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Page 1874, results 46826 - 46850

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Ecological hierarchies and self-organisation - Pattern analysis, modelling and process integration across scales
H. Reuter, F. Jopp, J. M. Blanco-Moreno, C. Damgaard, Y. Matsinos, D.L. DeAngelis
2010, Basic and Applied Ecology (11) 572-581
A continuing discussion in applied and theoretical ecology focuses on the relationship of different organisational levels and on how ecological systems interact across scales. We address principal approaches to cope with complex across-level issues in ecology by applying elements of hierarchy theory and the theory of complex adaptive systems. A...
Radiocarbon dating of small terrestrial gastropod shells in North America
J.S. Pigati, J.A. Rech, J.C. Nekola
2010, Quaternary Geochronology (5) 519-532
Fossil shells of small terrestrial gastropods are commonly preserved in wetland, alluvial, loess, and glacial deposits, as well as in sediments at many archeological sites. These shells are composed largely of aragonite (CaCO3) and potentially could be used for radiocarbon dating, but they must meet two criteria before their 14C...
Environmental drivers of fish functional diversity and composition in the Lower Colorado River Basin
T.K. Pool, J. D. Olden, Joanna B. Whittier, C.P. Paukert
2010, Canadian Journal of Fisheries and Aquatic Sciences (67) 1791-1807
Freshwater conservation efforts require an understanding of how natural and anthropogenic factors shape the present-day biogeography of native and non-native species. This knowledge need is especially acute for imperiled native fishes in the highly modified Lower Colorado River Basin (LCRB), USA. In the present study we employed both a taxonomic...
Effects of landscape features on waterbird use of rice fields
S. King, C.S. Elphick, D. Guadagnin, O. Taft, T. Amano
2010, Waterbirds (33) 151-159
Literature is reviewed to determine the effects of landscape features on waterbird use of fields in regions where rice (Oryza sativa) is grown. Rice-growing landscapes often consist of diverse land uses and land cover, including rice fields, irrigation ditches, other agricultural fields, grasslands, forests and natural wetlands. Numerous studies indicate...
Radiative forcing over the conterminous United States due to contemporary land cover land use change and sensitivity to snow and interannual albedo variability
Christopher A. Barnes, David P. Roy
2010, Journal of Geophysical Research: Biogeosciences (115) 1-14
Satellite-derived land cover land use (LCLU), snow and albedo data, and incoming surface solar radiation reanalysis data were used to study the impact of LCLU change from 1973 to 2000 on surface albedo and radiative forcing for 58 ecoregions covering 69% of the conterminous United States. A net positive surface...
It's not just about climate change - What about soils?
Martin B. Goldhaber
2010, Elements (6) 359-359
Vladimir Vernadsky was one of the giants of geochemistry. Considered the founder of the fi eld of biogeochemistry and a true pioneer in “whole Earth” studies, he realized by 1945 that “Man under our very eyes is becoming a mighty and ever-growing geological force.” In the intervening 65 years, his...
A review of silver-rich mineral deposits and their metallogeny
Frederick Graybeal, Peter G. Vikre
2010, Book chapter, The challenge of finding new mineral resources: Global metallogeny, innovative exploration, and new discoveries; SEG Special Publication 15 Vol. 1
Mineral deposits with large inventories or high grades of silver are found in four genetic groups: (1) volcanogenic massive sulfide (VMS), (2) sedimentary exhalative (SEDEX), (3) lithogene, and, (4) magmatichydrothermal. Principal differences between the four groups relate to source rocks and regions, metal associations, process and timing of mineralization, and...
Heat tracer methods
Richard W. Healy
2010, Book chapter, Estimating groundwater recharge
The flow of heat in the subsurface is closely linked to the movement of water (Ingebritsen et al., 2006). As such, heat has been used as a tracer in groundwater studies for more than 100 years (Anderson, 2005). As with chemical and isotopic tracers (Chapter 7), spatial or temporal...
Characterizing wet slab and glide slab avalanche occurrence along the Going-to-the-Sun Road, Glacier National Park, Montana, USA
Erich H. Peitzsch, Jordy Hendrikx, Daniel B. Fagre, Blase Reardon
2010, Conference Paper, Proceedings: 2010 international snow science workshop
Wet slab and glide slab snow avalanches are dangerous and yet can be particularly difficult to predict. Both wet slab and glide slab avalanches are thought to depend upon free water moving through the snowpack but are driven by different processes. In Glacier National Park, Montana, both types of avalanches...
Intensity, magnitude, location and attenuation in India for felt earthquakes since 1762
Walter Szeliga, Susan Hough, Stacey Martin, Roger G. Bilham
2010, Bulletin of the Seismological Society of America (100) 570-584
A comprehensive, consistently interpreted new catalog of felt intensities for India (Martin and Szeliga, 2010, this issue) includes intensities for 570 earthquakes; instrumental magnitudes and locations are available for 100 of these events. We use the intensity values for 29 of the instrumentally recorded events to develop new intensity versus...
Linking process to pattern: estimating spatiotemporal dynamics of a wildlife epidemic from cross‐sectional data
Dennis M. Heisey, Erik E. Osnas, Paul C. Cross, Damien O. Joly, Julia A. Langenberg, Michael W. Miller
2010, Ecological Monographs (80) 221-240
Underlying dynamic event processes unfolding in continuous time give rise to spatiotemporal patterns that are sometimes observable at only a few discrete times. Such event processes may be modulated simultaneously over several spatial (e.g., latitude and longitude) and temporal (e.g., age, calendar time, and cohort) dimensions. The ecological challenge is...
