Skip to main content
U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Results

164399 results.

Alternate formats: RIS file of the first 3000 search results  |  Download all results as CSV | TSV | Excel  |  RSS feed based on this search  |  JSON version of this page of results

Page 6575, results 164351 - 164375

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
Predicting species distributions: unifying model selection and scale optimization for multi-scale occupancy models
Bryan S. Stevens, Courtney J. Conway
None, Ecosphere (10)
Geographic distributions are a basic component of a species’ ecology, and predicting distributions is a fundamental task of conservation and resource management. Reliable prediction depends on identification of appropriate scales of effect for environmental data, and scale-optimization techniques are thus desirable to identify optimal scales for predictor variables. Recent statistical...
Detecting sulfamethoxazole and carbamazepine in groundwater: Is ELISA a reliable screening tool?
Aliesha L. Krall, Sarah M. Elliott, Melinda L. Erickson, Byron A. Adams
None, Environmental Pollution (234) 420-428
In recent years, numerous studies have reported the prevalence of organic micropollutants in natural waters. There is an increasing interest in assessing the occurrence and transport of these contaminants in groundwater because a large number of people in the United States rely on groundwater for their drinking water. However, commonly used mass-spectrometry-based...
Characterizing the interface between wild ducks and poultry to evaluate the potential of transmission of avian pathogens
Julien Cappelle, Nicolas Gaidet, S. A. Iverson, John Y. Takekawa, Scott H. Newman, Bouba Fofana, Marius Gilbert
None, International Journal of Health Geographics (10)
BackgroundCharacterizing the interface between wild and domestic animal populations is increasingly recognized as essential in the context of emerging infectious diseases (EIDs) that are transmitted by wildlife. More specifically, the spatial and temporal distribution of contact rates between wild and domestic hosts is a key parameter for modeling...
Using indirect methods to constrain symbiotic nitrogen fixation rates: A case study from an Amazonian rain forest
C.C. Cleveland, B.Z. Houlton , C Neill, Sasha C. Reed, Y Wang, A.R. Townsend
None, Biogeochemistry (99) 1-13
Human activities have profoundly altered the global nitrogen (N) cycle. Increases in anthropogenic N have had multiple effects on the atmosphere, on terrestrial, freshwater and marine ecosystems, and even on human health. Unfortunately, methodological limitations challenge our ability to directly measure natural N inputs via biological N fixation (BNF)-the largest natural source...
Simulation of the long term radiometric responses of the Terra MODIS and EO-1 ALI using Hyperion spectral responses over Railroad Valley Playa in Nevada (RVPN)
Taeyoung Choi, Xiaoxiong Xiong, Amit Angal, Gyanesh Chander
None, Conference Paper, Proceedings of SPIE 7862, Earth observing missions and sensors: Development, implementation, and characterization
The Earth Observing-1 (EO-1) Hyperion instrument provides 220 spectral bands with wavelengths between 400 and 2500 nm at 30 m spatial resolution, which covers a 7.5 km by 100 km area on the ground. The EO-1 spacecraft has another multispectral sensor called the Advanced Land Imager (ALI), which has 10...
Silurian-Devonian age and tectonic setting of the Connecticut Valley-Gaspé trough of Vermont using U-Pb SHRIMP analyses of detrital zircons
C. K. McWilliams, Gregory J. Walsh, Robert P. Wintsch
None, American Journal of Science (310) 325-363
U-Pb SHRIMP ages of detrital zircons from metasedimentary rocks of the Connecticut Valley-Gaspe' trough in Vermont corroborate a Silurian-Devonian age of deposition for these strata and constrain their provenances. Ages of randomly selected detrital zircons obtained from quartzites within the Waits River and Gile Mountain Formations range from Archean to...
An empirical algorithm for estimating agricultural and riparian evapotranspiration using MODIS Enhanced Vegetation Index and ground measurements of ET. II. Application to the lower Colorado River, U.S.
R. Scott Murray, Pamela L. Nagler, Kiyomi Morino, Edward P. Glenn
None, Remote Sensing (1) 1125-1138
Large quantities of water are consumed by irrigated crops and riparian vegetation in western U.S. irrigation districts. Remote sensing methods for estimating evaporative water losses by soil and vegetation (evapotranspiration, ET) over wide river stretches are needed to allocate water for agricultural and environmental needs. We used the Enhanced Vegetation...
Synthesis of ground and remote sensing data for monitoring ecosystem functions in the Colorado River Delta, Mexico
Pamela L. Nagler, Edward P. Glenn, Osvel Hinojosa-Huera
None, Remote Sensing of Environment (113) 1473-1485
The delta of the Colorado River in Mexico supports a rich mix of estuarine, wetland and riparian ecosystems that provide habitat for over 350 species of birds as well as fish, marine mammals, and other wildlife. An important part of the delta ecosystem is the riparian corridor, which is supported by agricultural return flows and...
New approaches to stability analysis of steep coastal bluffs
Brian D. Collins, Nicholas Sitar
None, Conference Paper, Proceedings of geocongress 2008
We present a discussion on the limitations and needed improvements for existing slope stability analysis methods to accurately model steep coastal bluff failures resulting from both direct wave action at the toe in weakly cemented sands and precipitation-induced seepage failures in moderately cemented sands. Using a case-study detailing over 5...
Modeling of wave driven circulation and water quality in nearshore environments
Craig Jones, Stephen J. Angster
