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2017

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Articles 391 - 420 of 437

Full-Text Articles in Geology

Detection Of Sedimentary Depositional Cycles In The Salado Formation, Southeastern New Mexico, Scott Paul Milo Jan 2017

Detection Of Sedimentary Depositional Cycles In The Salado Formation, Southeastern New Mexico, Scott Paul Milo

Electronic Theses and Dissertations

An abundance of evaporitic features is preserved throughout the approximately 2,000-foot-thick Salado formation that is present across west Texas and southeastern New Mexico. The formation and preservation of evaporitic features are largely influenced by hydrology, and so those found in the Salado represent an uninterrupted record of hydrogeologic conditions in what is now the southwestern United States during the late Permian. Because it is home to the Waste Isolation Pilot Plant (WIPP) repository chamber, the salado has been the subject of countless studies ranging from areas of sedimentology, to geochemistry, to geotechnical engineering, to hydrology. However, until now there have …


Constraining Times Of Extension In The Southern Rio Grande Rift And Basin And Range Using Apatite And Zircon (U-Th)/He Thermochronology, Julian Biddle Jan 2017

Constraining Times Of Extension In The Southern Rio Grande Rift And Basin And Range Using Apatite And Zircon (U-Th)/He Thermochronology, Julian Biddle

Open Access Theses & Dissertations

The Rio Grande rift and the Basin and Range are adjacent extensional domains that have evolved contemporaneously in western North America. Although the rift is often considered to be the easternmost boundary of Basin and Range extension, there is geologic and geophysical evidence that suggests the two are discrete provinces. Existing low-temperature thermochronologic data indicate that a period of synchronous extension occurred across the entire length of the rift from ~25-10 Ma. However, these studies were more focused on the northern and central sections of the rift, and thermochronologic data remains sparse in southern New Mexico. We collected rock samples …


Cycling Of Gypsiferous White Sands Aerosols In The Shallow Critical Zone At White Mountain, New Mexico, Patrick Richard Rea Jan 2017

Cycling Of Gypsiferous White Sands Aerosols In The Shallow Critical Zone At White Mountain, New Mexico, Patrick Richard Rea

Open Access Theses & Dissertations

Dry deposition significantly affects evolution of the critical zone by nutrient supply and contributing to soil genesis. Dust influx and cycling in soils are difficult to quantify because dust sources can be chemically similar to local soils. White Sands, New Mexico, emits gypsum dust with a unique chemical and isotopic signature, providing an opportunity to investigate dust deposition and its movement in soils. This study evaluated the mobility of White Sands dust particles in the critical zone at White Mountain, New Mexico, a highland 100 km downwind. Four soil profiles were collected over limestone, igneous, mixed limestone and dolostone, and …


Genesis Of Unique Carbonate Fans In A Pre-Salt Reservoir Analogue, Indio Mountains, West Texas, Andre Llanos Jan 2017

Genesis Of Unique Carbonate Fans In A Pre-Salt Reservoir Analogue, Indio Mountains, West Texas, Andre Llanos

Open Access Theses & Dissertations

Hydrocarbon exploration in pre-salt sediments of rift basins on the South Atlantic Margin have proven to be successful major oil plays. Located on the western margin of the rift, the Brazilian pre-salt reservoirs of the Santos, Campos, and Espirito Santo Basins are hosted by lacustrine/marine-influenced carbonates that comprise laterally extensive, laminated microbialite facies. The Indio Mountains, located in West Texas, provide well-exposed outcrops of Lower Cretaceous marine and non-marine rift basin strata that can be considered a reservoir-analog to the South Atlantic Margin pre-salt facies. Of particular interest for hydrocarbon exploration are unique carbonate features that have been discovered in …


A Quantitative Analysis Of The Fretted Terrain Valleys, Arabia Terra, Mars, Kelsey Anne Mason Jan 2017

A Quantitative Analysis Of The Fretted Terrain Valleys, Arabia Terra, Mars, Kelsey Anne Mason

