Digital Commons Network^™

Disaster Resilience Versus Ecological Resilience And The Proposed Second Causeway To South Padre Island, Juliet Vallejo, Katia Sanchez, Evelyn Roozee, Owen Temby

School of Earth, Environmental, & Marine Sciences Faculty Publications

The barrier island of South Padre is located off the coast of Texas’s southern tip in Cameron County and is a popular tourist destination with over 4 million annual visits. The only road access to and from the island is a four-lane causeway, 2.3 miles in length, that routinely experiences heavy traffic. Twenty years ago, a barge crashed into the Queen Isabella Causeway, destroying a portion of the bridge. It quickly became apparent how reliant South Padre Island (SPI) is on the causeway and raised questions regarding its lack of disaster resilience. Local boosters and government responded by proposing and …

Learning From Machines: Insights In Forest Transpiration Using Machine Learning Methods, Morgan Thornwell

Dissertations and Theses

Machine learning has been used as a tool to model transpiration for individual sites, but few models are capable of generalizing to new locations without calibration to site data. Using the global SAPFLUXNET database, 95 tree sap flow data sites were grouped using three clustering strategies: by biome, by tree functional type, and through use of a k-means unsupervised clustering algorithm. Two supervised machine learning algorithms, a random forest algorithm and a neural network algorithm, were used to build machine learning models that predicted transpiration for each cluster. The performance and feature importance in each model were analyzed and compared …

Science Of The Total Environment, Benjamin Linhoff

United States Geological Survey: Staff Publications

Recently, the subsoils of ephemeral stream(arroyos) floodplains in the northern Chihuahuan Desert were discovered to contain large naturally occurring NO₃⁻ reservoirs (floodplain:~38,000 kg NO₃-N/ha; background:~60 kg NO₃-N/ha). These reservoirs may be mobilized through land use change or natural stream channel migration which makes differentiating between anthropogenic and natural groundwaterNO₃⁻sources challenging. In this study, the fate and sources of NO₃⁻ were investigated in an area with multiple NO₃⁻ sources such as accidental sewer line releases and sewage lagoons aswell as natural reservoirs of subsoil NO₃⁻. …

Characterization Of Mumian And Host Rock In Al-Amerat Cave, Oman., Sara Alqamshouai

Honors Theses

Mumian is a sticky black-brown material found in the Mumian cave in Wadi Al Mayh, Al Amerat, Oman. Mumian has been used for centuries as traditional medicine by the local Omani people. Though commonly ingested orally to resolve a variety of common ailments, very little is known about the Mumian material in terms of its chemical composition. The principle aim of this study is to characterize the Mumian and the host rock in terms of the mineralogy and chemical characteristics using a variety of analytic instruments, including XRD, NMR, FT-IR, XRF, and UV- VIS. A secondary goal of this study …

Coexistence Of Vitreous And Crystalline Phases Of H2o At Ambient Temperature, Ali K. Shargh, Aude Picard, Rostislav Hrubiak, Dongzhou Zhang, Russell J. Hemley, Shanti Deemyad, Niaz Abdolrahim, Saveez Saffarian

Life Sciences Faculty Research

Formation of vitreous ice during rapid compression of water at room temperature is important for biology and the study of biological systems. Here, we show that Raman spectra of rapidly compressed water at greater than 1 GPa at room temperature exhibits the signature of high-density amorphous ice, whereas the X-ray diffraction (XRD) pattern is dominated by crystalline ice VI. To resolve this apparent contradiction, we used molecular dynamics simulations to calculate full vibrational spectra and diffraction patterns of mixtures of vitreous ice and ice VI, including embedded interfaces between the two phases. We show quantitatively that Raman spectra, which probe …

From Soils To Streams: Connecting Terrestrial Carbon Transformation, Chemical Weathering, And Solute Export Across Hydrological Regimes, Alejandro Flores, Katie Murenbeeld

Geosciences Faculty Publications and Presentations

Soil biota generates carbon that exports vertically to the atmosphere (CO₂) and transports laterally to streams and rivers (dissolved organic and inorganic carbon, DOC and DIC). These processes, together with chemical weathering, vary with flow paths across hydrological regimes; yet an integrated understanding of these interactive processes is still lacking. Here we ask: How and to what extent do subsurface carbon transformation, chemical weathering, and solute export differ across hydrological and subsurface structure regimes? We address this question using a hillslope reactive transport model calibrated using soil CO₂ and water chemistry data from Fitch, a temperate forest …

