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Articles 151 - 180 of 918

Full-Text Articles in Geology

Groundwater Availability Of The Northern High Plains Aquifer In Colorado, Kansas, Nebraska, South Dakota, And Wyoming, Steven M. Peterson, Jonathan P. Traylor, Moussa Guira Jan 2020

Groundwater Availability Of The Northern High Plains Aquifer In Colorado, Kansas, Nebraska, South Dakota, And Wyoming, Steven M. Peterson, Jonathan P. Traylor, Moussa Guira

United States Geological Survey: Publications

The Northern High Plains aquifer underlies about 93,000 square miles of Colorado, Kansas, Nebraska, South Dakota, and Wyoming and is the largest subregion of the nationally important High Plains aquifer. Irrigation, primarily using groundwater, has supported agricultural production since before 1940, resulting in nearly $50 billion in sales in 2012. In 2010, the High Plains aquifer had the largest groundwater withdrawals of any major aquifer system in the United States.Nearly one-half of those withdrawals were from the Northern High Plains aquifer, which has little hydrologic interaction with parts of the aquifer farther south. Land-surface elevation ranges from more than 7,400 …


Vertical Land Displacement Rates And Uncertainty In Hampton Roads, Va [Dataset], Brett Buzzanga, David P. S. Bekaert, Ben D. Hamlington, Simran S. Sangha Jan 2020

Vertical Land Displacement Rates And Uncertainty In Hampton Roads, Va [Dataset], Brett Buzzanga, David P. S. Bekaert, Ben D. Hamlington, Simran S. Sangha

CCPO Data Sets

These data contain vertical rates (mm/yr) of surface land displacements and their associated uncertainties from 2015-03-15 to 2019-06-01.

They are associated with Buzzanga, B. A., Bekaert, D. P. S., Hamlington, B. D., and Sanga, S. (2020), "Towards Sustained Monitoring of Subsidence at the Coast Using InSAR and GNSS: An Application in Hampton Roads, Virginia. Geophysical Research Letters.


Uptake, Metabolism, And Elimination Of Fungicides From Coated Wheat Seeds In Japanese Quail (Coturnix Japonica), Michael S. Gross, Thomas G. Bean, Michelle L. Hladik, Barnett A. Rattner, Kathryn M. Kuivila Jan 2020

Uptake, Metabolism, And Elimination Of Fungicides From Coated Wheat Seeds In Japanese Quail (Coturnix Japonica), Michael S. Gross, Thomas G. Bean, Michelle L. Hladik, Barnett A. Rattner, Kathryn M. Kuivila

United States Geological Survey: Staff Publications

Pesticides coated to the seed surface potentially pose an ecological risk to granivorous birds that consume incompletely buried or spilled seeds. To assess the toxicokinetics of seeds treated with current-use fungicides, Japanese quail ( Coturnix japonica) were orally dosed with commercially coated wheat seeds. Quail were exposed to metalaxyl, tebuconazole, and fludioxonil at either a low dose (0.0655, 0.0308, and 0.0328 mg/kg of body weight, respectively) or a high dose (0.196, 0.0925, and 0.0985 mg/kg of body weight, respectively). Fungicides were rapidly absorbed and distributed to tissues. Tebuconazole was metabolized into tert-butylhydroxy-tebuconazole. All compounds were eliminated to below detection limits …


Altitude Of The Potentiometric Surface In The Mississippi River Valley Alluvial Aquifer, Spring 2018, Virginia L. Mcguire, Ronald C. Seanor, William H. Asquith, Anna M. Nottmeier, David C. Smith, Roland W. Tollett, Wade H. Kress, Kellan R. Strauch Jan 2020

Altitude Of The Potentiometric Surface In The Mississippi River Valley Alluvial Aquifer, Spring 2018, Virginia L. Mcguire, Ronald C. Seanor, William H. Asquith, Anna M. Nottmeier, David C. Smith, Roland W. Tollett, Wade H. Kress, Kellan R. Strauch

