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2018

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Full-Text Articles in Earth Sciences

Carbon Flux And Weathering Processes In Icelandic Glacial-Fed Rivers, Allison Quiroga Apr 2018

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 Apr 2018

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 …


Evaluating The Applicability Of Modflow2005 Plus Mt3d-Usgs: Borden Case Study, Linley Mescher Apr 2018

Evaluating The Applicability Of Modflow2005 Plus Mt3d-Usgs: Borden Case Study, Linley Mescher

Civil and Environmental Engineering Master's Project Reports

Groundwater is essential to communities around the world for drinking, industrial, and agricultural purposes. MODFLOW is a modeling program that uses the three-dimensional continuity equation in a finite difference approach to simulate groundwater flow in an aquifer. MT3D-USGS is a MODFLOW package that simulates contaminant transport. This study used MODFLOW2005 with MT3D-USGS to build a model simulating contaminant transport in Borden, Ontario. A study conducted at the Borden site in 1982 injected a solution of eight solutes to test the transport of contaminants over three years. Initial simulations showed similar transport characteristics for chloride and carbon tetrachloride as compared to …


Daugherty Water For Food Global Institute Strategic Plan Fy18 – Fy23 Apr 2018

Daugherty Water For Food Global Institute Strategic Plan Fy18 – Fy23

Daugherty Water for Food Global Institute: Administrative Materials

Through research and policy development, education and communication, the institute is enhancing knowledge, fostering future water and food security leaders and developing effective techniques to sustainably manage water and increase food security. DWFI focuses its efforts in five areas of expertise and has identified key outcomes in each area to drive impact and measure success in the next five years, FY2018 to FY2023:

Closing Water & Agricultural Productivity Gaps: • Develop and deploy global satellite-based decision support and monitoring tools based on daily evapotranspiration estimates in key agricultural areas in the US and selected countries. • Improve knowledge of best …


Investigation On Relationships Between Optical Properties And Cell Concentrations Of Microalgae, Zhaoming Zhou Apr 2018

Investigation On Relationships Between Optical Properties And Cell Concentrations Of Microalgae, Zhaoming Zhou

Graduate Theses & Non-Theses

Biofuel from microalgae is a very promising renewable energy resource. Growth of microalgae depends on ambient temperature, appropriate nutrients in water, and light condition for photosynthesis. As microalgae grow, the depth of light penetration decreases and the growing conditions at depth deteriorate. Monitoring of microalgae concentration during their growing phase is imperative to ensure efficiency in biomass production. Conventionally, cell concentration (number of cells per unit volume) of microalgae solution is estimated by taking images of samples under microscope and then counted and estimated using the Metallized Hemacytometer Hausser Bright-Linewe (MHHBL) method developed by Hausser Scientific. This method of measuring …


Uav-Based Geotechnical Modeling And Mapping Of An Inaccessible Underground Site, Elizabeth Anne Russell Apr 2018

Uav-Based Geotechnical Modeling And Mapping Of An Inaccessible Underground Site, Elizabeth Anne Russell

Graduate Theses & Non-Theses

Digital photogrammetry is becoming a more common method used for mapping geological and structural rock mass features in underground mining. The issue of capturing geological and structural data in inaccessible, unsupported areas of mines remains even when utilizing terrestrial photogrammetric methods; thus, geotechnical models of mines are left with incomplete datasets. Large unsupported underground voids, like stopes, have the potential to cause major failures, but by filling in the geotechnical data gaps in inaccessible areas, potential failures can be predicted through kinematic analysis of the area’s mapped discontinuities. Implementation of Unmanned Aerial Vehicles (UAVs) in underground mines and recent advances …


Droughtscape, Spring 2018, National Drought Mitigation Center Apr 2018

Droughtscape, Spring 2018, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

Drought shifts to south in beginning of 2018

Ag records impacts; strong fire season forecast

Drought maps show regional and river forecast areas

Greenness indicator could save lives in Africa

NDMC on a global playing field

Visitors from Korea tap drought resources, experts

Svoboda named to United Nations advisory group

Responding to drought in the Southern Plains

Crops, cattle and climatology in the Upper Niobrara

Connecting locally for global change


Craters Of The Moon National Monument Basalts As Unshocked Compositional And Weathering Analogs For Martian Rocks And Meteorites, Christopher T. Adcock, Arya Udry, Elisabeth M. Hausrath, Oliver Tschauner Apr 2018

