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Page 2133, results 53301 - 53325

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A simulation/optimization model for groundwater resources management in the Afram Plains area, Ghana
S.M. Yidana
2008, Journal of Environmental Hydrology (16) 1-14
A groundwater flow simulation model was developed using available hydrogeo logical data to A groundwater flow simulation model was developed using available hydrogeological data to describe groundwater flow in the Afram Plains area. A nonlinear optimization model was then developed and solved for the management of groundwater resources to meet...
Impact of the newly arrived seed-predating beetle Specularius impressithorax (Coleoptera: Chrysomelidae: Bruchinae) in Hawai'i
A.C. Medeiros, E. Von Allmen, M. Fukada, A. Samuelson, T. Lau
2008, Pacific Conservation Biology (14) 7-12
Prior to 2001, seed predation was virtually absent in the endemic Wiliwili Erythrina sandwicensis (Fabaceae: Degener), dominant tree species of lower-elevation Hawaiian dryland forests. The African bruchine chrysomelid Specularius impressithorax (Pic) (Coleoptera: Chrysomelidae: Bruchinae) was first detected in Hawai'i in 2001 and became established on all main islands within the...
A lightweight sensor network management system design
F. Yuan, W.-Z. Song, N. Peterson, Y. Peng, L. Wang, B. Shirazi, R. LaHusen
2008, Conference Paper, 6th Annual IEEE International Conference on Pervasive Computing and Communications, PerCom 2008
In this paper, we propose a lightweight and transparent management framework for TinyOS sensor networks, called L-SNMS, which minimizes the overhead of management functions, including memory usage overhead, network traffic overhead, and integration overhead. We accomplish this by making L-SNMS virtually transparent to other applications hence requiring minimal integration. The...
Turning population trend monitoring into active conservation: Can we save the cascades frog (Rang cascadae) in the Lassen Region of California?
G. M. Fellers, K.L. Pope, J.E. Stead, M.S. Koo, W.H. Welsh Jr.
2008, Herpetological Conservation and Biology (3) 28-39
Monitoring the distribution, population size, and trends of declining species is necessary to evaluate their vulnerability to extinction. It is the responsibility of scientists to alert management professionals of the need for preemptive action if a species approaches imminent, regional extirpation. This is the case with Rana cascadae (Cascades Frog)...
Environmental occurrence and shallow ground water detection of the antibiotic monensin from dairy farms
N. Watanabe, T.H. Harter, B.A. Bergamaschi
2008, Conference Paper, Journal of Environmental Quality
Pharmaceuticals used in animal feeding operations have been detected in various environmental settings. There is a growing concern about the impact on terrestrial and aquatic organisms and the development of antibiotic-resistant strains of microorganisms. Pharmaceutical use in milking cows is relatively limited compared with other livestock operations, except for the...
Optimized Autonomous Space In-situ Sensor-Web for volcano monitoring
W.-Z. Song, B. Shirazi, S. Kedar, S. Chien, F. Webb, D. Tran, A. Davis, D. Pieri, R. LaHusen, J. Pallister, D. Dzurisin, S. Moran, M. Lisowski
2008, Conference Paper, IEEE Aerospace Conference Proceedings
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)), is developing a prototype dynamic and scaleable hazard monitoring sensor-web and applying it to volcano monitoring. The combined...
Decadal-scale changes of pesticides in ground water of the United States, 1993-2003
L. M. Bexfield
2008, Conference Paper, Journal of Environmental Quality
Pesticide data for ground water sampled across the United States between 1993-1995 and 2001-2003 by the U.S. Geological Survey National Water-Quality Assessment Program were evaluated for trends in detection frequency and concentration. The data analysis evaluated samples collected from a total of 362 wells located in 12 local well networks...