Arkansas Corn And Grain Sorghum Research Studies 2021, Victor Ford, Jason Kelley, Nathan Mckinney Ii

Arkansas Agricultural Experiment Station Research Series

The 2021 edition of the Arkansas Corn and Grain Sorghum Research Studies Series includes research results on topics pertaining to corn and grain sorghum production, including weed, disease, and insect management; economics; sustainability; irrigation; post-harvest drying; soil fertility; mycotoxins; cover crop management; and research verification program results. Our objective is to capture and broadly distribute the results of research projects funded by the Arkansas Corn and Grain Sorghum Board. The intended audience includes producers and their advisors, current investigators, and future researchers. The Series serves as a citable archive of research results.

Effects Of Nutrient Enrichment On Mangrove And Saltmarsh Habitats, Elena A. Flores

Theses and Dissertations

Nutrient over-enrichment is a global threat to coastal and marine environments. Yet, system-specific attributes of estuarine and coastal ecosystems may result in large differences in their sensitivity and susceptibility to such threat. In tropical latitudes, plant species adapted to low-nutrient habitats generally have nutrient-conservation mechanisms that acquire, use, and internally recycle nutrients efficiently. Thus, a major challenge for managers and decision makers is to develop a predictive and holistic understanding of how nutrient loading alters ecosystem functions and therefore ecosystem services. The objective of the present research is to document short and long-term effects of persistent nutrient …

Tropical Cyclone Storm Surge Detection In Slash Pine Radial Growth Along The Northern Gulf Of Mexico Coastline, Alyssa C. Crowell

Master's Theses

My thesis examines the ecological impact of tropical cyclone (TCs) storm surge on coastal slash pine (Pinus elliottii var. elliottii Engelm) communities along the Gulf of Mexico in the southern United States (U.S.). Previous research has shown slash pine radial growth trends can be examined to identify long and short-term growth changes associated with TC passage, providing insight into overall stand health and resiliency through time. However, this previous research encompasses just one site in Mississippi. My thesis expands the spatial footprint of TC-surge impact on slash pine radial growth with the addition of three new sites.

I examined …

Phytochemical, Antibacterial, Antifungal, And Hemagglutination Screening Of Quercus Agrifolia Nee Root Extracts, Abdul Wahab, Arshad Farid, Muhammad Muzammal

Makara Journal of Science

In the current study, the roots of Quercus agrifolia Nee were subjected to phytochemical analysis to determine the presence of various compound groups. To explore the effect of Quercus agrifolia Nee roots, we evaluated four solvent extracts, namely, crude ethanolic extract (CEE), n-hexane, chloroform (CHCl₃), and ethyl acetate (EtOAc), for their antibacterial, antifungal, and hemagglutination activities. Agar well diffusion and agar tube dilution methods were used to determine the antibacterial and antifungal effects, respectively, and hemagglutination activity was measured against human erythrocyte blood groups. The qualitative phytochemical analysis of the solvent extracts of Quercus agrifolia Nee roots …

Silver Nanoparticles’ Biosynthesis And Characterization With The Extract Of Jatropha Curcas Leaf: Analysis Of Corrosion Inhibition Activity, Talabi Henry Kayode, Talabi Justina Yetunde, Adewuyi Benjamin Omotayo

Makara Journal of Science

The plant-mediated nanoparticles synthesis process is gaining popularity because of its effective cost, eco-friendliness, and nontoxic nature. The current study presents the silver nanoparticles (AgNPs) which synthesized with AgNO₃ as precursor salt and Jatropha curcas leaf extract. J. curcas leaf extract has phytochemicals that could reduce the precursor metal salt to nanoparticles and act as a capping agent surround the nanoparticles to enhance its stability. Phytochemical screening on J. curcas leaf extract showed that alkaloids, saponins, tannins, flavanoids, steroids, philobatannins, phenols, and cardiac glycosides are contained in the sample. The biosynthesized nanoparticles were investigated by UV-visible (UV-vis) spectroscopy, X-ray …

