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Articles 12751 - 12780 of 17799
Full-Text Articles in Entire DC Network
Hydrocarbon And Co2 Emissions From Oil And Gas Production Well Pad Soils Comparative To Background Soil Emissions In Eastern Utah, Cody S. Watkins
Hydrocarbon And Co2 Emissions From Oil And Gas Production Well Pad Soils Comparative To Background Soil Emissions In Eastern Utah, Cody S. Watkins
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
What effect does the development of oil and gas have on the observed air quality (i.e., increased ozone, carbon dioxide (CO2), volatile organic compounds (VOCs), and/or methane emissions) in northeastern Utah? What percentage of these gases is natural background emissions, and what percentage is due to the recent oil and gas development in the region? Emissions in this text refer to gases released from the earth’s surface to the atmosphere. Methane is the primary compound in natural gas. Natural gas is a naturally occurring hydrocarbon gas mixture. Emissions of methane, non-methane hydrocarbons (NMHC), and CO2 at 27 …
Sclerocactus Wetlandicus: Habitat Characterization, Seed Germination And Mycorrhizal Analysis, Kourtney T. Harding
Sclerocactus Wetlandicus: Habitat Characterization, Seed Germination And Mycorrhizal Analysis, Kourtney T. Harding
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Uinta Basin hookless cactus (Sclerocactus wetlandicus) is a threatened species native to Eastern Utah. The cactus is found in a landscape highly disturbed by non-renewable energy production. To understand the environmental conditions that support natural growth of this cactus, we asked what types of plants were present in the same areas as the cactus, and if the types of plants were different in environments that were disturbed. From our assessment, we determined that the types of plants present in disturbed areas were drastically different from those present in undisturbed locations. Areas previously used for energy production are …
Effect Of Foliage And Root Carbon Quantity, Quality, And Fluxes On Soil Organic Carbon Stabilization In Montane Aspen And Conifer Stands In Utah, Antra Boča
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Soil organic carbon (SOC) positively affects many soil properties (e.g., fertility and water holding capacity), and the amount of carbon (C) in soil exceeds the amount in the atmosphere by about three times. Forest soils store as much C as is found in trees. Tree species differ in their effect on SOC pools. Quaking aspen forests in the Western US often store more stable SOC in the mineral soil than nearby conifers. During the last decades a decline in aspen cover, often followed by conifer encroachment, has been documented. A shift from aspen to conifer overstories may negatively affect the …
A Stochastic Model For Water-Vegetation Systems And The Effect Of Decreasing Precipitation On Semi-Arid Environments, Shannon A. Dixon
A Stochastic Model For Water-Vegetation Systems And The Effect Of Decreasing Precipitation On Semi-Arid Environments, Shannon A. Dixon
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Current climate change trends are affecting the magnitude and recurrence of extreme weather events. In particular, several semi-arid regions around the planet are confronting more intense and prolonged lack of precipitation, slowly transforming these regions into deserts. Many mathematical models have been developed for purposes of analyzing vegetation-water interactions, particularly in semi-arid landscapes. Most models are based on the average behavior of the system as a whole, and how it is influenced by external changes. These models may be termed "macro-scale" models. Other models have concerned themselves with the interactions between individuals, in this case the interactions between individual plants …
Riparian Buffered Sinkholes In The Blue River Watershed, Colin Copler
Riparian Buffered Sinkholes In The Blue River Watershed, Colin Copler
Undergraduate Theses
Riparian vegetation along streams has many positive effects on water quality and macroinvertebrate communities, especially in agricultural areas. Some of these effects include erosion prevention, pollutant removal, and lower summer water temperatures. There has been much research done examining the link between these riparian areas and streams; however, riparian vegetation is understudied in karst areas. Karst is a geologic formation that is composed of limestone, which dissolves in groundwater, forming sinkholes. Thus, the question this paper seeks to investigate is does riparian vegetation around sinkholes in a karst plain influence water quality within a watershed? Water quality, land cover, and …
Sensitivity Of Mangrove Range Limits To Climate Variability, Kyle C. Cavanaugh, Michael J. Osland, Remi Bardou, Gustavo Hinojosa-Arango, Juan M. Lopez-Vivas, John D. Parker, Andre S. Rovai
Sensitivity Of Mangrove Range Limits To Climate Variability, Kyle C. Cavanaugh, Michael J. Osland, Remi Bardou, Gustavo Hinojosa-Arango, Juan M. Lopez-Vivas, John D. Parker, Andre S. Rovai
United States Geological Survey: Staff Publications
Aim: Correlative distribution models have been used to identify potential climatic controls of mangrove range limits, but there is still uncertainty about the relative importance of these factors across different regions. To provide insights into the strength of climatic control of different mangrove range limits, we tested whether temporal variability in mangrove abundance increases near range limits and whether this variability is correlated with climatic factors thought to control large scale mangrove distributions.