United States Geological Survey: Publications

The Mississippi River Valley alluvial (MRVA) aquifer is an important surficial aquifer in the Mississippi Alluvial Plain (MAP) area. The aquifer is generally considered to be an unconfined aquifer (fig. 1; Clark and others, 2011), and withdrawals are primarily used for irrigation (Maupin and Barber, 2005). These groundwater withdrawals have resulted in substantial areas of water-level decline in parts of the aquifer. Concerns about water-level declines and the sustainability of the MRVA aquifer have prompted the U.S. Geological Survey (USGS), as part of the USGS Water Availability and Use Science Program and with assistance from other Federal, State, and local …


Water Quality Of Groundwater Used For Public Supply In Principal Aquifers Of The Western United States, Celia C. Rosencrans, Marylynn Musgrove Jan 2020

Water Quality Of Groundwater Used For Public Supply In Principal Aquifers Of The Western United States, Celia C. Rosencrans, Marylynn Musgrove

United States Geological Survey: Publications

Groundwater provides nearly half of the Nation’s drinking water. As the Nation’s population grows, the importance of (and need for) high-quality drinking-water supplies increases. As part of a national-scale effort to assess groundwater quality in principal aquifers (PAs) that supply most of the groundwater used for public supply, the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Project staff sampled six principal aquifers in the western United States between 2013 and 2017: (1) the Basin and Range carbonate-rock aquifers, (2) Basin and Range basin-fill aquifers, (3) Rio Grande aquifer system, (4) High Plains aquifer, (5) Colorado Plateaus aquifers, and (6) Columbia …


Estimated Groundwater Withdrawals From Principal Aquifers In The United States, 2015, John K. Lovelace, Martha G. Nielsen, Amy L. Read, Chid J. Murphy, Molly A. Maupin Jan 2020

Estimated Groundwater Withdrawals From Principal Aquifers In The United States, 2015, John K. Lovelace, Martha G. Nielsen, Amy L. Read, Chid J. Murphy, Molly A. Maupin

United States Geological Survey: Publications

In 2015, about 84,600 million gallons per day (Mgal/d) of groundwater were withdrawn in the United States for various uses including public supply, self-supplied domestic, industrial, mining, thermoelectric power, aquaculture, livestock, and irrigation. Of this total, about 94 percent (79,200 Mgal/d) was withdrawn from principal aquifers, which are defined as regionally extensive aquifers or aquifer systems that have the potential to be used as sources of water of suitable quality and quantity to meet various needs. The remaining 6 percent (5,400 Mgal/d) was withdrawn from other, nonprincipal aquifers in the United States. Sixty-six principal aquifers belonging to 5 major lithologic …


Estimating Abiotic Thresholds For Sagebrush Condition Class In The Western United States, Stephen Boyte, Bruce K. Wylie, Yingxin Gu, Donald J. Major Jan 2020

Estimating Abiotic Thresholds For Sagebrush Condition Class In The Western United States, Stephen Boyte, Bruce K. Wylie, Yingxin Gu, Donald J. Major

United States Geological Survey: Staff Publications

Sagebrush ecosystems of the western United States can transition from extended periods of relatively stable conditions to rapid ecological change if acute disturbances occur. Areas dominated by native sagebrush can transition from species-rich native systems to altered states where non-native annual grasses dominate, if resistance to annual grasses is low. The non-native annual grasses provide relatively little value to wildlife, livestock, and humans and function as fuel that increases fire frequency. The more land area covered by annual grasses, the higher the potential for fire, thus reducing the potential for native vegetation to reestablish, even when applying restoration treatments. Mapping …


Acoustic Space Occupancy: Combining Ecoacoustics And Lidar To Model Biodiversity Variation And Detection Bias Across Heterogeneous Landscapes, Danielle I. Rappaport, J. Andrew Royle, Douglas C. Morton Jan 2020

Acoustic Space Occupancy: Combining Ecoacoustics And Lidar To Model Biodiversity Variation And Detection Bias Across Heterogeneous Landscapes, Danielle I. Rappaport, J. Andrew Royle, Douglas C. Morton