Craters Of The Moon National Monument Basalts As Unshocked Compositional And Weathering Analogs For Martian Rocks And Meteorites, Christopher T. Adcock, Arya Udry, Elisabeth M. Hausrath, Oliver Tschauner

Geoscience Faculty Research

The availability of terrestrial sites that are martian analogs allows researchers to investigate Mars using knowledge gained on Earth. Among the terrestrial analog sites for Mars is Craters of the Moon National Monument (COTM) in Idaho, U.S.A. Craters of the Moon National Monument is home to over 60 basalt lava flows, many of which have been dated from 2050 to 18 340 years before present (y.b.p.). Following previous authors, we examined the chemistry and petrogenesis of COTM basalts compared to basaltic martian rocks, martian meteorites, and meteorite clasts, and then examined the results of chemical weathering of the basaltic flows. …


Estimation Of Consistent Global Microwave Land Surface Emissivity From Amsr-E And Amsr2 Observations, Satya Prakash, Hamidreza Norouzi, Marzi Azarderakhsh, Reginald Blake, Catherine Prigent, Reza Khanbilvardi Apr 2018

Estimation Of Consistent Global Microwave Land Surface Emissivity From Amsr-E And Amsr2 Observations, Satya Prakash, Hamidreza Norouzi, Marzi Azarderakhsh, Reginald Blake, Catherine Prigent, Reza Khanbilvardi

Publications and Research

Accurate estimation of passive microwave land surface emissivity (LSE) is crucial for numerical weather prediction model data assimilation, for microwave retrievals of land precipitation and atmospheric profiles, and for better understanding of land surface and sub-surface characteristics. In this study, global instantaneous LSE is estimated for the 9-year period from the Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E) and for the 5-year period from the Advanced Microwave Scanning Radiometer - 2 (AMSR2) sensors. Estimates of LSE from both sensors were obtained by using an updated algorithm that minimizes the discrepancy between the differences in penetration depths from microwave …


Bridging The Under-Five Mortality Gap For Africa In The Era Of Sustainable Development Goals: An Ordinary Least Squares (Ols) Analysis, Michael Acheampong, Chukwudi Ejiofor, Abraham A. Salinas-Miranda, Foday M. Jaward, Michael K. Eduful, Qiuyan Yu Apr 2018

Bridging The Under-Five Mortality Gap For Africa In The Era Of Sustainable Development Goals: An Ordinary Least Squares (Ols) Analysis, Michael Acheampong, Chukwudi Ejiofor, Abraham A. Salinas-Miranda, Foday M. Jaward, Michael K. Eduful, Qiuyan Yu

School of Geosciences Faculty and Staff Publications

Background: While Africa achieved significant progress in reducing under-five mortality rate (U5MR) in the MDGs era, it did not achieve the set target and still has the highest average of 81 deaths per 1000 live births compared to a global average of 43 deaths. The SDG number 3 has set a new target of reducing U5MR to 25 deaths per 1000 births in the world, which serves a huge challenge, especially for Africa. Socioeconomic inequities that remain unaddressed across countries account for Africa’s high U5MR. Unless there is adequate prioritization of important socioeconomic, healthcare, and environmental factors, the new SDGs …


Grounding Line Migration Through The Calving Season At Jakobshavn Isbræ, Greenland, Observed With Terrestrial Radar Interferometry, Surui Xie, Timothy H. Dixon, Denis Voytenko, Fanghui Deng, David M. Holland Apr 2018

Grounding Line Migration Through The Calving Season At Jakobshavn Isbræ, Greenland, Observed With Terrestrial Radar Interferometry, Surui Xie, Timothy H. Dixon, Denis Voytenko, Fanghui Deng, David M. Holland