Temporal trends in nitrate and selected pesticides in mid-atlantic ground water
L.M. Debrewer, S.W. Ator, J. M. Denver
2008, Conference Paper, Journal of Environmental Quality
Evaluating long-term temporal trends in regional ground-water quality is complicated by variable hydrogeologic conditions and typically slow flow, and such trends have rarely been directly measured. Ground-water samples were collected over near-decadal and annual intervals from unconfined aquifers in agricultural areas of the Mid-Atlantic region, including fractured carbonate rocks in...
Semantic mediation in the national geologic map database (US)
D. Percy, S. Richard, D. Soller
2008, Conference Paper, AAAI Spring Symposium - Technical Report
Controlled language is the primary challenge in merging heterogeneous databases of geologic information. Each agency or organization produces databases with different schema, and different terminology for describing the objects within. In order to make some progress toward merging these databases using current technology, we have developed software and a workflow...
Radiometric cross-calibration of the Terra MODIS and Landsat 7 ETM+ using an invariant desert site
T. Choi, A. Angal, G. Chander, X. Xiong
2008, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
A methodology for long-term radiometric cross-calibration between the Terra Moderate Resolution Imaging Spectroradiometer (MODIS) and Landsat 7 (L7) Enhanced Thematic Mapper Plus (ETM+) sensors was developed. The approach involves calibration of near-simultaneous surface observations between 2000 and 2007. Fifty-seven cloud-free image pairs were carefully selected over the Libyan desert for...
Development of landsat-5 thematic mapper internal calibrator gain and offset table
J. A. Barsi, G. Chander, E. Micijevic, B. L. Markham, Md. O. Haque
2008, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
The National Landsat Archive Production System (NLAPS) has been the primary processing system for Landsat data since U.S. Geological Survey (USGS) Earth Resources Observation and Science Center (EROS) started archiving Landsat data. NLAPS converts raw satellite data into radiometrically and geometrically calibrated products. NLAPS has historically used the Internal Calibrator...
L5 TM radiometric recalibration procedure using the internal calibration trends from the NLAPS trending database
G. Chander, Md. O. Haque, E. Micijevic, J. A. Barsi
2008, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
From the Landsat program's inception in 1972 to the present, the earth science user community has benefited from a historical record of remotely sensed data. The multispectral data from the Landsat 5 (L5) Thematic Mapper (TM) sensor provide the backbone for this extensive archive. Historically, the radiometric calibration procedure for...
Monitoring programs to assess reintroduction efforts: A critical component in recovery
E. Muths, V. Dreitz
2008, Animal Biodiversity and Conservation (31) 47-56
Reintroduction is a powerful tool in our conservation toolbox. However, the necessary follow-up, i.e. long-term monitoring, is not commonplace and if instituted may lack rigor. We contend that valid monitoring is possible, even with sparse data. We present a means to monitor based on demographic data and a projection model...
Decadal-scale changes of nitrate in ground water of the United States, 1988-2004
Michael G. Rupert
2008, Journal of Environmental Quality (37) S240-S248
This study evaluated decadal-scale changes of nitrate concentrations in groundwater samples collected by the USGS National Water-Quality Assessment Program from 495 wells in 24 well networks across the USA in predominantly agricultural areas. Each well network was sampled once during 1988-1995 and resampled once during 2000-2004. Statistical tests of decadal-scale...
MODIS and SeaWIFS on-orbit lunar calibration
Jielun Sun, R.E. Eplee Jr., X. Xiong, T. Stone, G. Meister, C.R. McClain
2008, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
The Moon plays an important role in the radiometric stability monitoring of the NASA Earth Observing System's (EOS) remote sensors. The MODIS and SeaWIFS are two of the key instruments for NASA's EOS missions. The MODIS Protoflight Model (PFM) on-board the Terra spacecraft and the MODIS Flight Model 1 (FM1)...
Radiometric calibration stability and inter-calibration of solar-band instruments in orbit using the moon
T.C. Stone
2008, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
With the increased emphasis on monitoring the Earth's climate from space, more stringent calibration requirements are being placed on the data products from remote sensing satellite instruments. Among these are stability over decade-length time scales and consistency across sensors and platforms. For radiometer instruments in the solar reflectance wavelength range...