Open Access Theses & Dissertations

Fretted terrain describes regions on Mars with low-lying, flat valleys separated by steep cliffs that often form polygonal-shaped mesas. The fretted terrain valleys have a morphology distinct from other valleys found on Mars, and their unknown origin may hold insights into critical questions about Mars' tectonic, magmatic, and hydrologic history. Current hypoThesis for the formation of the fretted terrain include fracturing as well as hydrological flow processes such as fluvial or glacial erosion. The region for this study is located in eastern Arabia Terra and is the type-location for fretted terrain. By qualitatively and quantitatively documenting the planform, or map-view, …


Depositional Controls And Sequence Stratigraphy Of Lacustrine To Marine Transgressive Deposits In A Rift Basin, Lower Cretaceous Bluff Mesa, Indio Mountains, West Texas, Andrew Anderson Jan 2017

Depositional Controls And Sequence Stratigraphy Of Lacustrine To Marine Transgressive Deposits In A Rift Basin, Lower Cretaceous Bluff Mesa, Indio Mountains, West Texas, Andrew Anderson

Open Access Theses & Dissertations

Successful hydrocarbon exploration in former rift basins of the South Atlantic pre-salt has generated interest in understanding depositional, diagenetic, and stratigraphic controls on pre-salt deposits. However, most studies to date have focused on attributes and controls on presalt lacustrine carbonate reservoir systems and little work has been done on the overlying marine sealing facies. Currently our standard sequence stratigraphic model of marine transgression of rift systems involves a single pulse of marine flooding over fluvially-incised valleys resulting in backstepping of fluvial and estuarine siliciclastic facies within the erosionally confined zone of an incised valley. However, the pre-salt systems of the …


Preservation Of Sea Anemone Burrows In Silurian (~432 Million Years Old) Carbonate Rocks Of Southeastern Indiana, Usa, Marissa Tomin Jan 2017

Preservation Of Sea Anemone Burrows In Silurian (~432 Million Years Old) Carbonate Rocks Of Southeastern Indiana, Usa, Marissa Tomin

Williams Honors College, Honors Research Projects

Preservation of trace fossils (ichnofossils) in siliciclastic environments is often quite different from preservation in carbonate environments, representing an important source of variation that must be well understood in order to enhance interpretations of paleoenvironments and paleoecology. This study focuses on Conostichus, a relatively common burrow constructed by solitary sea anemones. These trace fossils are generally well-preserved (i.e., they display detailed external features) in siliciclastic rocks but are typically little more than conical masses in carbonate rocks. However, certain specimens recovered from the middle Silurian Massie Formation at the Napoleon quarry of southeastern Indiana are composed entirely out of …


Archived Rock Samples From Jane Selverstone's Research Collection, Jane Selverstone Jan 2017

Archived Rock Samples From Jane Selverstone's Research Collection, Jane Selverstone

Earth and Planetary Sciences Faculty and Staff Publications

This Excel spreadsheet lists all of the rock samples from Jane Selverstone's research collection that have been archived into the Earth and Planetary Sciences Collections at the University of New Mexico. All samples are listed by original (published) sample number and by an affiliated International GeoSample Number. Samples are grouped by research project, and doi information is given for all publications resulting from work on each project. Rock samples include various combinations of hand specimens, powders, thin sections, and billets from which thin sections were prepared. Information is included to identify the drawers within which each sample can be found …


A Spatial Analysis Of Climate Change Effects On Maize Productivity In Kenya, Dan Wanyama Jan 2017

A Spatial Analysis Of Climate Change Effects On Maize Productivity In Kenya, Dan Wanyama

Theses

Climate change has intensified the risk of catastrophic natural disasters all over the world. Though impacts of the change are global, developing countries are more at risk. Although agriculture remains the backbone of Kenya’s economy, the sector’s dependence on natural resources increases its vulnerability to the aggravating impacts of climate change and variability. Climate system variations that impact staple food crops like maize (Zea mays) ultimately threaten the food security of the nation. This study examined environmental factors affecting maize productivity through regression analysis. A GIS suitability model for maize was also developed to identify Kenya’s different levels of suitability …


Underground Structures, Rock Structures And Rock Mechanics From Ancient Era To The Modern Age, Ebru Akiş, Özgür Satici Jan 2017

Underground Structures, Rock Structures And Rock Mechanics From Ancient Era To The Modern Age, Ebru Akiş, Özgür Satici

