Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Institution
-
- Nova Southeastern University (39)
- University of Arkansas, Fayetteville (32)
- Purdue University (23)
- University of South Florida (17)
- University of Wisconsin Milwaukee (15)
-
- Old Dominion University (11)
- University of Tennessee, Knoxville (11)
- University of Vermont (11)
- University of Texas at El Paso (10)
- South Dakota State University (9)
- City University of New York (CUNY) (8)
- Portland State University (8)
- The University of Maine (8)
- University of Massachusetts Amherst (8)
- William & Mary (8)
- The University of Southern Mississippi (7)
- University at Albany, State University of New York (7)
- University of Nevada, Las Vegas (6)
- Utah State University (6)
- Wayne State University (6)
- Eastern Kentucky University (5)
- University of Kentucky (5)
- University of New Mexico (5)
- Washington University in St. Louis (5)
- Wilfrid Laurier University (5)
- Bowling Green State University (4)
- The University of San Francisco (4)
- Union College (4)
- Brigham Young University (3)
- Cal Poly Humboldt (3)
- Keyword
-
- Biological sciences (36)
- Health and environmental sciences (17)
- Pure sciences (13)
- Climate change (11)
- Social sciences (11)
-
- Applied sciences (10)
- Earth sciences (10)
- Climate Change (7)
- Conservation (7)
- Restoration (7)
- Ecology (6)
- Machine learning (6)
- Remote sensing (6)
- Deep learning (5)
- RNA (5)
- Resilience (5)
- Survival (5)
- Biodiversity (4)
- Deep Sea (4)
- GIS (4)
- Toxicity (4)
- Adaptation (3)
- Agriculture (3)
- Chemistry (3)
- Copper (3)
- Cyanobacteria (3)
- DNA (3)
- Erosion (3)
- Exposure (3)
- Fishing (3)
- Publication
-
- HCNSO Student Theses and Dissertations (33)
- Electronic Theses and Dissertations (26)
- Theses and Dissertations (26)
- Graduate Theses and Dissertations (25)
- USF Tampa Graduate Theses and Dissertations (17)
-
- Open Access Dissertations (15)
- Doctoral Dissertations (13)
- Honors Theses (12)
- Graduate College Dissertations and Theses (11)
- Masters Theses (11)
- Open Access Theses & Dissertations (10)
- Dissertations and Theses (9)
- Dissertations, Theses, and Masters Projects (8)
- Open Access Theses (8)
- Legacy Theses & Dissertations (2009 - 2024) (7)
- HCNSO Student Capstones (6)
- UNLV Theses, Dissertations, Professional Papers, and Capstones (6)
- Dissertations, Theses, and Capstone Projects (5)
- Honors Projects (5)
- Online Theses and Dissertations (5)
- Theses and Dissertations (Comprehensive) (5)
- All Graduate Theses and Dissertations, Spring 1920 to Summer 2023 (4)
- Biological Sciences Theses & Dissertations (4)
- Wayne State University Dissertations (4)
- Arts & Sciences Electronic Theses and Dissertations (3)
- Cal Poly Humboldt theses and projects (3)
- Chemistry & Biochemistry Undergraduate Honors Theses (3)
- Computer Science Theses & Dissertations (3)
- Dissertations, Master's Theses and Master's Reports (3)
- International Development, Community and Environment (IDCE) (3)
Articles 1 - 30 of 369
Full-Text Articles in Physical Sciences and Mathematics
Evolution In The Deep Sea: Scales And Mechanisms Of Population Divergence, Amanda E. Glazier
Evolution In The Deep Sea: Scales And Mechanisms Of Population Divergence, Amanda E. Glazier
Graduate Doctoral Dissertations
The deep sea is the Earth’s largest ecosystem and harbors a unique and largely endemic fauna. Although most research has focused on the ecological mechanisms that allow coexistence, recent studies have begun to investigate how this remarkable fauna evolved.. My work quantifies geographic patterns of genetic variation and investigates potential mechanisms that shape evolution in the deep ocean.
