Terrestrial and Aquatic Ecology Commons^™

Patterns Of Fire History And Vegetation Changes In The Last 5000 Years: A Paleoecological Study Of Iquitos, Annabel Zwarts

Theses and Dissertations

The vegetation of the Amazonian rainforest is hypothesized to have been shaped by pre-Columbian activities, such as burning and palm management to various extents. Management of palms is hypothesized to have caused some of the most useful species to become hyperdominant in Amazonia. This study investigated the extent to which human activities over the past 5000 years affected palm abundances in mature lowland rainforests near Iquitos, Peru. I used phytoliths and charcoal from soil cores to determine the history of local floras, and modern palm surveys to compare modern phytolith occurrence with modern vegetation. Because pre-Columbian activity clustered along the …

Landscape Effects On The Beneficial Arthropod Community In Agriculturally Dominated Environments, Hannah E. Stowe

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Ecosystem services in agriculturally dominated regions rely, at least in part, on arthropods. Environment and biodiversity influence beneficial arthropods in population size, community structure, diversity, and ecosystem service provisioning. Predation is among the most important services provided by arthropods in agroecosystems. Understanding what alters predation and predator activity can support the successful application of biological control and, more broadly, integrated pest management. Land use and edge adjacency, field characteristics, landscape, seasonality, and diel period all alter predatory behavior. Crop fields dominate Nebraska agroecosystems, although interspersed perennial grasslands persist through the Conservation Reserve Program (CRP). Such grasslands supply crucial resources and …

Modifying The Comb, Rethinking The Install: Integrated Approaches To Honey Bee Colony Establishment And Winter Survival, Shelby A. Kittle

Department of Entomology: Dissertations, Theses, and Student Research

The European, or Western honey bee (Apis mellifera L.) plays a vital role in global ecosystems and agriculture, providing essential pollination services and producing valuable hive products. However, honey bee colony losses have escalated worldwide, but particularly across the United States due to various stressors, including biotic and abiotic factors, mismanagement, and environmental challenges. This thesis investigates key challenges in honey bee management and explores solutions aimed at improving colony health and productivity.

Chapter 1 provides an overview of the beekeeping industry, detailing its economic importance, services, and products, as well as the many challenges faced by beekeepers. It …

17 - Mapping The Spatial Distribution Of Submerged Aquatic Vegetation Using Commercial Satellite Imagery, Brandon Watson

Undergraduate Research Symposium

Seagrass in the Chesapeake Bay has seen an increase due to restoration efforts since the 90s, but with the extreme change of climate, we are unsure if the seagrass will thrive or perish, and where it will occur in the bay. Seagrass stabilizes coastal sediments, reducing erosion and protecting shorelines. It provides crucial habitats and nursery grounds for a diverse range of marine species, supporting both biodiversity and fisheries. Additionally, they play a significant role in carbon sequestration, which mitigates the effects of climate change. This study specifically looked at the area from the mouth of the Rappahannock River up …

Plant Biodiversity Of Short-Grass Prairie On An Eastern Colorado Cattle Ranch From 1988-2024, Emilee D. Cole, Zoey E. Daniels-Sneed, Matthew Galliart, Sarah Elzay

SACAD: Scholarly Activities

This survey examined the possible effects that rotational grazing and large-scale beef cattle production has on plant diversity in short-grass prairie rangeland. The survey was conducted on the Frasier Ranch, a working cattle ranch in eastern Colorado. Plant diversity was measured via species richness, ratio of cool to warm season grasses, and Shannon-Weiner Diversity Index. In this case study, it was determined that plant diversity did not change significantly in recorded years from 1988-2024.

Lawn Nutrient Availability And Run-Off During Establishment Under Enhanced Biodiversity, Masami S. Kanyuk

Environmental Studies Honors Theses

Biodiversity has consistently been found to have positive ecosystem effects, including erosion mitigation and stability of nutrient cycling. For lawns, this can translate to reducing the need for fertilizer application, and reducing soil loss and leaching that can impact water quality. This paper investigates the effects of biodiversity and plant community establishment in a lawn ecosystem on soil erosion, nitrate leaching via porewater sampling, and plant available nitrogen.