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Usage of underground space is an old habit for human beings since ancient era. Our ancestors have used caves as a shelter for protection from the wildlife and nature, and they excavated caves to extract valuable minerals. They also used them as sanctuaries, tombs or for storage of goods. In addition, they built tunnels to be used as assault systems or to underpass fortifications during ancient warfare. Later on, tunnels were driven to supply water to the towns or to protect the towns from floods. They also built them for communication purposes. Though not knowing the exact time when they …


Assessment Of Vadose-Zone Wells For Enhancing Groundwater Recharge In The Mississippi Delta, Luke Jenkins Jan 2017

Assessment Of Vadose-Zone Wells For Enhancing Groundwater Recharge In The Mississippi Delta, Luke Jenkins

Honors Theses

Current pumping rates in the Mississippi River Valley Alluvial Aquifer in the Mississippi Delta are unsustainable as they are depleting the water level in the aquifer. The following thesis is a feasibility analysis on groundwater recharge to the Mississippi River Valley Alluvial Aquifer using vadose zone wells. Two days were spent in the field at Sky Lake near Belzoni, Mississippi, collecting core soil samples, bag soil samples, and constant head hydraulic conductivity values. Numerous days were spent in the lab conducting sieve analyses, Atterberg limits, and falling head hydraulic conductivity tests. The Atterberg limit test and sieve analyses were used …


Imaging Bioturbation In Supratidal Carbonates: Non-Invasive Field Techniques Enhance Neoichnological And Zoogeomorphological Research, San Salvador, The Bahamas, Karen Kopcznski, Ilya Buynevich, H. Allen Curran, Jon Caris, Jonathan Nyquist Jan 2017

Imaging Bioturbation In Supratidal Carbonates: Non-Invasive Field Techniques Enhance Neoichnological And Zoogeomorphological Research, San Salvador, The Bahamas, Karen Kopcznski, Ilya Buynevich, H. Allen Curran, Jon Caris, Jonathan Nyquist

Geosciences: Faculty Publications

A case study in unconsolidated carbonates on San Salvador Island, The Bahamas, utilized high-frequency (800 MHz) georadar imaging to augment existing methodologies (burrow counts and measurements, casting) in brachyuran bioturbation research (Ocypode quadrata and Gecarcinus lateralis), and as part of a new dataset characterizing blue land crab (Cardisoma guanhumi) burrows. Non-invasive techniques such as ground-penetrating radar (GPR) can complement traditional field surveys aimed at quantifying mesoscale bioturbation in modern settings. These methods can establish diagnostic features for tracemaker identification and refine existing ichnofacies models. Drone-mounted aerial coverage provided the first high-resolution images of the micro-topography and …


Post-Rift Magmatic Evolution Of The Eastern North American “Passive-Aggressive” Margin, Sarah E. Mazza, Esteban Gazel, Elizabeth A. Johnson, Michael Bizimis, Ryan Mcaleer, C. Berk Biryol Jan 2017

Post-Rift Magmatic Evolution Of The Eastern North American “Passive-Aggressive” Margin, Sarah E. Mazza, Esteban Gazel, Elizabeth A. Johnson, Michael Bizimis, Ryan Mcaleer, C. Berk Biryol

Geosciences: Faculty Publications

Understanding the evolution of passive margins requires knowledge of temporal and chemical constraints on magmatism following the transition from supercontinent to rifting, to post-rifting evolution. The Eastern North American Margin (ENAM) is an ideal study location as several magmatic pulses occurred in the 200 My following rifting. In particular, the Virginia-West Virginia region of the ENAM has experienced two postrift magmatic pulses at ∼152 Ma and 47 Ma, and thus provides a unique opportunity to study the long-term magmatic evolution of passive margins. Here we present a comprehensive set of geochemical data that includes new Ar/ Ar ages, major and …


Using Lidar To Map The Geology And Morphology Of Alluvial Fans: Salton Sea Area, California, Eric Alexander Macleod Jan 2017

Using Lidar To Map The Geology And Morphology Of Alluvial Fans: Salton Sea Area, California, Eric Alexander Macleod