Location: North and South America.
Time period: 1984–2011.
Major taxa studied: Avicennia germinans, Avicennia schuaeriana, Rhizophora mangle, Laguncularia racemosa.
Methods: We characterized temporal variability in the enhanced …
Plant Diversity Influences The Structure And Function Of A Restored Prairie And Its Responses To Added Disturbances, Rebecca Bevans
Plant Diversity Influences The Structure And Function Of A Restored Prairie And Its Responses To Added Disturbances, Rebecca Bevans
School of Natural Resources: Dissertations, Theses, and Student Research
As global warming, human conversion of natural landscapes to agricultural uses, and widespread biodiversity losses continue to alter the ecosystems we depend on, an understanding of the relationship between ecosystem structure, composition, and function is needed to maintain valuable ecosystem states and their associated functions. Research testing the limits of an ecosystem’s ability to maintain essential structure and functioning under disturbance conditions can aid in this goal.
In this study, I measured the relationship between plant diversity, community structure and functional traits, and their responses to added disturbances. I added disturbances representing those either caused or intensified by human activity …
Mapping The Spatial-Temporal Variation In Ras Ghanada Seagrass Meadows And Sand Shoals Between 1996, 2006 & 2012, Ryan Brookbank
Mapping The Spatial-Temporal Variation In Ras Ghanada Seagrass Meadows And Sand Shoals Between 1996, 2006 & 2012, Ryan Brookbank
HCNSO Student Theses and Dissertations
Seagrass meadows offshore Ras Ghanada, as elsewhere, are an important component to the ecosystem providing numerous benefits to both aquatic and human life. This work focused on mapping the spatial and temporal distribution of seagrass meadows offshore Ras Ghanada using aerial photography acquired in 1996 and high-resolution satellite images captured in 2006 and 2012. The movements of sand shoals were also tracked, so as to further explain the dynamics of this ecosystem, as it is the area between the shoal crests that hosts the best developed seagrass meadows. The natural limiting factor for seagrass on the Ras Ghanada coastal shelf …
Draft Nuclear Genome Sequence Of The Liquid Hydrocarbon–Accumulating Green Microalga Botryococcus Braunii Race B (Showa), Daniel R. Browne, Jerry Jenkins, Jeremy Schmutz, Shengqiang Shu, Kerrie Barry, Jane Grimwood, Jennifer Chiniquy, Aditi Sharma, Thomas Daniel Niehaus, Taylor L. Weiss, Andrew T. Koppisch, David T. Fox, Suraj Dhungana, Shigeru Okada, Joe Chappell, Timothy P. Devarenne
Draft Nuclear Genome Sequence Of The Liquid Hydrocarbon–Accumulating Green Microalga Botryococcus Braunii Race B (Showa), Daniel R. Browne, Jerry Jenkins, Jeremy Schmutz, Shengqiang Shu, Kerrie Barry, Jane Grimwood, Jennifer Chiniquy, Aditi Sharma, Thomas Daniel Niehaus, Taylor L. Weiss, Andrew T. Koppisch, David T. Fox, Suraj Dhungana, Shigeru Okada, Joe Chappell, Timothy P. Devarenne
Plant and Soil Sciences Faculty Publications
Botryococcus braunii has long been known as a prodigious producer of liquid hydrocarbon oils that can be converted into combustion engine fuels. This draft genome for the B race of B. braunii will allow researchers to unravel important hydrocarbon biosynthetic pathways and identify possible regulatory networks controlling this unusual metabolism.
