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Articles 12421 - 12450 of 17799
Full-Text Articles in Entire DC Network
Building Up Biogeography: Pattern To Process, William D. Pearse, A. Marcia Barbosa, Susanne A. Fritz, Sally A. Keith, Luke J. Harmon, John Harte, Daniele Silvestro, Xiao Xiao, T. Jonathan Davies
Building Up Biogeography: Pattern To Process, William D. Pearse, A. Marcia Barbosa, Susanne A. Fritz, Sally A. Keith, Luke J. Harmon, John Harte, Daniele Silvestro, Xiao Xiao, T. Jonathan Davies
Ecology Center Publications
Linking pattern to process across spatial and temporal scales has been a key goal of the field of biogeography. In January 2017, the 8th biennial conference of the International Biogeography Society sponsored a symposium on Building up biogeography—process to pattern that aimed to review progress towards this goal. Here we present a summary of the symposium, in which we identified promising areas of current research and suggested future research directions. We focus on (1) emerging types of data such as behavioral observations and ancient DNA, (2) how to better incorporate historical data (such as fossils) to move beyond what we …
Investigating Uranium Incorporation In Modern Carbonates By Sequential Extraction: Applied To The Permian - Triassic Boundary In Lung Cam, Vietnam, Christopher Michael Wray
Investigating Uranium Incorporation In Modern Carbonates By Sequential Extraction: Applied To The Permian - Triassic Boundary In Lung Cam, Vietnam, Christopher Michael Wray
LSU Master's Theses
The Uranium (U) isotopic system can be used to model the extent of global-scale ocean anoxia by utilizing the 238U/235U ratios as a paleo-redox indicator (δ238U). While recent studies have shown promise with the use of this novel proxy, variability is seen in modern carbonate sediment samples suggesting that more work is needed in order to understand elemental U uptake during early marine diagenesis. This thesis utilizes a sequential extraction methodology in order to understand the distribution of authigenic U within carbonate sediments.
This thesis consists of four parts, (1) an evaluation and modification of a sequential extraction methodology for …
Devonian Stromatoporoid Interactions At The Falls Of The Ohio State Park, Clarksville, Indiana, Morgan Sierra Hall
Devonian Stromatoporoid Interactions At The Falls Of The Ohio State Park, Clarksville, Indiana, Morgan Sierra Hall
Undergraduate Theses
Stromatoporoids are calcitic sponges that occurred in the fossil record from the Early Ordovician to Late Devonian period. These sponges interacted with other organisms, especially rugose and tabulate corals. Some corals appear to benefit from the rigidity of stromatoporoids in response to turbulent waters. Stromatoporoids and many corals went extinct during the Frasnian-Famennian crisis when paleoenvironmental parameters were shifting. Studying the relationships between these taxa may provide insight to their vulnerability during the extinction.
