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Full-Text Articles in Other Environmental Sciences

Coastal Development And Precipitation Drive Pathogen Flow From Land To Sea: Evidence From A Toxoplasma Gondii And Felid Host System, Elizabeth Vanwormer, Tim E. Carpenter, Purnendu Singh, Karen Shapiro, Wesley W. Wallender, Patricia A. Conrad, John L. Largier, Marco P. Maneta, Jonna A. K. Mazet Jan 2016

Coastal Development And Precipitation Drive Pathogen Flow From Land To Sea: Evidence From A Toxoplasma Gondii And Felid Host System, Elizabeth Vanwormer, Tim E. Carpenter, Purnendu Singh, Karen Shapiro, Wesley W. Wallender, Patricia A. Conrad, John L. Largier, Marco P. Maneta, Jonna A. K. Mazet

School of Natural Resources: Faculty Publications

Rapidly developing coastal regions face consequences of land use and climate change including flooding and increased sediment, nutrient, and chemical runoff, but these forces may also enhance pathogen runoff, which threatens human, animal, and ecosystem health. Using the zoonotic parasite Toxoplasma gondii in California, USA as a model for coastal pathogen pollution, we examine the spatial distribution of parasite runoff and the impacts of precipitation and development on projected pathogen delivery to the ocean. Oocysts, the extremely hardy free-living environmental stage of T. gondii shed in faeces of domestic and wild felids, are carried to the ocean by freshwater runoff. …


Alpha-Lipoic Acid Supplementation Protects Enzymes From Damage By Nitrosative And Oxidative Stress, Sylvia Hiller, Robert Dekroon, Eric D. Hamlett, Longquan Xu, Cristina Osorio, Jennifer Robinette, Witold Winnik, Stephen Simington, Nobuyo Maeda, Oscar Alzate, Xianwen Yi Jan 2016

Alpha-Lipoic Acid Supplementation Protects Enzymes From Damage By Nitrosative And Oxidative Stress, Sylvia Hiller, Robert Dekroon, Eric D. Hamlett, Longquan Xu, Cristina Osorio, Jennifer Robinette, Witold Winnik, Stephen Simington, Nobuyo Maeda, Oscar Alzate, Xianwen Yi

United States Environmental Protection Agency: Publications

Background: S-nitrosylation of mitochondrial enzymes involved in energy transfer under nitrosative stress may result in ATP deficiency. We investigated whether α-lipoic acid, a powerful antioxidant, could alleviate nitrosative stress by regulating S-nitrosylation,which could result in retaining themitochondrial enzyme activity.

Methods: In this study, we have identified the S-nitrosylated forms of subunit 1 of dihydrolipoyllysine succinyltransferase (complex III), and subunit 2 of the α-ketoglutarate dehydrogenase complex by implementing a fluorescence-based differential quantitative proteomics method.

Results: We found that the activities of these two mitochondrial enzymes were partially but reversibly inhibited by S-nitrosylation in cultured endothelial cells, and that their activities …


Estimating Ozone And Secondary Pm2.5 Impacts From Hypothetical Single Source Emissions In The Central And Eastern United States, Kirk R. Baker, Robert A. Kotchenruther, Rynda C. Hudman Jan 2016

Estimating Ozone And Secondary Pm2.5 Impacts From Hypothetical Single Source Emissions In The Central And Eastern United States, Kirk R. Baker, Robert A. Kotchenruther, Rynda C. Hudman

United States Environmental Protection Agency: Publications

Secondary pollutant impacts from emissions of single sources may need to be assessed to satisfy a variety of regulatory requirements including the Clean Air Act New Source Review and Prevention of Significant Deterioration programs and the National Environmental Policy Act. In this work, single source impacts on O3 and secondary PM2.5 are estimated with annual 2011 photochemical grid model simulations where new hypothetical sources are added to the central and eastern United States with varying precursor emission rates and emission release heights. Impacts from these hypothetical sources are tracked with photochemical grid model source apportionment. Single source impacts …