Δ13c And Δ15n In The Endangered Kemp’S Ridley Sea Turtle Lepidochelys Kempii After The Deepwater Horizon Oil Spill, Kimberly J. Reich, Melania C. López-Castro, Donna J. Shaver, Claire Iseton, Kristen M. Hart, Michael J. Hooper, Christopher J. Schmitt
Δ13c And Δ15n In The Endangered Kemp’S Ridley Sea Turtle Lepidochelys Kempii After The Deepwater Horizon Oil Spill, Kimberly J. Reich, Melania C. López-Castro, Donna J. Shaver, Claire Iseton, Kristen M. Hart, Michael J. Hooper, Christopher J. Schmitt
United States Geological Survey: Staff Publications
The Deepwater Horizon explosion in April 2010 and subsequent oil spill released 3.19 × 106 barrels (5.07 × 108 l) of MC252 crude oil into important foraging areas of the endangered Kemp’s ridley sea turtle Lepidochelys kempii (Lk) in the northern Gulf of Mexico (GoM). We measured δ13C and δ15N in scute biopsy samples from 33 Lk nesting in Texas during the period 2010 to 2012. Of these, 27 were equipped with satellite transmitters and were tracked to traditional foraging areas in the northern GoM after the spill. Differences in δ13C between the oldest and newest scute layers from 2010 …
Vegetation Response To Invasive Tamarix Control In Southwestern U.S. Rivers: A Collaborative Study Including 416 Sites, Eduardo Gonzalez, Anna A. Sher, Robert M. Anderson, Robin F. Bay, Daniel W. Bean, Gabriel J. Bissonnete, Berenger Bourgeois, David J. Cooper, Kara Dohrenwend, Kim D. Eichhorst, Hishma El Waer, Deborah K. Kennard, Rebecca Harms-Weissinger, Annie L. Henry, Lori J. Makarick, Steven M. Ostoja, Lindsay V. Reynolds, W. Wright Robinson, Patrick B. Shafroth
Vegetation Response To Invasive Tamarix Control In Southwestern U.S. Rivers: A Collaborative Study Including 416 Sites, Eduardo Gonzalez, Anna A. Sher, Robert M. Anderson, Robin F. Bay, Daniel W. Bean, Gabriel J. Bissonnete, Berenger Bourgeois, David J. Cooper, Kara Dohrenwend, Kim D. Eichhorst, Hishma El Waer, Deborah K. Kennard, Rebecca Harms-Weissinger, Annie L. Henry, Lori J. Makarick, Steven M. Ostoja, Lindsay V. Reynolds, W. Wright Robinson, Patrick B. Shafroth
United States Geological Survey: Staff Publications
Most studies assessing vegetation response following control of invasive Tamarix trees along southwestern U.S. rivers have been small in scale (e.g., river reach), or at a regional scale but with poor spatial-temporal replication, and most have not included testing the effects of a now widely used biological control. We monitored plant composition following Tamarix control along hydrologic, soil, and climatic gradients in 244 treated and 172 reference sites across six U.S. states. This represents the largest comprehensive assessment to date on the vegetation response to the four most common Tamarix control treatments. Biocontrol by a defoliating beetle (treatment 1) reduced …
Furman University Lake Restoration Project
Furman University Lake Restoration Project
Furman Lake Restoration Book Gallery
An overview of the Furman Lake Restoration Project. The overview includes photographs and charts. It provides information on the history of the Furman Lake, it's environmental health decline throughout the years, and the lake's restoration. The overview details the Furman Lake's problems, causes of these problems, and solutions. It describes Furman's progress in the restoration project, as well as it's goals for the future.