This research was performed at the Falls of the Ohio in Clarksville, Indiana. Organisms in the Coral Zone were studied using transect sampling. Each fossil along …
An Assessment Of Atmospheric And Meteorological Factors Regulating Red Sea Phytoplankton Growth, Wenzhao Li, Hesham El-Askary, Mohamed A. Qurban, Emmanouil Proestakis, Michael J. Garay, Olga V. Kalishnikova, Vassilis Amiridis, Antonis Gkikas, Eleni Marinou, Thomas Piechota, K. P. Manikandan
An Assessment Of Atmospheric And Meteorological Factors Regulating Red Sea Phytoplankton Growth, Wenzhao Li, Hesham El-Askary, Mohamed A. Qurban, Emmanouil Proestakis, Michael J. Garay, Olga V. Kalishnikova, Vassilis Amiridis, Antonis Gkikas, Eleni Marinou, Thomas Piechota, K. P. Manikandan
Mathematics, Physics, and Computer Science Faculty Articles and Research
This study considers the various factors that regulate nutrients supply in the Red Sea. Multi-sensor observation and reanalysis datasets are used to examine the relationships among dust deposition, sea surface temperature (SST), and wind speed, as they may contribute to anomalous phytoplankton blooms, through time-series and correlation analyses. A positive correlation was found at 0–3 months lag between chlorophyll-a (Chl-a) anomalies and dust anomalies over the Red Sea regions. Dust deposition process was further examined with dust aerosols’ vertical distribution using satellite lidar data. Conversely, a negative correlation was found at 0–3 months lag between SST anomalies …
Body Size Downgrading Of Mammals Over The Late Quaternary, Felisa A. Smith, Rosemary E. Elliott Smith, S. Kathleen Lyons, Jonathan L. Payne
Body Size Downgrading Of Mammals Over The Late Quaternary, Felisa A. Smith, Rosemary E. Elliott Smith, S. Kathleen Lyons, Jonathan L. Payne
School of Biological Sciences: Faculty Publications
Since the late Pleistocene, large-bodied mammals have been extirpated from much of Earth. Although all habitable continents once harbored giant mammals, the few remaining species are largely confined to Africa. This decline is coincident with the global expansion of hominins over the late Quaternary. Here, we quantify mammalian extinction selectivity, continental body size distributions, and taxonomic diversity over five time periods spanning the past 125,000 years and stretching approximately 200 years into the future. We demonstrate that size-selective extinction was already under way in the oldest interval and occurred on all continents, within all trophic modes, and across all time …
Structural Classification Using Aeromagnetic Data And Pseudogravity Transforms: A Case Study Of Pategi Area Of Bida Basin, Nigeria, Ayodele K Olawuyi, Halima M Amir, Mkabwa Lk Manoko
Structural Classification Using Aeromagnetic Data And Pseudogravity Transforms: A Case Study Of Pategi Area Of Bida Basin, Nigeria, Ayodele K Olawuyi, Halima M Amir, Mkabwa Lk Manoko
Tanzania Journal of Science
The structural classification with 3D Euler deconvolution method in the Pategi area, a transition environment between the Basement complex rocks of the southwestern Nigeria and the Sedimentary rocks of the Nupe Basin was carried out. It was aimed at identification of the structural features responsible for the hydrogeology and mineralization potentials of the area. This work involves the qualitative and quantitative analysis of aeromagnetic data and pseudogravity transforms using Oasis MontajTM. The 3-D Euler deconvolution of the acquired aeromagnetic data and pseudogravity transforms using Oasis montajTM software and the geologic information on this area was employed in the structural classification …
Speciation Of Lead, Chromium, Cadmium, Copper And Zinc In Sediments And Plants Along Msimbazi River In Dar Es Salaam, Tanzania, Faustin N Ngassapa, Othman C Othman, David Mihayo, Kessy F Kilulya
Speciation Of Lead, Chromium, Cadmium, Copper And Zinc In Sediments And Plants Along Msimbazi River In Dar Es Salaam, Tanzania, Faustin N Ngassapa, Othman C Othman, David Mihayo, Kessy F Kilulya
Tanzania Journal of Science
