Ecology and Evolutionary Biology Commons^™

Effects Of Hemiparasites In Grassland Restorations Are Not Universal, Anna Marie Scheidel, Victoria Borowicz

Faculty Publications – Biological Sciences

Root hemiparasites infiltrate the vascular tissue of host roots to acquire water and nutrients, which often reduces host growth. Hemiparasites are postulated to be keystone species in grassland communities if they suppress dominant species and increase plant community biodiversity, and ecosystem engineers if they increase nutrient accessibility for surrounding species. We examined keystone effects by evaluating species richness and evenness in 1 m2 plots in a recent prairie restoration where Castilleja sessiliflora was naturally present or absent, and in a longer-established prairie restoration with or without Pedicularis canadensis. We examined ecosystem engineer effects by determining nitrate and phosphate concentrations …

Using Leaf Spectra To Elucidate The Taxonomy And Ecology Of Living And Dried Plants, Natalia L. Quinteros Casaverde

Dissertations, Theses, and Capstone Projects

Identifying plants and understanding of changes in plant communities are crucial to the conservation and management of nature. The shortwave spectral reflectance of leaves is a promising tool for rapidly identifying species at different taxonomic ranks and predicting important plant functional traits. However, the spectral reflectance of leaves changes in response to biotic and abiotic conditions.

The aim of this dissertation is to investigate the potential of shortwave spectral reflectance to investigate (Chapter 1) how its variation affects the accuracy of methods used to predict plant taxonomies and what environmental factors most influence biophysically predicted traits, (Chapter 2) what are …

Toward Improved Global Food Security: Uncovering How Tomatoes Fight Root-Knot Nematodes, Chingyan H. Huang

The Journal of Purdue Undergraduate Research

No abstract provided.

Exploring The Evolution Of Callose Synthase In Green Plants, Giovanna Durante

The Journal of Purdue Undergraduate Research

No abstract provided.

Aspen Recovery In Northern Yellowstone: A Comment On Brice Et Al. (2021), Luke E. Painter, Robert L. Beschta, William J. Ripple

Aspen Bibliography

Aspen sapling recruitment increased as browsing by elk decreased, following the 1995–96 reintroduction of wolves in Yellowstone National Park. We address claims by Brice et al. (2021) that previous studies exaggerated recent aspen recovery. We conclude that their results actually supported previous work showing a trophic cascade benefiting aspen.

Aspen And Spruce Densities Affect Tree Size, Future Stand Volume, And Aboveground Carbon Following Precommercial Thinning, Philip G. Comeau, Mike Bokalo

Aspen Bibliography

Data collected over a 30-year period from an experiment replicated across 21 locations in western Canada are used to explore the effects of precommercial thinning of trembling aspen to a range of densities in combination with three initial white spruce densities on tree growth and stand dynamics. Increasing differentiation amongst the 15 treatments was observed with age after thinning for both spruce and aspen responses. Spruce height and diameter declined with increasing aspen density. At age 10 spruce diameter with no aspen was 1.5× that of spruce in unthinned while it was 2.6× that of spruce in unthinned at age …

Tracing The Maternal Line In Glacial-Interglacial Migrations Of Populus Tremuloides: Finding Trees For Future Sustainable Forests By Searching In The Past, Luke R. Tembrock, Frida A. Zink, Guozhe Zhang, Andrea Schuhmann, Cuihua Gu, Zhiqiang Wu

Aspen Bibliography

Maintaining and planting sustainable forests is fundamental in perpetuating the essential functions of these ecosystems. A central aspect of managing forests for future resilience is the consideration of past migration and evolution of trees using genetic and genomic data to ensure that functionally appropriate diversity is conserved and utilized. In our study, we generated and compared genetic and genomic data from the plastome to better understand phylogeography and molecular evolution in the tree species Populus tremuloides (aspen). With these analyses, we found evidence of divergence and migration between northern and southern sites. Additionally, evidence of deep incomplete plastome sorting across …

The Long-Term Effects Of Prescribed Fire On Floral Abundance And Bumble Bee Abundance In Mixed-Oak Forests Of Southeastern Ohio, Moses Shafer

