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Propagation Methods For Growing Spartina Alterniflora For Salt Marsh Restoration, Samantha Walker

Senior Honors Projects

Salt marsh ecosystems can be found along the east coast of the United States, but are now disappearing due to human development and sea level rise. Salt marshes provide countless ecosystem services including shoreline protection from storms and flooding, nutrient removal, habitat for fish, birds and other wildlife, and provide some of the most beautiful areas for hunting, fishing and recreational activities. In order to protect salt marshes and restore the large portion of them that have been damaged, it is important to focus on the vegetation that help salt marshes function. Spartina alterniflora, smooth cordgrass, is a critical …

Tree Islands Of Fertility Structure Bacterial Community Assembly And Functional Genes Contributing To Ecosystem Processes, Tayte Paul Campbell

Theses and Dissertations

In arid and semi-arid ecosystems, dominant tree species create dramatic mosaics of plant islands of fertility and relatively barren plant interspaces that exert immense pressure on ecosystem processes and offers an ideal opportunity to explore the impact of bacterial communities. We evaluated potential links between soil respiration and N mineralization, and community co-occurrence networks and predicted gene function across three tree island microsites (i.e., beneath tree canopies, at the canopy edge, and in interspaces) in a replicated field experiment in thirty-eight woodlands sites in the Great Basin Desert in UT, USA. Additionally, we potentially intensified the effects of tree islands …

Physiological And Nutritional Characterization Of High Yield Soybean, Ryan John Van Roekel

Graduate Theses and Dissertations

Soybean [Glycine max (L.) Merr.] grain yields greater than three times the national average have been reported in yield contests. Characterization of soybean in a maximum yield environment is necessary to provide empirical data to support those yield claims and to provide an understanding of the physiological processes at that yield level. From 2011 to 2013, research characterized biomass and N accumulation rates, radiation use efficiency (RUE), leaf N dynamics, the rate of harvest index increase (dry matter allocation coefficient, DMAC), seedfill period (SFP), and grain yield components from Mr. Kip Cullers' contest fields and in small plots at the …

Use Of Fluridone For Control Of Palmer Amaranth (Amaranthus Palmeri) In Cotton (Gossypium Hirsutum) And On Ditchbanks, Zachary Thornton Hill

Graduate Theses and Dissertations

Since 2006, glyphosate-resistant Palmer amaranth has been considered the most problematic weed in agronomic crops across the Midsouth. As a result of glyphosate resistance, producers began to again utilize a diverse herbicide program for management of this weed, which consists of several soil-residual herbicides most notably diuron, fluometuron, fomesafen, and metolachlor. Fluridone inhibits phytoene desaturase in plants, and is unique in that its mechanism of action (MOA) is not currently registered for use in cotton. Studies were conducted to determine the length of residual that fluridone provides in controlling Palmer amaranth in Arkansas glyphosate- and glufosinate-resistant cotton programs and along …

Restoration Strategies To Migrate Shrub Encroachment Into Coastal Prairies, Erick Mark Verderber

Theses and Dissertations - UTB/UTPA

Shrub encroachment into grasslands is a phenomenon facilitated by fire suppression, climate warming, and overgrazing of grasses by cattle, and if left unmanaged, can alter ecosystem structure and function. In this study, I compare the effectiveness and cost/benefit of various restoration strategies (prescribed fire, mechanical, and chemical) used singly and in different combinations at decreasing two shrubs, honey mesquite (Prosopis glandulosa Torr.) and huisache (Acacia farnesiana (L.) Willd.), and promoting growth and survival of gulf cordgrass (Spartina spartinae (Trin.) Merr. ex Hitchc.), the dominant coastal prairie grass within the Laguna Atascosa National Wildlife Refuge-Bahia Grande Unit in deep south Texas. …

Species Delimitation And Phylogenetic Relationships Of The Wild Yams (Dioscorea) Native To Eastern North America, Tori A. Collins