Bathymetric genetic divergence is common in the deep sea with population structure typically decreasing with depth. The evolutionary mechanisms that underlie these patterns are poorly understood. Geographic patterns of genetic variation indicated that the protobranch bivalve Neilonella salicensis was composed of two …
Impacts Of Long-Term Precipitation Manipulation On Hydraulic Architecture, Xylem Function, And Canopy Status In A Piñon-Juniper Woodland, Patrick J. Hudson
Impacts Of Long-Term Precipitation Manipulation On Hydraulic Architecture, Xylem Function, And Canopy Status In A Piñon-Juniper Woodland, Patrick J. Hudson
Biology ETDs
The Southwestern US is predicted to become hotter and drier, as global climate change forces increasing temperatures and variability in timing and size of precipitation inputs. Drought stress has become more frequent in recent decades, and resulted in massive forest mortality in piñon-juniper woodlands. During recent severe droughts (2000-2003, 2009-2012), piñon pine (Pinus edulis Englem.) suffered disproportionately high mortality compared to co-occurring one-seed juniper (Juniperus monosperma [Engelm.] Sarg.). A large-scale precipitation manipulation experiment was established in a piñon-juniper woodland in central New Mexico to test hypotheses regarding tree survival and mortality with respect to altered water regimes. Our …
Flight Of The Freshwater Fish, Michael H. Wilson
Flight Of The Freshwater Fish, Michael H. Wilson
Capstones
Michael H. Wilson
Capstone Abstract
December 27, 2016
Flight of the Freshwater Fish
The Hudson River provides for millions of people as a path for commercial and private transportation, a source of food and energy, and perhaps most importantly for many living in the tri-state area as a destination for recreation and relaxation. The most overlooked feature of the river is how the wildlife shows clear signs of a changing climate and rapid environmental response to the impacts of global warming on the river.
Entire populations of fish species in the lower Hudson have been forced to leave the river …
An Analysis Of Gulf Of Maine Cod Metapopulation Structure And Localized Stability, With Application To Area-Based Fisheries Management, Derek Olson
Electronic Theses and Dissertations
The complex metapopulation structure of groundfish stocks in the Gulf of Maine, particularly Atlantic cod (Gadus morhua), is largely ignored under the current system of broad-scale stock assessment and management. This mismatch of biological and administrative scales has contributed to severe overall stock decline and localized serial depletion of Gulf of Maine cod. Such chronic management failure has led to growing calls for a more area-based, finer-scale approach to managing groundfish in the Gulf of Maine. A primary difficulty hindering the development of finer-scale groundfish management has been the challenge of estimating fishing mortality upon local stock components. …
Roles Of Siphon Flows In Suspension Feeding, Kevin Du Clos
Roles Of Siphon Flows In Suspension Feeding, Kevin Du Clos
Electronic Theses and Dissertations
Benthic marine suspension feeders provide an important link between benthic and pelagic ecosystems. The strength of this link is determined by suspension-feeding rates. Many studies have measured suspension-feeding rates using indirect clearance-rate methods, which are based on the depletion of suspended particles. Direct methods that measure the flow of water itself are less common, but they can be more broadly applied because clearance-rate measurements are affected by properties of the cleared particles. We present pumping rates for three species of suspension feeders, the clams Mya arenaria and Mercenaria mercenaria and the tunicate Ciona intestinalis, calculated using a direct method …
Using Gis To Predict Cetacean Strandings Related To Harmful Algal Blooms, Jessica L. Boyd
Using Gis To Predict Cetacean Strandings Related To Harmful Algal Blooms, Jessica L. Boyd
HCNSO Student Capstones