Catalyzed Synthesis Of Zinc Clays By Prebiotic Central Metabolites, Marcelo I. Guzman, Ruixin Zhou, Kaustuv Basu, Hyman Hartman, Christopher J. Matocha, S. Kelly Sears, Hajatollah Vali
Catalyzed Synthesis Of Zinc Clays By Prebiotic Central Metabolites, Marcelo I. Guzman, Ruixin Zhou, Kaustuv Basu, Hyman Hartman, Christopher J. Matocha, S. Kelly Sears, Hajatollah Vali
Chemistry Faculty Publications
How primordial metabolic networks such as the reverse tricarboxylic acid (rTCA) cycle and clay mineral catalysts coevolved remains a mystery in the puzzle to understand the origin of life. While prebiotic reactions from the rTCA cycle were accomplished via photochemistry on semiconductor minerals, the synthesis of clays was demonstrated at low temperature and ambient pressure catalyzed by oxalate. Herein, the crystallization of clay minerals is catalyzed by succinate, an example of a photoproduced intermediate from central metabolism. The experiments connect the synthesis of sauconite, a model for clay minerals, to prebiotic photochemistry. We report the temperature, pH, and concentration dependence …
Accelerated Increase In The Arctic Tropospheric Warming Events Surpassing Stratospheric Warming Events During Winter, Shih-Yu (Simon) Wang, Yen-Heng Lin, Ming-Ying Lee, Jin-Ho Yoon, Jonathan D.D. Meyer, Philip J. Rasch
Accelerated Increase In The Arctic Tropospheric Warming Events Surpassing Stratospheric Warming Events During Winter, Shih-Yu (Simon) Wang, Yen-Heng Lin, Ming-Ying Lee, Jin-Ho Yoon, Jonathan D.D. Meyer, Philip J. Rasch
Plants, Soils, and Climate Faculty Publications
In January 2016, a robust reversal of the Arctic Oscillation (AO) took place associated with a rapid tropospheric warming in the Arctic region; this was followed by the occurrence of a classic sudden stratospheric warming in March-April. The succession of these two distinct Arctic warming events provides a stimulating opportunity to examine their characteristics in terms of similarities and differences. Historical cases of these two types of Arctic warming were identified and validated based upon tropical linkages with the Madden-Julian Oscillation and El Niño as well as those documented in previous studies. Our results indicate a recent and accelerated increase …
Field-Scale Observations Of A Transient Geobattery Resulting From Natural Attenuation Of A Crude Oil Spill, Jeffrey W. Heenan, Dimitrios Ntarlagiannis, Lee D. Slater, Carol L. Beaver, Silvia Rossbach, Andre Revil, Estella A. Atekwana, Barbara A. Bekins
Field-Scale Observations Of A Transient Geobattery Resulting From Natural Attenuation Of A Crude Oil Spill, Jeffrey W. Heenan, Dimitrios Ntarlagiannis, Lee D. Slater, Carol L. Beaver, Silvia Rossbach, Andre Revil, Estella A. Atekwana, Barbara A. Bekins
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
We present evidence of a geobattery associated with microbial degradation of a mature crude oil spill. Self-potential measurements were collected using a vertical array of nonpolarizing electrodes, starting at the land surface and passing through the smear zone where seasonal water table fluctuations have resulted in the coating of hydrocarbons on the aquifer solids. These passive electrical potential measurements exhibit a dipolar pattern associated with a current source. The anodic and cathodic reactions of this natural battery occur below and above the smear zone, respectively. The smear zone is characterized by high magnetic susceptibility values associated with the precipitation of …
Synoptic Atmospheric Conditions, Land Cover, And Equivalent Temperature Variations In Kentucky, Dorothy Yemaa Na-Yemeh
Synoptic Atmospheric Conditions, Land Cover, And Equivalent Temperature Variations In Kentucky, Dorothy Yemaa Na-Yemeh
Masters Theses & Specialist Projects
Research has demonstrated that equivalent temperature (TE), which incorporates both the surface air temperature (T) and moist heat content associated with atmospheric moisture, is a better indicator of overall heat content. This thesis follows up on a study that used TE to determine the impacts of land use/land cover and air masses on the atmospheric heat content over Kentucky during the growing season (April-September). The study, which used data from the Kentucky Mesonet, reveals that moist weather types dominate the growing season and, as expected, differences between T and TE are smaller under dry atmospheric conditions …
Characterizing South American Mesoscale Convective Complexes Using Isotope Hydrology, Kyle J. Hogancamp
Characterizing South American Mesoscale Convective Complexes Using Isotope Hydrology, Kyle J. Hogancamp
Masters Theses & Specialist Projects
Mesoscale convective complexes (MCCs) over subtropical South America contribute an average annual volume of precipitation equal to approximately seven km3 and occur with an average regularity in the region, with more than 30 per warm season. Isotopic characteristics of precipitation, such as δ2H and δ18O values, provide information that can be used to identify unique processes and sources related to precipitation events. The largest database of isotope characteristics of precipitation within the region is the Global Network of Isotopes in Precipitation (GNIP), which provides varying temporal resolution data from stations around the world, including subtropical South America.