Honors Theses

Most taxonomic treatments currently recognize two to three species of native yams in eastern North America: Dioscorea villosa, D. floridana, and sometimes D. quaternata, a segregate of D. villosa. Earlier authors (e.g., J. K. Small) had recognized as many as five species (with D. hirticaulis and D. glauca also as segregates of D. villosa). Key morphological features in distinguishing these putative species are rhizome morphology (long and cord-like vs. thick and contorted), number of first leaves (1–3 vs. 4–7), and habitat (sandy, rocky, swampy). Unfortunately, these critical features are rarely collected and preserved on herbarium …

A New Species Of Euphorbia Subgenus Chamaesyce Section Alectoroctonum (Euphorbiaceae) From Limestone Hills Of Wayne County, Mississippi, Andrew C. Fennell

Honors Theses

As part of a project to document the vascular flora of Wayne County, Mississippi, an unusual Euphorbia, which keys to the Euphorbia corollata complex, was encountered in mature hardwood forests in limestone regions. Unlike typical E. corollata and E. pubentissima, these individuals have long petioles (0.4–1.2 cm), oval to ovate leaves, short stature, small cyathia, small seeds, and a different phenology. In order to test species boundaries, morphological character differences were explored using principal component analysis (PCA), and additional characters were gathered from plastid (rpL16) and nuclear (ITS) DNA data of the unusual individuals as well …

Mapping Regional Inundation With Spaceborne L-Band Sar, Bruce Chapman, Kyle Macdonald, Masanobu Shimada, Ake Rosenqvist, Ronny Schroeder, Laura Hess

Publications and Research

Shortly after the launch of ALOS PALSAR L-band SAR by the Japan Space Exploration Agency (JAXA), a program to develop an Earth Science Data Record (ESDR) for inundated wetlands was funded by NASA. Using established methodologies, extensive multi-temporal L-band ALOS ScanSAR data acquired bi-monthly by the PALSAR instrument onboard ALOS were used to classify the inundation state for South America for delivery as a component of this Inundated Wetlands ESDR (IW-ESDR) and in collaboration with JAXA’s ALOS Kyoto and Carbon Initiative science programme. We describe these methodologies and the final classification of the inundation state, then compared this with results …

Multi-Level Effects Of Low Dose Rate Ionizing Radiation On Southern Toad, Anaxyrus [Bufo] Terrestris, Karolina Stark, David E. Scott, Olga Tsyusko, Daniel P. Coughlin, Thomas G. Hinton

Plant and Soil Sciences Faculty Publications

Despite their potential vulnerability to contaminants from exposure at multiple life stages, amphibians are one of the least studied groups of vertebrates in ecotoxicology, and research on radiation effects in amphibians is scarce. We used multiple endpoints to assess the radiosensitivity of the southern toad (Anaxyrus [Bufo] terrestris) during its pre-terrestrial stages of development -embryonic, larval, and metamorphic. Toads were exposed, from several hours after oviposition through metamorphosis (up to 77 days later), to four low dose rates of ¹³⁷Cs at 0.13, 2.4, 21, and 222 mGy d^-1, resulting in total doses up to 15.8 …

Field Evaluation Of A Push-Pull System To Reduce Malaria Transmission, David J. Menger, Philemon Omusula, Maarten Holdinga, Tobias Homan, Ana S. Carreira, Patrice Vandendaele, Jean Luc Derycke, Collins K. Mweresa, Wolfgang Richard Mukabana, Joop J.A. Van Loon, Willem Takken

All Peer-Reviewed Publications

Malaria continues to place a disease burden on millions of people throughout the tropics, especially in sub-Saharan Africa. Although efforts to control mosquito populations and reduce human-vector contact, such as long-lasting insecticidal nets and indoor residual spraying, have led to significant decreases in malaria incidence, further progress is now threatened by the widespread development of physiological and behavioural insecticide-resistance as well as changes in the composition of vector populations. A mosquito-directed push-pull system based on the simultaneous use of attractive and repellent volatiles offers a complementary tool to existing vector-control methods. In this study, the combination of a trap baited …

A New Sustainable Environmental Education Toolbox For Botanic Gardens, Parks & Arboreta, John J. Pipoly Iii

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

No abstract provided.