Trends of pesticides and nitrate in ground water of the Central Columbia Plateau, Washington, 1993-2003
L. Frans
2008, Conference Paper, Journal of Environmental Quality
Pesticide and nitrate data for ground water sampled in the Central Columbia Plateau, Washington, between 1993 and 2003 by the U.S. Geological Survey National Water-Quality Assessment Program were evaluated for trends in concentration. A total of 72 wells were sampled in 1993-1995 and again in 2002-2003 in three well networks...
M-log A observations for recent large earthquakes
Thomas C. Hanks, W. H. Bakun
2008, Bulletin of the Seismological Society of America (98) 490-494
Using a magnitude (M)-log area (A) dataset augmented with seven large (M > 7.0) earthquakes occurring since Wells and Coppersmith (1994), this short note assesses the current validity of the bilinear M-log A relations for continental, strike-slip earthquakes proposed by Hanks and Bakun (2002), in particular the L-model scaling at...
Transport of water, carbon, and sediment through the Yukon River Basin
Timothy P. Brabets, Paul F. Schuster
2008, Fact Sheet 2008-3005
In 2001, the U.S. Geological Survey (USGS) began a water-quality study of the Yukon River. The Yukon River Basin (YRB), which encompasses 330,000 square miles in northwestern Canada and central Alaska (fig. 1), is one of the largest and most diverse ecosystems in North America. The Yukon River is more...
Assessing the feasibility of native fish reintroductions: a framework and example applied to bull trout in the Clackamas River, Oregon
Jason B. Dunham, Kirsten Gallo
2008, Open-File Report 2008-1007
In a species conservation context, translocations can be an important tool, but they frequently fail to successfully establish new populations. We consider the case of reintroductions for bull trout (Salvelinus confluentus), a federally-listed threatened species with a widespread but declining distribution in western North America. Our specific objectives in this...
Are hotspots of evolutionary potential adequately protected in southern California?
Amy G. Vandergast, A.J. Bohonak, S.A. Hathaway, J. Boys, Robert N. Fisher
2008, Biological Conservation (141) 1648-1664
Reserves are often designed to protect rare habitats, or "typical" exemplars of ecoregions and geomorphic provinces. This approach focuses on current patterns of organismal and ecosystem-level biodiversity, but typically ignores the evolutionary processes that control the gain and loss of biodiversity at these and other levels (e.g., genetic, ecological). In...
A Visual Basic program to plot sediment grain-size data on ternary diagrams
L. J. Poppe, A.H. Eliason
2008, Computers & Geosciences (34) 561-565
Sedimentologic datasets are typically large and compiled into tables or databases, but pure numerical information can be difficult to understand and interpret. Thus, scientists commonly use graphical representations to reduce complexities, recognize trends and patterns in the data, and develop hypotheses. Of the graphical techniques, one of the most...
A Key to the Pupal Exuviae of the Midges (Diptera: Chironomidae) of Everglades National Park, Florida
Robert E. Jacobsen
2008, Scientific Investigations Report 2008-5082
A key has been developed for identifying the pupal exuviae of 132 taxa of chironomid midges collected in Everglades National Park, as well as 18 additional species from freshwater habitats adjacent to the Park. Descriptions and illustrations are based upon voucher specimens from extensive collections of chironomid pupal exuviae for...
Herpetological Monitoring Using a Pitfall Trapping Design in Southern California
Robert Fisher, Drew Stokes, Carlton Rochester, Cheryl Brehme, Stacie Hathaway, Ted Case
2008, Techniques and Methods 2-A5
The steps necessary to conduct a pitfall trapping survey for small terrestrial vertebrates are presented. Descriptions of the materials needed and the methods to build trapping equipment from raw materials are discussed. Recommended data collection techniques are given along with suggested data fields. Animal specimen processing procedures, including toe- and...