Theses, Dissertations and Capstones

Pollinators are declining due to climate change and habitat loss driven by agriculture and urbanization. In fire-adapted ecosystems, fire promotes the biodiversity of plants by creating space, reducing competition, and increasing light and nutrient availability. However, little is known regarding the effects of fire on floral abundance of plants used by Bombus. The overall goal of this project was to assess the long-term effects of fire on floral abundance and Bombus abundance. Our specific questions were: (1) How does fire frequency influence floral abundance?, (2) How does fire frequency influence floral abundance of species specifically utilized by bumble bees?, …

Factors Determining The Success Of Recently Planted Spartina Alterniflora On A Living Shoreline In Jamaica Bay, Ny, Abby K. Bressette, Shakira Thomas, Brett F. Branco

Environmental Studies Publications

Natural and nature-based features have been implemented throughout New York City to provide habitat and reduce flooding, erosion, and pollution. The West Pond Living Shoreline in Jamaica Bay, NY was designed with organic breakwaters and native marsh plants, including S. alterniflora. Post-construction monitoring in 2021 found that percent coverage of S. alterniflora was lower than expected. To inform future management, we studied the effect of elevation, planting method, and shoreline energy exposure on the percent cover, average stem height, and average stem density of S. alterniflora. Elevation and plant growth data were collected within 8 one sq. meter quadrats at …

Ms Environmental Biology Capstone Project, Sarah Luper

Regis University Student Publications (comprehensive collection)

Recreational trails and the presence of invasive species such as Bromus inermis can both disturb grassland community composition. Trails can act as dispersal corridors for plant material, but can also be a source of trampling and compaction. Invasive grasses like Bromus inermis can easily establish in grasslands and decrease species richness by increasing competition. Understanding these effects, this study aims to understand how both the presence of recreational trails as well as the presence of Bromus inermis affect species richness and overall community composition at Two Ponds National Wildlife Refuge. Belt transect sampling took place in fall 2019 and again …

Environmental Biology Masters Capstone, Antonio Gonzalez-Pita

Regis University Student Publications (comprehensive collection)

Human wildlife interactions (HWI) pose a complex challenge for wildlife managers. Human encroachment into wildlife habitat and the growing number of outdoor recreationists are increasing the frequency of contact and conflict, especially in regions such as the Front Range of Colorado. Geographic information systems (GIS), which use a combination of remote sensing and environmental survey data, allow for predictive spatial analyses of where human wildlife interactions are likely to occur. I used publicly reported observations of moose to create spatial predictive maps in a species distribution model framework. Slope and elevation were shown to be the strongest predictors of HWI, …

Invasion Ecology Of Alternanthera Philoxeroides, Cyperus Blepharoleptos, Panicum Repens, And Triadica Sebifera, Samuel A. Schmid, Adrián Lázaro-Lobo, Cory M. Shoemaker, Andrew Sample, Mackenzie Cade, Gary N. Ervin, Gray Turnage

GRI Publications

Several invasion ecology hypotheses explain patterns of invasion, but these effects are often complex and multifaceted. Within the study of aquatic invasive species, small aquatic ecosystems are often neglected, despite them representing most global freshwater bodies. This study uses community composition and environmental and geographic factors to explain the occurrence of invasive species in small lakes in the southeastern United States. Specifically, this study predicted that several ecosystem factors would predict the probability of occurrence of invasive species of the lakes studied. Four of the most common invasive species were selected as the focus of this study: Alternanthera philoxeroides, Cyperus …

Monarch Butterfly (Danaus Plexippus) Oviposition Preferences And A Survey Of Fungal Pathogens On Native Milkweeds (Asclepias) Of The Northern Great Plains, Grace Damiano

Electronic Theses and Dissertations

North American monarch butterfly (Danaus plexippus) populations are experiencing significant declines due to habitat loss caused by land use changes. Much of the American Midwest where milkweed, the only host plant of the monarch butterfly, was once much more abundant has been converted to a predominantly agricultural landscape. There are nineteen species of milkweed native to the northern Great Plains region occupied by South Dakota, North Dakota, and Minnesota. Some of these milkweed species may be preferable to monarch butterflies for different reasons, including morphological factors such as stem length, species-level chemical factors, and temporal factors. As monarch …