Seasonality Of Coliform Bacteria Detection Rates In New Jersey Domestic Wells, Thomas B. Atherholt, Nicholas A. Procopio, Sandra M. Goodrow Jan 2016

Seasonality Of Coliform Bacteria Detection Rates In New Jersey Domestic Wells, Thomas B. Atherholt, Nicholas A. Procopio, Sandra M. Goodrow

United States Environmental Protection Agency: Publications

It is important that indicators of fecal pollution are reliable. Coliform bacteria are a commonly used indicator of fecal pollution. As other investigators have reported elsewhere, we observed a seasonal pattern of coliform bacteria detections in domestic wells in New Jersey. Examination of a statewide database of 10 years of water quality data from 93,447 samples, from 78,207 wells, generated during real estate transactions, revealed that coliform bacteria were detected in a higher proportion of wells during warm weather months. Further examination of the seasonal pattern of other data, including well water pH, precipitation, ground and surface water temperatures, surface …


Temporal Trends In The Spatial Distribution Of Impervious Cover Relative To Stream Location, J. Wickham, A. Neale, M. Mehaffey, T. Jarnagin, D. Norton Jan 2016

Temporal Trends In The Spatial Distribution Of Impervious Cover Relative To Stream Location, J. Wickham, A. Neale, M. Mehaffey, T. Jarnagin, D. Norton

United States Environmental Protection Agency: Publications

Use of impervious cover is transitioning from an indicator of surface water condition to one that also guides and informs watershed planning and management, including Clean Water Act (33 U.S.C. §1251 et seq.) reporting. Whether it is for understanding surface water condition or planning and management, impervious cover is most commonly expressed as summary measurement (e.g., percentage watershed in impervious cover). We use the National Land Cover Database to estimate impervious cover in the vicinity of surface waters for three time periods (2001, 2006, 2011). We also compare impervious cover in the vicinity of surface waters to watershed summary estimates …


Cyanotoxins In Inland Lakes Of The United States: Occurrence And Potential Recreational Health Risks In The Epa National Lakes Assessment 2007, Keith A. Loftin, Jennifer L. Graham, Elizabeth D. Hillborn, Sarah C. Lehmann, Michael T. Meyer, Julie E. Dietze, Christopher B. Griffith Jan 2016

Cyanotoxins In Inland Lakes Of The United States: Occurrence And Potential Recreational Health Risks In The Epa National Lakes Assessment 2007, Keith A. Loftin, Jennifer L. Graham, Elizabeth D. Hillborn, Sarah C. Lehmann, Michael T. Meyer, Julie E. Dietze, Christopher B. Griffith

United States Environmental Protection Agency: Publications

A large nation-wide survey of cyanotoxins (1161 lakes) in the United States (U.S.) was conducted during the EPA National Lakes Assessment 2007. Cyanotoxin data were compared with cyanobacteria abundance- and chlorophyll-based World Health Organization (WHO) thresholds and mouse toxicity data to evaluate potential recreational risks. Cylindrospermopsins, microcystins, and saxitoxins were detected (ELISA) in 4.0, 32, and 7.7% of samples with mean concentrations of 0.56, 3.0, and 0.061 mg/L, respectively (detections only). Co-occurrence of the three cyanotoxin classes was rare (0.32%) when at least one toxin was detected. Cyanobacteria were present and dominant in 98 and 76% of samples, respectively. Potential …


Carbon Storage In Us Wetlands, A. M. Nahlik, M. S. Fennessy Jan 2016

Carbon Storage In Us Wetlands, A. M. Nahlik, M. S. Fennessy

United States Environmental Protection Agency: Publications

Wetland soils contain some of the highest stores of soil carbon in the biosphere. However, there is little understanding of the quantity and distribution of carbon stored in our remaining wetlands or of the potential effects of human disturbance on these stocks. Here we use field data from the 2011 National Wetland Condition Assessment to provide unbiased estimates of soil carbon stocks for wetlands at regional and national scales. We find that wetlands in the conterminous United States store a total of 11.52 PgC, much of which is within soils deeper than 30 cm. Freshwater inland wetlands, in part due …