The speciation of lead, chromium, cadmium, copper and zinc in sediments and plants (pumpkin) along Msimbazi River in Dar es Salaam were determined using Atomic Absorption Spectrophotometry. Results in sediments indicated that the heavy metal contents (mg/kg) in the form of total trace metals ranged from 50.34 to 161.63 for Pb, 68.38 to 501.85 for Zn, 18.43 to 66.61 for Cu, 20.93 to 76.46 for Cr and BDL to 0.23 for Cd. The contents (mg/kg) in the form of metals bound to organic matter ranged from 18.24 to 46.58 for Pb, 27.64 to 228.62 for Zn, 3.55 to 16.76 for …
Assessment Of Water Quality Variation In Rivers Through Comparative Index Technique And Its Reliability For Decision Making, Aldo Kitalika, Revocatus Machunda, Hans Komakech, Karoli N Njau
Assessment Of Water Quality Variation In Rivers Through Comparative Index Technique And Its Reliability For Decision Making, Aldo Kitalika, Revocatus Machunda, Hans Komakech, Karoli N Njau
Tanzania Journal of Science
The National Sanitation Foundation (NSF) and Weighed Arithmetic Index (WAI) methods for water quality index (WQI) have been studied to evaluate their reliability in water quality assessment in rivers. Water samples were collected in various GPS predetermined points in Temi, Nduruma, Tengeru and Maji ya Chai rivers-Tanzania during wet and dry seasons and were analyzed for several water quality parameters using standard methods as per APHA. Medium to excellent water qualities were observed for pristine environment in three rivers except Maji ya Chai under NSF and WIA methods, respectively. Excellent water quality was observed in the pristine environment of Temi …
Gymnosperms On The Edge, Félix Forest, Justin Moat, Elisabeth Baloch, Neil A. Brummitt, Steve P. Bachman, Steffi Ickert-Bond, Peter M. Hollingsworth, Aaron Liston, Damon P. Little, Sarah Mathews, Hardeep Rai, Catarina Rydin, Dennis W. Stevenson, Philip Thomas, Sven Buerki
Gymnosperms On The Edge, Félix Forest, Justin Moat, Elisabeth Baloch, Neil A. Brummitt, Steve P. Bachman, Steffi Ickert-Bond, Peter M. Hollingsworth, Aaron Liston, Damon P. Little, Sarah Mathews, Hardeep Rai, Catarina Rydin, Dennis W. Stevenson, Philip Thomas, Sven Buerki
Wildland Resources Faculty Publications
Driven by limited resources and a sense of urgency, the prioritization of species for conservation has been a persistent concern in conservation science. Gymnosperms (comprising ginkgo, conifers, cycads, and gnetophytes) are one of the most threatened groups of living organisms, with 40% of the species at high risk of extinction, about twice as many as the most recent estimates for all plants (i.e. 21.4%). This high proportion of species facing extinction highlights the urgent action required to secure their future through an objective prioritization approach. The Evolutionary Distinct and Globally Endangered (EDGE) method rapidly ranks species based on their evolutionary …
Modeling And Implementation Of Basic Digital Ocean Construction Framework, Wanwu Li, Lin Liu, Jiajing Li, Peng Cheng, Zhaohui Liu
Modeling And Implementation Of Basic Digital Ocean Construction Framework, Wanwu Li, Lin Liu, Jiajing Li, Peng Cheng, Zhaohui Liu
Journal of Marine Science and Technology–Taiwan
This paper presents a new framework for Digital Ocean construction that includes a supporting layer, basic layer, data layer, service layer, application layer, and assurance layer; the functional composition and architecture of each layer are described. The model framework realizes effective integration, exchange, and sharing of marine information, basic geographical information, and closely related economic and social information through open architecture and a standardized service mode. The research results revealed that the proposed framework overcomes the defects inherent in the existing Digital Ocean systems. Therefore, it serves as a basic framework for policymakers, provides unified technical architecture for constructing a …
Long-Term Remote Monitoring The Effects Of Rainfall And Agricultural Non-Point Sources Pollution On The Surface Waters Quality In Lake Taihu, Shan-Lin Tong, Chen-Feng Cui, Yan-Ling Bai, Yu Sun, Xiao-Hui Zheng