Aspen Forest Condition Assessment And Restoration Guidance, Paul C. Rogers

Aspen Bibliography

This preliminary report is the first installment of an ongoing aspen assessment at Bryce Canyon National Park (BCNP). Over a 1.5-year period beginning in 2021, I assembled available BCNP and conducted a preliminary field survey to gain a better understanding of the quaking aspen (Populus tremuloides) resource within the Park. Findings suggest a long history of vegetation mapping with mixed results in terms of highlighting aspen presence a notable species of overall low coverage as well as aspen importance, at BCNP. In brief, though this species has limited presence, it is of high biodiversity conservation value. According to …

The Genetic Diversity Of An Endangered Buttercup, Ranunculus Triternatus, Ryan Garcia

All Graduate Projects

Ranunculus triternatus, a rare endemic species of the Columbia River Gorge, faces conservation challenges due to its limited range and fragmented populations. This study assesses the genetic diversity of R. triternatus and compares it with its widespread congener, Ranunculus glaberrimus, using inter-primer binding site (iPBS) markers. Genetic data from 80 individuals across eight populations were analyzed using Nei’s genetic diversity, Shannon’s diversity index, and AMOVA. Results showed R. triternatus had higher genetic diversity than western populations of R. glaberrimus, with eastern populations of R. glaberrimus displaying greater diversity than western ones. PCA, UPGMA, and STRUCTURE analysis revealed …

Taxonomic Status, Distribution And Conservation Of The Critically Endangered Plant Psychotria Angustata (Rubiaceae), Walter Simbaña, Alan Tye, Timothy J. Motley, Uno Eliasson

Biological Sciences Faculty Publications

Simbaña, W.; A. Tye, T. J. Motley & U. Eliasson. 2024. Taxonomic status, distribution and conservation of the Critically Endangered plant Psychotria angustata (Rubiaceae), endemic to Floreana Island, Galapagos. Darwiniana, nueva serie 12(2): 204-219.

Two species of Psychotria have been recognised in the Galapagos Islands, both understorey shrubs endemic to the archipelago: P. rufipes Hook.f. occurs on seven islands, including Floreana, while P. angustata Andersson is endemic to Floreana. Since their mid-19th century discovery, the taxonomic and ecological status of these species has been uncertain. To clarify this, we examined historical specimens and numerous recent collections of both species, and …

Pcb Remediation In Transitional Floodplain Forests Along The Housatonic River, Soleil Laurin

Scripps Senior Theses

Human development affects natural environments in more ways than climate change, from the introduction of nonnative species and deforestation to pollution and urbanization. This is a case study examining the effects of PCB remediation on transitional floodplain forest along the Housatonic River in Western Massachusetts. The Housatonic River had previously been contaminated with PCBs and portions had been remediated. This study aims to determine the effects this remediation had on transitional floodplain forests, as well as provide a preliminary biodiversity assessment for sites that are planned to be remediated of PCBs by the Environmental Protection Agency. The study was carried …

The Genetic Diversity Of An Endangered Buttercup, Ranunculus Triternatus, Ryan Garcia

All Master's Theses

Ranunculus triternatus, a rare endemic species of the Columbia River Gorge, faces conservation challenges due to its limited range and fragmented populations. This study assesses the genetic diversity of R. triternatus and compares it with its widespread congener, Ranunculus glaberrimus, using inter-primer binding site (iPBS) markers. Genetic data from 80 individuals across eight populations were analyzed using Nei’s genetic diversity, Shannon’s diversity index, and AMOVA. Results showed R. triternatus had higher genetic diversity than western populations of R. glaberrimus, with eastern populations of R. glaberrimus displaying greater diversity than western ones. PCA, UPGMA, and STRUCTURE analysis revealed …

Quantifying The Ecological Effects Of Salix Fragilis On Riparian Habitat In Kittitas County, Washington, Landon Shaffer

All Master's Theses

Invasive species threaten plant community structure and function globally. Riparian areas, the zone near streams where water influences vegetation, are especially sensitive to invasive species colonization, suffering large-scale shifts in community composition. Salix fragilis (crack willow) is a nonnative riparian species abundant in the lower elevation tributaries of central Washington. Some speculate whether this willow should be listed as invasive in Washington, despite a lack of regional supporting evidence. I studied riparian communities dominated by either S. fragilis or native species in the Kittitas Valley and measured biodiversity, quantified differences in solar attenuation, and compared leaf decomposition rates to learn …