Using this database, …
Supergene Mineralization Of The Continental Pit, Butte, Silver Bow County, Montana, Kyle Eastman
Supergene Mineralization Of The Continental Pit, Butte, Silver Bow County, Montana, Kyle Eastman
Graduate Theses & Non-Theses
The Butte porphyry Cu-Mo-Ag deposit has been considerably altered by supergene processes that enriched Cu and Ag, and mobilized other metals. Supergene enrichment provided early miners with excellent ore grades, and contributes significantly to current mining operations in Butte. The Continental Pit exhibits the classic leached and enriched vertical zonation that is common in near-surface porphyry systems around the world. Although studied by the Anaconda Copper Mining Company during the mid-20th century, significant and economically relevant questions remain regarding this deposit’s supergene heavy metal geochemistry and its relationship to the local hydrology and tectonic history.
This thesis investigates the paragenesis …
Open Data And Digital Morphology, Thomas G. Davies, Imran A. Rahman, Stephan Lautenschlager, John A. Cunningham, Robert J. Asher, Paul M. Barrett, Karl T. Bates, Stefan Bengtson, Roger B. J. Benson, Doug M. Boyer, José Braga, Jen A. Bright
Open Data And Digital Morphology, Thomas G. Davies, Imran A. Rahman, Stephan Lautenschlager, John A. Cunningham, Robert J. Asher, Paul M. Barrett, Karl T. Bates, Stefan Bengtson, Roger B. J. Benson, Doug M. Boyer, José Braga, Jen A. Bright
School of Geosciences Faculty and Staff Publications
Over the past two decades, the development of methods for visualizing and analysing specimens digitally, in three and even four dimensions, has transformed the study of living and fossil organisms. However, the initial promise that the widespread application of such methods would facilitate access to the underlying digital data has not been fully achieved. The underlying datasets for many published studies are not readily or freely available, introducing a barrier to verification and reproducibility, and the reuse of data. There is no current agreement or policy on the amount and type of data that should be made available alongside studies …
Evaluating The Impacts Of Grassland Conversions To Experimental Forest On Groundwater Recharge In The Nebraska Sand Hills, Zablon A. Adane
Evaluating The Impacts Of Grassland Conversions To Experimental Forest On Groundwater Recharge In The Nebraska Sand Hills, Zablon A. Adane
Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research
The Nebraska Sand Hills grasslands provide the greatest groundwater recharge rates in the High Plains Aquifer. However, the grasslands and their ecological services have become vulnerable to land use change and degradation. This study used a series of field data to investigate the effects of grassland conversions to forest on recharge rates in a century-old experimental forest in the Sand Hills. The results show that the impact of grassland conversion on recharge was dependent on the species and plantation density. Estimated recharge rates beneath the dense plantations represent reductions of 86–94% relative to the native grassland. Results of 1H …
A Program Aimed Toward Inclusive Excellence For Underrepresented Undergraduate Women In The Sciences, Laura A. Katz, Kathryn M. Aloisio, Nicholas J. Horton, Minh Ly, Sara B. Pruss, Kate Queeney, Cate Rowen, Patricia Marten Dibartolo
A Program Aimed Toward Inclusive Excellence For Underrepresented Undergraduate Women In The Sciences, Laura A. Katz, Kathryn M. Aloisio, Nicholas J. Horton, Minh Ly, Sara B. Pruss, Kate Queeney, Cate Rowen, Patricia Marten Dibartolo
Biological Sciences: Faculty Publications
Created to foster inclusive excellence, Smith College’s Achieving Excellence in Mathematics, Engineering, and Science (AEMES) Scholars program provides early faculty-mentored research opportunities and other programming as a way to foster success in academic outcomes for underrepresented women in science. Using academic record data, we compared Scholars’ outcomes over time with those of underrepresented students before program launch and to relevant peer comparison groups. Since its launch, AEMES Scholars have achieved significantly higher gateway life sciences course grade point averages (GPAs), rates of persistence in life and natural sciences, and participation in natural sciences advanced research relative to baseline. Gains for …
Earth News, V40, Spring 2017, University Of Northern Iowa. Department Of Earth And Environmental Sciences.