United States Geological Survey: Staff Publications

There is global interest in quantifying changing biodiversity in human-modified landscapes. Ecoacoustics may offer a promising pathway for supporting multi-taxa monitoring, but its scalability has been hampered by the sonic complexity of biodiverse ecosystems and the imperfect detectability of animal-generated sounds. The acoustic signature of a habitat, or soundscape, contains information about multiple taxa and may circumvent species identification, but robust statistical technology for characterizing community-level attributes is lacking. Here, we present the Acoustic Space Occupancy Model, a flexible hierarchical framework designed to account for detection artifacts from acoustic surveys in order to model biologically relevant variation in acoustic space …


Human-Associated Species Dominate Passerine Communities Across The United States, Helen R. Sofaer, Curtis H. Flather, Catherine S. Jarnevich, Kristin P. Davis, Liba Pejchar Jan 2020

Human-Associated Species Dominate Passerine Communities Across The United States, Helen R. Sofaer, Curtis H. Flather, Catherine S. Jarnevich, Kristin P. Davis, Liba Pejchar

United States Geological Survey: Staff Publications

Aim: Human development and agriculture can have transformative and homogenizing effects on natural systems, shifting the composition of ecological communities towards non-native and native species that tolerate or thrive under human-dominated conditions. These impacts cannot be fully captured by summarizing species presence, as they include dramatic changes to patterns of species abundance. However, how human land use patterns and species invasions intersect to shape patterns of abundance and dominance within ecological communities is poorly understood even in well-known taxa.

Location: Conterminous United States.

Time period: 2010–2012.

Major taxa studied: Passeriformes.

Methods: We analyse continental-scale monitoring data to study the proportional …


Ecosystem Processes, Land Cover, Climate, And Human Settlement Shape Dynamic Distributions For Golden Eagle Across The Western Us, J.D. Tack, Barry R. Noon, Zachary Bowen, Brad C. Fedy Jan 2020

Ecosystem Processes, Land Cover, Climate, And Human Settlement Shape Dynamic Distributions For Golden Eagle Across The Western Us, J.D. Tack, Barry R. Noon, Zachary Bowen, Brad C. Fedy

United States Geological Survey: Staff Publications

Species–environment relationships for highly mobile species outside of the breeding season are often highly dynamic in response to the collective effects of everchanging climatic conditions, food resources, and anthropogenic disturbance. Capturing dynamic space-use patterns in a model-based framework is critical as model inference often drives place-based conservation planning. We applied dynamic occupancy models to broad-scale golden eagle Aquila chrysaetos survey data collected annually from 2006 to 2012 during the late summer post-fledging period in the western US. We defined survey sites as 10 km transect segments with a 1 km buffer on either transect side (n = 3540). Derived estimates …


Human-Associated Species Dominate Passerine Communities Across The United States, Helen R. Sofaer, Curtis H. Flather, Catherine S. Jarnevich, Kristin P. Davis Jan 2020

Human-Associated Species Dominate Passerine Communities Across The United States, Helen R. Sofaer, Curtis H. Flather, Catherine S. Jarnevich, Kristin P. Davis

United States Geological Survey: Staff Publications

Aim: Human development and agriculture can have transformative and homogenizing effects on natural systems, shifting the composition of ecological communities towards non-native and native species that tolerate or thrive under human-dominated conditions. These impacts cannot be fully captured by summarizing species presence, as they include dramatic changes to patterns of species abundance. However, how human land use patterns and species invasions intersect to shape patterns of abundance and dominance within ecological communities is poorly understood even in well-known taxa.

Location: Conterminous United States.

Time period: 2010–2012.

Major taxa studied: Passeriformes.