Long-Term Remote Monitoring The Effects Of Rainfall And Agricultural Non-Point Sources Pollution On The Surface Waters Quality In Lake Taihu, Shan-Lin Tong, Chen-Feng Cui, Yan-Ling Bai, Yu Sun, Xiao-Hui Zheng
Journal of Marine Science and Technology–Taiwan
The transport of pollutants into freshwater resources depends on the relationships between pesticide/fertilizer application, local topography and rainfall. These relationships are investigated at Lake Taihu, China, where the cropland around the basin is devoted to growing rice. Our aim is to study the effects of the rainfall and non-point source contamination on surface water quality, with a specific focus on Nitrate Potassium Permanganate Chemical Oxidant (CODMn) and Nitrates (NH3-N), and using satellite remote sensing to construct a pollution estimation model by using satellite data and surface data from 7 monitoring station surveys in 2008-2015. Comparing measured values and remote sensing …
Hawai'i Wildlife Fund V. County Of Maui, Lowell J. Chandler
Hawai'i Wildlife Fund V. County Of Maui, Lowell J. Chandler
Public Land & Resources Law Review
In Hawai’i Wildlife Fund v. County of Maui, the Ninth Circuit held that the plain language of the Clean Water Act provides jurisdiction over indirect discharges of pollutants from a point source into groundwater that is shown to be connected to navigable waters. The court found that studies confirmed pollutants entering the Pacific Ocean were fairly traceable to the County of Maui’s sewage disposal wells. In affirming the district court’s ruling, the Ninth Circuit held that Maui County violated the Clean Water Act by discharging pollutants into a navigable water without the required permit. The court also concluded the …
Imidacloprid Sorption And Transport In Cropland, Grass Buffer, And Riparian Buffer Soils, Laura E. Satkowski, Keith W. Goyne, Stephen H. Anderson, Robert N. Lerch, Elisabeth B. Webb, Daniel D. Snow
Imidacloprid Sorption And Transport In Cropland, Grass Buffer, And Riparian Buffer Soils, Laura E. Satkowski, Keith W. Goyne, Stephen H. Anderson, Robert N. Lerch, Elisabeth B. Webb, Daniel D. Snow
Daugherty Water for Food Global Institute: Faculty Publications
An understanding of neonicotinoid sorption and transport in soil is critical for determining and mitigating environmental risk associated with the most widely used class of insecticides. The objective of this study was to evaluate mobility and transport of the neonicotinoid imidacloprid (ICD) in soils collected from cropland, grass vegetative buffer strip (VBS), and riparian VBS soils. Soils were collected at six randomly chosen sites within grids that encompassed all three land uses. Single-point equilibrium batch sorption experiments were conducted using radio-labeled (14C) ICD to determine solid–solution partition coefficients (Kd). Column experiments were conducted using soils collected …
2018 Senior Research Symposium, Otterbein University Department Of Biology & Earth Science
2018 Senior Research Symposium, Otterbein University Department Of Biology & Earth Science
Biology and Earth Science Student Scholarship
This is the schedule for the 2018 Senior Research Symposium and the abstracts from each presentation.
Moonmilk As A Human And Veterinary Medicine: Evidence Of Past Artisan Mining In Caves Of The Austrian Alps, Christoph Spötl
Moonmilk As A Human And Veterinary Medicine: Evidence Of Past Artisan Mining In Caves Of The Austrian Alps, Christoph Spötl
International Journal of Speleology
The use of moonmilk for medical and other purposes in the Alps is documented since the 16th century. This article reviews speleological reports and sparse historical accounts about the extraction of moonmilk from 18 caves in the Eastern Alps of Austria in an artisan mining style. One such example from a cave in Tyrol is documented in detail, where moonmilk was mined until the beginning of the 20th century and which, due to its remote location, uniquely preserved traces of both the mining and processing style.