Biology And Ecology Of Neonectria Magnoliae And Neonectria Punicea, Two Understudied Neonectria Species In West Virginia, Hannah Marie Petronek

Graduate Theses, Dissertations, and Problem Reports (ETD)

The family Nectriaceae includes numerous phytopathogenic fungi that cause canker diseases on both angiosperm and conifer hosts worldwide. Numerous Neonectria spp. cause cankers on hardwoods and conifers in North America, but their roles in contributing to tree decline and mortality outside of beech bark disease are largely understudied. One such pathogen, Neonectria magnoliae, causes perennial cankers on two native hosts in central Appalachia: Fraser magnolia (Magnolia fraseri) and tulip-poplar (Liriodendron tulipifera). We also recently confirmed N. magnoliae from non-native star magnolia (Magnolia stellata) in West Virginia. Both native hosts occur in the central …

Sweetening The Deal: Enhancing Flower Production And Quality For Native Pollinators In Urban Landscapes, Yaelle Esther Reeve

Honors Undergraduate Theses

Urban landscapes can support pollinator conservation, but traditional landscape designs lack the diverse mixtures of native plants needed to support native pollinators. Although native plants support pollinators and can survive with less water and fertilizer than non-native landscape plants, they do not always grow well under modified urban soil conditions and irrigation regimes. A better understanding of the factors influencing flower production and the quality of native plants is needed if we are to design landscapes that support pollinator conservation. This study focused on how flower production and quality in different native plants responded to compost and irrigation treatments. The …

Benthic And Epibenthic Invertebrate Assemblages Associated With Estuarine Submerged Aquatic Vegetation Differ Between Native And Invasive Plants, Marissa Hall, Kathryn O'Shaughnessy, Bethany Kiley, Ashley Mcdonald, Taber Faurie, Zoey Hendrickson, Anna Reimer, Samantha Smith, Charles Martin

Gulf and Caribbean Research

Estuarine submerged aquatic vegetation (SAV) provides vital habitat for macroinvertebrate communities that support diverse food webs and subsequent ecosystem services. Invasive SAV, however, has the potential to alter estuarine food webs through competition with native SAV, resulting in different associated biological communities. In the Mobile-Tensaw Delta (Alabama, USA), the invasive Eurasian milfoil, Myriophyllum spicatum, is fast becoming the dominant SAV, out-competing native SAV such as wild celery, Vallisneria americana. This study investigated the above- and belowground macroinvertebrate assemblages associated with these SAV habitats. We found significantly different assemblages between the SAV, with V. americana supporting more even and …

Documenting Plant Biodiversity At The Emu-Owned Parsons Center For Arts And Sciences, Emily Edwards

Master's Theses and Doctoral Dissertations

We present the first vascular plant species checklist for the Eastern Michigan-University-owned property called the Parsons Center for Arts and Sciences. A voucher for each plant species has been deposited in the Eastern Michigan College herbarium and collection data is digitized in the Consortium of Midwest Herbaria. A minimum of three images per species are also available on iNaturalist . The Consortium and iNaturalist databases are publicly available and provide georeferenced locations for each plant. One hundred seventy-one plant species (in 137 genera and 61 families) were documented and identified, representing about 15% of plant species and 41% of families …

Investigating Changing Macronutrient Dynamics At A Plant, Microbe And Plant-Microbe Interactions Scale, Emel Kangi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nutrient limitation drives forest ecosystem processes by altering net primary production, belowground (C) investments, and microbial activity. As such, the availability of essential macronutrients, such as nitrogen (N) and phosphorus (P), can severely impact plant growth, microbial decomposition, and the strength of plant-microbial interactions. However, our understanding of plant and microbe responses to changing nutrient availability, and the extent to which nutrient availability affects plant-microbe interactions, remains somewhat limited. Therefore, in this dissertation, I aimed to investigate nutrient limitation on a plant, microbe, and plant-microbe interaction level. First, to connect the phenotypic responses of nutrient-limited plants to key molecular mechanisms, …

Characterizing New Plant Fossils With Woody Growth From The Battery Point Formation Of Quebec (Canada), Emma T. Casselman

