Comparative phylogeography of a coevolved community: Concerted population expansions in Joshua trees and four Yucca moths
C.I. Smith, S. Tank, W. Godsoe, J. Levenick, Espen Strand, T. Esque, O. Pellmyr
2011, PLoS ONE (6)
Comparative phylogeographic studies have had mixed success in identifying common phylogeographic patterns among co-distributed organisms. Whereas some have found broadly similar patterns across a diverse array of taxa, others have found that the histories of different species are more idiosyncratic than congruent. The variation in the results of comparative phylogeographic...
Feasibility of waveform inversion of Rayleigh waves for shallow shear-wave velocity using a genetic algorithm
C. Zeng, J. Xia, R. D. Miller, G.P. Tsoflias
2011, Journal of Applied Geophysics (75) 648-655
Conventional surface wave inversion for shallow shear (S)-wave velocity relies on the generation of dispersion curves of Rayleigh waves. This constrains the method to only laterally homogeneous (or very smooth laterally heterogeneous) earth models. Waveform inversion directly fits waveforms on seismograms, hence, does not have such a limitation. Waveforms of...
Divergence in forest-type response to climate and weather: Evidence for regional links between forest-type evenness and net primary productivity
J.B. Bradford
2011, Ecosystems (14) 975-986
Climate change is altering long-term climatic conditions and increasing the magnitude of weather fluctuations. Assessing the consequences of these changes for terrestrial ecosystems requires understanding how different vegetation types respond to climate and weather. This study examined 20 years of regional-scale remotely sensed net primary productivity (NPP) in forests of the...
The efficacy of salvage logging in reducing subsequent fire severity in conifer-dominated forests of Minnesota, USA
S. Fraver, T. Jain, J.B. Bradford, A.W. D’Amato, D. Kastendick, B. Palik, D. Shinneman, J. Stanovick
2011, Ecological Applications (21) 1895-1901
Although primarily used to mitigate economic losses following disturbance, salvage logging has also been justified on the basis of reducing fire risk and fire severity; however, its ability to achieve these secondary objectives remains unclear. The patchiness resulting from a sequence of recent disturbances—blowdown, salvage logging, and wildfire—provided an excellent...
Breeding chorus indices are weakly related to estimated abundance of boreal chorus frogs
P.S. Corn, E. Muths, A.M. Kissel, R. D. Scherer
2011, Copeia (2011) 365-371
Call surveys used to monitor breeding choruses of anuran amphibians generate index values that are frequently used to represent the number of male frogs present, but few studies have quantified this relationship. We compared abundance of male Boreal Chorus Frogs (Pseudacris maculata), estimated using capture–recapture methods in two populations in...
Metallothionein-like multinuclear clusters of mercury(II) and sulfur in peat
K. L. Nagy, A. Manceau, J. D. Gasper, J. N. Ryan, G. R. Aiken
2011, Environmental Science & Technology (45) 7298-7306
Strong mercury(II)–sulfur (Hg-SR) bonds in natural organic matter, which influence mercury bioavailability, are difficult to characterize. We report evidence for two new Hg-SR structures using X-ray absorption spectroscopy in peats from the Florida Everglades with added Hg. The first, observed at...
Simultaneous speciation of arsenic, selenium, and chromium: Species stability, sample preservation, and analysis of ash and soil leachates
R.E. Wolf, S.A. Morman, P. L. Hageman, T.M. Hoefen, G.S. Plumlee
2011, Analytical and Bioanalytical Chemistry (401) 2733-2745
An analytical method using high-performance liquid chromatography separation with inductively coupled plasma mass spectrometry (ICP-MS) detection previously developed for the determination of Cr(III) and Cr(VI) has been adapted to allow the determination of As(III), As(V), Se(IV), Se(VI), Cr(III), and Cr(VI) under the same chromatographic conditions. Using this method, all six...
Marine and terrestrial factors affecting Adélie penguin Pygoscelis adeliae chick growth and recruitment off the western Antarctic Peninsula
Erik W. Chapman, Eileen E. Hofmann, Donna L. Patterson, Christine A. Ribic, William R. Fraser
2011, Marine Ecology Progress Series (436) 273-289
An individual-based bioenergetics model that simulates the growth of an Adélie penguin Pygoscelis adeliaechick from hatching to fledging was used to assess marine and terrestrial factors that affect chick growth and fledging mass off the western Antarctic Peninsula. Simulations considered the effects on Adélie penguin fledging mass of (1) modification of...