Dissertations, Master's Theses and Master's Reports

The main result of this study has been to show that detailed maps of the geology and morphology of alluvial fans can be generated from high spatial resolution (1-meter) DEM’s (Digital Elevation Models) obtained from LiDAR (Light Detection and Ranging) data. DEMs with spatial resolutions of 1-meter, 10-meters and 30-meters were all examined but it was determined that only the 1-meter LiDAR data had sufficient spatial resolution to produce satisfactory maps of the geology and morphology. A case study on an alluvial fan in the Santa Rosa mountains northeast of the Salton Sea (California) showed that 1-meter spatial resolution LiDAR …


Developing A Gis Tool For Infinite Slope Stability Analysis (Gis-Tissa), Jonathon Sanders Jan 2017

Developing A Gis Tool For Infinite Slope Stability Analysis (Gis-Tissa), Jonathon Sanders

Dissertations, Master's Theses and Master's Reports

The Probabilistic Infinite Slope Analysis model (PISA-m) is a widely used computer program that uses infinite slope equations to calculate the spatially varying Factor of Safety of slopes. ESRI’s ArcGIS software and accompanying geoprocessing tools have become a mainstay in spatial data processing, and received full support for Python with the release of version 10. With many of the geoprocessing tools now available as a Python function, the software can be used for physics-based spatial landslide hazard analysis. A model that mimics PISA-m and its processing of normally distributed soil properties was created using the Python utility as a tool …


Rock Magnetic Investigation Of The Michigan Basin Soils And Sediments Overlying The Oil-Bearing Silurian Pinnacle Reefs, Jake Tresnak Jan 2017

Rock Magnetic Investigation Of The Michigan Basin Soils And Sediments Overlying The Oil-Bearing Silurian Pinnacle Reefs, Jake Tresnak

Dissertations, Master's Theses and Master's Reports

A relationship between the hydrocarbon migration and magnetic properties of near-surface sediments was investigated from several hundreds of samples collected over the hydrocarbon-bearing Silurian pinnacle reef belt of the Michigan Basin. The collected samples were investigated using several rock magnetic methods and optical microscopy. The investigation has not revealed a straightforward relationship between the magnetic susceptibility and hydrocarbon reservoirs within the reef belt; both anomalously high and low susceptibility values were observed. The elevated values are associated with newly formed magnetite in the form of spheroidal grains produced by hydrocarbon-related diagenesis while the extremely low susceptibilities may reflect dissolution of …


Exploring The Reasons For The Seasons Using Google Earth, 3d Models, And Plots, Declan G. De Paor, Mladen M. Dordevic, Paul Karabinos, Stephen Burgin, Filis Coba, Steven J. Whitmeyer Jan 2017

Exploring The Reasons For The Seasons Using Google Earth, 3d Models, And Plots, Declan G. De Paor, Mladen M. Dordevic, Paul Karabinos, Stephen Burgin, Filis Coba, Steven J. Whitmeyer

Physics Faculty Publications

Public understanding of climate and climate change is of broad societal importance. However, misconceptions regarding reasons for the seasons abound amongst students, teachers, and the public, many of whom believe that seasonality is caused by large variations in Earth's distance from the Sun. Misconceptions may be reinforced by textbook illustrations that exaggerate eccentricity or show an inclined view of Earth's near-circular orbit. Textbook explanations that omit multiple factors influencing seasons, that do not mesh with students' experiences, or that are erroneous, hinder scientifically valid reasoning. Studies show that many teachers share their students' misconceptions, and even when they understand basic …


Glacial To Holocene Changes In Eastern Equatorial Pacific Deep-Water Chemistry And Circulation, Natalie E. Umling Jan 2017

Glacial To Holocene Changes In Eastern Equatorial Pacific Deep-Water Chemistry And Circulation, Natalie E. Umling

Theses and Dissertations

It has been hypothesized that the oceans store CO2 during glacial periods and then release it to the atmosphere, causing the onset of warm interglacial periods (Sigman and Boyle, 2000). Documenting this past transfer of CO2 between the oceans and atmosphere is of utmost importance for better understanding the impact that anthropogenic CO2 has and will have on Earth’s climate. The last deglaciation is a good analogue to modern increases in CO2 and temperature and is recent enough to be studied using radiocarbon. This period provides important insights into the nature of climate changes during the transition from glacial to …


Review Of A Chorus Of Cranes: The Cranes Of North America And The World By Paul A. Johnsgard, Aaron T. Pearse Jan 2017