Exposure to harmful algal bloom (HAB) toxins, such as Karenia brevis, has been linked to cetacean strandings and mortalities. Biological and environmental data from a bottlenose dolphin (Tursiops truncatus) Unusual Mortality Event (UME) in 2004 are compared to those from pilot whale (Globicephala macrorhynchus) mass stranding events in 2013-2014 in western Florida. Geographical Information Systems (GIS) maps have been created by overlaying stranding locations and select K. brevis presence data in order to identify common spatial and temporal trends. Preliminary results indicate that elevated K. brevis levels (>10,000 cells/L) in Sarasota Bay during January-February and November may …
A Review Of Present And Alternative Lionfish Controls In The Western Atlantic, Adam Rittermann
A Review Of Present And Alternative Lionfish Controls In The Western Atlantic, Adam Rittermann
HCNSO Student Capstones
Lionfish (Pterois volitans and Pterois miles) are the first recorded invasive piscivore in the Caribbean and have become a threat to native species. As generalist consumers, lionfish have a broad diet and reduce prey and competitor abundance and juvenile recruitment. To confront this problem, this paper serves to review all of the current and alternative future controls available to manage lionfish populations in the Western Atlantic and determine where focus is lacking. Derby and cull efforts are the only management efforts in place and are not effective in their current state as these local events have short-term benefits, …
An Evaluation Of The Seagrass Habitat In North Biscayne Bay, Florida, In Relation To A Changing Environment And Urbanization In The Port Of Miami Harbor Basin 2005-2011, Sara M. Jarossy
HCNSO Student Theses and Dissertations
Seagrass habitats in South Florida are exceptionally valuable. They play an important ecological role in the coastal environment by stabilizing sediment, providing habitat for other species and supporting a whole food web. The availability of light and nutrients in aquatic ecosystems are the driving factors behind seagrass distribution. Water quality has been known to influence the abundance, distribution and composition of seagrass beds. South Florida has extensive diverse coastal communities. Throughout its human development dramatic changes have occurred in its natural ecosystems. In South Florida, many examples of seagrass habitat loss are documented, with a variety of contributing factors. The …
Lilliput Effect Dynamics Across The Cretaceous-Paleogene Mass Extinction: Approaches, Prevalence, And Mechanisms, Matthew Brett Jarrett
Lilliput Effect Dynamics Across The Cretaceous-Paleogene Mass Extinction: Approaches, Prevalence, And Mechanisms, Matthew Brett Jarrett
USF Tampa Graduate Theses and Dissertations
An organism's body size entails both physiological and ecological costs. Furthermore, as a parameter in analyzing organisms, it represents a fundamental and essential morphometric character. Reductions in size following mass extinction is a commonly observed phenomenon in the fossil record. This study examines the evolutionary significance of this phenomenon termed the: 'Lilliput Effect' by proposing that it represents a rapid evolutionary response to altered selection pressures during a mass extinction. This primary hypothesis is evaluated against two additional hypotheses of size reduction: 1) stunted growth as a response to stressed ecosystems, and/or 2) mass extinctions are size selective.
These hypotheses …
Population Demographics And Sexual Reproduction Potential Of The Pillar Coral, Dendrogyra Cylindrus, On The Florida Reef Tract, Lystina Kabay
Population Demographics And Sexual Reproduction Potential Of The Pillar Coral, Dendrogyra Cylindrus, On The Florida Reef Tract, Lystina Kabay
HCNSO Student Theses and Dissertations
The pillar coral, Dendrogyra cylindrus, has been commonly described as widely distributed, but rare throughout its geographical range in the Caribbean. Having recently been listed as Threatened under the US Endangered Species Act, an understanding of population status is needed to promote species conservation and population recovery. Previous to this study the status of the pillar coral population in the state waters of Florida, U.S.A, was relatively unknown primarily due to few colonies being recorded and no comprehensive summary of population abundance, distribution or health being completed. Along with various environmental and anthropogenic factors affecting the pillar coral population …