Review: Regional land subsidence accompanying groundwater extraction
Devin L. Galloway, Thomas J. Burbey
2011, Hydrogeology Journal (19) 1459-1486
The extraction of groundwater can generate land subsidence by causing the compaction of susceptible aquifer systems, typically unconsolidated alluvial or basin-fill aquifer systems comprising aquifers and aquitards. Various ground-based and remotely sensed methods are used to measure and map subsidence. Many areas of subsidence caused by groundwater pumping have been...
Fine-scale spatio-temporal variation in tiger Panthera tigris diet: Effect of study duration and extent on estimates of tiger diet in Chitwan National Park, Nepal
Paul M. Kapfer, Henry M. Streby, B. Gurung, A. Simcharoen, C.C. McDougal, J.L.D. Smith
2011, Wildlife Biology (17) 277-285
Attempts to conserve declining tiger Panthera tigris populations and distributions have experienced limited success. The poaching of tiger prey is a key threat to tiger persistence; a clear understanding of tiger diet is a prerequisite to conserve dwindling populations. We used unpublished data on tiger diet in combination with two previously...
Sources and Delivery of Nutrients to the Northwestern Gulf of Mexico from Streams in the South-Central United States
Richard A. Rebich, Natalie A. Houston, Scott V. Mize, Daniel Pearson, Patricia B. Ging, Hornig C. Evan
2011, Journal of the American Water Resources Association (47) 1061-1086
SPAtially Referenced Regressions On Watershed attributes (SPARROW) models were developed to estimate nutrient inputs [total nitrogen (TN) and total phosphorus (TP)] to the northwestern part of the Gulf of Mexico from streams in the South‐Central United States (U.S.). This area included drainages of the Lower Mississippi, Arkansas‐White‐Red, and Texas‐Gulf hydrologic...
A natural experiment on the condition-dependence of achromatic plumage reflectance in black-capped chickadees
L. D'Alba, Caroline R. Van Hemert, Colleen M. Handel, M.D. Shawkey
2011, PLoS ONE (6)
Honest advertisement models posit that only individuals in good health can produce and/or maintain ornamental traits. Even though disease has profound effects on condition, few studies have experimentally tested its effects on trait expression and even fewer have identified a mechanistic basis for these effects. Recent evidence suggests that black...
Sediment dynamics and the burial and exhumation of bedrock reefs along an emergent coastline as elucidated by repetitive sonar surveys: Northern Monterey Bay, CA
C. D. Storlazzi, T.A. Fregoso, N.E. Golden, D.P. Finlayson
2011, Marine Geology (289) 46-59
Two high-resolution bathymetric and acoustic backscatter sonar surveys were conducted along the energetic emergent inner shelf of northern Monterey Bay, CA, USA, in the fall of 2005 and the spring of 2006 to determine the impact of winter storm waves, beach erosion, and river floods on biologically-important siliclastic bedrock reef...
On the Hydrologic Adjustment of Climate-Model Projections: The Potential Pitfall of Potential Evapotranspiration
Paul C.D. Milly, Krista A. Dunne
2011, Earth Interactions (15) 1-14
Hydrologic models often are applied to adjust projections of hydroclimatic change that come from climate models. Such adjustment includes climate-bias correction, spatial refinement ("downscaling"), and consideration of the roles of hydrologic processes that were neglected in the climate model. Described herein is a quantitative analysis of the effects of hydrologic...
A probabilistic seismic risk assessment procedure for nuclear power plants: (I) Methodology
Y.-N. Huang, A.S. Whittaker, N. Luco
2011, Nuclear Engineering and Design (241) 3996-4003
A new procedure for probabilistic seismic risk assessment of nuclear power plants (NPPs) is proposed. This procedure modifies the current procedures using tools developed recently for performance-based earthquake engineering of buildings. The proposed procedure uses (a) response-based fragility curves to represent the capacity of structural and nonstructural components of NPPs,...
Habitat use and movement of the endangered Arroyo Toad (Anaxyrus californicus) in coastal southern California
M.J. Mitrovich, E.A. Gallegos, L.M. Lyren, R.E. Lovich, Robert N. Fisher
2011, Journal of Herpetology (45) 319-328
Information on the habitat use and movement patterns of Arroyo Toads (Anaxyrus californicus) is limited. The temporal and spatial characteristics of terrestrial habitat use, especially as it relates to upland use in coastal areas of the species' range, are poorly understood. We present analyses of radiotelemetry data from 40...
Late-Holocene climate evolution at the WAIS Divide site, West Antarctica: Bubble number-density estimates
John M. Fegyveresi, R. B. Alley, M. K. Spencer, J. J. Fitzpatrick, E.J. Steig, J.W.C. White, J.R. McConnell, K.C. Taylor
2011, Journal of Glaciology (57) 629-638
A surface cooling of ∼1.7°C occurred over the ∼two millennia prior to ∼1700 CE at the West Antarctic ice sheet (WAIS) Divide site, based on trends in observed bubble number-density of samples from the WDC06A ice core, and on an independently constructed accumulation-rate history using annual-layer dating corrected for density...