In-Air Hearing Of A Diving Duck: A Comparison Of Psychoacoustic And Auditory Brainstem Response Thresholds, Sara E. Crowell, Alicia M. Wells-Berlin, Ronald E. Therrien, Sally E. Yannuzzi, Catherine E. Carr Jan 2016

In-Air Hearing Of A Diving Duck: A Comparison Of Psychoacoustic And Auditory Brainstem Response Thresholds, Sara E. Crowell, Alicia M. Wells-Berlin, Ronald E. Therrien, Sally E. Yannuzzi, Catherine E. Carr

United States Geological Survey: Staff Publications

Auditory sensitivity was measured in a species of diving duck that is not often kept in captivity, the lesser scaup. Behavioral (psychoacoustics) and electrophysiological [the auditory brainstem response (ABR)] methods were used to measure in-air auditory sensitivity, and the resulting audiograms were compared. Both approaches yielded audiograms with similar U-shapes and regions of greatest sensitivity (2000-3000 Hz). However, ABR thresholds were higher than psychoacoustic thresholds at all frequencies. This difference was least at the highest frequency tested using both methods (5700 Hz) and greatest at 1000 Hz, where the ABR threshold was 26.8 dB higher than the behavioral measure of …


Urban Sprawl As A Risk Factor In Motor Vehicle Crashes, Reid Ewing, Shima Hamidi, James B. Grace Jan 2016

Urban Sprawl As A Risk Factor In Motor Vehicle Crashes, Reid Ewing, Shima Hamidi, James B. Grace

United States Geological Survey: Staff Publications

A decade ago, compactness/sprawl indices were developed for metropolitan areas and counties which have been widely used in health and other research. In this study, we first update the original county index to 2010, then develop a refined index that accounts for more relevant factors, and finally seek to test the relationship between sprawl and traffic crash rates using structural equation modelling. Controlling for covariates, we find that sprawl is associated with significantly higher direct and indirect effects on fatal crash rates. The direct effect is likely due to the higher traffic speeds in sprawling areas, and the indirect effect …


Polaris: A 30-Meter Probabilistic Soil Series Map Of The Contiguous United States, Nathaniel W. Chaney, Eric F. Wood, Alexander B. Mcbratney, Jonathan W. Hempel, Travis W. Nauman, Colby W. Brungard, Nathan P. Odgers Jan 2016

Polaris: A 30-Meter Probabilistic Soil Series Map Of The Contiguous United States, Nathaniel W. Chaney, Eric F. Wood, Alexander B. Mcbratney, Jonathan W. Hempel, Travis W. Nauman, Colby W. Brungard, Nathan P. Odgers

United States Geological Survey: Staff Publications

A newcomplete map of soil series probabilities has been produced for the contiguous United States at a 30mspatial resolution. This innovative database, named POLARIS, is constructed using available high-resolution geospatial environmental data and a state-of-the-art machine learning algorithm (DSMART-HPC) to remap the Soil Survey Geographic (SSURGO) database. This 9 billion grid cell database is possible using available high performance computing resources. POLARIS provides a spatially continuous, internally consistent, quantitative prediction of soil series. It offers potential solutions to the primary weaknesses in SSURGO: 1) unmapped areas are gap-filled using survey data from the surrounding regions, 2) the artificial discontinuities at …


Paying The Pipers: Mitigating The Impact Of Anticoagulant Rodenticides On Predators And Scavengers, John E. Elliott, Barnett A. Rattner, Richard F. Shore, Nico W. Van Den Brink Jan 2016

Paying The Pipers: Mitigating The Impact Of Anticoagulant Rodenticides On Predators And Scavengers, John E. Elliott, Barnett A. Rattner, Richard F. Shore, Nico W. Van Den Brink

