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Page 1929, results 48201 - 48225

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Not all publications have extents, not all extents are completely accurate
Impacts of hikers on aquatic invertebrates in the North Fork of the Virgin River, Utah
A.M. Caires, M.R. Vinson, A.M.D. Brasher
2010, Southwestern Naturalist (55) 551-557
Effects of in-stream hiking on benthic standing stocks and drifting aquatic invertebrates and on organic matter were examined in the North Fork of the Virgin River, Zion National Park, Washington County, Utah. Densities of drifting aquatic invertebrates and organic matter increased with increasing numbers of hikers and reached a threshold...
Variation in Lake Michigan alewife (Alosa pseudoharengus) thiaminase and fatty acids composition
Dale C. Honeyfield, Donald E. Tillitt, John D. Fitzsimons, Scott B. Brown
2010, Journal of Freshwater Ecology (25) 65-71
Thiaminase activity of alewife (Alosa pseudoharengus) is variable across Lake Michigan, yet factors that contribute to the variability in alewife thiaminase activity are unknown. The fatty acid content of Lake Michigan alewife has not been previously reported. Analysis of 53 Lake Michigan alewives found a positive correlation between thiaminase activity...
The 2009 Samoa-Tonga great earthquake triggered doublet
T. Lay, C.J. Ammon, H. Kanamori, L. Rivera, K.D. Koper, Alexander R. Hutko
2010, Nature (466) 964-968
Great earthquakes (having seismic magnitudes of at least 8) usually involve abrupt sliding of rock masses at a boundary between tectonic plates. Such interplate ruptures produce dynamic and static stress changes that can activate nearby intraplate aftershocks, as is commonly observed in the trench-slope region seaward of a great subduction...
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...
Lake temperature and ice cover regimes in the Alaskan Subarctic and Arctic: Integrated monitoring, remote sensing, and modeling
C.D. Arp, Benjamin M. Jones, Matthew Whitman, A. Larsen, F.E. Urban
2010, Journal of the American Water Resources Association (46) 777-791
Lake surface regimes are fundamental attributes of lake ecosystems and their interaction with the land and atmosphere. High latitudes may be particularly sensitive to climate change, however, adequate baselines for these lakes are often lacking. In this study, we couple monitoring, remote sensing, and modeling techniques to generate baseline datasets...
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...
Updating the 2001 National Land Cover Database Impervious Surface Products to 2006 using Landsat imagery change detection methods
George Xian, Collin G. Homer
2010, Remote Sensing of Environment (114) 1676-1686
A prototype method was developed to update the U.S. Geological Survey (USGS) National Land Cover Database (NLCD) 2001 to a nominal date of 2006. NLCD 2001 is widely used as a baseline for national land cover and impervious cover conditions. To enable the updating of this database in an optimal...
Canopy gap dynamics of second-growth red spruce-northern hardwood stands in West Virginia
J.S. Rentch, T.M. Schuler, G.J. Nowacki, N.R. Beane, W.M. Ford
2010, Forest Ecology and Management (260) 1921-1929
Forest restoration requires an understanding of the natural disturbance regime of the target community and estimates of the historic range of variability of ecosystem components (composition, structure, and disturbance processes). Management prescriptions that support specific restoration activities should be consistent with these parameters. In this study, we describe gap-phase dynamics...
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...
Habitat suitability and conservation of the Giant Gartersnake (Thamnophis gigas) in the Sacramento Valley of California
B.J. Halstead, G.D. Wylie, Michael L. Casazza
2010, Copeia 591-599
Resource managers often have little information regarding the habitat requirements and distribution of rare species. Factor analysis-based habitat suitability models describe the ecological niche of a species and identify locations where these conditions occur on the landscape using existing occurrence data. We used factor analyses to assess the suitability of...
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...
Inter-regional comparison of land-use effects on stream metabolism
M. J. Bernot, D. J. Sobota, R.O. Hall, P. J. Mulholland, W. K. Dodds, J.R. Webster, J. L. Tank, L. R. Ashkenas, L. W. Cooper, Clifford N. Dahm, S.V. Gregory, N. B. Grimm, S. K. Hamilton, S. L. Johnson, W. H. McDowell, J.L. Meyer, B. Peterson, G. C. Poole, Valett H.M. Maurice, C. Arango, J. J. Beaulieu, A. J. Burgin, C. Crenshaw, A. M. Helton, L. Johnson, J. Merriam, B.R. Niederlehner, J. M. O’Brien, J. D. Potter, R.W. Sheibley, S. M. Thomas, K. Wilson
2010, Freshwater Biology (55) 1874-1890
1. Rates of whole-system metabolism (production and respiration) are fundamental indicators of ecosystem structure and function. Although first-order, proximal controls are well understood, assessments of the interactions between proximal controls and distal controls, such as land use and geographic region, are lacking. Thus, the influence of land use on stream...