Methods: We analyse continental-scale monitoring data to study the proportional …


Acoustic Space Occupancy: Combining Ecoacoustics And Lidar To Model Biodiversity Variation And Detection Bias Across Heterogeneous Landscapes, Danielle I. Rappaport, J. Andrew Royle, Douglas C. Morton Jan 2020

Acoustic Space Occupancy: Combining Ecoacoustics And Lidar To Model Biodiversity Variation And Detection Bias Across Heterogeneous Landscapes, Danielle I. Rappaport, J. Andrew Royle, Douglas C. Morton

United States Geological Survey: Staff Publications

There is global interest in quantifying changing biodiversity in human-modified landscapes. Ecoacoustics may offer a promising pathway for supporting multi-taxa monitoring, but its scalability has been hampered by the sonic complexity of biodiverse ecosystems and the imperfect detectability of animal-generated sounds. The acoustic signature of a habitat, or soundscape, contains information about multiple taxa and may circumvent species identification, but robust statistical technology for characterizing community-level attributes is lacking. Here, we present the Acoustic Space Occupancy Model, a flexible hierarchical framework designed to account for detection artifacts from acoustic surveys in order to model biologically relevant variation in acoustic space …


Characterization Of Pallid Sturgeon (Scaphirhynchus Albus) Spawning Habitat In The Lower Missouri River, Caroline M. Elliott, Aaron J. Delonay, Kimberly Chojnacki, Robert B. Jacobson Jan 2020

Characterization Of Pallid Sturgeon (Scaphirhynchus Albus) Spawning Habitat In The Lower Missouri River, Caroline M. Elliott, Aaron J. Delonay, Kimberly Chojnacki, Robert B. Jacobson

United States Geological Survey: Staff Publications

Acipenseriformes (sturgeons and paddlefish) globally have declined throughout their range due to river fragmentation, habitat loss, overfishing, and degradation of water quality. In North America, pallid sturgeon (Scaphirhynchus albus) populations have experienced poor to no recruitment, or substantial levels of hybridization with the closely related shovelnose sturgeon (S. platorynchus). The Lower Missouri River is the only portion of the species’ range where successful reproduction and recruitment of genetically pure pallid sturgeon have been documented. This paper documents spawning habitat and behavior on the Lower Missouri River, which comprises over 1,300 km of unfragmented river habitat. The …


Late Quaternary Sea-Level History Of Saipan, Commonwealth Of The Northern Mariana Islands, Usa: A Test Of Tectonic Uplift And Glacial Isostatic Adjustment Models, Daniel R. Muhs, Eugene S. Schweig, Kathleen R. Simmons Jan 2020

Late Quaternary Sea-Level History Of Saipan, Commonwealth Of The Northern Mariana Islands, Usa: A Test Of Tectonic Uplift And Glacial Isostatic Adjustment Models, Daniel R. Muhs, Eugene S. Schweig, Kathleen R. Simmons

United States Geological Survey: Staff Publications

In 1979, S. Uyeda and H. Kanamori proposed a tectonic model with two end members of a subduction-boundary continuum: the “Chilean” type (shallow dip of the subducting plate, great thrust events, compression, and uplift of the overriding plate) and a “Mariana” type (steep dip of the subducting plate, no great thrust events, tension, and no uplift). This concept has been used to explain variable rates of Quaternary uplift around the Pacific Rim, yet no uplift rates have been determined for the Mariana Islands themselves, one of the end members in this model. We studied the late Quaternary Tanapag Limestone, which …


The Quartz Of Arkansas: Geology, History And Legend, Thomas R. Paradise Jan 2020

The Quartz Of Arkansas: Geology, History And Legend, Thomas R. Paradise

Geosciences Faculty Publications and Presentations

Quartz Crystals has been treasured and utilized through history, and this chapter addresses its many uses, mineralogy, history, and legend over time...