Temperature, hydric environment, and prior pathogen exposure alter the experimental severity of chytridiomycosis in boreal toads
Peter J. Murphy, Sophie St-Hilaire, Paul Stephen Corn
2011, Diseases of Aquatic Organisms (95) 31-42
Prevalence of the pathogen Batrachochytrium dendrobatidis (Bd), implicated in amphibian population declines worldwide, is associated with habitat moisture and temperature, but few studies have varied these factors and measured the response to infection in amphibian hosts. We evaluated how varying humidity, contact with water, and temperature affected the manifestation of...
The Regionalization of National-Scale SPARROW Models for Stream Nutrients
Gregory E. Schwarz, Richard B. Alexander, Richard A. Smith, Stephen D. Preston
2011, Journal of the American Water Resources Association (47) 1151-1172
This analysis modifies the parsimonious specification of recently published total nitrogen (TN) and total phosphorus (TP) national‐scale SPAtially Referenced Regressions On Watershed attributes models to allow each model coefficient to vary geographically among three major river basins of the conterminous United States. Regionalization of the national models reduces the standard...
Estimating water supply arsenic levels in the New England bladder cancer study
J.R. Nuckols, Freeman L.E. Beane, J.H. Lubin, M.S. Airola, D. Baris, J. D. Ayotte, A. Taylor, C. Paulu, M.R. Karagas, J. Colt, M.H. Ward, A.-T. Huang, W. Bress, S. Cherala, D.T. Silverman, K.P. Cantor
2011, Environmental Health Perspectives (119) 1279-1285
Background: Ingestion of inorganic arsenic in drinking water is recognized as a cause of bladder cancer when levels are relatively high (≥ 150 µg/L). The epidemiologic evidence is less clear at the low-to-moderate concentrations typically observed in the United States. Accurate retrospective exposure assessment over a long time period is...
A Miocene river in northern Arizona and its implications for the Colorado River and Grand Canyon
Ivo Lucchitta, Richard F. Holm, Baerbel K. Lucchitta
2011, GSA Today (21) 4-10
The southwesterly course of the pre–late Miocene Crooked Ridge River can be traced continuously for 48 km and discontinuously for 91 km in northern Arizona. It is visible today in inverted relief. Pebbles in the river gravel came from at least as far northeast as the San Juan Mountains. The...
East Antarctic rifting triggers uplift of the Gamburtsev Mountains
Fausto Ferraccioli, Carol A. Finn, Tom A. Jordan, Robin E. Bell, Lester M. Anderson, Detlef Damaske
2011, Nature (479) 388-392
The Gamburtsev Subglacial Mountains are the least understood tectonic feature on Earth, because they are completely hidden beneath the East Antarctic Ice Sheet. Their high elevation and youthful Alpine topography, combined with their location on the East Antarctic craton, creates a paradox that has puzzled researchers since the mountains were...
High-frequency Born synthetic seismograms based on coupled normal modes
F. Pollitz
2011, Geophysical Journal International (187) 1420-1442
High-frequency and full waveform synthetic seismograms on a 3-D laterally heterogeneous earth model are simulated using the theory of coupled normal modes. The set of coupled integral equations that describe the 3-D response are simplified into a set of uncoupled integral equations by using the Born approximation to calculate scattered...
Quantifying the hydrological responses to climate change in an intact forested small watershed in Southern China
G. Zhou, X. Wei, Y. Wu, Y. Huang, J. Yan, Dongxiao Zhang, Q. Zhang, J. Liu, Z. Meng, C. Wang, G. Chu, S. Liu, X. Tang, Xiuying Liu
2011, Global Change Biology (17) 3736-3746
Responses of hydrological processes to climate change are key components in the Intergovernmental Panel for Climate Change (IPCC) assessment. Understanding these responses is critical for developing appropriate mitigation and adaptation strategies for sustainable water resources management and protection of public safety. However, these responses are not well understood and little...
Integration of Palmer Drought Severity Index and remote sensing data to simulate wetland water surface from 1910 to 2009 in Cottonwood Lake area, North Dakota
Shengli Huang, Devendra Dahal, Claudia Young, Gyanesh Chander, Shuguang Liu
2011, Remote Sensing of Environment (115) 3377-3389
Spatiotemporal variations of wetland water in the Prairie Pothole Region are controlled by many factors; two of them are temperature and precipitation that form the basis of the Palmer Drought Severity Index (PDSI). Taking the 196 km2 Cottonwood Lake area in North Dakota as our pilot study site, we integrated PDSI, Landsat...