Coral Recovery On Phase-Shifted Reefs Depend Upon The Type Of Macroalgae Present, Justin N. Voss
Coral Recovery On Phase-Shifted Reefs Depend Upon The Type Of Macroalgae Present, Justin N. Voss
HCNSO Student Theses and Dissertations
The Florida Keys experienced some of the most drastic transitions from coral to macroalgae dominated states, known as phase-or regime-shifts, of any reefs in the Caribbean. Macroalgae on coral reefs lower coral recruitment by deterring coral settlement either directly through competition or indirectly by changing the chemical environment near the benthos. With evidence of species-specific interactions to coral-macroalgae competition, the type of macroalgae on a phase-shifted coral reef might be more important than just identifying a reef transition. To answer this question, I tested the effect of Laurencia intricata (a macroalgae related to the settlement inducing crustose coralline algae) and …
Effects Of 17 Β-Estradiol And Progesterone On Acropora Cervicornis And Porites Astreoides Growth And Reproduction, Joshua L. Stocker
Effects Of 17 Β-Estradiol And Progesterone On Acropora Cervicornis And Porites Astreoides Growth And Reproduction, Joshua L. Stocker
HCNSO Student Theses and Dissertations
Reef-building coral populations throughout the world are being threatened by numerous stressors and continue to decline. As potent endocrine-disrupting compounds, exogenous sex steroid contamination has been a largely overlooked stressor to corals. Previous research indicates these compounds are prevalent in marine environments, fluctuate annually along with reproductive cycles, can bioaccumulate, and have had variable effects on growth and reproduction in several cnidarian species. This project had three primary objectives: (1) establish environmental estradiol and progesterone concentrations in Broward County and lower Florida Keys reef environments, (2) conduct 17 β-estradiol and progesterone larval assays on P. astreoides larvae to determine the …
The Vertical And Horizontal Distribution Of Deep-Sea Crustaceans Of The Order Euphausiacea (Malacostraca: Eucarida) From The Northern Gulf Of Mexico With Notes On Reproductive Seasonality., Charles Douglas Fine
The Vertical And Horizontal Distribution Of Deep-Sea Crustaceans Of The Order Euphausiacea (Malacostraca: Eucarida) From The Northern Gulf Of Mexico With Notes On Reproductive Seasonality., Charles Douglas Fine
HCNSO Student Theses and Dissertations
The vertical and horizontal distributions of Euphausiacea in the northern Gulf of Mexico, including the location of the Deepwater Horizon oil spill, were analyzed from 340 trawl samples collected between April-June, 2011. This study is the first comprehensive survey of euphausiid distributions from depths deeper than 1000 m in the Gulf of Mexico and included stratified sampling from five discrete depth ranges (0-200 m, 200-600 m, 600-1000 m, 1000-1200 m, and 1200-1500 m). In addition, this study encompasses the region heavily impacted by the Deepwater Horizon oil spill. Data presented here could potentially be used in ecosystem models investigating trophic …
Trophic Ecology Of Green Turtles (Chelonia Mydas) From Dry Tortugas National Park, Florida, David C. Roche
Trophic Ecology Of Green Turtles (Chelonia Mydas) From Dry Tortugas National Park, Florida, David C. Roche
HCNSO Student Theses and Dissertations
Located 100 km west of Key West, Florida, Dry Tortugas National Park (DRTO) is a largely untouched subtropical marine ecosystem that serves as an important developmental habitat, nesting ground, and foraging area for several species of sea turtles, including green turtles. The Park supports a recovering population of green turtles comprised of resident juveniles, subadults, and adults of both sexes; nesting females include residents and migrating females that only return to nest. Stable isotope analysis has been applied widely to describe the trophic ecology of green turtles, from urbanized bays with significant anthropogenic input, to relatively pristine ecosystems with healthy …
Determining The Impacts Of Environmental Contaminants To Zebra Mussels Using Genetic Biomarkers, Nicklaus James Neureuther
