W. C. Burnett
2011, Limnology and Oceanography (56) 486-494
In order to evaluate groundwater discharge into small lakes we constructed a model that is based on the budget of 222Rn (radon, t1/2=3.8 d) as a tracer. The main assumptions in our model are that the lake's waters are well‐mixed horizontally and vertically; the only significant 222Rn source is via groundwater discharge;...
A puzzling migratory detour : Are fueling conditions in Alaska driving the movement of juvenile sharp -tailed sandpipers ?
A. Lindstrom, Robert E. Gill Jr., S.E. Jamieson, B. McCaffery, Liv Wennerberg, M. Wikelski, M. Klaassen
2011, Condor (113) 129-139
Making a detour can be advantageous to a migrating bird if fuel-deposition rates at stopover sites along the detour are considerably higher than at stopover sites along a more direct route. One example of an extensive migratory detour is that of the Sharp-tailed Sandpiper (Calidris acuminata), of which large numbers...
Monoclinic tridymite in clast-rich impact melt rock from the Chesapeake Bay impact structure
John C. Jackson, J. Wright Horton Jr., I-Ming Chou, Harvey E. Belkin
2011, American Mineralogist (96) 81-88
X-ray diffraction and Raman spectroscopy confirm a rare terrestrial occurrence of monoclinic tridymite in clast-rich impact melt rock from the Eyreville B drill core in the Chesapeake Bay impact structure. The monoclinic tridymite occurs with quartz paramorphs after tridymite and K-feldspar in a microcrystalline groundmass of devitrified glass and Fe-rich...
The effects of isolation on the demography and genetic diversity of long-lived species: Implications for conservation and management of the gopher tortoise (Gopherus polyphemus)
J.R. Ennen, R.D. Birkhead, B.R. Kreiser, D.L. Gaillard, C.P. Qualls, J.E. Lovich
2011, Herpetological Conservation and Biology (6) 202-214
In the southeastern United States, habitat loss has fragmented the landscape and isolated many populations of this region's flora and fauna, which has presumably resulted in smaller population sizes and reduced levels of genetic diversity. For example, forestry practices and anthropogenic disturbances are both cited as factors fragmenting the once...
Host and viral ecology determine bat rabies seasonality and maintenance
D.B. George, C.T. Webb, Matthew L. Farnsworth, T. J. O'Shea, R. A. Bowen, D.L. Smith, T.R. Stanley, L.E. Ellison, C. E. Rupprecht
2011, Proceedings of the National Academy of Sciences of the United States of America (108) 10208-10213
Rabies is an acute viral infection that is typically fatal. Most rabies modeling has focused on disease dynamics and control within terrestrial mammals (e.g., raccoons and foxes). As such, rabies in bats has been largely neglected until recently. Because bats have been implicated as natural reservoirs for several emerging zoonotic...
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...
Effect of cryopreservation and in vitro culture of bovine fibroblasts on histone acetylation levels and in vitro development of hand-made cloned embryos
L. Chacon, M.C. Gomez, J.A. Jenkins, S.P. Leibo, G. Wirtu, B.L. Dresser, C.E. Pope
2011, Zygote (19) 255-264
In this study, the relative acetylation levels of histone 3 in lysine 9 (H3K9ac) in cultured and cryopreserved bovine fibroblasts was measured and we determined the influence of the epigenetic status of three cultured (C1, C2 and C3) donor cell lines on the in vitro development of reconstructed bovine embryos. Results...
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,...
Widespread seismicity excitation throughout central Japan following the 2011 M=9.0 Tohoku earthquake and its interpretation by Coulomb stress transfer
S. Toda, R.S. Stein, J. Lin
2011, Geophysical Research Letters (38)
We report on a broad and unprecedented increase in seismicity rate following the M=9.0 Tohoku mainshock for M ≥ 2 earthquakes over inland Japan, parts of the Japan Sea and Izu islands, at distances of up to 425 km from the locus of high (≥15 m) seismic slip on the...
Derivation of S and Pb in phanerozoic intrusion-related metal deposits from neoproterozoic sedimentary pyrite, Great Basin, United States
Peter G. Vikre, S.R. Poulson, Alan E. Koenig
2011, Economic Geology (106) 883-912
The thick (≤8 km), regionally extensive section of Neoproterozoic siliciclastic strata (terrigenous detrital succession, TDS) in the central and eastern Great Basin contains sedimentary pyrite characterized by mostly high δ34S values (−11.6 to 40.8‰, >70% exceed 10‰; 51 analyses) derived from reduction of seawater sulfate, and by markedly radiogenic Pb isotopes...