T.D.A. Cockerell (1866–1948) Of The University Of Colorado: His Contributions To The Natural History Of The California Islands And The Establishment Of Channel Islands National Monument, Daniel R. Muhs
United States Geological Survey: Staff Publications
Theodore Dru Alison Cockerell was a naturalist at the University of Colorado from 1904 to 1947 and studied botany, zoology, and paleontology in North and South America, Asia, Australia, Africa, and Europe. In the latter part of his career, he studied the California islands and published many papers on their natural history, 16 of them in four years (1937–1940). He made important contributions to the natural history of the islands in four distinct ways: entomology of the islands, including identification of a number of new species of bees; discovery of fossil marine invertebrate faunas and recognition that the zoogeography of …
Sigma Gamma Epsilon Student Research Poster Session, Geological Society Of America Meeting 2017, Seattle, Washington, Usa, Paula Even
The Compass: Earth Science Journal of Sigma Gamma Epsilon
The Sigma Gamma Epsilon, an academic honor society for students of the Earth Sciences, is an important tradition at GSA annual meetings. Sigma Gamma Epsilon's goal in sponsoring this session is to provide a student-friendly forum for young researchers to present on undergraduate research; this session has seen increasing interest and participation over the years. The session is open to students (regardless of membership in Sigma Gamma Epsilon) and faculty co-authors working in any area of the geosciences. Those posters authored by student members in good standing of active chapters of Sigma Gamma Epsilon will be judged for two (2) …
Hip Extensor Mechanics And The Evolution Of Walking And Climbing Capabilities In Humans, Apes, And Fossil Hominins, Elaine E. Kozma, Nicole M. Webb, William Harcourt-Smith, David A. Raichlen, Kristiaan D’Août, Mary H. Brown, Emma M. Finestone, Stephen R. Ross, Peter Aerts, Herman Pontzer
Hip Extensor Mechanics And The Evolution Of Walking And Climbing Capabilities In Humans, Apes, And Fossil Hominins, Elaine E. Kozma, Nicole M. Webb, William Harcourt-Smith, David A. Raichlen, Kristiaan D’Août, Mary H. Brown, Emma M. Finestone, Stephen R. Ross, Peter Aerts, Herman Pontzer
Publications and Research
The evolutionary emergence of humans’ remarkably economical walking gait remains a focus of research and debate, but experi- mentally validated approaches linking locomotor capability to postcranial anatomy are limited. In this study, we integrated 3D morphometrics of hominoid pelvic shape with experimental mea- surements of hip kinematics and kinetics during walking and climbing, hamstring activity, and passive range of hip extension in humans, apes, and other primates to assess arboreal–terrestrial trade-offs in ischium morphology among living taxa. We show that hamstring-powered hip extension during habitual walking and climbing in living apes and humans is strongly predicted, and likely constrained, by …
Flow And Transport In Low-Gradient Rivers And Estuaries, Hunter Lee Clasen
Flow And Transport In Low-Gradient Rivers And Estuaries, Hunter Lee Clasen
USF Tampa Graduate Theses and Dissertations
For this dissertation I studied flow and transport in low gradient Florida streams. Chapter 2 is a statewide analysis of long-term variations in stream discharge. The results from Chapter 2 suggest that changes in mean annual stream discharge are controlled by the Atlantic Multi-Decadal Oscillation (AMO). During the warm phase, mean annual discharge decreases in central Florida and increases in north Florida. The opposite is true during the cool phase, with mean annual discharge increasing in central Florida and decreasing in north Florida. This pattern is observed for both components of stream discharge, base flow and runoff.