Determining The Impacts Of Environmental Contaminants To Zebra Mussels Using Genetic Biomarkers, Nicklaus James Neureuther
Theses and Dissertations
ABSTRACT
DETERMINING THE IMPACTS OF ENVIRONMENTAL CONTAMINANTS TO ZEBRA MUSSELS USING GENETIC BIOMARKERS
by
Nicklaus James Neureuther
The University of Wisconsin-Milwaukee, 2016
Under the Supervision of Professor Rebecca Klaper, PhD
Persistent legacy contaminants and emerging chemicals of concern continue to be a threat to the function and health in the Great Lakes Areas of Concern (AOCs). While chemical monitoring programs traditionally sample water and sediment, these studies can only provide information of the type and level of contamination within an (AOC). This being said, information on the biological impacts to the biota are needed to measure impairments of chemical exposure, …
Determining The Effects Of The Think Risk Initiative As Implemented By The Southern Nevada Health District, Karalin Nichole Cronkhite
Determining The Effects Of The Think Risk Initiative As Implemented By The Southern Nevada Health District, Karalin Nichole Cronkhite
UNLV Theses, Dissertations, Professional Papers, and Capstones
In the United States, someone becomes infected with a foodborne illness every 2 seconds, is hospitalized by a foodborne illness every 4 minutes and dies due to a foodborne illness every 3 hours. Foodborne illness is preventable, yet each year, 1 in 6 Americans is affected by it from contaminated foods or beverages. There are over 250 different foodborne diseases, and in 2015, there were 73 confirmed cases of Salmonella infection in Southern Nevada alone. Since the emergence of public health, food establishment inspections have been an important part of the regulation of food safety. Risk-based inspections were developed by …
Electrogenerated Chemiluminescence Study Of Semiconductor Nanoparticles Towards Sensitive Detection Of Biomolecules, Yiliyasi Wusimanjiang
Electrogenerated Chemiluminescence Study Of Semiconductor Nanoparticles Towards Sensitive Detection Of Biomolecules, Yiliyasi Wusimanjiang
Dissertations
The main focus of this dissertation is to unfold the fundamental aspects of electrogenerated chemiluminescence (ECL) generation from semiconductor nanoparticles (also known as quantum dots or QDs) within different ECL systems. The ECL and photo-physical interactions between the CdTe QDs (λemission= ~760 nm) and the CdSe QDs (λemission= ~550 nm), as well as the effects of carbon nanotubes on ECL of QDs were separately investigated. Optimum experimental conditions for peptide bond formation on an electrode surface through EDC (1-ethyl-3-(-3-dimethylaminopropyl) carbodiimide hydrochloride)/NHS (N-Hydroxysulfosuccinimide) coupling were also revealed using cyclic voltammetry technique. Based on the information …
A Framework For The Statistical Analysis Of Mass Spectrometry Imaging Experiments, Kyle Bemis
A Framework For The Statistical Analysis Of Mass Spectrometry Imaging Experiments, Kyle Bemis
Open Access Dissertations
Mass spectrometry (MS) imaging is a powerful investigation technique for a wide range of biological applications such as molecular histology of tissue, whole body sections, and bacterial films , and biomedical applications such as cancer diagnosis. MS imaging visualizes the spatial distribution of molecular ions in a sample by repeatedly collecting mass spectra across its surface, resulting in complex, high-dimensional imaging datasets. Two of the primary goals of statistical analysis of MS imaging experiments are classification (for supervised experiments), i.e. assigning pixels to pre-defined classes based on their spectral profiles, and segmentation (for unsupervised experiments), i.e. assigning pixels to newly …
Quantifying Terrestrial Ecosystem Carbon Dynamics With Mechanistically-Based Biogeochemistry Models And In Situ And Remotely Sensed Data, Shaoqing Liu
Open Access Dissertations
Terrestrial ecosystem plays a critical role in the global carbon cycle and climate system. Therefore, it is important to accurately quantify the carbon dynamics of terrestrial ecosystem under future climatic change condition. This dissertation evaluates the regional carbon dynamics by using upscaling approach, mechanistically-based biogeochemistry models and in situ and remotely sensed data.
