Detecting aseismic strain transients from seismicity data
Andrea L. Llenos, Jeffrey J. McGuire
2011, Journal of Geophysical Research B: Solid Earth (116)
Aseismic deformation transients such as fluid flow, magma migration, and slow slip can trigger changes in seismicity rate. We present a method that can detect these seismicity rate variations and utilize these anomalies to constrain the underlying variations in stressing rate. Because ordinary aftershock sequences often obscure changes in the...
Evaluating the effect of predators on white-tailed deer: Movement and diet of coyotes
M.M. Turner, A.P. Rockhill, C.S. Deperno, J.A. Jenks, R. W. Klaver, A.R. Jarding, T.W. Grovenburg, K. H. Pollock
2011, Journal of Wildlife Management (75) 905-912
Coyotes (Canis latrans) may affect adult and neonate white-tailed deer (Odocoileus virginianus) survival and have been implicated as a contributor to the decline of deer populations. Additionally, coyote diet composition is influenced by prey availability, season, and region. Because coyote movement and diet vary by region, local data are important...
A perspective on nonstationarity and water management
R.M. Hirsch
2011, Journal of the American Water Resources Association (47) 436-446
This essay offers some perspectives on climate-related nonstationarity and water resources. Hydrologists must not lose sight of the many sources of nonstationarity, recognizing that many of them may be of much greater magnitude than those that may arise from climate change. It is paradoxical that statistical and deterministic approaches give...
Cougar survival and source-sink structure on Greater Yellowstone's Northern Range
T.K. Ruth, M.A. Haroldson, K.M. Murphy, P.C. Buotte, M.G. Hornocker, H.B. Quigley
2011, Journal of Wildlife Management (75) 1381-1398
We studied survival and causes of mortality of radiocollared cougars (Puma concolor) on the Greater Yellowstone Northern Range (GYNR) prior to (1987–1994) and after wolf (Canis lupus) reintroduction (1998–2005) and evaluated temporal, spatial, and environmental factors that explain variation in adult, subadult, and kitten survival. Using Program MARK and multimodel...
Potential effects of alpha-recoil on uranium-series dating of calcrete
L.A. Neymark
2011, Chemical Geology (282) 98-112
Evaluation of paleosol ages in the vicinity of Yucca Mountain, Nevada, at the time the site of a proposed high-level nuclear waste repository, is important for fault-displacement hazard assessment. Uranium-series isotope data were obtained for surface and subsurface calcrete samples from trenches and boreholes in Midway Valley, Nevada, adjacent to...
Are soils of Iowa USA currently a carbon sink or source? Simulated changes in SOC stock from 1972 to 2007
Shuguang Liu, Z. Tan, Z. Li, S. Zhao, W. Yuan
2011, Agriculture, Ecosystems and Environment (140) 106-112
Upscaling the spatial and temporal changes in carbon (C) stocks and fluxes from sites to regions is a critical and challenging step toward improving our understanding of the dynamics of C sources and sinks over large areas. This study simulated soil organic C (SOC) dynamics within 0–100 cm depth of soils...
2011 statistical abstract of the United States
Joseph M. Krisanda
2011, Report
<p>The <i>Statistical Abstract of the United States</i>, published since 1878, is the authoritative and comprehensive summary of statistics on the social, political, and economic organization of the United States.</p> <br/> <p>Use the Abstract as a convenient volume for statistical reference, and as a guide to sources of more information both...
Circum-Arctic mapping project: New magnetic and gravity anomaly maps of the Arctic
C. Gaina, S.C. Werner, R. Saltus, S. Maus, S. Aaro, D. Damaske, R. Forsberg, V. Glebovsky, Kevin K. Johnson, J. Jonberger, T. Koren, J. Korhonen, T. Litvinova, G. Oakey, O. Olesen, O. Petrov, M. Pilkington, T. Rasmussen, B. Schreckenberger, M. Smelror
2011, Geological Society Memoir 39-48
New Circum-Arctic maps of magnetic and gravity anomalies have been produced by merging regional gridded data. Satellite magnetic and gravity data were used for quality control of the long wavelengths of the new compilations. The new Circum-Arctic digital compilations of magnetic, gravity and some of their derivatives have been analyzed...