Hyperdominance In Amazonian Forest Carbon Cycling, Sophie Fauset, Michelle O. Johnson, Manuel Gloor, Timothy R. Baker, Abel Monteagudo M., Roel J. W. Brienen, Ted R. Feldpausch, Gabriela Lopez-Gonzalez, Yadvinder Malhi, Hans Ter Steege, Nigel C. A. Pitman, Christopher Baraloto, Julien Engel, Pascal Petronelli, Ana Andrade, Jose Luis C. Camargo, Susan G. W. Laurance, William F. Laurance, Jerome Chave, Elodie Allie, Percy Nunez Vargas, John W. Terborgh, Kalle Ruokolainen, Marcos Silveira, Gerardo A. Aymard C., Luzmila Arroyo, Damien Bonal, Hirma Ramirez-Angulo, Alejandro Araujo-Murakami, David Neill, Bruno Herault, Aurelie Dourdain, Armando Torres-Lezama, Beatriz S. Marimon, Rafael P. Salomao, James A. Comiskey, Maxime Rejou-Mechain, Marisol Toledo, Juan Carlos Licona, Alfred Alarcon, Adriana Prieto, Agustin Rudas, Peter J. Van Der Meer, Timothy J. Killeen, Ben-Hur Marimon Jr., Lourens Poorter, Rene G. A. Boot, Basil Stergios, Emilio Vilanova Torre, Flavia R. C. Costa, Carolina Levis, Juliana Schietti, Priscila Souza, Nikee Groot, Eric Arets, Victor Chama Moscoso, Wendeson Castro, Euridice N. Honorio Coronado, Marielos Pena-Claros, Clement Stahl, Jorcely Barroso, Joey Talbot, Ima Celia Guimaraes Vieira, Geertje Van Der Heijden, Raquel Thomas, Vincent A. Vos, Everton C. Almeida, Esteban Alvarez Davila, Luiz E. O. C. Aragao, Terry L. Erwin, Paulo S. Morandi, Edmar Almeida De Oliveira, Marco B. X. Valadao, Roderick J. Zagt, Peter Van Der Hout, Patricia Alvarez Loayza, John J. Pipoly Iii, Ophelia Wang, Miguel Alexiades, Carlos E. Ceron, Isau Huamantupa-Chuquimaco, Anthony Di Fiore, Julie Peacock, Nadir C. Pallqui Camacho, Ricardo K. Umetsu, Plinio Barbosa De Camargo, Robyn J. Burnham, Rafael Herrera, Carlos A. Quesada, Juliana Stropp, Simone A. Vieira, Marc Steininger, Carlos Reynel Rodriguez, Zorayda Restrepo, Adriane Esquivel Muelbert, Simon L. Lewis, Georgia C. Pickavance, Oliver L. Phillips

Marine & Environmental Sciences Faculty Articles

While Amazonian forests are extraordinarily diverse, the abundance of trees is skewed strongly towards relatively few ‘hyperdominant’ species. In addition to their diversity, Amazonian trees are a key component of the global carbon cycle, assimilating and storing more carbon than any other ecosystem on Earth. Here we ask, using a unique data set of 530 forest plots, if the functions of storing and producing woody carbon are concentrated in a small number of tree species, whether the most abundant species also dominate carbon cycling, and whether dominant species are characterized by specific functional traits. We find that dominance of forest …

How Does The Exploitation And Degradation Of Finite Natural Resources By Industrial Oil Producers Effect Our Future Planetary Environment?, Zachary J. King Mr.

Symposium of Student Scholars

Zachary King

Dr. Tu

26 March 2015

GEOG 3700

Abstract

The purpose of this presentation is to communicate content of the reports given by credible institution on the degradation and exploitation of finite natural resources by corporate institutions, for short term financial gain, and how it will effect the future planetary environment. Methods used in obtaining this research range from point source observation directly from oil spills in the Gulf or pipe leaks in the Mid-West, to analytical and numerical data quantifications gathered over a period of two decades. This presentation encompasses a wide scope of information concerning the way …

Fitness Parameters In Malosma Laurina Seedlings Growing Near And Away From Invasive Brassica Nigra, Natalie M. Aguirre, Agustin Vargas, Phoebe Shin