None, Conference Paper, Proceedings of the 2008 world environmental and water resources congress
In order to investigate the effects of nearshore discharges of water quality degrading substances and bacteria in coastal environments, models capable of predicting nearshore circulation due to local wave and tide conditions are required. One of the larger challenges to nearshore coastal modeling is accurately reproducing nearshore circulation due to...
Relationship between remotely-sensed vegetation indices, canopy attributes and plant physiological processes: What vegetation indices can and cannot tell us about the landscape
Edward P. Glenn, Alfredo R Huete, Pamela L. Nagler, Stephen G. Nelson
None, Sensors (8) 2136-2160
Vegetation indices (VIs) are among the oldest tools in remote sensing studies. Although many variations exist, most of them ratio the reflection of light in the red and NIR sections of the spectrum to separate the landscape into water, soil, and vegetation. Theoretical analyses and field studies have shown that...
Reconciling environmental and flood control goals on an arid-zone river: Case study of the Limitrophe Region of the lower Colorado River in the United States and Mexico
Edward P. Glenn, Kate Hucklebridge, Osvel Hinojosa-Huerta, Pamela L. Nagler, Jennifer Pitt
None, Environmental Management (41) 322-335
Arid zone rivers have highly variable flow rates, and flood control projects are needed to protect adjacent property from flood damage. On the other hand, riparian corridors provide important wildlife habitat, especially for birds, and riparian vegetation is adapted to the natural variability in flows on these rivers. While environmental...
Cross-borehole flow tests and insights into hydraulic connections in fractured mudstone and sandstone
John Williams, Pierre Lacombe, Carole D. Johnson, Frederick L. Paillet
None, Conference Paper, Symposium on the Application of Geophysics to Engineering and Environmental Problems
Cross-borehole flow tests provided insights into hydraulic connections in fractured and dipping mudstone and sandstone that were consistent with the lithostratigraphic and structural framework of a VOCcontaminated bedrock research site in west-central New Jersey. Two cross-borehole flow tests were completed. Each test involved measurement and analysis of transient flow in...
Comparative analysis of GPP products estimated from an empirical model and MODIS
Li Zhang, Bruce K. Wylie, Thomas Loveland, Lei Ji
None, Conference Paper, Global priorities in land remote sensing
Carbon-cycle models have uncertainties associated with data inputs, parameters, and model algorithms. The prerequisite for an applicable model is that it should perform at an acceptable level of accuracy and uncertainties should be documented. In this study, we validated the gross primary productivity (GPP) data from a piecewise regression (PWR)...
Characterizing the two-dimensional thermal conductivity distribution in a sand and gravel aquifer
Jeff M. Markle, Robert A. Schincariol, J.H. Sass, John W. Molson
None, Soil Science Society of America Journal (70) 1281-1294
Both hydrologic and thermal transport properties play a significant role in the movement of heat through permeable sedimentary material; however, the thermal conductivity is rarely characterized in detailed spatial resolution. As part of a study of the movement of thermal plumes through a sand and gravel aquifer, we have constructed...
Scouting craton’s edge in Paleo-Pacific Gondwana
Carol A. Finn, John W. Goodge, Detlef Damaske, C. Mark Fanning
Dieter Karl Futterer, Georg Kleinschmidt, Hubert Miller, Franz Tessensohn, editor(s)
None, Book chapter, Antarctica: Contributions to global earth sciences
The geology of the ice-covered interior of the East Antarctic shield is completely unknown; inferences about its composition and history are based on extrapolating scant outcrops from the coast inland. Although the shield is clearly composite in nature, a large part of its interior has been represented by a single...
Remnant damage from the 1906 San Francisco earthquake
John Boatwright
Carol S. Prentice, Judith G. Scotchmoor, Eldridge M. Moores, Jon P. Kiland, editor(s)
None, Book chapter, 1906 San Francisco earthquake centennial field guides: Field trips associated with the 100th Anniversary Conference, 18–23 April 2006, San Francisco, California
This field trip consists of two stops at locations where it is possible to see damage from the 1906 earthquake and to gauge the intensity of the ground shaking that caused the damage. The first stop is at a cemetery in Colma, where the damage to monuments and headstones was...
Development of stochastic modeling systems using deterministic models and GIS: Principles and a case study in the Atlantic Zone of Costa Rica
Shuguang Liu, William A. Reiners, Kenneth G. Gerow, David S Schimel, Michael Keller
None, Conference Paper
The most important requirements for large-area environmental modeling are a tight integration between models and data, and a close match of the spatial scale at which the model is developed with the scale at which the model is to be applied. To better match the scale of data with that...
Integrated geophysical characterization of the Winthrop Landfill Southern Flow Path, Winthrop, Maine
Cian B. Dawson, John W. Lane Jr., Eric A. White, Marcel Belaval
None, Conference Paper, Proceedings: Symposium on the application of geophysics to engineering and environmental problems
The U.S. Geological Survey (USGS), in cooperation with United Technologies Corporation, used an integrated suite of borehole, surface, and water-borne geophysical methods near the site of the former Winthrop Landfill, Winthrop, Maine, to investigate the hydrogeology controlling the transport of leachate from the landfill to nearby Annabessacook Lake. During the...