Predator-induced demographic shifts in coral reef fish assemblages
B.I. Ruttenberg, S.L. Hamilton, S.M. Walsh, Mary Donovan, Alan M. Friedlander, E. DeMartini, E. Sala, S.A. Sandin
2011, PLoS ONE (6)
In recent years, it has become apparent that human impacts have altered community structure in coastal and marine ecosystems worldwide. Of these, fishing is one of the most pervasive, and a growing body of work suggests that fishing can have strong effects on the ecology of target species, especially top...
Evidence of two genetic clusters of manatees with low genetic diversity in Mexico and implications for their conservation
C. Nourisson, B. Morales-Vela, J. Padilla-Saldivar, K.P. Tucker, A. Clark, L. D. Olivera-Gomez, Robert K. Bonde, P. McGuire
2011, Genetica (139) 833-842
The Antillean manatee (Trichechus manatus manatus) occupies the tropical coastal waters of the Greater Antilles and Caribbean, extending from Mexico along Central and South America to Brazil. Historically, manatees were abundant in Mexico, but hunting during the pre-Columbian period, the Spanish colonization and throughout the history of Mexico, has resulted...
Cooling rates and the depth of detachment faulting at oceanic core complexes: Evidence from zircon Pb/U and (U-Th)/He ages
Craig B. Grimes, Michael J. Cheadle, Barbara E. John, P.W. Reiners, J. L. Wooden
2011, Geochemistry, Geophysics, Geosystems (12)
Oceanic detachment faulting represents a distinct mode of seafloor spreading at slow spreading mid‐ocean ridges, but many questions persist about the thermal evolution and depth of faulting. We present new Pb/U and (U‐Th)/He zircon ages and combine them with magnetic anomaly ages to define the cooling histories of gabbroic crust...
A lognormal distribution of metal resources
Donald A. Singer
2011, Diqiu Kexue - Zhongguo Dizhi Daxue Xuebao/Earth Science - Journal of China University of Geosciences (36) 201-208
For national or global resource estimation of frequencies of metals, a lognormal distribution has commonly been recommended but not adequately tested. Tests of frequencies of Cu, Zn, Pb, Ag, and Au contents of 1 984 well-explored mineral deposits display a poor fit to the lognormal distribution. When the same metals...
Adaptive management of natural resources-framework and issues
Byron K. Williams
2011, Journal of Environmental Management (92) 1346-1353
Adaptive management, an approach for simultaneously managing and learning about natural resources, has been around for several decades. Interest in adaptive decision making has grown steadily over that time, and by now many in natural resources conservation claim that...
Ground-Motion Prediction Equations (GMPEs) from a global dataset: The PEER NGA equations
David M. Boore
Sinan Akkar, Polat Gulkan, Torild van Eck, editor(s)
2011, Book chapter, Earthquake Data in Engineering Seismology: Predictive Models, Data Management, and Networks
The PEER NGA ground-motion prediction equations (GMPEs) were derived by five developer teams over several years, resulting in five sets of GMPEs. The teams used various subsets of a global database of ground motions and metadata from shallow earthquakes in tectonically active regions in the development of the equations. Since...
Scaling earthquake ground motions for performance-based assessment of buildings
Y.-N. Huang, A.S. Whittaker, N. Luco, R.O. Hamburger
2011, Journal of Structural Engineering (137) 311-321
The impact of alternate ground-motion scaling procedures on the distribution of displacement responses in simplified structural systems is investigated. Recommendations are provided for selecting and scaling ground motions for performance-based assessment of buildings. Four scaling methods are studied, namely, (1) geometric-mean scaling of pairs of ground motions, (2) spectrum...