Jatropha Tanjorensis A Flora Of Southeast Nigeria: Isolation And Characterization Of Naringenin And Validation Of Bio-Enhanced Synergistical Activity Of Α- Tocopherol Toward Clinical Isolates Of Resistant Bacterial, Ikechukwu Kingsley Ijoma, Vincent Ishmael Egbulefu Ajiwe

Makara Journal of Science

Jatropha tanjorensis is among the rich floras of Southeast Nigeria and used by ethnic people to treat infections and manage health conditions. Ethnomedicine has long been employed in the treatment of ailments caused by bacterial pathogens. Studies showed that the incorporation of synthetic α-tocopherol to an antibacterial agent improves its activity. However, knowledge about the antibacterial-enhanced activity of plant-based α-tocopherols, especially those isolated from Jatropha tanjorensis, is limited because of the different bioactivities of synthetic and natural α-tocopherols. To determine the phytochemicals in J. tanjorensis, we carried out the structural elucidation of its leaf extracts. Naringenin and α-tocopherol …

Evaluation Of Natural Radioactivity And Radiation Hazards Of Soils Around Petroleum Products Marketing Company Using Gamma Ray Spectrometry, Dayo A. Ayeni, Festus M. Adebiyi

Tanzania Journal of Science

This study aimed at evaluating natural radioactivity and radiation hazards of soils around a petroleum product marketing company due to anthropogenic influences using gamma ray spectrometry. Top soils (5 cm deep) were collected from diverse locations inside the premises of the Company using standard analytical technique, while control samples were acquired at approximately 200 m from the study area. Mean activity concentrations of the radionuclides in the test soils were 89.36 Bq/kg for 40K, 92.1 Bq/kg for 238U and 10.95 Bq/kg for 232Th, which are more than that of control samples with statistically significant differences. Assessment of the radiological levels …

Charcoal Whirlwinds And Post-Fire Observations In Serengeti National Park Savannahs, Colin J. Courtney Mustaphi, Heleen C. Vos, Rob Marchant, Colin Beale

Tanzania Journal of Science

Whirlwinds and visible dust devils occur over semi-arid ecosystems and entrain particles from the ground surface. Fires produce abundant charcoal across savannahs and the resulting blackened surfaces create a large albedo contrast. Whirlwinds have been observed associated with active fires; yet, there are few published observations on post-fire landscapes. Spatiotemporal patterns of whirlwinds have been documented for a limited number of regions and have not been made for the ecosystems of eastern Africa. From field-based sightings in the Serengeti National Park, Tanzania, we report on whirlwinds over burned savannah patches that entrained large quantities of charcoal to produce black coloured …

Critical P, K And S Concentrations In Soil And Shoot Samples For Optimal Tedera Productivity And Nodulation, Daniel Real, Richard G. Bennett, Nazanin K. Nazeri, David M. Weaver

Grain and Other Field Crops Research Articles

Tedera is a forage legume that can provide out-of-season green feed in Mediterranean climates. To date, growers have had no comprehensive soil nutrition guidelines to optimise tedera production. We undertook field and glasshouse studies to understand tedera’s macronutrient requirements. Three field experiments were sown with tedera cv. Lanza® at Cunderdin, Dandaragan and Three Springs in Western Australia. These experiments evaluated seven levels of phosphorus (P) (0–30 kg ha−1) and potassium (K) (0–80 kg ha−1) and two combined treatments with P and K. Glasshouse pot experiments were conducted using tedera cultivars Lanza® and Palma and lucerne cultivar SARDI Grazer. Ten concentrations …

We Must Stop Fossil Fuel Emissions To Protect Permafrost Ecosystems, Benjamin W. Abbott, Michael Brown, Joanna C. Carey, Jessica G. Ernakovich, Jennifer M. Frederick, Laodong Guo, Gustaf Hugelius, Raymond M. Lee, Michael M. Loranty, Robie Macdonald, Paul J. Mann, Susan M. Natali, David Olefeldt, Pam Pearson, Abigail Rec, Martin Robards, Verity G. Salmon, Sara Sayedi, Christina Schadel, Edward A. G. Schuur, Sarah Shakil, Arial J. Shogren, Jens Strauss, Suzanne E. Tank, Brett F. Thornton, Rachael Treharne, Merritt Turetsky, Carolina Voigt, Nancy Wright, Yuanhe Yang, Jay P. Zarnetske, Qiwen Zhang, Scott Zolkos