Evidence Of Limited Recruitment Of Pallid Sturgeon In The Lower Missouri River, Kirk D. Steffensen, Kimberly Chojnacki, Jeffrey A. Kalie, Meredith L. Bartron, Edward J. Heist, Kyle R. Winders, Nathan C. Loecker, Wyatt J. Doyle, Timothy L. Welker Dec 2019

Evidence Of Limited Recruitment Of Pallid Sturgeon In The Lower Missouri River, Kirk D. Steffensen, Kimberly Chojnacki, Jeffrey A. Kalie, Meredith L. Bartron, Edward J. Heist, Kyle R. Winders, Nathan C. Loecker, Wyatt J. Doyle, Timothy L. Welker

United States Geological Survey: Staff Publications

Pallid Sturgeon Scaphirhynchus albus are endemic to the Missouri and Mississippi river basins and are rare throughout their range. The species was listed as federally endangered with little to no evidence of natural recruitment. Since population augmentation was initiated as a recovery objective in the early 1990s, thousands of hatchery-origin Pallid Sturgeon have been stocked in the lower Missouri River (Gavins Point Dam [river kilometer 1,305.1] to the confluence of the Mississippi River [river kilometer 0.0]). Efforts to discriminate natural reproduction and recruitment of wild-origin Pallid Sturgeon from hatchery-origin fish has been hampered by tag loss in hatchery-origin sturgeon, inconsistent …


Evidence Of Variable Climate And Resources During The Late Pleistocene And Holocene At Gona, Ethiopia, Marie White Nov 2019

Evidence Of Variable Climate And Resources During The Late Pleistocene And Holocene At Gona, Ethiopia, Marie White

Steeplechase: An ORCA Student Journal

The African Humid Period (AHP) spanned a period of approximately 15 to 5 thousand years ago (ka) and resulted in Northern and Eastern Africa being wetter than today. This climate change event impacted flora, fauna, and humans to an unknown extent. Much of the work on the AHP across Eastern Africa utilizes lacustrine and marine proxies rather than river-based (fluvial). Gona, located in the Afar region of Ethiopia, is known for its extensive archaeological and fossil records in fluvial deposits. However, the paleoenvironment of the AHP at Gona has not been investigated. This study uses stratigraphy, geochronology, and paleopedology to …


Seismic Evidence For Significant Melt Beneath The Long Valley Caldera, California, Usa, Ashton F. Flinders, David R. Shelly, Philip B. Dawson, David P. Hill, Barbara Tripoli, Yang Shen Nov 2019

Seismic Evidence For Significant Melt Beneath The Long Valley Caldera, California, Usa, Ashton F. Flinders, David R. Shelly, Philip B. Dawson, David P. Hill, Barbara Tripoli, Yang Shen

United States Geological Survey: Staff Publications

A little more than 760 ka ago, a supervolcano on the eastern edge of California (United States) underwent one of North America’s largest Quaternary explosive eruptions. Over this ~6-day-long eruption, pyroclastic flows blanketed the surrounding ~50 km with more than 1400 km3 of the now-iconic Bishop Tuff, with ashfall reaching as far east as Nebraska. Collapse of the volcano’s magma reservoir created the restless Long Valley Caldera. Although no rhyolitic eruptions have occurred in 100 k.y., beginning in 1978, ongoing uplift suggests new magma may have intruded into the reservoir. Alternatively, the reservoir could be approaching final crystallization, with present-day …


Little Islands Recording Global Events: Late Quaternary Sea Level History And Paleozoogeography Of Santa Barbara And Anacapa Islands, Channel Islands National Park, California, Daniel R. Muhs, Lindsey T. Groves Sep 2019

Little Islands Recording Global Events: Late Quaternary Sea Level History And Paleozoogeography Of Santa Barbara And Anacapa Islands, Channel Islands National Park, California, Daniel R. Muhs, Lindsey T. Groves

United States Geological Survey: Staff Publications

Marine terraces are common on the Pacific Coast of North America and record interglacial high-sea stands superimposed on either stable or tectonically rising crustal blocks. Despite many years of study of these landforms in southern California, little work on terraces has been conducted on the two smallest of the California Channel Islands, Santa Barbara Island (SBI) and Anacapa Island (ANA). Presented here are new field and laboratory data on the ages, paleontology, and sea level history of marine terraces of these two islands. On both islands, the lowest marine terraces have shoreline angle elevations of ~11 m above sea level. …