Modeling methods
Richard W. Healy
2010, Book chapter, Estimating groundwater recharge
Simulation models are widely used in all types of hydrologic studies, and many of these models can be used to estimate recharge. Models can provide important insight into the functioning of hydrologic systems by identifying factors that influence recharge. The predictive capability of models can be used to evaluate how...
A practitioner's tool for assessing glide crack activity
Jordy Hendrikx, Erich H. Peitzsch, Daniel B. Fagre
2010, Conference Paper, Proceedings, 2010 International Snow Science Workshop
Glide cracks can result in full-depth glide avalanche release. Avalanches from glide cracks are notoriously difficult to forecast, but are a reoccurring problem in a number of different avalanche forecasting programs across a range of snow climates. Despite this, there is no consensus for how to best manage, mitigate, or...
Controls on rind thickness on basaltic andesite clasts weathering in Guadeloupe
P.B. Sak, A. K. Navarre-Sitchler, C.E. Miller, C.C. Daniel, J. Gaillardet, H.L. Buss, M.I. Lebedeva, S.L. Brantley
2010, Chemical Geology (276) 129-143
A clast of low porosity basaltic andesite collected from the B horizon of a soil developed on a late Quaternary volcaniclastic debris flow in the Bras David watershed on Basse-Terre Island, Guadeloupe, exhibits weathering like that observed in many weathered clasts of similar composition in other tropical locations. Specifically, elemental...
Thematic accuracy of the NLCD 2001 land cover for the conterminous United States
J.D. Wickham, S.V. Stehman, J.A. Fry, J.H. Smith, Collin G. Homer
2010, Remote Sensing of Environment (114) 1286-1296
The land-cover thematic accuracy of NLCD 2001 was assessed from a probability-sample of 15,000 pixels. Nationwide, NLCD 2001 overall Anderson Level II and Level I accuracies were 78.7% and 85.3%, respectively. By comparison, overall accuracies at Level II and Level I for the NLCD 1992 were 58% and 80%. Forest and...
Inter-comparison of hydro-climatic regimes across northern catchments: Synchronicity, resistance and resilience
S.K. Carey, D. Tetzlaff, J. Seibert, C. Soulsby, J. Buttle, H. Laudon, J. McDonnell, K. McGuire, D. Caissie, J. Shanley, M. Kennedy, K. Devito, J.W. Pomeroy
2010, Hydrological Processes (24) 3591-3602
The higher mid-latitudes of the Northern Hemisphere are particularly sensitive to climate change as small differences in temperature determine frozen ground status, precipitation phase, and the magnitude and timing of snow accumulation and melt. An international inter-catchment comparison program, North-Watch, seeks to improve our understanding of the sensitivity of northern...
Effects of 3D random correlated velocity perturbations on predicted ground motions
S. Hartzell, S. Harmsen, A. Frankel
2010, Bulletin of the Seismological Society of America (100) 1415-1426
Three-dimensional, finite-difference simulations of a realistic finite-fault rupture on the southern Hayward fault are used to evaluate the effects of random, correlated velocity perturbations on predicted ground motions. Velocity perturbations are added to a three-dimensional (3D) regional seismic velocity model of the San Francisco Bay Area using a 3D von...
Evaluating propagation method performance over time with Bayesian updating: An application to incubator testing
Sarah J. Converse, J. N. Chandler, Glenn H. Olsen, C. C. Shafer
Barry K. Hartup, Richard P. Urbanek, editor(s)
2010, Book chapter, Proceedings of the Eleventh North American Crane Workshop
In captive-rearing programs, small sample sizes can limit the quality of information on performance of propagation methods. Bayesian updating can be used to increase information on method performance over time. We demonstrate an application to incubator testing at USGS Patuxent Wildlife Research Center. A new type of incubator was purchased...
Avian foods, foraging and habitat conservation in world rice fields
J.D. Stafford, R.M. Kaminski, K. J. Reinecke
2010, Waterbirds (33) 133-150
Worldwide, rice (Oryza sativa) agriculture typically involves seasonal flooding and soil tillage, which provides a variety of microhabitats and potential food for birds. Water management in rice fields creates conditions ranging from saturated mud flats to shallow (<30 cm) water, thereby attracting different guilds of birds. Grain not collected during...
Pollutant fate and spatio-temporal variability in the choptank river estuary: Factors influencing water quality
D. Whitall, W.D. Hively, A.K. Leight, C.J. Hapeman, L.L. McConnell, T. Fisher, C.P. Rice, E. Codling, G.W. McCarty, A.M. Sadeghi, A. Gustafson, K. Bialek
2010, Science of the Total Environment (408) 2096-2108
Restoration of the Chesapeake Bay, the largest estuary in the United States, is a national priority. Documentation of progress of this restoration effort is needed. A study was conducted to examine water quality in the Choptank River estuary, a tributary of the Chesapeake Bay that since 1998 has been classified...
Waterfowl ecology and avian influenza in california: Do host traits inform us about viral occurrence?
N.J. Hill, John Y. Takekawa, C.J. Cardona, Joshua T. Ackerman, A.K. Schultz, K.A. Spragens, W.M. Boyce
2010, Avian Diseases (54) 426-432
We examined whether host traits influenced the occurrence of avian influenza virus (AIV) in Anatidae (ducks, geese, swans) at wintering sites in California's Central Valley. In total, 3487 individuals were sampled at Sacramento National Wildlife Refuge and Conaway Ranch Duck Club during the hunting season of 2007-08. Of the 19...