The following two …
Iodine To Calcium Ratios In Marine Carbonates As An Indicator Of Oxygen Levels, Angela Stahl
Iodine To Calcium Ratios In Marine Carbonates As An Indicator Of Oxygen Levels, Angela Stahl
Senior Honors Projects
ANGELA STAHL (Marine Biology)
Iodine to Calcium Ratios in Marine Carbonates as an Indicator of Oxygen Levels
Sponsor: Rebecca Robinson (Graduate School of Oceanography)
The Earth goes through natural cycles of warm and cool periods. In the past,
warmer oceans during interglacial periods have been shown to hold less oxygen
in their waters compared to cooler, glacial oceans. For this research, we are
studying an area in the Eastern Tropical Pacific where it is known to have
variable concentrations of dissolved oxygen in the waters due to the influence of
the climate. Oxygen is a vital component for most organisms …
Carbon Flux And Weathering Processes In Icelandic Glacial-Fed Rivers, Allison Quiroga
Carbon Flux And Weathering Processes In Icelandic Glacial-Fed Rivers, Allison Quiroga
Masters Theses & Specialist Projects
An investigation into the carbon dynamics and weathering processes occurring in Icelandic glacial-fed streams was conducted during the spring to summer seasonal transition in June of 2017. Four major outlet rives were sampled from the glaciers of Gígjökull, Steinsholtsjökull, Sólheimajökull, and Falljökull. Markarfljót, the major river that Gígjökull, Steinsholtsjökull, and many other glaciers drain into, was also sampled. Longitudinal sampling occurred at all sites to capture downstream trends in the hydrogeochemistry and carbon dynamics. Distinct differences in geochemistry between glacier surface meltwater, sub-glacial waters, pro-glacial lake water, and post-mixed downstream samples were evident in the data. Glacier surface streams were …
Primary Atmospheric Drivers Of Pluvial Years In The United States Great Plains, Paul Flanagan, Jeffrey B. Basara, Jason C. Furtado, Xiangming Xiao
Primary Atmospheric Drivers Of Pluvial Years In The United States Great Plains, Paul Flanagan, Jeffrey B. Basara, Jason C. Furtado, Xiangming Xiao
High Plains Regional Climate Center: Staff Publications
Precipitation variability has increased in recent decades across the Great Plains (GP) of the United States. Drought and its associated drivers have been studied in the GP region; however, periods of excessive precipitation (pluvials) at seasonal to interannual scales have received less attention. This study narrows this knowledge gap with the overall goal of understanding GP precipitation variability during pluvial periods. Through composites of relevant atmospheric variables from the ECMWF twentieth-century reanalysis (ERA-20C), key differences between southern Great Plains (SGP) and northern Great Plains (NGP) pluvial periods are highlighted. The SGP pluvial pattern shows an area of negative height anomalies …
Selection Perception: Views On The Theory Of Evolution Among Residents Of Moshi, Tanzania, Robin Waterman
Selection Perception: Views On The Theory Of Evolution Among Residents Of Moshi, Tanzania, Robin Waterman
Independent Study Project (ISP) Collection
The theory of evolution is a major tenet of biological science and has many practical applications, particularly in agriculture, medicine, and conservation. Nevertheless, there is significant opposition to the theory and its incorporation into school curricula, largely on religious grounds. This disconnect between public opinion and scientific opinion has been studied at length in the US and to some extent in other industrialized nations, but little is known about the issue in other communities around the world. This paper will use the town of Moshi, Tanzania as a case study in community views and knowledge about the theory of evolution. …
Revising The Geological Time Scale: A Conop9 Graptolite Composite From The Middle Ordovician Rocks Of Newfoundland, Katherine Michel
Revising The Geological Time Scale: A Conop9 Graptolite Composite From The Middle Ordovician Rocks Of Newfoundland, Katherine Michel
Honors Theses
The Geological Time Scale is a fundamental tool for geoscientists that is revised and republished every eight years. It is a representation of the geologic record - a system composed of radioisotope dates interpolated into fossil successions that can be used to correlate rocks. The current Geologic Time Scale for the Ordovician Period (GTS 2012) is composed of a sequence of species ranges from a group of fossils called graptolites with interpolated radiometric dates. Building a global geologic time scale requires correlating between different biofacies.