Promoting Change In Common Tern (Sterna Hirundo) Nest Site Selection To Minimize Construction Related Disturbance., Peter C. Mcgowan, Jeffery D. Sullivan, Carl R. Callahan, William Schultz, Jennifer L. Wall, Diann J. Prosser Sep 2019

Promoting Change In Common Tern (Sterna Hirundo) Nest Site Selection To Minimize Construction Related Disturbance., Peter C. Mcgowan, Jeffery D. Sullivan, Carl R. Callahan, William Schultz, Jennifer L. Wall, Diann J. Prosser

United States Geological Survey: Staff Publications

Due to the many challenges facing waterbird populations (Jia et al. 2018, Wetlands International 2018), it has become common practice to limit disturbance to breeding colonies whenever possible to maximize reproductive success. While this may require often unpopular management techniques including beach closures (Jorgensen et al. 2015, Mayo et al. 2015) and predator removal (Neuman et al. 2004, Stocking et al. 2017), such actions are sometimes necessary for the success of the colony. However, there are instances when eliminating disturbance is not possible and birds must be attracted to a new site. A common method for attracting waterbirds to a …


Comparing Structure From Motion Photogrammetry And Computer Vision For Low-Cost 3d Cave Mapping: Tipton-Haynes Cave, Tennessee, Clinton Elmore Aug 2019

Comparing Structure From Motion Photogrammetry And Computer Vision For Low-Cost 3d Cave Mapping: Tipton-Haynes Cave, Tennessee, Clinton Elmore

Electronic Theses and Dissertations

Natural caves represent one of the most difficult environments to map with modern 3D technologies. In this study I tested two relatively new methods for 3D mapping in Tipton-Haynes Cave near Johnson City, Tennessee: Structure from Motion Photogrammetry and Computer Vision using Tango, an RGB-D (Red Green Blue and Depth) technology. Many different aspects of these two methods were analyzed with respect to the needs of average cave explorers. Major considerations were cost, time, accuracy, durability, simplicity, lighting setup, and drift. The 3D maps were compared to a conventional cave map drafted with measurements from a modern digital survey instrument …


Management Regime And Habitat Response Influence Abundance Of Regal Fritillary (Speyeria Idalia) In Tallgrass Prairie, K. Mccullough, G. Albanese, D.A. Haukos, A.M. Ricketts, S. Stratton Jul 2019

Management Regime And Habitat Response Influence Abundance Of Regal Fritillary (Speyeria Idalia) In Tallgrass Prairie, K. Mccullough, G. Albanese, D.A. Haukos, A.M. Ricketts, S. Stratton

United States Geological Survey: Staff Publications

The >2,570,000-ha Flint Hills ecoregion of Kansas, USA, harbors the largest remaining contiguous tract of tallgrass prairie in North America, a unique system, as the remainder of North America’s tallgrass prairie has succumbed to development and conversion. Consequently, the loss and degradation of tallgrass prairie has reduced populations of many North American prairie-obligate species including the regal fritillary (Speyeria idalia) butterfly. Population abundance and occupied range of regal fritillary have declined >99%, restricting many populations to isolated, remnant patches of tallgrass prairie. Such extensive decline has resulted in consideration of the regal fritillary for protection under the Endangered Species Act. …


Identifying Characteristics Of Actionable Science For Drought Planning And Adaptation, Adam Wilke, Amanda Cravens Jul 2019

Identifying Characteristics Of Actionable Science For Drought Planning And Adaptation, Adam Wilke, Amanda Cravens

United States Geological Survey: Publications

Changing climate conditions can make water management planning and drought preparedness decisions more complicated than ever before. Federal and State natural resource managers can no longer rely solely on historical trends as a baseline and thus are in need of science that is relevant to their specific needs to inform important planning decisions. Questions remain, however, regarding the most effective and efficient methods for extending scientific knowledge and products into management and decision-making. This project analyzed two unique cases of water management to better understand how science can be translated into resource management actions and decision-making, focusing particularly on how …


Detrital Zircon Geochronology Of Paleoproterozoic Sedimentary Rocks From The Upper Huronian Supergroup, Canada, Carolyn M. Hill, Don W. Davis, Patricia L. Corcoran Jun 2019