Reduction of garbage in the diet of nonbreeding glaucous gulls corresponding to a change in waste management
Emily L. Weiser, Abby N. Powell
2011, Arctic (64) 220-226
Glaucous gulls (Larus hyperboreus) are major predators in the Arctic and may benefit from human development. We studied use of garbage by glaucous gulls in Barrow, Alaska, in 2007, when municipal waste was disposed of in a landfill, and in 2008, when it was incinerated. In both years, diet samples...
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...
ASTER spectral analysis and lithologic mapping of the Khanneshin carbonatite volcano, Afghanistan
John C. Mars, Lawrence C. Rowan
2011, Geosphere (7) 276-289
Advanced Spaceborne Thermal and Reflection Radiometer (ASTER) data of the early Quaternary Khanneshin carbonatite volcano located in southern Afghanistan were used to identify carbonate rocks within the volcano and to distinguish them from Neogene ferruginous polymict sandstone and argillite. The carbonatitic rocks are characterized by diagnostic CO3 absorption near 11.2...
Comparison of Bayesian clustering and edge detection methods for inferring boundaries in landscape genetics
T. Safner, Mark P. Miller, B.H. McRae, M.-J. Fortin, S. Manel
2011, International Journal of Molecular Sciences (12) 865-889
Recently, techniques available for identifying clusters of individuals or boundaries between clusters using genetic data from natural populations have expanded rapidly. Consequently, there is a need to evaluate these different techniques. We used spatially-explicit simulation models to compare three spatial Bayesian clustering programs and two edge detection methods. Spatially-structured populations...
Chemically mediated interactions between macroalgae Dictyota spp. and multiple life-history stages of the coral Porites astreoides
V.J. Paul, Ilsa B. Kuffner, L.J. Walters, R. Ritson-Williams, K.S. Beach, M.A. Becerro
2011, Marine Ecology Progress Series (426) 161-170
Competition between corals and macroalgae is often assumed to occur on reefs, especially those that have undergone shifts from coral to algal dominance; however, data examining these competitive interactions, especially during the early life-history stages of corals, are scarce. We conducted a series of field and outdoor seawater-table experiments to...
Process-based modeling of tsunami inundation and sediment transport
A. Apotsos, G. Gelfenbaum, B. Jaffe
2011, Journal of Geophysical Research F: Earth Surface (116)
The infrequent and unpredictable nature of tsunamis precludes the use of field experiments to measure the hydrodynamic and sediment transport processes that occur. Instead, these processes are often approximated from laboratory, numerical, and theoretical studies or inferred from observations of the resultant sediment deposits. Here Delft3D, a three-dimensional numerical model,...
Enhanced transpiration by riparian buffer trees in response to advection in a humid temperate agricultural landscape
V. Hernandez-Santana, H. Asbjornsen, T. Sauer, T. Isenhart, K. Schilling, Ronald Schultz
2011, Forest Ecology and Management (261) 1415-1427
Riparian buffers are designed as management practices to increase infiltration and reduce surface runoff and transport of sediment and nonpoint source pollutants from crop fields to adjacent streams. Achieving these ecosystem service goals depends, in part, on their ability to remove water from the soil via transpiration. In these systems,...
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...
Western Arctic Ocean temperature variability during the last 8000 years
Jesse R. Farmer, Thomas M. Cronin, Anne De Vernal, Gary S. Dwyer, Loyd D. Keigwin, Robert C. Thunell
2011, Geophysical Research Letters (38)
We reconstructed subsurface (∼200–400 m) ocean temperature and sea-ice cover in the Canada Basin, western Arctic Ocean from foraminiferal δ18O, ostracode Mg/Ca ratios, and dinocyst assemblages from two sediment core records covering the last 8000 years. Results show mean temperature varied from −1 to 0.5°C and −0.5 to 1.5°C at...
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...
