Digital Commons Network^™

Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson

Master's Theses

It is widely accepted that allelopathy is not only significant, but more or less singular, in the inhibition of understory vegetation in California Eucalyptus globulus (blue gum) plantations. However, there is no published documentation of allelopathy by blue gums against California native species. Here, we present evidence that germination and early seedling growth of five California native species are not inhibited by chemical extracts of blue gum foliage, either at naturally-occurring or artificially concentrated levels. In the greenhouse, seeds were germinated in field-collected soil from mature blue gum plantations and the adjacent native, coastal scrub communities. In petri plates, seeds …

The Plight Of Aspen: Emerging As A Beneficiary Of Wolf Restoration On Yellowstone’S Northern Range, John Klaptosky

Aspen Bibliography

No abstract provided.

Using A Vnir Spectral Library To Model Soil Carbon And Total Nitrogen Content, Nuwan K. Wijewardane

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

n-situ soil sensor systems based on visible and near infrared spectroscopy is not yet been effectively used due to inadequate studies to utilize legacy spectral libraries under the field conditions. The performance of such systems is significantly affected by spectral discrepancies created by sample intactness and library differences. In this study, four objectives were devised to obtain directives to address these issues. The first objective was to calibrate and evaluate VNIR models statistically and computationally (i.e. computing resource requirement), using four modeling techniques namely: Partial least squares regression (PLS), Artificial neural networks (ANN), Random forests (RF) and Support vector regression …

Competition Dynamics Within Communities Of Desert Wildlife At Water Sources, Lucas Keith Hall

Theses and Dissertations

Water is a vital resource for species inhabiting arid and semi-arid regions and can shape the biotic communities that we observe. Because water is considered a limiting resource for many species in desert environments, there is the potential for competitive interactions between species to occur at or around water sources. For this dissertation I tested hypotheses related to resource competition among different species of wildlife in the Great Basin and Mojave Deserts of western Utah. Chapter one evaluated the influence of feral horses (Equus caballus) on patterns of water use by communities of native birds and mammals. Chapter …

Influence Of Release Timing On Survival And Movements Of Translocated Mule Deer (Odocoileus Hemionus) In Utah, David C. Smedley

Theses and Dissertations

Translocation of wildlife has become common practice for wildlife managers charged with management of animals on increasingly modified landscapes. Translocation can be used to reduce population density in the source area, supplement existing populations, reestablish extirpated populations, and establish new populations. Mule deer (Odocoileus hemionus) are a species of great interest to the public in western North America. Although translocations have been used to manage mule deer, very little has been done to document the outcomes of this management practice. The purpose of this research was to evaluate movement, site fidelity, space use, and survival of translocated mule …

Assessing Genetic Variation Of Rocky Mountain Bighorn Sheep At Elk Mountain, Brynn L. Parr, Rebeca L. Juarez, Jonathan A. Jenks

The Prairie Naturalist

The bighorn sheep (Ovis canadensis canadensis) herd occupying the Elk Mountain Region of South Dakota and Wyoming was established in 2001 with 20 individuals. An additional 7 ewes were released in 2004. The population increased to approximately 120 individuals in 2009, but subsequently declined to an estimated 80 individuals. Because of the low population size used to establish the herd and relative isolation of the Elk Mountain Region, potential factors associated with the population decline included reduced genetic diversity. Our objectives were to: 1) assess genetic diversity, 2) measure effective population size (Ne), and 3) compare the genetic diversity of …

Keys To Lichens Of North America, Revised And Expand- Ed. Irwin M. Brodo (Photographs By Sylvia Duran Sharnoff And Stephen Sharnoff; Drawings By Susan Laurie-Bourque)., Caleb A. Morse

The Prairie Naturalist

It would be hard to overestimate the importance of the 2001 publication of Lichens of North America (hereafter LNA) by Irwin Brodo, Silvia Duran Sharnoff, and Stephen Sharnoff (Brodo et al. 2001). Beautifully illustrated, LNA included both an excellent overview to lichenology—including such diverse topics as chemistry, ecology, ethnolichenology, and specimen preparation—and descriptions of more than 800 of the common and charismatic lichens of North Ameri- ca. It is the rare book that provides a good introduction to the discipline, while serving as an essential tool for lichenologists. LNA is frequently cited in journals as an authoritative source on spot …

Varmints And Victims: Predator Control In The Ameri- Can West. Frank Van Nuys., Phil Mastrangelo

The Prairie Naturalist

Having recently retired after 30+ years working in the field of human-wildlife conflicts, including predator conflicts with livestock, I looked forward to reading Varmints and Victims: Predator Control in the American West by Frank Van Nuys. As a wildlife biologist with an interest in the history of wildlife management in North America, I was further intrigued by the subject matter selected by Van Nuys.