Faculty Publications

Climate change is an existential threat to the vast global permafrost domain. The diverse human cultures, ecological communities, and biogeochemical cycles of this tenth of the planet depend on the persistence of frozen conditions. The complexity, immensity, and remoteness of permafrost ecosystems make it difficult to grasp how quickly things are changing and what can be done about it. Here, we summarize terrestrial and marine changes in the permafrost domain with an eye toward global policy. While many questions remain, we know that continued fossil fuel burning is incompatible with the continued existence of the permafrost domain as we know …

Biomass Residues Improve Soil Chemical And Biological Properties Reestablishing Native Species In An Exposed Subsoil In Brazilian Cerrado, Thaís Soto Boni, Engil Isadora Pujol Pereira, Adriana Avelino Santos, Ana Maria Rodrigues Cassiolato, Kátia Luciene Maltoni

School of Earth, Environmental, & Marine Sciences Faculty Publications

Revegetation of exposed sub-soil, while a desirable strategy in the recovery processes, often fails due to extreme soil chemical properties, such as low organic matter and pH levels inhospitable to biological activities such as nutrients cycling and plant establishment. This is the case for approximately 800 ha of the Cerrado biome in Brazil, where erecting the embankment of a hydroelectric dam in the 1960’s stripped vegetation, soil, and subsoil layers thereby distorting the soil properties. This work evaluates the effectiveness of restoration management (RM) treatments, to restore the soil quality, including biological activity and chemical attributes. In a factorial scheme, …

Effect Of Kaolin On Biogenic Coalbed Methane Production And The Response Of Microbial Community, He Huan, Huang Xinying, Huang Zaixing, Zhang Qian, Chen Zihao, Zhao Han, Ren Hengxing, Huang Guanhua

Coal Geology & Exploration

Kaolin is a common inorganic mineral in nature, which can promote the growth and metabolism of microorganisms. There is a large amount of kaolin in coal, however, there are few reports about its bio-gas production of coal. In order to investigate the effect of kaolin on biogas production, the coal obtained from Yulin, Shaanxi Province was taken as the research object, domesticated microorganisms were taken as the research flora, and different qualities of kaolin were added into the culture media to make biological simulation of gas production. The changes of CH₄ content, volatile fatty acids (VFAs) concentration, coenzyme F …

Sequence-Paleogeography And Coal Accumulation Of The Paleogene Hunchun Formation In The Hunchun Basin, Hou Haihai, Li Qiangqiang, Shao Longyi, Fan Xuejie, Liang Guodong, Li Yanan

Coal Geology & Exploration

The Hunchun Basin is an important coal-bearing region in Jilin Province, northeastern China. The analysis of the sedimentary paleogeography of the Paleogene Hunchun Formation and coal-accumulation law in the sequence framework provides a theoretical basis for future coal and coalbed methane exploration. The lithofacies, sedimentary systems, sequence paleogeography, and coal accumulation characteristics were analyzed based on regional geology, drilling cores and well logging data. The results show five rock types, including gravel, sandstone, siltstone, mudstone, and combustible organic rock, and twelve lithofacies. The Hunchun Formation was divided into three third-order sequences by three sequence interfaces, including the regional unconformity surface, …

Sedimentary Characteristics And Associated Carbon And Nutrients Of Overbank Sediments Deposited During The 2018, 2019, And 2020 Floods In Embanked Floodplains Along The Lower Mississippi River Near Natchez, Mississippi, Rachel Kelk

Master's Theses

The Lower Mississippi River (LMR) experienced major floods in 2018, 2019, and 2020. Sediment deposition in the embanked floodplains during floods represent important storage and sequestration opportunities for carbon and nutrients from ~40% of the continental USA. This research aims to compare depositional thicknesses, organic matter (OM), carbon (C), nitrogen (N), phosphorous (P) concentrations, and grain sizes in floodplain sediments deposited by the combined 2018-19 floods to the 2020 flood along the LMR near Natchez, Mississippi. Greater depositional thicknesses in 2018-19 are best explained by their combined flood durations; the 2019 flood was the longest in recorded history. Slightly higher …

