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Page 752, results 18776 - 18800

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Night sampling improves indices used for management of yellow perch in Lake Erie
P.M. Kocovsky, M.A. Stapanian, C.T. Knight
2010, Fisheries Management and Ecology (17) 10-18
Catch rate (catch per hour) was examined for age-0 and age-1 yellow perch, Perca flavescens (Mitchill), captured in bottom trawls from 1991 to 2005 in western Lake Erie: (1) to examine variation of catch rate among years, seasons, diel periods and their interactions; and (2) to determine whether sampling during...
Inherent Limitations of Hydraulic Tomography
Geoffrey C. Bohling, J.J. Butler
2010, Ground Water (48) 809-824
We offer a cautionary note in response to an increasing level of enthusiasm regarding high-resolution aquifer characterization with hydraulic tomography. We use synthetic examples based on two recent field experiments to demonstrate that a high degree of nonuniqueness remains in estimates of hydraulic parameter fields even when those estimates are...
Optimized autonomous space in-situ sensor web for volcano monitoring
W.-Z. Song, B. Shirazi, R. Huang, M. Xu, N. Peterson, R. LaHusen, J. Pallister, D. Dzurisin, S. Moran, M. Lisowski, S. Kedar, S. Chien, F. Webb, A. Kiely, J. Doubleday, A. Davies, D. Pieri
2010, IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing (3) 541-546
In response to NASA's announced requirement for Earth hazard monitoring sensor-web technology, a multidisciplinary team involving sensor-network experts (Washington State University), space scientists (JPL), and Earth scientists (USGS Cascade Volcano Observatory (CVO)), have developed a prototype of dynamic and scalable hazard monitoring sensor-web and applied it to volcano monitoring. The...
Prescribed fires as ecological surrogates for wildfires: A stream and riparian perspective
R.S. Arkle, D. S. Pilliod
2010, Forest Ecology and Management (259) 893-903
Forest managers use prescribed fire to reduce wildfire risk and to provide resource benefits, yet little information is available on whether prescribed fires can function as ecological surrogates for wildfire in fire-prone landscapes. Information on impacts and benefits of this management tool on stream and riparian ecosystems is particularly lacking....
On the application of multilevel modeling in environmental and ecological studies
Song S. Qian, Thomas F. Cuffney, Ibrahim Alameddine, Gerard McMahon, Kenneth H. Reckhow
2010, Ecology (91) 355-361
This paper illustrates the advantages of a multilevel/hierarchical approach for predictive modeling, including flexibility of model formulation, explicitly accounting for hierarchical structure in the data, and the ability to predict the outcome of new cases. As a generalization of the classical approach, the multilevel modeling approach explicitly models the hierarchical...
Exploring the limits of identifying sub-pixel thermal features using ASTER TIR data
R. Greg Vaughan, Laszlo P. Keszthelyi, Ashley G. Davies, David J. Schneider, Cheryl Jaworowski, Henry Heasler
2010, Journal of Volcanology and Geothermal Research (189) 225-237
Understanding the characteristics of volcanic thermal emissions and how they change with time is important for forecasting and monitoring volcanic activity and potential hazards. Satellite instruments view volcanic thermal features across the globe at various temporal and spatial resolutions. Thermal features that may be a precursor to a major eruption,...
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...
Teaching citizen science skills online: Implications for invasive species training programs
G. Newman, A. Crall, M. Laituri, J. Graham, T. Stohlgren, J.C. Moore, K. Kodrich, K.A. Holfelder
2010, Applied Environmental Education and Communication (9) 276-286
Citizen science programs are emerging as an efficient way to increase data collection and help monitor invasive species. Effective invasive species monitoring requires rigid data quality assurances if expensive control efforts are to be guided by volunteer data. To achieve data quality, effective online training is needed to improve field...
Model selection bias and Freedman's paradox
P.M. Lukacs, K.P. Burnham, David R. Anderson
2010, Annals of the Institute of Statistical Mathematics (62) 117-125
In situations where limited knowledge of a system exists and the ratio of data points to variables is small, variable selection methods can often be misleading. Freedman (Am Stat 37:152-155, 1983) demonstrated how common it is to select completely unrelated variables as highly "significant" when the number of data points...
Climatic water deficit, tree species ranges, and climate change in Yosemite National Park
James A. Lutz, Jan W. Van Wagtendonk, Jerry F. Franklin
2010, Journal of Biogeography (37) 936-350
Aim (1) To calculate annual potential evapotranspiration (PET), actual evapotranspiration (AET) and climatic water deficit (Deficit) with high spatial resolution; (2) to describe distributions for 17 tree species over a 2300-m elevation gradient in a 3000-km2 landscape relative to AET and Deficit; (3) to examine changes in AET and Deficit...
Silica-rich deposits and hydrated minerals at Gusev Crater, Mars: Vis-NIR spectral characterization and regional mapping
M.S. Rice, J.F. Bell III, E.A. Cloutis, A. Wang, S. W. Ruff, M.A. Craig, D.T. Bailey, J. R. Johnson, P.A. De Souza Jr., W. H. Farrand
2010, Icarus (205) 375-395
The Mars Exploration Rover (MER) Spirit has discovered surprisingly high concentrations of amorphous silica in soil and nodular outcrops in the Inner Basin of the Columbia Hills. In Pancam multispectral observations, we find that an absorption feature at the longest Pancam wavelength (1009 nm) appears to be characteristic of these...