The upscaling studies based on FLUXNET network has provided us the spatial and temporal pattern of the carbon fluxes but it fails to consider the atmospheric CO2 effect given its important physiological role in carbon assimilation. In the second chapter, we consider the effect of atmospheric CO2 …
Annual Forage Cropping-Systems For Midwestern Ruminant Livestock Production, John Ernest Mcmillan
Annual Forage Cropping-Systems For Midwestern Ruminant Livestock Production, John Ernest Mcmillan
Open Access Dissertations
Annual forage cropping systems are a vital aspect of livestock forage production. One area where this production system can be enhanced is the integration of novel annual forages into conventional cropping systems. Two separate projects were conducted to investigate alternative forage options in annual forage production. In the first discussed research trial, two sets of crops were sown following soft red winter wheat (Triticum aestivum L.) grain harvest, at two nitrogen application rates 56 and 112 kg ha-1 . The first set of crops were C4 summer annuals seeded within two weeks of wheat grain harvest and included, brown …
Characterizing The Effects Of Repetitive Head Trauma In Female Soccer Athletes For Prevention Of Mild Traumatic Brain Injury, Diana Otero Svaldi
Characterizing The Effects Of Repetitive Head Trauma In Female Soccer Athletes For Prevention Of Mild Traumatic Brain Injury, Diana Otero Svaldi
Open Access Dissertations
As participation in women’s soccer continues to grow and the longevity of female athletes’ careers continues to increase, prevention of mTBI in women’s soccer has become a major concern for female athletes as the long-term risks associated with a history of mTBI are well documented. Among women’s sports, soccer exhibits the highest concussion rates, on par with those of men’s football at the collegiate level. Head impact monitoring technology has revealed that “concussive hits” occurring directly before symptomatic injury are not predictive of mTBI, suggesting that the cumulative effect of repetitive head impacts experienced by collision sport athletes should be …
Synthesis And Performance Of Novel Supramolecular Tools For Single-Particle Cryogenic Electron Microscopy And Drug And Gene Delivery, Kyle J. Wright
Synthesis And Performance Of Novel Supramolecular Tools For Single-Particle Cryogenic Electron Microscopy And Drug And Gene Delivery, Kyle J. Wright
Open Access Dissertations
High-resolution biomacromolecular structure elucidation is fundamentally important to structure-based drug design and basic research into complex biochemical processes. Cryo-EM is an emerging alternative to XRD and NMR that is complementary in many ways relative to XRD and NMR. Materials approaches to cryo-EM are anticipated to greatly facilitate the cryo-EM process, allowing progress toward a more high-throughput application of cryo-EM to address challenges in structural biology. ^ Various affinity-based approaches inspired by approaches previously introduced for 2D crystallization were developed for facilitation of cryo-EM. A library of affinity lipopolymer constructs were synthesized consisting of lipopolymers of various PEG molecular weights conjugated …
Lower Food Web Dynamics In Lakes Michigan And Huron: Spatial And Temporal Responses To Recent Oligotrophication, Margaret Hutton Stadig
Lower Food Web Dynamics In Lakes Michigan And Huron: Spatial And Temporal Responses To Recent Oligotrophication, Margaret Hutton Stadig
Open Access Theses
Nutrient abatement programs, originally enacted to counter eutrophication have successfully suppressed nutrient loads and relative primary production in marine and freshwater systems. Recently, the additive impacts of invasive filter feeders have further reduced offshore primary production in several aquatic systems throughout the world. It has been hypothesized that the biological activity of these invasive species may sequester nutrients within the nearshore benthic environment, creating steep gradients in primary production between nearshore and offshore habitats. In the Laurentian Great Lakes, past studies of oligotrophication have primarily focused on food web responses in offshore habitats. Organisms at higher trophic levels have been …
Mathematical Analysis Of Feedback Targets Of Bmp Signaling In Drosophila Embryonic Development, Yan Luo
Mathematical Analysis Of Feedback Targets Of Bmp Signaling In Drosophila Embryonic Development, Yan Luo
Open Access Theses
Bone morphogenetic proteins (BMPs) drive a range of cellular processes especially in the early stages of embryonic development. This family of proteins acts as one of the most important extracellular signals in development pattern formation across the animal kingdom. Cells in embryos differentiate into different cell types in response to the concentration level of BMP. This complex process is regulated by multiple regulators that serve to tune the signal response.