School of Geosciences Faculty and Staff Publications

Ice velocity variations near the terminus of Jakobshavn Isbræ, Greenland, were observed with a terrestrial radar interferometer (TRI) during three summer campaigns in 2012, 2015, and 2016. We estimate a  ∼ 1km wide floating zone near the calving front in early summer of 2015 and 2016, where ice moves in phase with ocean tides. Digital elevation models (DEMs) generated by the TRI show that the glacier front here was much thinner (within 1km of the glacier front, average ice surface is  ∼ 100 and  ∼ 110m above local sea level in 2015 and 2016, respectively) than ice upstream (average ice …


Investigating The Origin Of Continual Radio Frequency Impulses During Explosive Volcanic Eruptions, S. A. Behnke, H. E. Edens, R. J. Thomas, C. M. Smith, Stephen R. Mcnutt, A. R. Van Eaton, C. Cimarelli, V. Cigala Apr 2018

Investigating The Origin Of Continual Radio Frequency Impulses During Explosive Volcanic Eruptions, S. A. Behnke, H. E. Edens, R. J. Thomas, C. M. Smith, Stephen R. Mcnutt, A. R. Van Eaton, C. Cimarelli, V. Cigala

School of Geosciences Faculty and Staff Publications

Volcanic lightning studies have revealed that there is a relatively long‐lasting source of very high frequency radiation associated with the onset of explosive volcanic eruptions that is distinct from radiation produced by lightning. This very high frequency signal is referred to as “continual radio frequency (CRF)” due to its long‐lasting nature. The discharge mechanism producing this signal was previously hypothesized to be caused by numerous, small (10–100 m) leader‐forming discharges near the vent of the volcano. To test this hypothesis, a multiparametric data set of electrical and volcanic activity occurring during explosive eruptions of Sakurajima Volcano in Japan was collected …


Production And Composition Of Pyrogenic Dissolved Organic Matter From A Logical Series Of Laboratory-Generated Chars, Kyle W. Bostick, Andrew R. Zimmerman, Andrew S. Wozniak, Siddhartha Mitra, Patrick G. Hatcher Apr 2018

Production And Composition Of Pyrogenic Dissolved Organic Matter From A Logical Series Of Laboratory-Generated Chars, Kyle W. Bostick, Andrew R. Zimmerman, Andrew S. Wozniak, Siddhartha Mitra, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Though pyrogenic carbon (pyC) has been assumed to be predominantly stable, degradation and transfers of pyC between various pools have been found to influence its cycling and longevity in the environment. Dissolution via leaching may be the main control on loss processes such as microbial or abiotic oxidation, mineral sorption, or export to aquatic systems. Yet, little is known about the controls on pyrogenic dissolved organic matter (pyDOM) generation or composition. Here, the yield and composition of pyDOM generated through batch leaching of a thermal series of oak and grass biochars, as well as several non-pyrogenic reference materials, was compared …


Climate Change And The Global Pattern Of Moraine-Dammed Glacial Lake Outburst Floods, Stephan Harrison, Jeffrey S. Kargel, Christian Huggel, John Reynolds, Dan H. Shugar, Richard A. Betts, Neil Glasser, Umesh K. Haritashya, Jan Klimeš, Liam Reinhardt, Yvonne Schaub, Andy Wiltshire, Dhananjay Regmi, Vít Vilímek Apr 2018

Climate Change And The Global Pattern Of Moraine-Dammed Glacial Lake Outburst Floods, Stephan Harrison, Jeffrey S. Kargel, Christian Huggel, John Reynolds, Dan H. Shugar, Richard A. Betts, Neil Glasser, Umesh K. Haritashya, Jan Klimeš, Liam Reinhardt, Yvonne Schaub, Andy Wiltshire, Dhananjay Regmi, Vít Vilímek

Department of Earth, Environment and Sustainability Faculty Publications

Despite recent research identifying a clear anthropogenic impact on glacier recession, the effect of recent climate change on glacier-related hazards is at present unclear. Here we present the first global spatio-temporal assessment of glacial lake outburst floods (GLOFs) focusing explicitly on lake drainage following moraine dam failure. These floods occur as mountain glaciers recede and downwaste. GLOFs can have an enormous impact on downstream communities and infrastructure. Our assessment of GLOFs associated with the rapid drainage of moraine-dammed lakes provides insights into the historical trends of GLOFs and their distributions under current and future global climate change. We observe a …


Mapping And Interpreting The Glacial Geology Of Pictured Rocks National Lakeshore, Michigan, Sarah M. Vandermeer Apr 2018