In the book’s introduction, Van Nuys explains how the issue of mountain lion (Puma concolor) management in his home state of South Dakota sparked his interest in further exploring the history of predators and their management …

Exploring The Possibility Of Photosynthetic Plasticity In Agave Sensu Lato, John Anthony Huber

Theses and Dissertations

Crassulacean acid metabolism (CAM) provides desert plants with distinct advantages over the C₃ and C₄ photosynthetic pathways in harsh climates where water is scarce. CAM is, however more metabolically costly than C₃ or C₄ photosynthesis, and some plants, such as Mesembryanthemum crystallinum, facultatively utilize CAM when water is abundant, and water conservation unnecessary. In such situations, these plants behave akin to a C₃ plant when photosynthesizing. CAM is divided into four phases, with each phase displaying unique metabolic processes. Certain changes, including changes in the timing of CO₂ fixation, stable carbon isotope ratios, …

Deficient, Adequate And Excess Nitrogen, Phosphorus, And Potassium Growth Curves Established In Hydroponics For Biotic And Abiotic Stress-Interaction Studies In Lettuce, Douglas Keith Jacobson

Theses and Dissertations

Mineral nutrients have marked effects on plant health by providing the building blocks for plant growth, as well as for mitigating abiotic and biotic stress factors, particularly disease development. Even if mineral nutrition field studies are conducted to study pest management, they are at the mercy of complex soil, water, and climatic conditions not amenable to strict experimental control. Therefore, a hydroponic method of growing lettuce was developed and growth curves were established for the macronutrients nitrogen (N), phosphorus (P), and potassium (K). Lettuce plants were grown at varying levels of each nutrient: 2.5, 5, 10, 20, 40, 80, 160, …

Fixed Versus Random Sampling Designs In Small South Dakota Glacial Lakes, Bradley J. Smith, Nathan S. Kruger, Nicholas S. Voss, Brian G. Blackwell

The Prairie Naturalist

Choice of sampling design is fundamental when planning surveys to monitor fisheries resources. However, little is known about the impact that different sampling designs may have on commonly collected fish population metrics used to index relative abundance, size structure, and diversity in small (<200 ha) glacial lakes. To address this issue, we sampled three small glacial lakes in eastern South Dakota with modified fyke nets and gill nets at fixed sites used by South Dakota Game, Fish and Parks and a complement of nets at randomized sites. Catch per unit effort (CPUE), proportional size distribution (PSD), and PSD-preferred (PSD-P) were compared between fixed and random designs for each species and gear by lake while Bray-Curtis distances were calculated between sample designs for each gear type in each lake. Precision of CPUE estimates for routinely indexed species were calculated for both gears used by each sampling design. No consistent bias in calculated population metrics was detected between sampling designs for any species collected with either gear type in the three lakes. Sampling precision of CPUE estimates were low for both gears and study designs; though randomized sites tended to yield lower precision. Power analyses indicated that current levels of sampling effort are insufficient to detect differences in CPUE or PSD/PSD-P between fixed and random sampling designs. In addition to being small, study lakes had relatively homogenous habitat allowing for effective sampling resulting in similar values of CPUE and PSD/PSD-P for both fixed and random study designs, and high assemblage overlap. We conclude that fixed sampling sites provide adequate representation of fish communities in small glacial lakes and are sufficient for monitoring temporal changes in these small, but numerous, systems.

Distribution Of Short-Tailed Shrews (Mammalia: Soricidae: Blarina) In Missouri, Russell S. Pfau, Aaron P. Figueroa

The Prairie Naturalist

Three species of short-tailed shrews (genus Bla- rina) occur throughout the eastern one-half of the United States and southern Canada. B. brevicauda is the most widely distributed, ranging from the Atlantic ocean to the western Great Plains. B. carolinensis occurs throughout the southeastern U.S., and B. hylophaga is found in the southern plains states. The current understanding of the geographic distributions of these species is based primarily on morphol- ogy; size is the primary characteristic used for identifica- tion with B. brevicauda the largest and B. carolinensis the smallest.