Earth News, V40, Spring 2017, University Of Northern Iowa. Department Of Earth And Environmental Sciences.
Earth News
Inside this issue:
-- From the Department Head Siobahn Morgan
-- Department Growth
-- Faculty Updates
-- SGE Newsletter
-- Congratulations 2016
-- Sunday at the Quarry
-- Alumni Spotlight: Aaron Stolley
-- Alumni Spotlight: Allyson Anderson
-- Congratulations to Faculty
-- Carver Grants
-- Hydrology News
-- Student Research
-- Donor Spotlight: Leslie Knapp
Precipitation Drivers Of Cropping Frequency In The Brazilian Cerrado: Evidence And Implications For Decision-Making, Keith R. Spangler, Amanda H. Lynch, Stephanie A. Spera
Precipitation Drivers Of Cropping Frequency In The Brazilian Cerrado: Evidence And Implications For Decision-Making, Keith R. Spangler, Amanda H. Lynch, Stephanie A. Spera
Geography and the Environment Faculty Publications
The Amazon basin has been subjected to unprecedented rates of land-use change over the past several decades, primarily as a result of the expansion of agriculture. Enhanced rain forest conservation efforts toward the end of the twentieth century slowed deforestation of the Amazon but, in turn, increased demand for land repurposing in the adjacent Cerrado (savanna) region, where conservation regulations are less strict. To maintain or increase yields while minimizing the need for additional land, agricultural producers adopted a form of intensification in which two rain-fed crops are planted within a single growing season (double cropping). Using 10 years (August …
Integrating The Field Of Prebiotic Chemistry Into A Christian Worldview, Matthew B. Anderson
Integrating The Field Of Prebiotic Chemistry Into A Christian Worldview, Matthew B. Anderson
Senior Honors Theses
This thesis will provide an overarching examination into the scientific field of prebiotic chemistry, the purported chemistry of the formation of life on earth. Prebiotic chemistry is a critical area of science particularly for Christian scientists to study since it is used by many evolutionists as evidence for the evolution of life, rather than the formation by an intelligent designer. Extensive literature-based research from previously published articles will be conducted on the formation of biologically necessary molecules, including amino acids. Primary focus will be placed on the formation of amino acids in a primordial earth environment, first demonstrated by the …
Evolution Characteristics Of Landscape Ecological Risk Patterns In Coastal Zones In Zhejiang Province, China, Jialin Li, Ruiliang Pu, Hongbo Gong, Xu Luo, Mengyao Ye, Baixiang Feng
Evolution Characteristics Of Landscape Ecological Risk Patterns In Coastal Zones In Zhejiang Province, China, Jialin Li, Ruiliang Pu, Hongbo Gong, Xu Luo, Mengyao Ye, Baixiang Feng
School of Geosciences Faculty and Staff Publications
Analyzing evolution characteristics of landscape ecological risk patterns would help establish ecological risk early warning mechanism, reduce the ecological risk probability and promote coastal landscape pattern optimization. In this study, landscape pattern indices were first calculated by using multitemporal Landsat TM images acquired in years 1990, 2000 and 2010, then landscape ecological risk pattern evolution models and the spatiotemporal evolutions of ecological risk patterns of coastal zones in Zhejiang province, China were constructed and analyzed. The results demonstrate that (1) greater changes have taken place in landscape structures during the two decades, and (2) the areas of cropland, sea, woodland …
Quantity Trumps Quality: Bayesian Statistical Accumulation Modeling Guides Radiocarbon Measurements To Construct A Chronology In Real-Time, Devon Robert Firesinger
Quantity Trumps Quality: Bayesian Statistical Accumulation Modeling Guides Radiocarbon Measurements To Construct A Chronology In Real-Time, Devon Robert Firesinger
USF Tampa Graduate Theses and Dissertations
The development of an accurate and precise geochronology is imperative to understanding archives containing information about Earth’s past. Unable to date all intervals of an archive, researchers use methods of interpolation to approximate age between dates. Sections of the radiocarbon calibration curve can induce larger chronological uncertainty independent of instrumental precision, meaning even a precise date may carry inflated error in its calibration to a calendar age. Methods of interpolation range from step-wise linear regression to, most recently, Bayesian statistical models. These employ prior knowledge of accumulation rate to provide a more informed interpolation between neighboring dates. This study uses …