Detrital Zircon Geochronology Of Paleoproterozoic Sedimentary Rocks From The Upper Huronian Supergroup, Canada, Carolyn M. Hill, Don W. Davis, Patricia L. Corcoran

Western Research Forum

The Huronian Supergroup is a well-known succession of primarily sedimentary rocks exposed north of Lake Huron. Deposition of the succession is constrained between 2450 and 2220 Ma (million years), which corresponds with Earth’s rise of atmospheric oxygen, however the depositional timing of the uppermost formations cannot be refined further due to a lack of interbedded volcanic rocks. A geochronological study of detrital zircon grains from sandstone and claystone beds from the two youngest Huronian formations, the Gordon Lake and Bar River formations, was completed in order to confine the maximum age of deposition.

Zircon is a mineral that commonly forms …


The Antiquity Of The Sahara Desert: New Evidence From The Mineralogy And Geochemistry Of Pliocene Paleosols On The Canary Islands, Spain, Daniel R. Muhs, Joaquín Meco, James R. Budahn, Gary L. Skipp, Juan F. Betancort, Alejandro Lomoschitz Jun 2019

The Antiquity Of The Sahara Desert: New Evidence From The Mineralogy And Geochemistry Of Pliocene Paleosols On The Canary Islands, Spain, Daniel R. Muhs, Joaquín Meco, James R. Budahn, Gary L. Skipp, Juan F. Betancort, Alejandro Lomoschitz

United States Geological Survey: Staff Publications

The Sahara is the largest warm desert in the world, but its age has been controversial, with estimates ranging from Miocene to Holocene. Mineralogical and geochemical data show that paleosols of Pliocene to mid- Pleistocene age on Fuerteventura and Gran Canaria in the Canary Islands have developed in part from inputs of dust from Africa. These paleosols contain quartz and mica, minerals that are abundant in African dust but are rare in the basaltic rocks that dominate the Canary Islands. Trace elements with minimal mobility, Sc, Cr, Hf, Th, and Ta as well as the rare earth elements, show that …


Tropospheric And Ionospheric Anomalies Induced By Volcanic And Saharan Dust Events As Part Of Geosphere Interaction Phenomena, Valerio Tramutoli, Francesco Marchese, Alfredo Falconieri, Carolina Filizzola, Nicola Genzano, Katsumi Hattori, Mariano Lisi, Jann-Yenq Liu, Dimitar Ouzounov, Michel Parrot, Nicola Pergola, Sergey Pulinets Apr 2019

Tropospheric And Ionospheric Anomalies Induced By Volcanic And Saharan Dust Events As Part Of Geosphere Interaction Phenomena, Valerio Tramutoli, Francesco Marchese, Alfredo Falconieri, Carolina Filizzola, Nicola Genzano, Katsumi Hattori, Mariano Lisi, Jann-Yenq Liu, Dimitar Ouzounov, Michel Parrot, Nicola Pergola, Sergey Pulinets

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this work, we assessed the possible relation of ionospheric perturbations observed by Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions (DEMETER), Global Positioning System total electron content (GPS TEC), National Oceanic and Atmospheric Administration (NOAA)-derived outgoing longwave-Earth radiation (OLR), and atmospheric chemical potential (ACP) measurements, with volcanic and Saharan dust events identified by ground and satellite-based medium infrared/thermal infrared (MIR/TIR) observations. The results indicated that the Mt. Etna (Italy) volcanic activity of 2006 was probably responsible for the ionospheric perturbations revealed by DEMETER on 4 November and 6 December and by GPS TEC observations on 4 November and 12 …


Growth, Condition, And Trophic Relations Of Stocked Trout In Southern Appalachian Mountain Streams, Jesse R. Fischer, Thomas J. Kwak, H. Jared Flowers, W. Gregory Cope, Jacob M. Rash, Douglas A. Besler Apr 2019