A Participatory Assessment Of Nitrified Urine Fertilizer Use In Swayimane, South Africa: Crop Production Potential, Farmer Attitudes And Smallholder Challenges, Benjamin C. Wilde, Eva Lieberherr, Engil Isadora Pujol Pereira, Alfred Odindo, Johan Siz

School of Earth, Environmental, & Marine Sciences Faculty Publications

Long-term nutrient mining of soil hampers agricultural production across Africa. However, emerging sanitation technologies afford a hygienically safe and ecologically sustainable solution to this development challenge by providing fertilizers derived from human excreta that could facilitate a socio-technical transition toward a more sustainable food system. To evaluate one such technology, nitrified urine fertilizer (NUF), we conducted participatory action research to assess the potential, from both a biophysical and social perspective, of NUF to serve as a soil fertilizer to support smallholder agricultural production in Swayimane, South Africa. To achieve this objective, we formed a stakeholder group comprised of a cooperative …

Population Genetics Reveals Bidirectional Fish Movement Across The Continental Divide Via An Interbasin Water Transfer, Audrey C. Harris, Sara J. Oyler-Mccance, Jennifer A. Fike, Matthew P. Fairchild, Christopher M. Kennedy, Harry J. Crockett, Dana L. Winkelman, Yoichiro Kanno

United States Geological Survey: Staff Publications

Interbasin water transfers are becoming an increasingly common tool to satisfy municipal and agricultural water demand, but their impacts on movement and gene flow of aquatic organisms are poorly understood. The Grand Ditch is an interbasin water transfer that diverts water from tributaries of the upper Colorado River on the west side of the Continental Divide to the upper Cache la Poudre River on the east side of the Continental Divide. We used single nucleotide polymorphisms to characterize population genetic structure in cutthroat trout (Oncorhynchus clarkii) and determine if fish utilize the Grand Ditch as a movement corridor. …

The Natural History And Ecology Of Melanism In Red Wolf And Coyote Populations Of The Southeastern United States – Evidence For Gloger’S Rule, Joseph W. Hinton, Kyla M. West, Daniel J. Sullivan, Jacqueline L. Frair, Michael J. Chamberlain

United States Environmental Protection Agency: Publications

Background: Gloger’s rule postulates that animals should be darker colored in warm and humid regions where dense vegetation and dark environments are common. Although rare in Canis populations, melanism in wolves is more common in North America than other regions globally and is believed to follow Gloger’s rule. In the temperate forests of the southeastern United States, historical records of red wolf (Canis rufus) and coyote (Canis latrans) populations document a consistent presence of melanism. Today, the melanistic phenotype is extinct in red wolves while occurring in coyotes and red wolf-coyote hybrids who occupy the …

Foraging Habitat Selection Of Shrubland Bird Community In Tropical Dry Forest, Anant Deshwal, Steven L. Stephenson, Pooja Panwar, Brett A. Degregorio, Ragupathy Kannan, John D. Willson

United States Geological Survey: Staff Publications

Habitat loss due to increasing anthropogenic disturbance is the major driver for bird population declines across the globe. Within the Eastern Ghats of India, shrubland bird communities are threatened by shrinking of suitable habitats due to increased anthropogenic disturbance and climate change. The development of an effective habitat management strategy is hampered by the absence of data for this bird community. To address this knowledge gap, we examined foraging sites for 14 shrubland bird species, including three declining species, in three study areas representing the shrubland type of forest community in the Eastern Ghats. We recorded microhabitat features within an …

Emplacement Of The Dadeville Complex Of The Southernmost Inner Piedmont Within The 7.5 Min. Cusseta Quadrangle, Chambers County, Alabama: Channel Flow, Klippe Kinematics, Or Orogen Parallel Translation, Timothy Black

Master's Theses

The Appalachian Mountains have a complex geologic history spanning three orogenic periods, the Taconic, the Acadian/Neoacadian, and Alleghanian orogenies. The Inner Piedmont of the Appalachian Mountains within Alabama contains two distinct lithologic complexes, the Dadeville Complex, and the Opelika Complex separated by the Stonewall Line. These complexes were formed during an arc-back arc fringing system during the Taconic orogeny and emplaced and recorded peak metamorphism during the Acadian orogeny.