Modeling The Movement Of Septic Water Chloride Through A Soil Profile, Shawkat Kochary, Tom Byl, Bahzad Noori
Modeling The Movement Of Septic Water Chloride Through A Soil Profile, Shawkat Kochary, Tom Byl, Bahzad Noori
Civil and Architectural Engineering Faculty Research
The purpose of this study was to investigate the movement of chloride through a vadose zone located under failed and non-regulated septic tanks of Duhok city, Kurdistan of Iraq, potentially contaminating its groundwater. A physical vadose model (PVM) of a vertical flow direction was built in the laboratory to represent the city soil profile. The size of the PVM was 210 × 122 × 9.7 cm (height, width, and depth). Preliminary soil tests were conducted to better represent the lithology of study area. The PVM was then packed with regional silt clay soil, after modifying its texture, using an innovative …
Molecular And Optical Properties Of Tree-Derived Dissolved Organic Matter In Throughfall And Stemflow From Live Oaks And Eastern Red Cedar, Aron Stubbins, Leticia M. Silva, Thorsten Dittmar, John T. Van Stan
Molecular And Optical Properties Of Tree-Derived Dissolved Organic Matter In Throughfall And Stemflow From Live Oaks And Eastern Red Cedar, Aron Stubbins, Leticia M. Silva, Thorsten Dittmar, John T. Van Stan
Earth, Environment & Sustainability: Faculty Publications
Studies of dissolved organic matter (DOM) transport through terrestrial aquatic systems usually start at the stream. However, the interception of rainwater by vegetation marks the beginning of the terrestrial hydrological cycle making trees the headwaters of aquatic carbon cycling. Rainwater interacts with trees picking up tree-DOM, which is then exported from the tree in stemflow and throughfall. Stemflow denotes water flowing down the tree trunk, while throughfall is the water that drips through the leaves of the canopy. We report the concentrations, optical properties (light absorbance) and molecular signatures (ultrahigh resolution mass spectrometry) of tree-DOM in throughfall and stemflow from …
Using Remote Sensing To Evaluate Wetland Recovery In The Northern Tampa Bay Area Following Reduction In Groundwater Withdrawals, Amor Elder
USF Tampa Graduate Theses and Dissertations
In the past, the Northern Tampa Bay Area (NTBA) wetlands saw severe declines in hydrologic conditions due to excessive groundwater withdrawal rates. Eventually these rates were reduced to allow the wetlands to recover. To monitor this recovery, the Southwest Florida Water Management district (SWFWMD) set up a fieldwork based scoring methodology, called the Wetlands Assessment Procedure (WAP). WAP has been used in many studies of the area since groundwater withdrawal reductions; with many of those studies finding the recovery to be mixed at best. However, these studies were very limited in the number of wetlands they could assess due to …
Factors That Influence Vital Rates Of Seaside And Saltmarsh Sparrows In Coastal New Jersey, Usa, Samuel G. Roberts, Rebecca A. Longenecker, Matthew A. Etterson, Katharine J. Ruskin, Chris S. Elphick, Brian J. Olsen, W. Gregory Shriver
Factors That Influence Vital Rates Of Seaside And Saltmarsh Sparrows In Coastal New Jersey, Usa, Samuel G. Roberts, Rebecca A. Longenecker, Matthew A. Etterson, Katharine J. Ruskin, Chris S. Elphick, Brian J. Olsen, W. Gregory Shriver
United States Environmental Protection Agency: Publications
As saltmarsh habitat continues to disappear, understanding the factors that influence the population dynamics of saltmarsh breeding birds is an important step in the conservation of these declining species. Using 5 yrs (2011–2015) of demographic data, we evaluated and compared apparent adult survival and nest survival of Seaside (Ammodramus maritimus) and Saltmarsh (A. caudacutus) sparrows at the Edwin B. Forsythe National Wildlife Refuge in New Jersey, USA. We determined the effect of site management history (unditched vs. ditched marshes) on adult and nest survival to aid in prioritizing future management or restoration actions. Apparent adult …