Growth, Condition, And Trophic Relations Of Stocked Trout In Southern Appalachian Mountain Streams, Jesse R. Fischer, Thomas J. Kwak, H. Jared Flowers, W. Gregory Cope, Jacob M. Rash, Douglas A. Besler

United States Geological Survey: Staff Publications

Stream trout fisheries are among the most popular and valuable in the United States, but many are dependent on hatcheries to sustain fishing and harvest. Thus, understanding the ecology of hatchery‐reared trout stocked in natural environments is fundamental to management. We evaluated the growth, condition, and trophic relations of Brook Trout Salvelinus fontinalis, Brown Trout Salmo trutta, and Rainbow Trout Oncorhynchus mykiss that were stocked in southern Appalachian Mountain streams in western North Carolina. Stocked and wild (naturalized) trout were sampled over time (monthly; September 2012–June 2013) to compare condition and diet composition and to evaluate temporal dynamics of trophic …


Notes And Discussion Piece: Status Of The Topeka Shiner In Iowa, Clay L. Pierce, Nicholas T. Simpson, Alexander P. Bybel, Courtney L. Zambory, Michael J. Weber, Kevin J. Roe Apr 2019

Notes And Discussion Piece: Status Of The Topeka Shiner In Iowa, Clay L. Pierce, Nicholas T. Simpson, Alexander P. Bybel, Courtney L. Zambory, Michael J. Weber, Kevin J. Roe

United States Geological Survey: Staff Publications

The Topeka shiner Notropis topeka is native to Iowa, Kansas, Minnesota, Missouri, Nebraska, and South Dakota and has been federally listed as endangered since 1998. Our goals were to determine the present distribution and qualitative status of Topeka shiners throughout its current range in Iowa and characterize the extent of decline in relation to its historic distribution. We compared the current (2016–2017) distribution to distributions portrayed in three earlier time periods. In 2016–2017 Topeka shiners were found in 12 of 20 HUC10 watersheds where they occurred historically. Their status was classified as stable in 21% of the HUC10 watersheds, possibly …


Suspended Sediment Transport Revealed By Patterns In Turbidity And Electrical Conductivity Curves In Three Cave Systems In Missouri, Usa., Caroline M. Mierzejewski Mar 2019

Suspended Sediment Transport Revealed By Patterns In Turbidity And Electrical Conductivity Curves In Three Cave Systems In Missouri, Usa., Caroline M. Mierzejewski

LSU Master's Theses

In cave streams, the movement of sediment as suspended and bed loads are linked to the occurrence of precipitation events on the surface. During precipitation events, the discharge of the streams in the basin increases. As those surface streams flow into cave streams via sinkholes or fissures, the discharge in cave streams increase. In addition to changes in discharge, the response of the surface and cave streams to precipitation include changes in turbidity and electrical conductivity of the stream water.

Changes in turbidity (Tu), electrical conductivity (EC), and discharge (Q) of water in the cave stream can be used to …


Flow Alteration-Ecology Relationships In Ozark Highland Streams: Consequences For Fish, Crayfish And Macroinvertebrate Assemblages, Dustin Thomas Lynch, Douglas R. Leasure, Daniel D. Magoulick Mar 2019

Flow Alteration-Ecology Relationships In Ozark Highland Streams: Consequences For Fish, Crayfish And Macroinvertebrate Assemblages, Dustin Thomas Lynch, Douglas R. Leasure, Daniel D. Magoulick

United States Geological Survey: Staff Publications

We examined flowalteration-ecology relationships in benthic macroinvertebrate, fish, and crayfish assemblages in Ozark Highland streams, USA, over two years with contrasting environmental conditions, a drought year (2012) and a flood year (2013). We hypothesized that: 1) there would be temporal variation in flow alteration-ecology relationships between the two years, 2) flow alteration-ecology relationshipswould be stronger during the drought year vs the flood year, and 3) fish assemblages would show the strongest relationships with flow alteration. We used a quantitative richest-targeted habitat (RTH) method and a qualitative multihabitat (QMH) method to collect macroinvertebrates at 16 USGS gaged sites during both years. …