United States Geological Survey: Staff Publications

Anticoagulant rodenticides, mainly second-generation forms, or SGARs, dominate the global market for rodent control. Introduced in the 1970s to counter genetic resistance in rodent populations to first-generation compounds such as warfarin, SGARs are extremely toxic and highly effective killers. However, their tendency to persist and accumulate in the body has led to the widespread contamination of terrestrial predators and scavengers. Commercial chemicals that are classified by regulators as persistent, bio-accumulative, and toxic (PBT) chemicals and that are widely used with potential environmental release, such as dichloro-diphenyl-trichloroethane (DDT) or polychlorinated biphenyls (PCBs), have been removed from commerce. However, despite consistently failing …


Chesapeake Bay Fish–Osprey (Pandion Haliaetus) Food Chain: Evaluation Of Contaminant Exposure And Genetic Damage, Rebecca S. Lazarus, Barnett A. Rattner, Peter C. Mcgowan, Robert C. Hale, Natalie K. Karouna-Renier, Richard A. Erickson, Mary Ann Ottinger Jan 2016

Chesapeake Bay Fish–Osprey (Pandion Haliaetus) Food Chain: Evaluation Of Contaminant Exposure And Genetic Damage, Rebecca S. Lazarus, Barnett A. Rattner, Peter C. Mcgowan, Robert C. Hale, Natalie K. Karouna-Renier, Richard A. Erickson, Mary Ann Ottinger

United States Geological Survey: Staff Publications

From 2011 to 2013, a large-scale ecotoxicological study was conducted in several Chesapeake Bay (USA) tributaries (Susquehanna River and flats, the Back, Baltimore Harbor/Patapsco Rivers, Anacostia/ middle Potomac, Elizabeth and James Rivers) and Poplar Island as a mid-Bay reference site. Osprey (Pandion haliaetus) diet and the transfer of contaminants from fish to osprey eggs were evaluated. The most bioaccumulative compounds (biomagnification factor>5) included p,p’-dichlorodiphenyldichloroethylene (DDE), total polychlorinated biphenyls (PCBs), total polybrominated diphenyl ethers (PBDEs), and bromodiphenyl ether (BDE) congeners 47, 99, 100, and 154. This analysis suggested that alternative brominated flame retardants and other compounds (methoxytriclosan) are not appreciably …


Immunoglobulin Detection Inwild Birds: Effectiveness Of Three Secondary Anti-Avian Igy Antibodies In Direct Elisas In 41 Avian Species, Carol A. Fassbinder-Orth, Travis E. Wilcoxen, Tiffany Tran, Raoul K. Boughton, Jeanne M. Fair, Erik K. Hofmeister, Jennifer L. Grindstaff, Jen C. Owen Jan 2016

Immunoglobulin Detection Inwild Birds: Effectiveness Of Three Secondary Anti-Avian Igy Antibodies In Direct Elisas In 41 Avian Species, Carol A. Fassbinder-Orth, Travis E. Wilcoxen, Tiffany Tran, Raoul K. Boughton, Jeanne M. Fair, Erik K. Hofmeister, Jennifer L. Grindstaff, Jen C. Owen

United States Geological Survey: Staff Publications

1.Immunological reagents for wild, non-model species are limited or often non-existent for many species.

2. In this study, we compare the reactivity of a newanti-passerine IgY secondary antibody with existing secondary antibodies developed for use with birds. Samples from 41 species from the following six avian orders were analysed: Anseriformes (1 family, 1 species), Columbiformes (1 family, 2 species), Galliformes (1 family, 1 species), Passeriformes (16 families, 34 species), Piciformes (1 family, 2 species) and Suliformes (1 family, 1 species). Direct ELISAs were performed to detect total IgY using goat anti-passerine IgY, goat anti-chicken IgY or goat anti-bird IgY secondary …


Elevation Dynamics In A Restored Versus A Submerging Salt Marsh In Long Island Sound, Shimon C. Anisfeld, Troy D. Hill, Daonald R. Cahoon Jan 2016

Elevation Dynamics In A Restored Versus A Submerging Salt Marsh In Long Island Sound, Shimon C. Anisfeld, Troy D. Hill, Daonald R. Cahoon