In the first growing season of PLEDGE (the Pastures and Lawns Enhanced Drought and Global-Change Experiment), we hypothesized that three-species lawns (tall fescue, dwarf white clover, and creeping thyme) would experience higher …

Ms Environmental Biology Capstone: Evaluating Environmental Risks And Conflicts In Golf Course Landscapes, Meredith Boos

Regis University Student Publications (comprehensive collection)

1) This review investigates the relationship between pesticide use on golf courses and in agriculture to determine whether the adverse health effects documented in agricultural settings also apply to golf course environments. While the negative health effects from agricultural pesticide use are well established, golf courses use pesticides with greater frequency and intensity, suggesting a potentially higher exposure risk for both workers and players.

2) This study proposes methods to quantify pesticide bioaccumulation on golf courses and adjacent lands. We hypothesize that areas surrounding golf courses will exhibit a spatial gradient of pesticide accumulation, increasing with proximity to treated sites …

Restored Wetlands Show Rapid Vegetation Recovery And Substantial Surface-Water Expansion, Thilina D. Surasinghe, Yin-Hsuen Chen, Kunwar K. Singh

Center for Geospatial Science, Education & Analytics Faculty Publications

Ecological restoration is essential for improving the ecological integrity of degraded ecosystems to enhance ecosystem services and biodiversity. In this study, we assessed the effectiveness of wetland restoration on retired cranberry farms by analyzing vegetation recovery and surface-water dynamics using the enhanced vegetation index (EVI) and normalized difference water index (NDWI) derived from Sentinel-2 satellite imagery. To quantify temporal dynamics of both vegetation recovery and surface-water cover, we identified the spectral distinctions among restored wetland plant communities. Our results indicated the emergence of distinct plant communities upon restoration. Restored wetlands in general showed significant and progressive vegetation recovery and expanding …

Modeling Wild Rice Bed Health: A Dual Metric Approach For Bed Strength And Invasive Impact, Seth Sisneros-Martinez

Journal of Earth and Life Science

Wild rice (mannoomin; Zizania palustris) is an aquatic grain that grows in slow-moving rivers and shallow bays throughout northern Minnesota. In Headquarters Bay on Leech Lake, wild rice has served as a cultural staple for Indigenous communities for centuries. However, its population has declined in recent years due to multiple environmental issues. One potential contributor is Eurasian watermilfoil (Myriophyllum spicatum; EWM), an invasive species that forms dense mats capable of outcompeting native aquatic vegetation, including wild rice. EWM was first recorded on the southern shoreline of Leech Lake in 2005 and has since become widespread. This study …

Bioremediation In The Chesapeake Bay: Anthropogenic Ocean Acidification Mitigation In An Interactive Multi-Trophic Ecosystem, Cree Taylor

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

Zostera marina is a species of marine macrophyte that has been largely prioritized in past submerged aquatic vegetation (SAV) restoration initiatives within the Chesapeake Bay because of its 1) previous abundance, 2) demonstrated carbon burial abilities, and 3) observed ability for meadows of Z. marina to ameliorate low pH conditions. Due to the temperature variability and poor water quality in the Chesapeake Bay, Z. Marina beds have experienced several die-off events with limited capacity for regrowth. Ruppia maritima, an opportunistic species with tolerance to temperature shifts within the bay, may have the potential to maintain SAV coverage in areas …

Rejuvra's Effect On Soil Seed Banks, Blake J. Roeslein, Bryan Endress, Abby Mcmurtry, Akasha Faist

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Invasive annual grasses are a major driver of grassland degradation globally. In perennial grasslands, invasion can heavily impact biodiversity, including potential changes to the soil seed banks. Seed banks, the living seeds stored in the upper soil column, play an important role in healthy systems, or can harbor invasive species. To reduce negative invasion outcomes, whether in the seed bank, or aboveground vegetation, pre-emergent herbicides are a commonly used tool for land managers. Pre-emergent herbicides work by targeting seeds as they germinate and begin emerging from the soil. Thus, our study asks 1) how does pre-emergent herbicide influence germination and …

The Spatial And Temporal Dimensions Of Plant–Soil Feedback In Native Perennial Monocultures, Bret Lang

Electronic Theses and Dissertations

Plant-soil feedbacks (PSFs) describe how plants change their soil environment in ways that can either negatively or positively affect subsequent plant growth. In doing so, they offer an opportunity to connect ecological processes with agricultural practice. My dissertation examines PSFs created by native perennial monocultures, commonly used for native seed production, across time and space, and through soil legacies. Specifically, I focus on how plant species identity shapes both soil nutrient and soil microbial community responses. To address these questions, I conducted field experiments with monocultures of five forb species native to South Dakota and established plots with these species …