An Analysis of the Published Mineral Resource Estimates of the Haji-Gak Iron Deposit, Afghanistan
David M. Sutphin, Karine Renaud, Lawrence J. Drew
2011, Natural Resources Research (20) 329-353
The Haji-Gak iron deposit of eastern Bamyan Province, eastern Afghanistan, was studied extensively and resource calculations were made in the 1960s by Afghan and Russian geologists. Recalculation of the resource estimates verifies the original estimates for categories A (in-place resources known in detail), B (in-place resources known in moderate detail),...
Nonlinear site response in medium magnitude earthquakes near Parkfield, California
Justin L. Rubinstein
2011, Bulletin of the Seismological Society of America (101) 275-286
Careful analysis of strong-motion recordings of 13 medium magnitude earthquakes (3.7 ≤ M ≤ 6.5) in the Parkfield, California, area shows that very modest levels of shaking (approximately 3.5% of the acceleration of gravity) can produce observable changes in site response. Specifically, I observe a drop and subsequent recovery of...
A hierarchical spatial framework and database for the national river fish habitat condition assessment
L. Wang, D. Infante, P. Esselman, A. Cooper, D. Wu, W. Taylor, D. Beard, G. Whelan, A. Ostroff
2011, Fisheries (36) 436-449
Fisheries management programs, such as the National Fish Habitat Action Plan (NFHAP), urgently need a nationwide spatial framework and database for health assessment and policy development to protect and improve riverine systems. To meet this need, we developed a spatial framework and database using National Hydrography Dataset Plus (I-.100,000-scale); http://www.horizon-systems.com/nhdplus)....
Evaluating the effects of future climate change and elevated CO2 on the water use efficiency in terrestrial ecosystems of China
Q. Zhu, H. Jiang, C. Peng, J. Liu, X. Wei, X. Fang, S. Liu, G. Zhou, S. Yu
2011, Ecological Modelling (222) 2414-2429
Water use efficiency (WUE) is an important variable used in climate change and hydrological studies in relation to how it links ecosystem carbon cycles and hydrological cycles together. However, obtaining reliable WUE results based on site-level flux data remains a great challenge when scaling up to larger regional zones. Biophysical,...
Are temperate mature forests buffered from invasive lianas?
Noel B. Pavlovic, Stacey A. Leicht-Young
2011, Journal of the Torrey Botanical Society (138) 85-92
Mature and old-growth forests are often thought to be buffered against invasive species due to low levels of light and infrequent disturbance. Lianas (woody vines) and other climbing plants are also known to exhibit lower densities in older forests. As part of a larger survey of the lianas of the...
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...
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...
Quantifying Uncertainty in Model Predictions for the Pliocene (Plio-QUMP): Initial results
J.O. Pope, M. Collins, A.M. Haywood, Harry J. Dowsett, S.J. Hunter, D.J. Lunt, S.J. Pickering, M.J. Pound
2011, Palaeogeography, Palaeoclimatology, Palaeoecology (309) 128-140
Examination of the mid-Pliocene Warm Period (mPWP; ~ 3.3 to 3.0 Ma BP) provides an excellent opportunity to test the ability of climate models to reproduce warm climate states, thereby assessing our confidence in model predictions. To do this it is necessary to relate the uncertainty in model simulations of mPWP...
An acarologic survey and Amblyomma americanum distribution map with implications for tularemia risk in Missouri
H.E. Brown, K.F. Yates, G. Dietrich, K. MacMillan, C.B. Graham, S.M. Reese, Wm. S. Helterbrand, W.L. Nicholson, K. Blount, P.S. Mead, S.L. Patrick, R.J. Eisen
2011, American Journal of Tropical Medicine and Hygiene (84) 411-419
In the United States, tickborne diseases occur focally. Missouri represents a major focus of several tickborne diseases that includes spotted fever rickettsiosis, tularemia, and ehrlichiosis. Our study sought to determine the potential risk of human exposure to human-biting vector ticks in this area. We collected ticks in 79 sites in...
Gently dipping normal faults identified with Space Shuttle radar topography data in central Sulawesi, Indonesia, and some implications for fault mechanics
J.E. Spencer
2011, Earth and Planetary Science Letters (308) 267-276
Space-shuttle radar topography data from central Sulawesi, Indonesia, reveal two corrugated, domal landforms, covering hundreds to thousands of square kilometers, that are bounded to the north by an abrupt transition to typical hilly to mountainous topography. These domal landforms are readily interpreted as metamorphic core complexes, an interpretation consistent with a...
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...
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...