United States Geological Survey: Staff Publications

Accelerated sea-level rise (SLR) poses the threat of salt marsh submergence, especially in marshes that are relatively low-lying. At the same time, restoration efforts are producing new low-lying marshes, many of which are thriving and avoiding submergence. To understand the causes of these different fates, we studied two Long Island Sound marshes: one that is experiencing submergence and mudflat expansion, and one that is undergoing successful restoration. We examined sedimentation using a variety of methods, each of which captures different time periods and different aspects of marsh elevation change: surface-elevation tables, marker horizons, sediment cores, and sediment traps. We also …


Endangered Species Research In The Caribbean, James W. Wiley Jan 2016

Endangered Species Research In The Caribbean, James W. Wiley

United States Geological Survey: Staff Publications

Although indigenous Amerindian populations adversely affected the biota of their island environments, it was not until the arrival of Europeans that populations of many plant and animal species in the Caribbean Islands declined dramatically (Snyder and others, 1987). Island species are particularly vulnerable to changes in the environment, which, in the extreme, can lead to their extinction. The small populations of many species that occupy islands have limited gene pools and typically show extremes of specialization, characteristics that place those species at high risk for decline and extinction with rapid environmental change. The most important factor in the decline of …


The Bird Banding Laboratory: Support For And Collaboration With Research At Patuxent, John Tautin Jan 2016

The Bird Banding Laboratory: Support For And Collaboration With Research At Patuxent, John Tautin

United States Geological Survey: Staff Publications

Located at Patuxent Research Refuge (PRR) and functionally part of the Patuxent Wildlife Research Center (Patuxent), Laurel, MD, the Bird Banding Laboratory (BBL) is the service and administrative center for bird banding in the United States. Over the years, the BBL has been associated with both the PRR and Patuxent, which collectively are commonly referred to by the public (and in this chapter) as “Patuxent.” The BBL issues permits and bands; supplies banding software, instructional materials, and technical advice; coordinates the use of auxiliary markers such as neck collars and radio transmitters; serves as the repository for banding records and …


Endangered Species Research In Hawaii: The Early Years (1965–87), Michael J. Scott, Cameron B. Kepler Jan 2016

Endangered Species Research In Hawaii: The Early Years (1965–87), Michael J. Scott, Cameron B. Kepler

United States Geological Survey: Staff Publications

Hawaii is an ecologically isolated archipelago 2,500 miles from the nearest continent. Its isolation resulted in a taxonomically unbalanced flora and fauna with remarkable examples of adaptive radiation among those groups of organisms that won the dispersal sweepstakes. It was one of the last oceanic island groups to be populated by humans, about 900 A.D. by Polynesian travelers and in 1778 by Europeans. Relatively recent colonization by humans did not save it, however, from the biodiversity losses suffered by other isolated archipelagos—it only delayed them (Scott and others, 1988; Pratt and others, 2009a).


Seasonal Variation In The Ndvi–Species Richness Relationship In A Prairie Grassland Experiment (Cedar Creek), Ran Wang, John A. Gamon, Rebecca A. Montgomery, Philip A. Townsend, Arthur I. Zygielbaum, Keren Bitan, David Tilman, Jeannine Cavender-Bares Jan 2016

Seasonal Variation In The Ndvi–Species Richness Relationship In A Prairie Grassland Experiment (Cedar Creek), Ran Wang, John A. Gamon, Rebecca A. Montgomery, Philip A. Townsend, Arthur I. Zygielbaum, Keren Bitan, David Tilman, Jeannine Cavender-Bares

School of Natural Resources: Faculty Publications

Species richness generally promotes ecosystem productivity, although the shape of the relationship varies and remains the subject of debate. One reason for this uncertainty lies in the multitude of methodological approaches to sampling biodiversity and productivity, some of which can be subjective. Remote sensing offers new, objective ways of assessing productivity and biodiversity. In this study, we tested the species richness–productivity relationship using a common remote sensing index, the Normalized Difference Vegetation Index (NDVI), as a measure of productivity in experimental prairie grassland plots (Cedar Creek). Our study spanned a growing season (May to October, 2014) to evaluate dynamic changes …


The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center: January 2016, Martha Shulski, Natalie Umphlett, Crystal J. Stiles Jan 2016