Review Of A Chorus Of Cranes: The Cranes Of North America And The World By Paul A. Johnsgard, Aaron T. Pearse

United States Geological Survey: Staff Publications

Cranes (Gruidae) are widely distributed throughout the world, have lived on Earth for several million years, and currently reside on five continents. Archaeological evidence and historical references suggest that humans have interacted with and been captivated by cranes for many thousands of years (e.g., Leslie 1988, Muellner 1990). A glimpse of our reverence for these birds can be found in A Chorus of Cranes by Paul A. Johnsgard, with photographs by Thomas D. Mangelsen. Many species of cranes are currently identified as threatened or endangered, and their future will likely rest in the hands of humans; this book presents their …


Variation In Δ15N And Δ13C Values Of Forages For Arctic Caribou: Effects Of Location, Phenology And Simulated Digestion, Lindsay L. Vansomeren, Perry S. Barboza, David D. Gustine, M. Syndonia Bret-Harte Jan 2017

Variation In Δ15N And Δ13C Values Of Forages For Arctic Caribou: Effects Of Location, Phenology And Simulated Digestion, Lindsay L. Vansomeren, Perry S. Barboza, David D. Gustine, M. Syndonia Bret-Harte

United States Geological Survey: Staff Publications

RATIONALE: The use of stable isotopes for dietary estimates of wildlife assumes that there are consistent differences in isotopic ratios among diet items, and that the differences in these ratios between the diet item and the animal tissues (i.e., fractionation) are predictable. However, variation in isotopic ratios and fractionation of δ13C and δ15N values among locations, seasons, and forages are poorly described for arctic herbivores especially migratory species such as caribou (Rangifer tarandus).

METHODS: We measured the δ13Cand δ15N values of seven species of forage growing along a 200-km …


Comparison Of Acoustic Recorders And Field Observers For Monitoring Tundra Bird Communities, Skyler T. Vold, Colleen M. Handel, Lance B. Mcnew Jan 2017

Comparison Of Acoustic Recorders And Field Observers For Monitoring Tundra Bird Communities, Skyler T. Vold, Colleen M. Handel, Lance B. Mcnew

United States Geological Survey: Staff Publications

Acoustic recorders can be useful for studying bird populations but their efficiency and accuracy should be assessed in pertinent ecological settings before use. We investigated the utility of an acoustic recorder formonitoring abundance of tundra-breeding birds relative to point-count surveys in northwestern Alaska, USA, during 2014. Our objectives were to 1) compare numbers of birds and species detected by a field observer with those detected simultaneously by an acoustic recorder; 2) evaluate how detection probabilities for the observer and acoustic recorder varied with distance of birds from the survey point; and 3) evaluate whether avian guild-specific detection rates differed between …


Assessment Of Frequency And Duration Of Point Counts When Surveying For Golden Eagle Presence, Ben R. Skipper, Clint W. Boal, Jo-Szu Tsai, Mark R. Fuller Jan 2017

Assessment Of Frequency And Duration Of Point Counts When Surveying For Golden Eagle Presence, Ben R. Skipper, Clint W. Boal, Jo-Szu Tsai, Mark R. Fuller

United States Geological Survey: Staff Publications

We assessed the utility of the recommended golden eagle (Aquila chrysaetos) survey methodology in the U.S. Fish and Wildlife Service 2013 Eagle Conservation Plan Guidance. We conducted 800-m radius, 1-hr point-count surveys broken into 20-min segments, during 2 sampling periods in 3 areas within the Intermountain West of the United States over 2 consecutive breeding seasons during 2012 and 2013. Our goal was to measure the influence of different survey time intervals and sampling periods on detectability and use estimates of golden eagles among different locations. Our results suggest that a less intensive effort (i.e., survey duration shorter …


Micronuclei And Other Erythrocyte Nuclear Abnormalities In Fishes From The Great Lakes Basin,Usa, Ryan P. Braham, Vicki S. Blazer, Cassidy H. Shaw, Patricia M. Mazik Jan 2017

Micronuclei And Other Erythrocyte Nuclear Abnormalities In Fishes From The Great Lakes Basin,Usa, Ryan P. Braham, Vicki S. Blazer, Cassidy H. Shaw, Patricia M. Mazik