Cal Poly Humboldt theses and projects

The oldest woody growth has been recognized in several Early Devonian (ca. 410-395 Ma) euphyllophytes. Their taxonomic diversity is difficult to evaluate due to a lack of quantitative methods for comparing plants based on secondary xylem anatomy. In turn, this hinders understanding of their implications for the evolution of plant development. To develop metrics that quantify secondary xylem anatomy and allow for conclusive comparisons, I investigated extant taxa and Early Devonian fossil woody taxa. I developed multiple metrics for quantifying tracheid size as a function of position in the secondary xylem and tested them on a dataset of extant gymnosperms. …

Interactions Between New Zealand Mud Snails (Potamopyrgus Antipodarum) And Toxic Cyanoabacteria (Anabaena) In Baduwa’T (Mad River), Humboldt County, California, Cecilia F. Kennelly

Cal Poly Humboldt theses and projects

Invasive species in freshwater systems are circulated around the globe, wreaking havoc on natural communities. The New Zealand mud snail (Potamopyrgus antipodarum) is a very successful aquatic invader that has established populations in freshwater streams, lakes, and rivers around the globe. The goal of this project was to evaluate the interactions of invasive New Zealand mud snails (NZMS) and toxic cyanobacteria Anabaena in the Mad River in Humboldt County, California. These two species of concern are found in similar habitats along the river, but their whether NZMS consume Anabaena or affect toxin production is unknown. First, I conducted …

Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia

Journal of Nonprofit Innovation

Urban farming can enhance the lives of communities and help reduce food scarcity. This paper presents a conceptual prototype of an efficient urban farming community that can be scaled for a single apartment building or an entire community across all global geoeconomics regions, including densely populated cities and rural, developing towns and communities. When deployed in coordination with smart crop choices, local farm support, and efficient transportation then the result isn’t just sustainability, but also increasing fresh produce accessibility, optimizing nutritional value, eliminating the use of ‘forever chemicals’, reducing transportation costs, and fostering global environmental benefits.

Imagine Doris, who is …

Habitat And Demography Of The Ozark Chinquapin (Castanea Ozarkensis) At Roaring River State Park In Barry County, Missouri, Danielle Evilsizor

Electronic Theses & Dissertations

The Ozark chinquapin, Castanea ozarkensis Ashe, is a chestnut tree with a range concentrated in the Interior Highlands of North America. Like other North American members of Castanea, it was reduced from an overstory tree to an understory shrub by the invasive chestnut blight fungus (Cryphonectria parasitica [Murrill] M.E. Barr) during the early 20^th century. However, relatively little is known about the habitat of this species or its health and reproductive capability post chestnut blight. Chapter one of this study analyzed the habitat of this species through a random forest species distribution model (SDM) to predict where …

Addressing Water Hyacinth (Pontederia Crassipes) Impacts On Aquatic Biota In Lake Okeechobee, Joseph Salerno

All HCAS Student Capstones, Theses, and Dissertations

The incursion of water hyacinth, Pontederia crassipes in Lake Okeechobee has resulted in management systems to be implemented to reduce the coverage of the invasive macrophyte. Its residence in the Lake Okeechobee ecosystem and the effects it has on organisms in the lake, whether it be positive or harmful is unknown. This study attempted to assess the potential effects that water hyacinth has on aquatic biota in Lake Okeechobee. Biotic data were collected on open water, water hyacinth covered, and native vegetation covered habitats via hook-and-line fishing, electrofishing, baited minnow traps, and the sampling of plant roots over a thirteen-month …

Reducing Inputs And Adding Value To Turfgrass Systems Through Clover Inclusion And Plant Growth-Promoting Rhizobacteria Applications, Paige E. Boyle

All Graduate Theses and Dissertations, Fall 2023 to Present

Recently, the US has seen an expansion in the amount of turfgrass land cover (lawns, parks, roadsides, sports fields, and golf courses), as well as an interest in reducing fertilizer, water, and pesticide use in these grass systems. To help maintain quality and function while reducing resource inputs, two promising approaches have emerged: planting clover into lawns and applying plant growth-promoting rhizobacteria.

White clover and grass mixtures have been studied for their ability to cut down on fertilizer usage and provide a uniform, dark green lawn, but other clover types have not been as widely studied and may provide similar …