Geology and undiscovered oil and gas resources in the Madison Group, Williston Basin, North Dakota and Montana
Stephanie B. Gaswirth, Paul G. Lillis, Richard M. Pollastro, Lawrence O. Anna
2010, Mountain Geologist (47) 71-80
Two of the total petroleum systems (TPS) defined as part of the U.S. Geological Survey (USGS) assessment of the Williston Basin contain Mississippian Madison Group strata: 1) the Bakken-Lodgepole TPS, which includes the Lodgepole Formation; and 2) the Madison TPS, which includes the Mission Canyon, Charles, and Spearfish formations. The...
Sedimentary basins reconnaissance using the magnetic Tilt-Depth method
A. Salem, S. Williams, E. Samson, D. Fairhead, D. Ravat, R.J. Blakely
2010, Exploration Geophysics (41) 198-209
We compute the depth to the top of magnetic basement using the Tilt-Depth method from the best available magnetic anomaly grids covering the continental USA and Australia. For the USA, the Tilt-Depth estimates were compared with sediment thicknesses based on drilling data and show a correlation of 0.86 between the...
Modeling fire severity in black spruce stands in the Alaskan boreal forest using spectral and non-spectral geospatial data
Kirsten M. Barrett, E.S. Kasischke, A. D. McGuire, M.R. Turetsky, E.S. Kane
2010, Remote Sensing of Environment (114) 1494-1503
Biomass burning in the Alaskan interior is already a major disturbance and source of carbon emissions, and is likely to increase in response to the warming and drying predicted for the future climate. In addition to quantifying changes to the spatial and temporal patterns of burned areas, observing variations in...
Irrigated areas of India derived using MODIS 500 m time series for the years 2001-2003
V. Dheeravath, P.S. Thenkabail, G. Chandrakantha, P. Noojipady, G.P.O. Reddy, C.M. Biradar, M.K. Gumma, M. Velpuri
2010, ISPRS Journal of Photogrammetry and Remote Sensing (65) 42-59
The overarching goal of this research was to develop methods and protocols for mapping irrigated areas using a Moderate Resolution Imaging Spectroradiometer (MODIS) 500 m time series, to generate irrigated area statistics, and to compare these with ground- and census-based statistics. The primary mega-file data-cube (MFDC), comparable to a hyper-spectral...
GIS-based spatial regression and prediction of water quality in river networks: A case study in Iowa
X. Yang, W. Jin
2010, Journal of Environmental Management (91) 1943-1951
Nonpoint source pollution is the leading cause of the U.S.'s water quality problems. One important component of nonpoint source pollution control is an understanding of what and how watershed-scale conditions influence ambient water quality. This paper investigated the use of spatial regression to evaluate the impacts of watershed characteristics on...
Sap flux-scaled transpiration by tamarisk (Tamarix spp.) before, during and after episodic defoliation by the saltcedar leaf beetle (Diorhabda carinulata)
K. R. Hultine, P.L. Nagler, K. Morino, S.E. Bush, K.G. Burtch, P.E. Dennison, E. P. Glenn, J.R. Ehleringer
2010, Agricultural and Forest Meteorology (150) 1467-1475
The release of the saltcedar beetle (Diorhabda carinulata) has resulted in the periodic defoliation of tamarisk (Tamarix spp.) along more than 1000 river km in the upper Colorado River Basin and is expected to spread along many other river reaches throughout the upper basin, and possibly into the lower Colorado...
Establishing the Antarctic Dome C community reference standard site towards consistent measurements from Earth observation satellites
C. Cao, S. Uprety, J. Xiong, A. Wu, P. Jing, D. Smith, G. Chander, N. Fox, S. Ungar
2010, Canadian Journal of Remote Sensing (36) 498-513
Establishing satellite measurement consistency by using common desert sites has become increasingly more important not only for climate change detection but also for quantitative retrievals of geophysical variables in satellite applications. Using the Antarctic Dome C site (75°06′S, 123°21′E, elevation 3.2 km) for satellite radiometric calibration and validation (Cal/Val) is...
Physical Habitat Characteristics on the North Fork Shenandoah River, VA in 2002-2003
Jennifer L. Krstolic, Donald C. Hayes, Peter M. Ruhl
2010, Report
This dataset was collected with a PLGR government-issue GPS, and through manual measurement in the field. Points were gathered while canoeing along the North Fork Shenandoah River. Each location marked a change in meso-scale habitat type. GPS points were supplemented with GIS-derived points in areas where manual...
Molecular investigations into a globally important carbon pool: Permafrost-protected carbon in Alaskan soils
M. P. Waldrop, K.P. Wickland, Rickie White, A.A. Berhe, J.W. Harden, V.E. Romanovsky
2010, Global Change Biology (16) 2543-2554
The fate of carbon (C) contained within permafrost in boreal forest environments is an important consideration for the current and future carbon cycle as soils warm in northern latitudes. Currently, little is known about the microbiology or chemistry of permafrost soils that may affect its decomposition once soils thaw. We...