United States Geological Survey: Staff Publications

Biological markers (biomarkers) sensitive to genotoxic and mutagenic contamination in fishes are widely used to identify exposure effects in aquatic environments. The micronucleus assay was incorporated into a suite of indicators to assess exposure to genotoxic and mutagenic contamination at five Great Lakes Areas of Concern (AOCs), as well as one non-AOC (reference) site. The assay allowed enumeration of micronuclei as well as other nuclear abnormalities for both site and species comparisons. Erythrocyte abnormality data was also compared to skin and liver tumor prevalence and hepatic transcript abundance. Erythrocyte abnormalities were observed at all sites with variable occurrence and severity …


Lack Of Observed Movement Response To Lead Exposure Of California Condors, Sharon A. Poessel, Joseph Brandt, Linda Uyeda, Molly Astell, Todd E. Katzner Jan 2017

Lack Of Observed Movement Response To Lead Exposure Of California Condors, Sharon A. Poessel, Joseph Brandt, Linda Uyeda, Molly Astell, Todd E. Katzner

United States Geological Survey: Staff Publications

Lead poisoning is an important conservation concern for wildlife, and scavenging birds are especially at risk from consumption of carcasses of animals killed with lead ammunition. Because current methods to identify lead exposure require animal capture and blood collection, management would benefit from the development of a less costly and noninvasive behavioral test for illness in wild animals. We attempted to design such a test to identify lead exposure in California condors (Gymnogyps californianus) that we tracked with global positioning system (GPS) telemetry in southern California, USA, 2013–2016. We measured blood-lead concentrations in tracked birds and expected that …


Challenges For Creating A Site-Specific Groundwater-Use Record For The Ozark Plateaus Aquifer System (Central Usa) From 1900 To 2010, Katherine J. Knierim, Anna M. Nottmeier, Scott Worland, Drew A. Westerman, Brian R. Clark Jan 2017

Challenges For Creating A Site-Specific Groundwater-Use Record For The Ozark Plateaus Aquifer System (Central Usa) From 1900 To 2010, Katherine J. Knierim, Anna M. Nottmeier, Scott Worland, Drew A. Westerman, Brian R. Clark

United States Geological Survey: Staff Publications

Hydrologic budgets to determine groundwater availability are important tools for water-resource managers. One challenging component for developing hydrologic budgets is quantifying water use through time because historical and site-specific water-use data can be sparse or poorly documented. This research developed a groundwater-use record for the Ozark Plateaus aquifer system (central USA) from 1900 to 2010 that related county-level aggregated water-use data to site-specific well locations and aquifer units. A simple population-based linear model, constrained to 0 million liters per day in 1900, provided the best means to extrapolate groundwater-withdrawal rates pre-1950s when there was a paucity of water-use data. To …


Temporal Shift Of Sea Turtle Nest Sites In An Eroding Barrier Island Beach, Ikuko Fujisaki, Margaret Lamont, Ray Carthy Jan 2017

Temporal Shift Of Sea Turtle Nest Sites In An Eroding Barrier Island Beach, Ikuko Fujisaki, Margaret Lamont, Ray Carthy

United States Geological Survey: Staff Publications

Shoreline changes affect functionality of a sandy beach as a wildlife habitat and coastal erosion is among the primary causes of the changes. We examined temporal shifts in locations where loggerheads placed nests in relation to coastal erosion along a barrier island beach in the northern Gulf of Mexico. We first confirmed consistency in long-term (1855–2001), short-term (1976–2001), and more recent (2002–2012) shoreline change rates in two adjacent beach sections, one historically eroding (west beach) and the other accreting (east beach). The mean annual shoreline change rate in the two sections was significantly different in all time periods. The recent …


Habitat Mosaics And Path Analysis Can Improve Biological Conservation Of Aquatic Biodiversity In Ecosystems With Low-Head Dams, Sean M. Hitchman, Martha E. Mather, Joseph M. Smith, Jane S. Fencl Jan 2017

Habitat Mosaics And Path Analysis Can Improve Biological Conservation Of Aquatic Biodiversity In Ecosystems With Low-Head Dams, Sean M. Hitchman, Martha E. Mather, Joseph M. Smith, Jane S. Fencl