In this thesis I will attempt to combine stratigraphic range data from different kinds of …
Biogeochemical Cycling Of Selenium In The Arctic Ocean, Kyle M. Mcquiggan
Biogeochemical Cycling Of Selenium In The Arctic Ocean, Kyle M. Mcquiggan
OES Theses and Dissertations
Changes in the global climate may have a pronounced effect on the biogeochemical cycling of trace elements like selenium (Se) in the Arctic Ocean. This study described the first quantitative examination of the biogeochemical cycle of selenium in the Amerasian Basin, providing the baseline from which future changes can be identified. Aerosol, dissolved and particulate water samples were collected for Se determinations during the U.S. GEOTRACES GN01 Arctic expedition that sampled the two parts of the Amerasian Basin in 2015: The Makarov Basin on the way to the North Pole and the Canada Basin on the return trip to Dutch …
Mesoscale Effects On Carbon Export: A Global Perspective, Cheryl S. Harrison, Matthew C. Long, Nicole S. Lovenduski, Jefferson K. Moore
Mesoscale Effects On Carbon Export: A Global Perspective, Cheryl S. Harrison, Matthew C. Long, Nicole S. Lovenduski, Jefferson K. Moore
School of Earth, Environmental, & Marine Sciences Faculty Publications
Carbon export from the surface to the deep ocean is a primary control on global carbon budgets and is mediated by plankton that are sensitive to physical forcing. Earth system models generally do not resolve ocean mesoscale circulation ((10–100) km), scales that strongly affect transport of nutrients and plankton. The role of mesoscale circulation in modulating export is evaluated by comparing global ocean simulations conducted at 1∘ and 0.1∘ horizontal resolution. Mesoscale resolution produces a small reduction in globally integrated export production (<2%); however, the impact on local export production can be large (±50%), with compensating effects in different ocean basins. With mesoscale resolution, improved representation of coastal jets block off-shelf transport, leading to lower export in regions where shelf-derived nutrients fuel production. Export is further reduced in these regions by resolution of mesoscale turbulence, which restricts the spatial area of production. Maximum mixed layer depths are narrower and deeper across the Subantarctic at higher resolution, driving locally stronger nutrient entrainment and enhanced summer export production. In energetic regions with seasonal blooms, such as the Subantarctic and North Pacific, internally generated mesoscale variability drives substantial interannual variation in local export production. These results suggest that biogeochemical tracer dynamics show different sensitivities to transport biases than temperature and salinity, which should be considered in the formulation and validation of physical parameterizations. Efforts to compare estimates of export production from observations and models should account for large variability in space and time expected for regions strongly affected by mesoscale circulation.
Lithofaces And Sequence Architecture Of The Upper Paradox Formation (Middle Pennsylvanian)In The Subsurface Northern Blanding Subbasin, Paradox Basin, Utah, Geoffrey William Ritter
Lithofaces And Sequence Architecture Of The Upper Paradox Formation (Middle Pennsylvanian)In The Subsurface Northern Blanding Subbasin, Paradox Basin, Utah, Geoffrey William Ritter
Theses and Dissertations
THE PARADOX Basin is a northwest-southeast trending intracratonic basin that formedin southwestern Colorado, southeastern Utah and adjacent parts of Arizona and New Mexicoduring the late Paleozoic Era. During rise of the adjacent Uncompahgre Uplift (Ancestral RockyMountains) the rapidly subsiding basin was filled with over 2000 m of Permo-Pennsylvaniansediments. Stacked depositional sequences accumulated in three roughly parallel facies belts: anortheastern clastic belt (adjacent to uplift), a central salt and black shale belt, and asouthwestern carbonate belt. Over 400 million barrels of oil have been extracted from upperParadox (Desert Creek and Ismay) carbonates in the southern Blanding Subbasin (Greater AnethField) since 1956. …