The Prairie Post Quarterly Newsletter Of The High Plains Regional Climate Center: January 2016, Martha Shulski, Natalie Umphlett, Crystal J. Stiles

Prairie Post: Quarterly Newsletter of the High Plains Regional Climate Center

Inside this issue:

Message from the director........................................1

Staff spotlight...........................1

HPRCC staff changes..............2

Product highlight....................2

Research highlight..................2

Partnership spotlight.............3

AWDN information.................4

Update on regional climate conditions..................................4

Outreach/engagement.........5

Recent and upcoming travel and activities.............................6


Modeling The Effects Of Tile Drain Placement On The Hydrologic Function Of Farmed Prairie Wetlands1, Brett Werner, John Tracy, W. Carter Johnson, Richard A. Voldseth, Glenn R. Guntenspergen, Bruce Millett Jan 2016

Modeling The Effects Of Tile Drain Placement On The Hydrologic Function Of Farmed Prairie Wetlands1, Brett Werner, John Tracy, W. Carter Johnson, Richard A. Voldseth, Glenn R. Guntenspergen, Bruce Millett

United States Geological Survey: Staff Publications

The early 2000s saw large increases in agricultural tile drainage in the eastern Dakotas of North America. Agricultural practices that drain wetlands directly are sometimes limited by wetland protection pro- grams. Little is known about the impacts of tile drainage beyond the delineated boundaries of wetlands in upland catchments that may be in agricultural production. A series of experiments were conducted using the well-published model WETLANDSCAPE that revealed the potential for wetlands to have significantly shortened surface water inundation periods and lower mean depths when tile is placed in certain locations beyond the wet- land boundary. Under the soil conditions …


Late Holocene Expansion Of Ponderosa Pine (Pinus Ponderosa) In The Central Rocky Mountains, Usa, Jodi R. Norris, Julio L. Betancourt, Stephen T. Jackson Jan 2016

Late Holocene Expansion Of Ponderosa Pine (Pinus Ponderosa) In The Central Rocky Mountains, Usa, Jodi R. Norris, Julio L. Betancourt, Stephen T. Jackson

United States National Park Service: Publications

Aim: Ponderosa pine (Pinus ponderosa) experienced one of the most extensive and rapid post-glacial plant migrations in western North America. We used plant macrofossils from woodrat (Neotoma) middens to reconstruct its spread in the Central Rocky Mountains, identify other vegetation changes coinciding with P. ponderosa expansion at the same sites, and relate P. ponderosa migrational history to both its modern phylogeography and to a parallel expansion by Utah juniper (Juniperus osteosperma).

Location: Central Rocky Mountains, Wyoming and Montana, and Black Hills, Wyoming and South Dakota, USA.

Methods: Plant macrofossils were analysed in …


Adaptation On A Budget: How Vietnamese Innovators Are Trying To Design Their Way Out Of Climate Change, Shanti R. Johnson Jan 2016

Adaptation On A Budget: How Vietnamese Innovators Are Trying To Design Their Way Out Of Climate Change, Shanti R. Johnson

Graduate Student Theses, Dissertations, & Professional Papers

In the rapidly developing Mekong Delta of Vietnam, young innovators are facing a challenge far greater than simply trying to catch up with the wealthier world. In a growing trend, the next generation of Vietnamese is acting under a common understanding: climate change is real, it’s here and the time to respond is growing short.

For over a decade, Southern Vietnam has consistently been ranked by international organizations like the Intergovernmental Panel on Climate Change as one of the most vulnerable places in the world to the impacts of climate change. That vulnerability is heightened by the fact that the …


Missing The Trees For The Forest: The Socioecological Significance Of Dispersed Farmland Trees In Northern Ethiopia, Jacob A. Wall Jan 2016

Missing The Trees For The Forest: The Socioecological Significance Of Dispersed Farmland Trees In Northern Ethiopia, Jacob A. Wall