The only states in which all three species have been reported …

Notes: Comparisons Of Catch Between Two Bait Types With An Emphasis On Pallid Stur- Geon, Thad W. Huenemann, Kirk D. Steffensen

The Prairie Naturalist

Trotline sampling has been a common practice used by commercial and recreational anglers to target specific fish species (e.g. Ictaluridae and Acipenseridae), while biologists have used them as a management tool to monitor and evaluate fish populations (Graham 1997, Vokoun and Rabeni 1999, Arterburn and Berry 2002, Steffensen et al. 2011). Different trotline configurations have been evaluated to determine which combination of hook type and bait produces higher catch rates for catfish species (Johnson 1987, Arterburn and Berry 2002) but this information is lacking for sturgeon species. For example, Arterburn and Berry (2002) concluded that channel catfish (Ictalurus punctatus) were …

Isotopes From Fecal Material Provides Evidence Of Recent Diet Of Prairie Deer Mice, John W. Doudna, Brent J. Danielson

The Prairie Naturalist

Prairie deer mice are important predators in many agricultural systems, and through their diet they can help to regulate pest insect and weed populations. Our objective was to test whether fecal material is an effective means of detailing the foraging ecology of small mammals. We conducted three studies to evaluate the efficacy of this technique: 1) field-collected fecal material from unknown deer mice from late winter to early spring, 2) fecal material collected in an enclosure with mice fed a mix of C3 and C4 plant seeds, and 3) fecal material from tagged female mice in the field. We detected …

Sage Grouse Groceries: Forb Response To Piñon-Juniper Treatments, Jonathan D. Bates, Kirk W. Davies, April Hulet, Richard F. Miller, Bruce Roundy

Articles

Juniper and piñon coniferous woodlands have increased 2- to 10-fold in nine ecoregions spanning the Intermountain Region of the western United States. Control of piñon-juniper woodlands by mechanical treatments and prescribed fire are commonly applied to recover sagebrush steppe rangelands. Recently, the Sage Grouse Initiative has made conifer removal a major part of its program to reestablish sagebrush habitat for sage grouse (Centrocercus urophasianus) and other species. We analyzed data sets from previous and ongoing studies across the Great Basin characterizing cover response of perennial and annual forbs that are consumed by sage grouse to mechanical, prescribed fire, …

The Hiv-1 Tat Protein Is Monomethylated At Lysine 71 By The Lysine Methyltransferase Kmt7, Ibraheem Ali, Holly Ramage, Daniela Boehm, Lynnette M. A. Dirk, Naoki Sakane, Kazuki Hanada, Sara Pagans, Katrin Kaehlcke, Katherine Aull, Leor Weinberger, Raymond Trievel, Martina Schnoelzer, Masafumi Kamada, Robert L. Houtz, Melanie Ott

Horticulture Faculty Publications

The HIV-1 transactivator protein Tat is a critical regulator of HIV transcription primarily enabling efficient elongation of viral transcripts. Its interactions with RNA and various host factors are regulated by ordered, transient post-translational modifications. Here, we report a novel Tat modification, monomethylation at lysine 71 (K71). We found that Lys-71 monomethylation (K71me) is catalyzed by KMT7, a methyltransferase that also targets lysine 51 (K51) in Tat. Using mass spectrometry, in vitro enzymology, and modification-specific antibodies, we found that KMT7 monomethylates both Lys-71 and Lys-51 in Tat. K71me is important for full Tat transactivation, as KMT7 knockdown impaired the transcriptional activity …

Regeneration: An Overlooked Aspect Of Trait-Based Plant Community Assembly Models, Julie Larson, Jennifer L. Funk

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Despite the disproportionate influence that propagule production, dispersal, seed to seedling recruitment, and vegetative reproduction can have on plant population and community dynamics, progress has been slow in the directed collection of regeneration traits to inform community assembly outcomes.

While seed mass is globally available and linked to growth and reproductive output, there are limits to its explanatory ability. In this essay, we call for expanded efforts to integrate a more diverse set of regeneration traits into community assembly models.