The Dadeville Complex is an allochthonous arc terrain built on extended Laurentian crust. The mode of transportation and accretion after formation is not well understood, which has implications for the role …

Microbiome Assembly In Thawing Permafrost And Its Feedbacks To Climate, Jessica G. Ernakovich, Robyn A. Barbato, Virginia I. Ritch, Christina Schadel, Rebecca E. Hewitt, Stacey J. Doherty, Emily D. Whalen, Benjamin Abbott, Jiri Barta, Christina Biasi, Chris L. Chabot, Jenni Hultman, Christian Knoblauch, Maggie C. Y. Lau Vetter, Mary-Cathrine Leewis, Susanne Liebner, Rachel Mackelprang, Tullis C. Onstott, Andreas Richter, Ursel M. E. Schutte, Henri M. P. Siljanen, Neslihan Tas, Ina Timling, Tatiana A. Vishnivetskaya, Mark P. Waldrop, Matthias Winkel

Faculty Publications

The physical and chemical changes that accompany permafrost thaw directly influence the microbial communities that mediate the decomposition of formerly frozen organic matter, leading to uncertainty in permafrost–climate feedbacks. Although changes to microbial metabolism and community structure are documented following thaw, the generality of post-thaw assembly patterns across permafrost soils of the world remains uncertain, limiting our ability to predict biogeochemistry and microbial community responses to climate change. Based on our review of the Arctic microbiome, permafrost microbiology, and community ecology, we propose that Assembly Theory provides a framework to better understand thaw-mediated microbiome changes and the implications for community …

Evaluating The Biogeochemical Effects Of Enhanced Rock Weathering At Lawrence University, Katie Mahorney

Lawrence University Honors Projects

On geologic timescales, the weathering of silicate rocks is among the most powerful negative feedbacks controlling atmospheric CO₂. However, this process is too slow to meaningfully impact our current climate crisis. Enhanced Rock Weathering (ERW) is one of the most promising carbon capture strategies to remove anthropogenic carbon from the atmosphere. Models suggest that by crushing silicate rocks such as basalt to increase surface area, the process of rock weathering can be accelerated to sequester enough carbon to be significant on human timescales. At Lawrence University, ERW is being investigated to (1) field test the efficacy of the …

Two New Late Quaternary Avifaunas From The East-Central Great Basin With The Description Of A New Species Of Falco, Steven D. Emslie, Jim I. Mead

Western North American Naturalist

We report 2 new late Quaternary avifaunas from cave deposits in Snake Valley, White Pine County, eastern Nevada, that provide new records of extinct and extant species in the east-central Great Basin. These avifaunas collectively represent at least 24 species, including the most northern inland record of California Condor (Gymnogyps californianus) in western North America and a new species of kestrel (Falco sp.) described herein. Two extralimital living species also were identified—the Harlequin Duck (Histrionicus histrionicus) and Snowy Owl (Bubo scandiacus)—and are the first fossil records of these species in the Great Basin. …

Gigapan® Photogrammetry For Outcrop Description, 3d Modeling, And 3d Printing, Preston Liles, Logan Pearson, Samantha Barnett, Dakota G. Simpson, David B. Fitzpatrick, Erik B. Larson, Maurice Testa

The Compass: Earth Science Journal of Sigma Gamma Epsilon

The collection of 3D information on geological media is fundamental for field geology, however it can be both time consuming and expensive. This report proposes a new method for the collection of 3D information of outcrops using simple to use and inexpensive technology. GigaPan® systems can be used to take high resolution images of outcrops and these images then be either left in 2D for additional description of the outcrop in the lab, or they can be processed in Autodesk 3ds Max® to create realistic 3D models of the outcrops which can then be 3D printed. The collection of this …

Quantitative Relationships Between River And Channel-Belt Planform Patterns, Tian Y. Dong, Timothy A. Goudge

School of Earth, Environmental, & Marine Sciences Faculty Publications

Channel planform patterns arise from internal dynamics of sediment transport and fluid flow in rivers and are affected by external controls such as valley confinement. Understanding whether these channel patterns are preserved in the rock record has critical implications for our ability to constrain past environmental conditions. Rivers are preserved as channel belts, which are one of the most ubiquitous and accessible parts of the sedimentary record, yet the relationship between river and channel-belt planform patterns remains unquantified. We analyzed planform patterns of rivers and channel belts from 30 systems globally. Channel patterns were classified using a graph theory-based metric, …