Investigating The Mechanisms Of Freeze Tolerance In Lemna Minor, Tamara Bouchard

Honors Theses and Capstones

Freezing presents a significant abiotic stress to aquatic plants, yet little is known about the mechanisms by which species like Lemna minor (duckweed) survive subzero temperatures in nature. This study investigates whether L. minor employs freeze-avoidance or freeze-tolerance strategies and explores the potential role of its microbiome in enhancing cold resilience. Using both field-collected fronds from naturally frozen ponds and controlled freezing experiments in the lab, I assessed survival through viability staining and post-thaw survival. Results showed that L. minor can survive natural ice encasement and that prior cold acclimation significantly improves tissue survival under induced freezing. Trypan blue staining …

Effects Of Round-Up On The Environment, Sandra J. Marcu

Journal of Earth and Life Science

Many people around the world have used and still currently use Roundup but are unaware of the effects it has on the environment. Roundup is a spray on application weedkiller that is widely used around the world today both residentially and commercially. It enables its user to grow a garden or a field of crops with a no-tilling approach to eliminate weeds. It is a well-known and popular choice for killing weeds that has been around since the mid 1970’s (Oca, 2017). John Franz, a Monsanto scientist discovered that glyphosate (main ingredient in Roundup) was an herbicide or weedkiller, and …

“Nice To See You”: Addressing Plant Awareness Disparity With Locally Specific Ecological And Cultural Plant Education, Cecilia Muecke

Pomona Senior Theses

Plants form the basis of life on Earth. However, due to the phenomenon of plant awareness disparity, a self-perpetuating cycle whereby plants are overlooked on an individual and global level ensues. Lack of plant awareness leads to a lessened emphasis on plants in sustainability and conservation as well as biology education, resulting in negative impacts on biodiversity and food security. The severity of plant awareness disparity is dependent on cultural context, and Indigenous and/or traditional societies are less likely to experience plant awareness disparity because of they are typically more connected to plants for their everyday needs. Native plants are …

Assessing Genetic Diversity And Population Structure In The Imperiled Aconitum Reclinatum (White Monkshood), An Endemic Wildflower Of Central Appalachia, Diamanda A. Zizis

Master’s Theses

Aconitum reclinatum, white monkshood (Ranunculaceae), is a Pennsylvania critically imperiled plant species found in five states of the Appalachian region of the United States: Pennsylvania, West Virginia, Virginia, North Carolina, and Tennessee. This plant is adapted to cool, moist environments but faces threats from increasing habitat loss, deer browse, logging, and changes in rainfall and temperature associated with climate change. Comprehensive knowledge of A. reclinatum genetic population structure remains limited. To address this, we collaborated with Natural Heritage programs within the range of A. reclinatum to sample populations across the species distribution and generate a genotyping-by-sequencing data set of …

Responses Of Native And Invasive Aquatic Vegetation To Changes In Water Depth In An Ozark Spring-Fed Pond, Daphne Miles

Graduate Theses/Dissertations

Spring-fed aquatic ecosystems in the Ozark Highlands are characterized by stable water depths, clear water, and diverse aquatic vegetation (filamentous algae, submerged, floating, and emergent plants). Sudden changes in water depth can impact aquatic vegetation dynamics but the impacts of prolonged changes are poorly understood. I investigated seasonal and annual changes to aquatic vegetation abundance in a spring impoundment during and after a two-year period of low water depth that was caused by a broken outlet below an artificial dam. Water depth was significantly lower in 2020 and 2021 (low water years), compared to 2022 and 2023 (high water years). …

Ocean Acidification Mitigation: Potential Expansion Of Sav Restoration Strategy In The Chesapeake Bay, Cree N. Taylor

Undergraduate Research Posters

Zostera marina is a species of marine macrophyte that has been largely prioritized in past submerged aquatic vegetation (SAV) restoration initiatives within the Chesapeake Bay because of its 1) previous abundance, 2) demonstrated carbon burial abilities, and 3) observed ability for meadows of Z. marina to ameliorate low pH conditions. Due to the temperature variability and poor water quality associated with anthropogenic disturbances in the Chesapeake Bay, Z. Marina beds have experienced several die-off events with limited capacity for regrowth. This systematic review explored the possible benefits of focusing future SAV recovery initiatives on ensuring a diverse variety of SAV …