First, we extend an existing community assembly framework to conceptualize regeneration as a series of transitional processes whose outcomes are …

Genetic Engineering And Sustainable Crop Disease Management: Opportunities For Case-By-Case Decision-Making, Paul Vincelli

Plant Pathology Faculty Publications

Genetic engineering (GE) offers an expanding array of strategies for enhancing disease resistance of crop plants in sustainable ways, including the potential for reduced pesticide usage. Certain GE applications involve transgenesis, in some cases creating a metabolic pathway novel to the GE crop. In other cases, only cisgenessis is employed. In yet other cases, engineered genetic changes can be so minimal as to be indistinguishable from natural mutations. Thus, GE crops vary substantially and should be evaluated for risks, benefits, and social considerations on a case-by-case basis. Deployment of GE traits should be with an eye towards long-term sustainability; several …

Preserving Biodiversity For A Climate Change Future: A Resilience Assessment Of Three Bay Area Species--Adenostoma Fasciculatum (Chamise), Arctostaphylos Canescens (Hoary Manzanita), And Arctostaphylos Virgata (Marin Manzanita), Alison S. Pollack

Master's Projects and Capstones

Anthropogenic climate change is an undeniable threat to the future of the natural world and human civilization. These shifts will have profound impacts on vegetation, especially for species endemic to isolated regions or sensitive to climate change factors. However, species resilience can predict success into the next century. Resilience is defined as the ability to withstand climate change factors, whereas vulnerability is defined as susceptibility to climate induced stress or damage.

Chaparral and coastal scrub ecosystems within the Bay Area of California provide a unique context for examining resilience, as many species are adapted to high temperatures, drought, and wildfire—all …

Hands Of The Future, Inc; Junior Nature Club; Living Schoolyards, Zonda K. Bryant

Purdue P-12 Networking Summit & Poster Session

Programs to connect children to nature

A Multiple‐Scale Assessment Of Long‐Term Aspen Persistence And Elevational Range Shifts In The Colorado Front Range, Mario Bretfeld, Scott B. Franklin, Robert K. Peet

Aspen Bibliography

Aspen forests and woodlands are some of the most species‐rich forest communities in the northern hemisphere. Changing climate, altered disturbance regimes, land use, and increased herbivore pressure threaten these forests both in Eurasia and North America. In addition, rapid mortality dubbed “Sudden Aspen Decline” is a concern for aspen's long‐term presence in the western United States, especially Colorado and Utah. Yet it is still unclear whether aspen is persistent or declining at the landscape scale. We assessed aspen persistence at different spatial scales in the Colorado Front Range by resampling 89 plots containing aspen from among 305 vegetation plots sampled …

Non-Specific Phospholipase C1 Affects Silicon Distribution And Mechanical Strength In Stem Nodes Of Rice, Huasheng Cao, Lin Zhuo, Yuan Su, Linxiao Sun, Xuemin Wang

Biology Department Faculty Works

Silicon, the second abundant element in the crust, is beneficial for plant growth, mechanical strength, and stress responses. Here we show that manipulation of the non‐specific phospholipase C1, NPC1, alters silicon content in nodes and husks of rice (Oryza sativa). Silicon content in NPC1‐overexpressing (OE) plants was decreased in nodes but increased in husks compared to wild‐type, whereas RNAi suppression of NPC1 resulted in the opposite changes to those of NPC1‐OE plants. NPC1 from rice hydrolyzed phospholipids and galactolipids to generate diacylglycerol that can be phosphorylated to phosphatidic acid. Phosphatidic acid interacts with Lsi6, a silicon transporter that is expressed …

Herbaceous 2016, Julia I. Chapman, Keith E. Gilland, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

Herbaceous vegetation data collected in 2016 at Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.

Compost Land Management And Soil Carbon Sequestration, Kylene A. Hohman

Senior Honors Projects, 2010-2019

Extensive fossil fuel burning has released carbon dioxide into the atmosphere. Under proper ecological conditions plants convert atmospheric carbon dioxide into stable soil organic matter, a natural and efficient means of mitigating climate change. In the symbiotic relationship between mycorrhizae and plants, mycorrhizae provide plants with essential nutrients in exchange for carbon sugars leaked from the plants. Mycorrhizae convert carbon sugars to an exudate called glomalin, a protein that assists in developing soil aggregates composed of sand, silt, and clay. These aggregates, called humus, store carbon for hundreds of years under healthy ecological conditions. Compost prompts soil microbes to aerobically …

Searching For Potential Binding Partners Of Arabidopsis Β-Amylase2 Using Yeast 2-Hybridization, Megan E. Hines