Featured Research

In this study we aim to assess the photosynthetic rate of native Malosma laurina (M. laurina) seedling, in comparison to M. laurina seedlings growing amongst several hundred B. nigra invasive plants. We predicted that there will be a difference in the stomatal conductance of each population. We measured photosynthetically active radiation (PAR), seedling height, and stomatal conductance of two isolated populations of M. laurina seedlings. One population grows near B. nigra, an invasive specie, and the other only grows amongst native plants. We found that M. laurina seedlings growing near weeds …

Effects Of Drought On Malosma Laurina Leaves, Suk Ho (Josh) Chang, Jingyi Chen, Sarah B. Nelson

Featured Research

Drought induced deformations in the chaparral plant Malosma laurina were observed following the lack of water availability during the years of 2013 and 2014. We hypothesized that the middle leaves grown during the drought would have the lowest productivity, the top post-drought leaves would have the highest productivity, and the bottom pre-drought leaves would have an intermediate level of productivity. We used a sample size of n = 6, representing 6 unique M. laurina plants. To obtain our data, we used the LI-6400 gas exchange system. In our comparisons of photosynthetic rate, stomatal conductance, and photosynthetic quenching of the top, …

Correlation Between Hydration And Reflectance Of Yellow Petals On Encelia Californica, Jayci M. Givens, Kaylee A. Nussbaum, Caitlin R. Kawata

Featured Research

It is known that the NDVI can be used as a measure of hydration in plants because of the variation in pigments due to xanthophyll cycling (Schmitz et al., 2013). Flower petals can also exhibit variations in petal reflectance invisible to the naked eye (Fam & Espinoza, 2013). It was hypothesized that overall hydration levels of a plant would correlate to a difference in the pigments produced for petal color, and thus differences in hydration levels would correlate to differences in petal reflectance. To test this hypothesis, three flowers and two stems were collected from ten different E. californica plants, …

Effects Of High Light Exposure On Photosynthetic Rate And Fluorescence Of Eucrypta Chrysanthemifolia, Alec Flores, Gina Gilderman, Hannah Dario

Featured Research

In this experiment, we examined how a partial shade plant, Eucrypta chrysanthemifolia, found in the Santa Monica Mountains, responded to predictive models of higher light intensities created bydrought. We hypothesized that, with higher levels of light, Eucrypta chrysanthemifolia would respond with a decreased photosynthetic rate, light-adapted, and dark-adapted fluorescence. This was performed by comparing control plants grown in an artificial shade environment to plants exposed to a series of high light intensity treatments. These partial shade plants were found on Piuma Trail in the Santa Monica Mountains. Our data supported our null hypothesis, indicating the photosynthetic rates and light-adapted …

Seedling Resprouts Of Adenostoma Fasciculatum Between Wildfire Cycles Are Promoted By Environmental Conditions That Mimic Fire-Like Environments, Lexe Evans, Teal Speece, Stephen D. Davis

Featured Research

The Santa Monica Mountains represent one of the largest Mediterranean-type environments in the world. With sustained summer droughts, this ecosystem has become prone to frequent wildfires, a phenomenon that has affected the area with regularity (approximately 21 years apart). Naturally, this cycle of wildfires has had a great effect upon the mortality and survival of the diverse chaparral varieties that inhabit the Santa Monica Mountain region. This includes the Adenostoma fasciculatum (chamise), which is the most commonly-found form of chaparral shrub in California. (Redfeldt & Davis, 1996) This species of chaparral is particularly well-adapted to survival in a climate that …

Difference In Chaparral Species Population On The North And South Aspect On Pepperdine University Campus, Alexandra N. Lozano, Drew N. Rasmussen, Ashlyn L. Rawls

Featured Research

In this experiment, we analyzed the difference in population frequencies of chaparral plants along the north and south aspect of a slope on Pepperdine University campus in the Santa Monica Mountains in Malibu, CA. We began the experiment by hypothesizing the south aspect would receive the most sunlight, and thus would hold the most amount of plants. By using the Point Quarter Sampling Method, we were able to determine if our hypothesis was correct. After analyzing our data, we found no significant difference between the north and south aspect in terms on frequency. During our experiment we also measured the …