Extensive experimental and computational research has been performed to analyze BMP regulation in Drosophila, a widely studied model organism, and has advanced our understanding of animal development. Because of …
Residual Effects Of Nitrogen Fertilization On Soil Nitrogen Pools And Corn Growth, Meghan E. Moser
Residual Effects Of Nitrogen Fertilization On Soil Nitrogen Pools And Corn Growth, Meghan E. Moser
Open Access Theses
Given the dynamic nature of soil nitrogen (N), inorganic N fertilization to corn (Zea mays L.) has potential to alter N pool balance by creating an accumulation or depletion of soil N. Current corn N recommendations in the common corn-soybean rotation of Indiana strive to find the best N rate that maximizes producer profit. Increasing our understanding of soil N will inform producers if they should adjust fertilizer rates for corn to influence maintenance of organic N and Carbon. Our objective was to determine residual N effects from fertilized corn in a corn-soybean rotation by measuring (1) soil N …
Gonadal Intersex In Teleosts: Mechanisms, Molecular Biomarkers And Diagnostic Assays, Ahmed M.E. Abdel-Moneim Mohamed
Gonadal Intersex In Teleosts: Mechanisms, Molecular Biomarkers And Diagnostic Assays, Ahmed M.E. Abdel-Moneim Mohamed
Open Access Dissertations
Natural and synthetic estrogenic and androgenic compounds are continuously released into aquatic ecosystems. Exposure of teleost fishes to these contaminants can negatively impact sex differentiation and reproductive output. Specifically, development of gonadal intersex in gonochoristic (fixed sex) fish species has been studied extensively in relation to exposure to this class of compounds. The main objectives of this dissertation were to: 1) conduct field and laboratory studies to investigate the molecular signaling pathways behind the development of gonadal intersex; and 2) establish molecular biomarkers and assays for testing the ability of environmental pollutants to develop this condition using a battery of …
A Study Of Short-Season Winter Cover Crops For Organic High Tunnel Production Systems, Luke Riley Freeman
A Study Of Short-Season Winter Cover Crops For Organic High Tunnel Production Systems, Luke Riley Freeman
Graduate Theses and Dissertations
This two-year study investigated short-season winter cover crops to improve soil quality and growth of subsequent vegetable crops in an organic high tunnel production system. Five winter cover crop treatments including a nontreated control, Austrian winter peas (Pisum arvense), bell beans (Vicia faba), mustard (Brassica juncea cv. Kodiak), and Daikon radish (Raphanus sativus var. longipinnatus) were grown in a high tunnel in a randomized complete block design from mid-November to mid-March, mowed and incorporated into the soil, and followed by a succession of vegetable crops including tomato (Lycopersicon lycopersicum, cv. ‘Plum Dandy’) and broccoli (Brassica oleracea var. italica, cv. ‘Bay …
On The Quantification Of Complexity And Diversity From Phenotypes To Ecosystems, Zachary Harrison Marion
On The Quantification Of Complexity And Diversity From Phenotypes To Ecosystems, Zachary Harrison Marion
Doctoral Dissertations
A cornerstone of ecology and evolution is comparing and explaining the complexity of natural systems, be they genomes, phenotypes, communities, or entire ecosystems. These comparisons and explanations then beget questions about how complexity should be quantified in theory and estimated in practice. Here I embrace diversity partitioning using Hill or effective numbers to move the empirical side of the field regarding the quantification of biological complexity.
First, at the level of phenotypes, I show that traditional multivariate analyses ignore individual complexity and provide relatively abstract representations of variation among individuals. I then suggest using well-known diversity indices from community ecology …
Willingness To Pay For Irrigation Water Under Scarcity Conditions, Tyler Robert Knapp
Willingness To Pay For Irrigation Water Under Scarcity Conditions, Tyler Robert Knapp
Graduate Theses and Dissertations
Reliance of Arkansas agricultural producers on groundwater for irrigation has led to depletion of the Mississippi River Valley alluvial aquifer. Without intervention, consequences include insufficient groundwater to meet irrigation demand as well as drawdown of the deeper Sparta Aquifer, upon which communities in eastern Arkansas rely for non-agricultural use. Among proposed solutions to combat groundwater decline is the construction of off-farm surface water infrastructure to meet the irrigation needs of producers. Despite the importance of irrigated agriculture to Arkansas, there is little know about the economic value of irrigation water to producers. Thus, we implement a double-bounded dichotomous choice contingent …
Soil And Plant Property Differences Among High-Yield Soybean Areas In Arkansas, Taylor Cass Adams
Soil And Plant Property Differences Among High-Yield Soybean Areas In Arkansas, Taylor Cass Adams
Graduate Theses and Dissertations
Continued achievement of soybean [Glycine max (L.) Merr.] yields greater than 6719 kg ha-1 (100 bu ac-1) will depend on decreasing the yield gap, which is contingent on gathering more information regarding the soil physical, chemical, and microbiological environment and the main plant factors contributing to high-yield soybean. Therefore, understanding the main factor differences between high- and average-yield areas may provide insight for making management decisions to increase yields. The objectives of this study were i) to evaluate the effects of region and soil depth on soil property differences between high- and average-soybean-yielding areas, ii) to determine which soil properties …