Building the IOOS data management subsystem
J. de La Beaujardière, R. Mendelssohn, C. Ortiz, R. Signell
2010, Marine Technology Society Journal (44) 73-83
We discuss progress to date and plans for the Integrated Ocean Observing System (IOOS??) Data Management and Communications (DMAC) subsystem. We begin by presenting a conceptual architecture of IOOS DMAC. We describe work done as part of a 3-year pilot project known as the Data Integration Framework and the subsequent...
Design and analysis of simple choice surveys for natural resource management
John Fieberg, Louis Cornicelli, David C. Fulton, Marrett D. Grund
2010, Journal of Wildlife Management (74) 871-879
We used a simple yet powerful method for judging public support for management actions from randomized surveys. We asked respondents to rank choices (representing management regulations under consideration) according to their preference, and we then used discrete choice models to estimate probability of choosing among options (conditional on the set...
Mineral resource of the Month: Clay
Robert L. Virta
2010, Earth (2010) 27-27
Clays were one of the first mineral commodities used by people. Clay pottery has been found in archeological sites that are 12,000 years old, and clay figurines have been found in sites that are even older....
Ninespine Stickleback Abundance in Lake Michigan Increases After Dreissenid Mussel Invasion
Charles P. Madenjian, David B. Bunnell, Owen T. Gorman
2010, Transactions of the American Fisheries Society (139) 11-20
Based on data from our annual lakewide bottom trawl survey of Lake Michigan, we determined that density of ninespine sticklebacks Pungitius pungitius increased from an average of 0.234 kg/ha during 1973–1995 to an average of 1.318 kg/ha during 1996–2007. This greater-than-fivefold increase in density coincided with the dreissenid mussel invasion...
Effects of natural-channel-design restoration on habitat quality in Catskill Mountain streams, New York
Anne G. Ernst, Barry P. Baldigo, Christiane Mulvihill, Mark Vian
2010, Transactions of the American Fisheries Society (139) 468-482
Stream restoration has received much attention in recent years, yet there has been little effort to evaluate its impacts on physical habitat, stability, and biota. A popular but controversial stream restoration approach is natural channel design (NCD), which cannot be adequately evaluated without a long-term, independent assessment of its effects...
Variable responses of fish assemblages, habitat, and stability to natural-channel-design restoration in Catskill Mountain streams
Barry P. Baldigo, Anne G. Ernst, Dana R. Warren, Sarah J. Miller
2010, Transactions of the American Fisheries Society (139) 449-467
Natural-channel-design (NCD) restorations were recently implemented within large segments of five first- and second-order streams in the Catskill Mountains of New York in an attempt to increase channel stability, reduce bed and bank erosion, and sustain water quality. In conjunction with these efforts, 54 fish and habitat surveys were done...
Analyzing debris flows with the statistically calibrated empirical model LAHARZ in southeastern Arizona, USA
Christopher S. Magirl, Peter G. Griffiths, Robert H. Webb
2010, Geomorphology (119) 111-124
Hazard-zone delineation for extreme events is essential for floodplain management near mountain fronts in arid and semiarid regions. On 31 July 2006, unprecedented debris flows occurred in the Santa Catalina Mountains of southeastern Arizona following extreme multiday precipitation (recurrence interval > 1000 years for 4-day precipitation). Most mobilized sediment contributing to debris...
Response to the comment by Henry Kahn and Dennis Santella on a summary of the development of a signature for detection of residual dust from the collapse of the World Trade Center buildings
Gregory P. Meeker, Heather Lowers, Paul J. Lioy, Morton Lippmann
2010, Journal of Exposure Science and Environmental Epidemiology (20) 491-492
A response by Gregory P. Meeker and colleagues to a commentary on their article on the development of a signature for detection of residual dust from the collapse of the World Trade Center buildings is presented...
Passive seismic monitoring of natural and induced earthquakes: Case studies, future directions and socio-economic relevance
Marco Bohnhoff, Georg Dresen, William L. Ellsworth, Hisao Ito
Sierd Cloetingh, Jorg Negendank, editor(s)
2010, Book chapter, New frontiers in integrated solid earth sciences
An important discovery in crustal mechanics has been that the Earth’s crust is commonly stressed close to failure, even in tectonically quiet areas. As a result, small natural or man-made perturbations to the local stress field may trigger earthquakes. To understand these processes, Passive Seismic Monitoring (PSM) with seismometer arrays...
Growth, carbon-isotope discrimination, and drought-associated mortality across a Pinus ponderosa elevational transect
N.G. McDowell, Craig D. Allen, L. Marshall
2010, Global Change Biology (16) 399-415
Drought- and insect-associated tree mortality at low-elevation ecotones is a widespread phenomenon but the underlying mechanisms are uncertain. Enhanced growth sensitivity to climate is widely observed among trees that die, indicating that a predisposing physiological mechanism(s) underlies tree mortality. We tested three, linked hypotheses regarding mortality using a ponderosa pine...