Possible Fungal Infection Leading To Malosma Laurina Dieback, Gabriella N. Palmeri, Braden S. Olsen, Kaitlyn E. Sauer, Stephen D. Davis

Featured Research

There is a significant and apparent dieback of Malosma laurina in the Santa Monica Mountains, some which is found near Pepperdine University. Other areas near Pepperdine show a flourishing growth of M. laurina and our objective was to determine why this difference in M. laurina health exists. We initially hypothesized that in addition to water stress, the unhealthy M. laurina was effected by a pathogen. Under further inspection, the unhealthy plants contained hyphae in some of their xylem vessels, while the healthy ones did not. We sought to determine whether the existence of hyphae in the unhealthy plant’s xylem affected …

Morphological Changes In Malosma Laurina Due To Prolonged Drought In The Santa Monica Mountains, Grace S. M. Bae, Majie C. Foster, Maryelizabeth S. Stein, Mariah K. Taylor

Featured Research

Observations of Malosma laurina seedlings in Sycamore Canyon, Malibu, CA, exhibit abnormally small and wrinkled leaves. We propose that the prolonged drought in California’s Santa Monica Mountains has lead to physical malformations indicative of water strain in the leaves of M. laurina plants. In this experiment, we tested water relations of six M. laurina plants found on Pepperdine University’s Malibu campus showing similar leaf patterns to those found in Sycamore Canyon. Six M. laurina plants devoid of the abnormal leaf growth patterns functioned as our control group. Stomatal conductance, water potential, and leaf mass to area data was gathered using …

Gata-Dependent Glutaminolysis Drives Appressorium Formation In Magnaporthe Oryzae By Suppressing Tor Inhibition Of Camp/Pka Signaling, Margarita Marroquin-Guzman, Richard A. Wilson

Department of Plant Pathology: Faculty Publications

Fungal plant pathogens are persistent and global food security threats. To invade their hosts they often form highly specialized infection structures, known as appressoria. The cAMP/ PKA- and MAP kinase-signaling cascades have been functionally delineated as positive-acting pathways required for appressorium development. Negative-acting regulatory pathways that block appressorial development are not known. Here, we present the first detailed evidence that the conserved Target of Rapamycin (TOR) signaling pathway is a powerful inhibitor of appressorium formation by the rice blast fungus Magnaporthe oryzae. We determined TOR signaling was activated in an M. oryzae mutant strain lacking a functional copy of …

Preliminary Phylogenetic Analysis Of The Andean Clade And The Placement Of New Colombian Blueberries (Ericaceae, Vaccinieae), Paola Pedraza-Peñalosa, Nelson R. Salinas, Anne Lucy S. Virnig, Ward C. Wheeler

Publications and Research

The blueberry tribe Vaccinieae (Ericaceae) is particularly diverse in South America and underwent extensive radiation in Colombia where many endemics occur. Recent fi eldwork in Colombia has resulted in valuable additions to the phylogeny and as well in the discovery of morphologically noteworthy new species that need to be phylogenetically placed before being named. Th is is particularly important, as the monophyly of many of the studied genera have not been confi rmed. In order to advance our understanding of the relationships within neotropical Vaccinieae and advice the taxonomy of the new blueberry relatives, here we present the most comprehensive …

The Effects Of Salinity On The Photosynthetic Rate Of Limonium Californicum, Adriana J. Borges, Elizabeth S. Chau, Justine M. Mckitrick

Featured Research

Halophytic plants, unlike most plants, are able to survive in stressful saline environments. Halophytes possess adaptations to osmoregulate, which gives them a competitive edge in saline environments such as coastal salt marshes. Our group analyzed the responses to salinity of the halophytic plant, Limonium californicum, which is present in California’s coastal salt marshes. We hypothesized that the photosynthetic rate of the Limonium californicum plants would decrease with increasing saline water treatments. In order to test this hypothesis, we watered L. californicum plants with solutions of varying salinity over the course of four days. We measured the photosynthetic rates using …