Interactive Effects Of Hypoxia And Pcb Co-Exposure On Expression Of Cyp1a And Its Potential Regulators In Atlantic Croaker Liver, Md. Saydur Rahman, Peter Thomas
Interactive Effects Of Hypoxia And Pcb Co-Exposure On Expression Of Cyp1a And Its Potential Regulators In Atlantic Croaker Liver, Md. Saydur Rahman, Peter Thomas
School of Earth, Environmental, & Marine Sciences Faculty Publications
Although marine and coastal environments which are contaminated with xenobiotic organic compounds often become hypoxic during the summer, the interactive effects of hypoxia and xenobiotic exposure on marine species such as teleost fishes remain poorly understood. The expression and activity of monooxygenase enzyme cytochrome P450-1A (CYP1A) in fishes are upregulated by exposure to polychlorinated biphenyls (PCBs), whereas they are down-regulated during hypoxia exposure. We investigated the interactive effects of hypoxia and PCB co-exposure on hepatic CYP1A expression in Atlantic croaker and on potential regulators of CYP1A. Croaker were exposed to hypoxia (1.7 mg/L dissolved oxygen), 3,3′,4,4′-tetrachlorobiphenyl (PCB 77, dose: 2 …
Herbivory And Eutrophication Mediate Grassland Plant Nutrient Responses Across A Global Climatic Gradient, T. Michael Anderson, Daniel M. Griffith, James B. Grace, Eric M. Lind, Peter B. Adler, Lori A. Biederman, Dana M. Blumenthal, Pedro Daleo, Jennifer Firn, Nicole Hagenah, W. Stanley Harpole, Andrew S. Macdougall, Rebecca L. Mcculley, Suzanne M. Prober, Anita C. Risch, Mahesh Sankaran, Martin Schütz, Eric W. Seabloom, Carly J. Stevens, Lauren L. Sullivan, Peter D. Wragg, Elizabeth T. Borer
Herbivory And Eutrophication Mediate Grassland Plant Nutrient Responses Across A Global Climatic Gradient, T. Michael Anderson, Daniel M. Griffith, James B. Grace, Eric M. Lind, Peter B. Adler, Lori A. Biederman, Dana M. Blumenthal, Pedro Daleo, Jennifer Firn, Nicole Hagenah, W. Stanley Harpole, Andrew S. Macdougall, Rebecca L. Mcculley, Suzanne M. Prober, Anita C. Risch, Mahesh Sankaran, Martin Schütz, Eric W. Seabloom, Carly J. Stevens, Lauren L. Sullivan, Peter D. Wragg, Elizabeth T. Borer
Plant and Soil Sciences Faculty Publications
Plant stoichiometry, the relative concentration of elements, is a key regulator of ecosystem functioning and is also being altered by human activities. In this paper we sought to understand the global drivers of plant stoichiometry and compare the relative contribution of climatic vs. anthropogenic effects. We addressed this goal by measuring plant elemental (C, N, P and K) responses to eutrophication and vertebrate herbivore exclusion at eighteen sites on six continents. Across sites, climate and atmospheric N deposition emerged as strong predictors of plot‐level tissue nutrients, mediated by biomass and plant chemistry. Within sites, fertilization increased total plant nutrient pools, …
Assessing Phytoplankton Nutritional Status And Potential Impact Of Wet Deposition In Seasonally Oligotrophic Waters Of The Mid-Atlantic Bight, P. N. Sedwick, P. W. Bernhardt, M. R. Mulholland, R. G. Najjar, L. M. Blumen, B. M. Sohst, C. Sookhdeo, Brittany Widner
Assessing Phytoplankton Nutritional Status And Potential Impact Of Wet Deposition In Seasonally Oligotrophic Waters Of The Mid-Atlantic Bight, P. N. Sedwick, P. W. Bernhardt, M. R. Mulholland, R. G. Najjar, L. M. Blumen, B. M. Sohst, C. Sookhdeo, Brittany Widner
OES Faculty Publications
To assess phytoplankton nutritional status in seasonally oligotrophic waters of the southern Mid-Atlantic Bight, and the potential for rain to stimulate primary production in this region during summer, shipboard bioassay experiments were performed using natural seawater and phytoplankton collected north and south of the Gulf Stream. Bioassay treatments comprised iron, nitrate, iron + nitrate, iron + nitrate + phosphate, and rainwater. Phytoplankton growth was inferred from changes in chlorophyll a, inorganic nitrogen, and carbon-13 uptake, relative to unamended control treatments. Results indicated the greatest growth stimulation by iron + nitrate + phosphate, intermediate growth stimulation by rainwater, modest growth …