United States Geological Survey: Staff Publications

Conserving native biodiversity depends on restoring functional habitats in the face of human-induced disturbances. Low-head dams are a ubiquitous human impact that degrades aquatic ecosystems worldwide. To improve our understanding of how low-head dams impact habitat and associated biodiversity, our research examined complex interactions among three spheres of the total environment. i.e., how low-head dams (anthroposphere) affect aquatic habitat (hydrosphere), and native biodiversity (biosphere) in streams and rivers. Creation of lake-like habitats upstream of low-head dams is a well-documented major impact of dams. Alterations downstream of low head dams also have important consequences, but …


Degradation Of Crude 4‑Mchm (4-Methylcyclohexanemethanol) In Sediments From Elk River, West Virginia, Isabelle M. Cozzarelli, Denise M. Akob, Mary Jo Baedecker, Tracey Spencer, Jeanne Jaeschke, Darren S. Dunlap, Adam C. Mumford, Amisha T, Poret-Peterson, Douglas B. Chambers Jan 2017

Degradation Of Crude 4‑Mchm (4-Methylcyclohexanemethanol) In Sediments From Elk River, West Virginia, Isabelle M. Cozzarelli, Denise M. Akob, Mary Jo Baedecker, Tracey Spencer, Jeanne Jaeschke, Darren S. Dunlap, Adam C. Mumford, Amisha T, Poret-Peterson, Douglas B. Chambers

United States Geological Survey: Staff Publications

In January 2014, approximately 37 800 L of crude 4-methylcyclohexanemethanol (crude MCHM) spilled into the Elk River, West Virginia. To understand the long-term fate of 4-MCHM, we conducted experiments under environmentally relevant conditions to assess the potential for the 2 primary compounds in crude MCHM (1) to undergo biodegradation and (2) for sediments to serve as a long-term source of 4-MCHM. We developed a solid phase microextraction (SPME) method to quantify the cis- and transisomers of 4-MCHM. Autoclaved Elk River sediment slurries sorbed 17.5% of cis-4-MCHM and 31% of trans-4-MCHM from water during the 2-week experiment. …


Floristic Quality Index And Forested Floristic Quality Index: Assessment Tools For Restoration Projects And Monitoring Sites In Coastal Louisiana, Kari F. Cretini, William B. Wood, Jenneke M. Visser, Ken W. Krauss, Leigh Anne Sharp, Gregory D. Steyer, Gary P. Shaffer, Sarai C. Piazza Jan 2017

Floristic Quality Index And Forested Floristic Quality Index: Assessment Tools For Restoration Projects And Monitoring Sites In Coastal Louisiana, Kari F. Cretini, William B. Wood, Jenneke M. Visser, Ken W. Krauss, Leigh Anne Sharp, Gregory D. Steyer, Gary P. Shaffer, Sarai C. Piazza

United States Geological Survey: Staff Publications

In 2003, the Coastwide Reference Monitoring System (CRMS) program was established in coastal Louisiana marshes and swamps to assess the effectiveness of individual coastal restoration projects and the cumulative effects of multiple projects at regional and coastwide scales (Steyer et al., 2003). In order to make these assessments, analytical teams were assembled for each of the primary data types sampled under theCRMS program, including vegetation, hydrology, landscape, and soils. These teams consisted of scientists and support staff from the US Geological Survey and other federal agencies, the Coastal Protection and Restoration Authority of Louisiana, and university academics. Each team was …


The Aerosphere As A Network Connector Of Organisms And Their Diseases, Jeremy D. Ross, Eli S. Bridge, Diann J. Prosser, John Y. Takekawa Jan 2017

The Aerosphere As A Network Connector Of Organisms And Their Diseases, Jeremy D. Ross, Eli S. Bridge, Diann J. Prosser, John Y. Takekawa

United States Geological Survey: Staff Publications

Aeroecological processes, especially powered flight of animals, can rapidly connect biological communities across the globe. This can have profound consequences for evolutionary diversification, energy and nutrient transfers, and the spread of infectious diseases. The latter is of particular consequence for human populations, since migratory birds are known to host diseases which have a history of transmission into domestic poultry or even jumping to human hosts. In this chapter, we present a scenario under which a highly pathogenic avian influenza (HPAI) strain enters North America from East Asia via postmolting waterfowl migration. We use an agent-based model (ABM) to simulate the …