Correlation Between Hydration And Reflectance Of Yellow Petals On Encelia Californica, Jayci M. Givens, Kaylee A. Nussbaum, Caitin R. Kawata

Featured Research

It is known that the NDVI can be used as a measure of hydration in plants because of the variation in pigments due to xanthophyll cycling (Schmitz et al., 2013). Flower petals can also exhibit variations in petal reflectance invisible to the naked eye (Fam & Espinoza, 2013). It was hypothesized that overall hydration levels of a plant would correlate to a difference in the pigments produced for petal color, and thus differences in hydration levels would correlate to differences in petal reflectance. To test this hypothesis, three flowers and two stems were collected from ten different E. californica plants, …

Producing Quality Barley For The Malting Industry, Haley H. Oser Dph

Doctor of Plant Health Program: Dissertations and Student Research

The University of Nebraska – Lincoln Doctor of Plant Health program requires each student to fulfill a professional internship over the last summer of the program. For my internship, I worked as a Barley Scientist Intern for MillerCoors and Golden Malting in Golden, Colorado. During this internship I gained a fundamental understanding of malting barley production with a significant emphasis on grain quality. Barley produced for malting must fulfill strict industry quality standards before it is accepted by the head maltsters. These quality standards include: a high germination rate, low moisture content, protein content within an acceptable range and the …

The Effect Of Red Maple Leaf Toxicosis On Reduced Glutathione Levels In Equine Erythrocytes In Vitro, Madeline A. Rohl

Undergraduate Honors Thesis Projects

Red maple leaf toxicosis is an equine blood disorder resulting from the consumption of wilted red maple (Acer rubrum L.) leaves by horses. Compounds within the leaves of red maple have oxidative effects on equine erythrocytes and can cause hemolysis of erythrocytes, the conversion of hemoglobin to methemoglobin, and the production of Heinz bodies. Reduced glutathione is important in the protection of equine erythrocytes from these oxidative events; however, in the presence of red maple toxin, glutathione is rapidly oxidized and is unavailable. The objective of this study is to determine whether the presence of vitamin C alters levels …

Cultivating An Undergraduate Mentoring Research Environment By Characterizing The Population Genetics, Reproduction Biology, And Native Distribution Of A Putative Keystone Species, Agave Utahensis (Utah Agave), In The Mojave Desert And Colorado Plateau, J. Ryan Stewart

Journal of Undergraduate Research

• Evaluation of how well the academic objectives of the proposal were met
• Evaluation of the mentoring environment
• List of students who participated and what academic deliverables they have produced or it is anticipated they will produce
• Description of the results/findings of the project
• Description of how the budget was spent

Signal Regulators Of Systemic Acquired Resistance, Qing-Ming Gao, Shifeng Zhu, Pradeep Kachroo, Aardra Kachroo

Plant Pathology Faculty Publications

Salicylic acid (SA) is an important phytohormone that plays a vital role in a number of physiological responses, including plant defense. The last two decades have witnessed a number of breakthroughs related to biosynthesis, transport, perception and signaling mediated by SA. These findings demonstrate that SA plays a crictical role in both local and systemic defense responses. Systemic acquired resistance (SAR) is one such SA-dependent response. SAR is a long distance signaling mechanism that provides broad spectrum and long-lasting resistance to secondary infections throughout the plant. This unique feature makes SAR a highly desirable trait in crop production. This review …

The Ongoing Search For The Molecular Basis Of Plant Osmosensing, Elizabeth S. Haswell, Paul E. Verslues

Biology Faculty Research

Introduction: Cell viability and metabolism depend on cytoplasmic water and solute content, and organisms have evolved mechanisms to sense changes in cell water content, solute concentrations, cell volume, and/or turgor. This Perspective addresses the response to osmotic challenge in land plants and describes their special dependence on cellular water status for growth and development. Understanding how plants cope with water limitation may allow us to mitigate the agricultural effects of drought, a critical limitation on global crop productivity that is likely to increase in severity as the climate changes (Long and Ort, 2010). The signaling pathways by which plants respond …