Honors Theses

Scattered trees are prominent features in the agricultural landscape of the Ethiopian highlands. The dry Afromontane forests of the Amhara Region in northern Ethiopia have faced centuries of deforestation - the FAO estimates only 3% of the region is forested today. The remaining landscape has been largely converted into agricultural and grazing lands, with the exception of some limited government-protected lands, as well as thousands of small forest fragments left around Orthodox Churches (“church forests”). But while a growing body of scholarship has highlighted the ecological and cultural importance of church forests and other natural forest fragments, the roles of …


A Comparison Between 2010 And 2006 Air Quality And Meteorological Conditions, And Emissions And Boundary Conditions Used In Simulations Of The Aqmeii-2 North American Domain, Till E. Stoeckenius, Christian Hogrefe, Justin Zagunis, Timonthy M. Sturtz, Benjamin Wells, Tanarit Sakulyanontvittaya Jan 2016

A Comparison Between 2010 And 2006 Air Quality And Meteorological Conditions, And Emissions And Boundary Conditions Used In Simulations Of The Aqmeii-2 North American Domain, Till E. Stoeckenius, Christian Hogrefe, Justin Zagunis, Timonthy M. Sturtz, Benjamin Wells, Tanarit Sakulyanontvittaya

United States Environmental Protection Agency: Publications

Several participants in Phase 2 of the Air Quality Model Evaluation International Initiative (AQMEII-2) who are applying coupled models to the North American domain are comparing model results for two years, 2006 and 2010, with the goal of performing dynamic model evaluation. From a modeling perspective, the differences of interest are the large reductions in domain total emissions of NOx (21%) and SO2 (37%) from 2006 to 2010 and significant differences in meteorological conditions between these two years. The emission reductions occurred mostly in the eastern U.S, with some reduction in emissions from western wildfires in 2010. Differences …


Potential Aquifer Vulnerability In Regions Down-Gradient From Uranium In Situ Recovery (Isr) Sites, James A. Saunders, Bruce E. Pivetz, Nathan Voorhies, Richard T. Wilkin Jan 2016

Potential Aquifer Vulnerability In Regions Down-Gradient From Uranium In Situ Recovery (Isr) Sites, James A. Saunders, Bruce E. Pivetz, Nathan Voorhies, Richard T. Wilkin

United States Environmental Protection Agency: Publications

Sandstone-hosted roll-front uranium ore deposits originate when U(VI) dissolved in groundwater is reduced and precipitated as insoluble U(IV) minerals. Groundwater redox geochemistry, aqueous complexation, and solute migration are important in leaching uranium from source rocks and transporting it in low concentrations to a chemical redox interface where it is deposited in an ore zone typically containing the uranium minerals uraninite, pitchblende, and/or coffinite; various iron sulfides; native selenium; clays; and calcite. In situ recovery (ISR) of uranium ores is a process of contacting the uranium mineral deposit with leaching and oxidizing (lixiviant) fluids via injection of the lixiviant into wells …


Identification Of Putative Geographically Isolated Wetlands Of The Conterminous United States, Charles R. Lane, Ellen D'Amico Jan 2016

Identification Of Putative Geographically Isolated Wetlands Of The Conterminous United States, Charles R. Lane, Ellen D'Amico

United States Environmental Protection Agency: Publications

Geographically isolated wetlands (GIWs) are wetlands completely surrounded by uplands. While common throughout the United States (U.S.), there have heretofore been no nationally available, spatially explicit estimates of GIW extent, complicating efforts to understand the myriad biogeochemical, hydrological, and habitat functions of GIWs and hampering conservation and management efforts at local, state, and national scales. We used a 10-m geospatial buffer as a proxy for hydrological or ecological connectivity of National Wetlands Inventory palustrine and lacustrine wetland systems to nationally mapped and available stream, river, and lake data. We identified over 8.3 million putative GIWs across the conterminous U.S., encompassing …


Water Consumption Estimates Of The Biodiesel Process In The Us, Qingshi Tu, Mingming Lu, Y. Jeffrey Yang, Don Scott Jan 2016

Water Consumption Estimates Of The Biodiesel Process In The Us, Qingshi Tu, Mingming Lu, Y. Jeffrey Yang, Don Scott