Senior Honors Projects, 2010-2019

BAM2 is a chloroplast-targeted member of the β-amylase gene family that currently has an unknown function in starch hydrolysis. Previous research indicated that BAM2 did not have significant catalytic activity, but, because the gene is highly conserved and there is a starch-excess phenotype in older plants lacking BAM2, it was hypothesized that BAM2 may instead have a regulatory function. Many regulatory proteins function by interacting with other proteins, so we wanted to test for potential protein binding partners for BAM2 using the yeast two-hybrid system. A plasmid containing the BAM2 gene from Arabidopsis thaliana was co-transformed into Y190-strain yeast ( …

Changes In Oxidative Patterns During Dormancy Break By Warm And Cold Stratification In Seeds Of An Edible Fruit Tree, Dilinuer Shalimu, Jia Sun, Carol C. Baskin, Jerry M. Baskin, Liwei Sun, Yujun Liu

Biology Faculty Publications

The transition from seed dormancy to germination is triggered by environmental factors, and in pomegranate (Punica granatum) seeds higher germination percentages are achieved by warm + cold stratification rather than by cold stratification alone. Our objective was to define the pattern of internal oxidative changes in pomegranate seeds as dormancy was being broken by warm + cold stratification and by cold stratification alone. Embryos isolated from seeds after 1–42 days of warm stratification, after 56 days of warm stratification + 7, 28 or 56 days of cold stratification, and after 1–84 days of cold stratification alone, were used …

A Brief History Of Corn: Looking Back To Move Forward, Jon Derek Pruitt

Doctor of Plant Health Program: Dissertations and Student Research

Maize was domesticated from teosinte in Mexico some 7,000 to 10,000 years ago and quickly spread through the Americas. It has become one of the most important crops at a local and global level. Two types, Northern Flint corn and Southern Dent corns provided the basis of the genetic background of modern maize hybrids. The development of hybrids, first double-cross and later single-cross hybrids, along with a transition to high input farming provided huge yield increases, which have continued to improve with improving technology.

Increase in maize production also caused a rise in Western corn Rootworm (Diabrotica virgifera virgifera …

Using Plant Volatile Traps To Estimate The Diversity Of Natural Enemy Communities In Orchard Ecosystems, Nicholas J. Mills, Vincent P. Jones, Callie C. Baker, Tawnee D. Melton, Shawn A. Steffan, Thomas R. Unruh, David R. Horton, Peter W. Shearer, Kaushalya G. Amarasekare, Eugene R. Milickzy

Agricultural and Environmental Sciences Faculty Research

In this study we used sticky traps baited with plant volatile lures to monitor the biodiversity of natural enemies in orchard ecosystems in the western U.S. We compared the diversity of predator genera from season total trap catches in 37 different orchards (apple, cherry, pear and walnut) over a two-year period (2010−2011) using standardized Hill number biodiversity indices and community similarity profiles. For a subset of 23 of these orchards we were also able to monitor the change in biodiversity of predator genera over the full growing season in the different orchard crops. A total of 37,854 individuals from 31 …

Using Morphometrics To Evaluate Taxonomic Relationships In Eleocharis Tenuis (Cyperaceae), Lane D. Gibbons

Masters Theses, 2010-2019

North America is host to multiple complex taxa, and unresolved relationships in the genus Eleocharis (Cyperaceae). Of noteworthy significance, are lasting taxonomic uncertainties involving plants referable to E. tenuis (var. tenuis, var. verrucosa, and var. pseudoptera) of the E. tenuis species complex. Morphology of E. tenuis is traditionally recognized as being widely variable, and intermediate among taxa along a broad geographic gradient. Cytological and morphometric data however, indicate that the varieties of E. tenuis are unique in cytology, and are consistently delimited by five morphological characters. Furthermore, this study shows that cytological data correlates with unique morphological …

Photosynthetic Characterization Of Invasive Plant Diversity In Los Angeles County From 1830-2010, Lauren E. Pangburn, Erich Eberts, Victor Carmona-Galindo

Honors Thesis

The increase in atmospheric CO₂ levels due to climate change may greatly impact invasive plant species, which are non-native organisms that spread unchecked in space and negatively impact native organisms. The success of these invasives may be related to specific traits, such as their photosynthetic pathway. We acquired the specimen information for invasive species registered in the Consortium for California Herbaria of the University of California Berkeley to evaluate the community dynamics of 1,000 invasive species in Los Angeles County. We found that both diversity and richness of invasive plant species has increased over a period of 180 years. …