Mapping And Interpreting The Glacial Geology Of Pictured Rocks National Lakeshore, Michigan, Sarah M. Vandermeer

Dissertations

Pictured Rocks National Lakeshore is among the most popular parks in Michigan, yet prior to this study, it was the only National Park that lacked a detailed surficial geology map characterizing the distribution of sediments and landforms. Additionally, much of the landscape remained unexplored. These factors prevented thorough interpretations of landscape development and evolution. This research aims to map and further explore the relationship of glacial sediments and landforms throughout Pictured Rocks to refine and expand the current understanding of glacial events that shaped this landscape.

A new, detailed (1:24,000-scale) surficial geology map of the ten 7.5-minute quadrangles that contain …


A Geomorphological Study Of Yardangs In China, The Altiplano/Puna Of Argentina, And Iran As Analogs For Yardangs On Titan, Dustin Shawn Northrup Apr 2018

A Geomorphological Study Of Yardangs In China, The Altiplano/Puna Of Argentina, And Iran As Analogs For Yardangs On Titan, Dustin Shawn Northrup

Theses and Dissertations

Collections of straight, RADAR-bright, linear features, or BLFs, on Saturn's moon Titan are revealed in Cassini SAR (Synthetic Aperture RADAR) images. Most are widely distributed across the northern midlatitudes SAR on SAR swaths T18, T23, T30, T64, and T83 and in swath T56 in the southern midlatitudes. To understand the origin of these features, we compare them with terrestrial yardangs in Dunhuang, China, the Altiplano/Puna of Argentina, and the Lut Desert of Iran and with a similar morphological landform, linear dunes in the Namib Sand Sea, Namibia and on Titan. We apply a statistical classification model developed through random forests, …


A Geophysical And Geological Analysis Of A Regressive-Phase Lake Bonneville Deposit, Pilot Valley, Nv, Katelynn Marie Smith Apr 2018

A Geophysical And Geological Analysis Of A Regressive-Phase Lake Bonneville Deposit, Pilot Valley, Nv, Katelynn Marie Smith

Theses and Dissertations

Pilot Valley, located in the eastern Basin and Range, north of Wendover, UT, contains numerous shorelines and depositional remnants of late Pleistocene Lake Bonneville. These remnants present classic ground penetrating radar (GPR) targets due to their coherent stratification, low clay, low salinity, and low moisture content. Three-dimensional (3D) GPR imaging can resolve fine-scale stratigraphy of these deposits down to a few centimeters. While lake levels fluctuated due to flooding events, climatic changes were the dominant factor in controlling lake levels. In Pilot Valley, the paleowind entered from the northwest, with storms coming from the south, and circulated clockwise around the …


Earth News, V41, Spring 2018, University Of Northern Iowa. Department Of Earth And Environmental Sciences. Apr 2018

Earth News, V41, Spring 2018, University Of Northern Iowa. Department Of Earth And Environmental Sciences.

Earth News

Inside this issue:
-- From the Department Head
-- Faculty Updates
-- SGE Newsletter
-- Student Awards
-- Sunday at the Quarry
-- Alumni Spotlight
-- A Unique Honor
-- In Memorium
-- Lake Michigan Ozone Study
-- Student Research
-- Hydrology News
-- Carver Grants
-- 2017-2018 Pictures
-- Alumni-in-Residence
-- Alumni Updates
-- Solar Eclipse Party
-- How Many Snowflakes
-- Geology and Interior Design
-- Beta Project
-- Stem Story
-- Gifts From Alumni & Friends
-- Contribution Form


Revising The Geological Time Scale: A Conop9 Graptolite Composite From The Middle Ordovician Rocks Of Newfoundland, Katherine Michel Apr 2018

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 …


Iodine To Calcium Ratios In Marine Carbonates As An Indicator Of Oxygen Levels, Angela Stahl Apr 2018

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 …


Biogeochemical Cycling Of Selenium In The Arctic Ocean, Kyle M. Mcquiggan Apr 2018

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 …


Lithofaces And Sequence Architecture Of The Upper Paradox Formation (Middle Pennsylvanian)In The Subsurface Northern Blanding Subbasin, Paradox Basin, Utah, Geoffrey William Ritter Apr 2018