United States Environmental Protection Agency: Publications

As a renewable alternative to petroleum diesel, biodiesel has been widely used in the US and the world. However, its potential impact on water resources has not been much evaluated. This study investigates water consumption from the biodiesel process, which includes three stages: soybean irrigation, soybean-to-soybean oil processing, and biodiesel manufacturing, at both national and state levels. Mass-based allocation is performed and water consumption at the three stages is obtained on the basis of million gallons per year and gallon water per gallon biodiesel (gal/gal). The normalized water consumption (water intensity) of the irrigation, oil processing, and biodiesel production stages …


Quantitative Structure–Mesothelioma Potency Model Optimization For Complex Mixtures Of Elongated Particles In Rat Pleura: A Retrospective Study, Philip M. Cook, Joseph Swintek, Timothy D. Dawson, David Chapman, Mathew A. Etterson, Dale Hoff Jan 2016

Quantitative Structure–Mesothelioma Potency Model Optimization For Complex Mixtures Of Elongated Particles In Rat Pleura: A Retrospective Study, Philip M. Cook, Joseph Swintek, Timothy D. Dawson, David Chapman, Mathew A. Etterson, Dale Hoff

United States Environmental Protection Agency: Publications

Cancer potencies of mineral and synthetic elongated particle mixtures, including asbestos fibers, are influenced by changes in fiber dose composition, bioavailability, and biodurability in combination with relevant cytotoxic dose-response relationships. An extensive rat intrapleural dose characterization data set with a wide variety of elongated particles physicochemical properties facilitated statistical analyses of pleural mesothelioma response data combined from several studies for evaluation of alternative dose-response models. Utilizing logistic regression of individual elongated particle dimensional variations within each test sample, four major findings emerged: (1) Mild acid leaching provides superior prediction of tumor incidence compared to samples that were not leached; (2) …


Quantitative Structure–Mesothelioma Potency Model Optimization For Complex Mixtures Of Elongated Particles In Rat Pleura: A Retrospective Study, Philip M. Cook, Joseph Swintek, Timothy D. Dawson, David Chapman, Mathew A. Etterson, Dale Hoff Jan 2016

Quantitative Structure–Mesothelioma Potency Model Optimization For Complex Mixtures Of Elongated Particles In Rat Pleura: A Retrospective Study, Philip M. Cook, Joseph Swintek, Timothy D. Dawson, David Chapman, Mathew A. Etterson, Dale Hoff

United States Environmental Protection Agency: Publications

Cancer potencies of mineral and synthetic elongated particle mixtures, including asbestos fibers, are influenced by changes in fiber dose composition, bioavailability, and biodurability in combination with relevant cytotoxic dose-response relationships. An extensive rat intrapleural dose characterization data set with a wide variety of elongated particles physicochemical properties facilitated statistical analyses of pleural mesothelioma response data combined from several studies for evaluation of alternative dose-response models. Utilizing logistic regression of individual elongated particle dimensional variations within each test sample, four major findings emerged: (1) Mild acid leaching provides superior prediction of tumor incidence compared to samples that were not leached; (2) …


Gross And Microscopic Lesions In Corals From Micronesia, T. M. Work, G. S. Aeby, K. A. Hughen Jan 2016

Gross And Microscopic Lesions In Corals From Micronesia, T. M. Work, G. S. Aeby, K. A. Hughen

United States Geological Survey: Staff Publications

The authors documented gross and microscopic morphology of lesions in corals on 7 islands spanning western, southern, and eastern Micronesia, sampling 76 colonies comprising 30 species of corals among 18 genera, with Acropora, Porites, and Montipora dominating. Tissue loss comprised the majority of gross lesions sampled (41%), followed by discoloration (30%) and growth anomaly (29%). Of 31 cases of tissue loss, most lesions were subacute (48%), followed by acute and chronic (26% each). Of 23 samples with discoloration, most were dark discoloration (40%), with bleaching and other discoloration each constituting 30%. Of 22 growth anomalies, umbonate growth anomalies composed …