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. …


Selection Perception: Views On The Theory Of Evolution Among Residents Of Moshi, Tanzania, Robin Waterman Apr 2018

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. …


Cuando La Vida Era Tranquila: Land Use And Livelihood Changes Following The Construction Of The Chan 75 Dam In Nance Del Risco, Bocas Del Toro, Patrick Mckenzie Apr 2018

Cuando La Vida Era Tranquila: Land Use And Livelihood Changes Following The Construction Of The Chan 75 Dam In Nance Del Risco, Bocas Del Toro, Patrick Mckenzie

Independent Study Project (ISP) Collection

The Ngobe are Panama’s most populous indigenous group. While the Ngobe that live in the comarca have land and resource rights, those that live immediately outside of it do not. This issue has been exacerbated by the creation of Palo Seco Forest Reserve which has removed all land rights from the Ngobe living within it. In order to meet its growing demand for energy, Panama is expanding its hydroelectric sector. One such hydroelectric dam built by AES is Chan 75. However, Chan 75 has had a controversial history, especially regarding its treatment of the Ngobe people of the corregimiento Nance …


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 Apr 2018

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, …


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 Apr 2018

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 …


Improving The Total Organic Carbon Estimation Of The Eagle Ford Shale With Density Logs By Considering The Effect Of Pyrite, Shuxian Jiang, Mehdi Mokhtari, David M. Borrok, Jim Lee Apr 2018

Improving The Total Organic Carbon Estimation Of The Eagle Ford Shale With Density Logs By Considering The Effect Of Pyrite, Shuxian Jiang, Mehdi Mokhtari, David M. Borrok, Jim Lee

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Pyrite is a common mineral with a higher density than most other minerals in the Eagle Ford Shale formation. Hence, if pyrite is not considered in the total organic carbon (TOC) estimation, based on density logs, it may lead to errors. In order to improve the accuracy of the TOC estimation, we propose an updated TOC estimation method that incorporates the concentration of pyrite and organic porosity. More than 15 m of Eagle Ford Shale samples were analyzed using Rock-Eval pyrolysis, X-ray fluorescence (XRF), and X-ray diffraction (XRD). TOC, elemental concentration, and mineralogical data were analyzed for a better understanding …


The Concept Of Water Storage On Agriculture Lands: Exploring The Notion In South Florida, Kayla Ouellette, Kamal Alsharif, John C. Capece, Hannah Torres Apr 2018

The Concept Of Water Storage On Agriculture Lands: Exploring The Notion In South Florida, Kayla Ouellette, Kamal Alsharif, John C. Capece, Hannah Torres

School of Geosciences Faculty and Staff Publications

Lands in the Everglades Agricultural Area (EAA) can be used for increased water storage in order to relieve coastal estuaries of excess runoff in the rainy season. The goals of this study were: (1) to quantify the environmental and economic tradeoffs of different water storage scenarios using water tolerant sugarcane cultivars; and (2) to quantify the amount of water storage possible in the EAA under different water storage scenarios. A mathematical model was developed to calculate soil depth, soil subsidence, depth to the water table, and water storage for three different sugarcane cultivars with different water tolerances. The …


Predicting Effects Of Climate Change And Sea Level Rise On Hydrologic Processes In A Mid-Atlantic Coastal Watershed, Rui Li Apr 2018

Predicting Effects Of Climate Change And Sea Level Rise On Hydrologic Processes In A Mid-Atlantic Coastal Watershed, Rui Li

Civil & Environmental Engineering Theses & Dissertations

This dissertation assessed impacts of Climate Change (CC) and Sea Level Rise (SLR) on coastal hydrologic processes using the Lynnhaven River watershed as a test bed. The watershed is part of Chesapeake Bay Watershed and hydraulically connected with mid-Atlantic Ocean. Six CC scenarios were considered in terms of eight Regional Climate Models’ predictions for three Intergovernmental Panel on Climate Change (IPCC) emission assumptions, namely, B1, A1B, and A2, for two future periods, namely 2046 to 2065 and 2081 to 2099. The ensemble means of downscaling results from four methods were used to represent the future climates. On the other hand, …


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 Apr 2018

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 …