Phytoplankton Responses To Changing Irradiance And Carbon Fertilization, Alison Siersma

Graduate Theses and Dissertations (2019 - present)

Phytoplankton play a crucial role in marine ecosystems due to their innate ability to fix carbon. As atmospheric CO2 levels continue to rise from fossil fuel combustion, the resulting increase in dissolved CO2 and the concurrent decrease in ocean pH are likely to impact the phytoplankton community. The response of phytoplankton to elevated CO2 can vary significantly among species and environmental conditions (e.g. light, temperature, nutrient availability). To address these variations, an experiment was conducted using a controlled photobioreactor system, maintaining high and low light, constant temperature, nutrient levels, and two pCO2 concentrations. This study focused on two regionally relevant …

Fire And Ant Interactions Mediated By Honeydew And Extrafloral Nectar In An Australian Tropical Savanna, Fernanda M. P. Oliveira, Carlos H. F Silva, Melinda L. Moir, Inara R. Leal, Alan N. Andersen

Natural Resources Research Articles

Fire is a major disturbance affecting ecosystems globally, but its impact on mutualisms has received minimal attention. Here, we use a long-term field experiment to investigate the impact of different fire regimes on globally important ant–honeydew and ant–extrafloral nectar (EFN) mutualistic interactions in an Australian tropical savanna. These interactions provide ants with a key energy source, while their plant and hemipteran hosts receive protection services. We examined ant interactions on species of Eucalyptus (lacking EFNs) and Acacia (with EFNs) in three replicate plots each of burning every 2 and 3 years early in the dry season, burning late in the …

2024 Fall Newsletter, Plaster Creek Stewards

Newsletters

Highlights:

Project GreenER Returns in 2025

Sustainable Business of the Year

PCS Is Showing Up Around the Community

Botanical Highlight: Discovery of a New Kent County Native Grass

Fall Event Furthers New Tree Planting Initiatives

Plaster Creek: Unsalted?

Making Connections at Calvin

Field-Based Courses Still Matter, But Not Like They Used To, Christopher T. Martine

Faculty Journal Articles

Increasingly, field-based courses are providing the first real opportunities for students to experience nature in meaningful ways. As a baseline, even before the content delivery and the graded assessments, this is already enough to change the way a person feels in the world and to spark an appreciation for the life around them.

(Part of a special feature on education in which recent winners of the Botanical Society of America's Charles E. Bessey Award share teaching philosophies and strategies.)

I’M A Forest, Not A Saltmarsh, Captain: Carbon And Sap Flow Dynamics In Coastal Forested Wetlands Of The Southeastern United States, Chris Shipway

All Theses

Coastal forested wetlands are identified as some of the highest-priority ecosystems for climate change mitigation. Here, we present two studies conducted in these unique ecosystems.

The first assessed changes in aboveground vegetative C stocks along the estuarine-riverine gradients of the Winyah Bay in South Carolina and the Savannah River in Georgia, using a space-for-time substitution to increase understanding of the impacts to upper estuarine forested wetlands from relative sea level rise. Standing C stocks on the Savannah River averaged 183.6 Mg C ha^-1, while sites on the Winyah system averaged 162.3 Mg C ha^-1. The largest …

Seed Dispersal By Martu Peoples Promotes The Distribution Of Native Plants In Arid Australia, Rebecca Bliege Bird, Douglas Bird, Christopher T. Martine, Chloe Mcguire, Leanne Greenwood, Desmond Taylor, Tanisha M. Williams, Peter M. Veth

Faculty Journal Articles

Commensal relationships between wild plants and their dispersers play a key ecological and evolutionary role in community structure and function. While non-human dispersers are often considered critical to plant recruitment, human dispersers have received much less attention, especially when it comes to non-domesticated plants. Australia, as a continent historically characterized by economies reliant on non-domesticated plants, is thus a key system for exploring the ecological role of people as seed dispersers in the absence of agriculture. Here, we utilize a controlled observation research design, employing ecological surveys and ethnographic observations to examine how seed dispersal and landscape burning by Martu …

Impact Of Containment And Elevation On Created Marsh Plant Community And Ecosystem Dynamics, Kevin R. Stoner

LSU Master's Theses

Coastal marsh restoration is increasing globally, as marshes are impacted by anthropogenic impacts. Billions of dollars are allocated to marsh restoration in the Mississippi River delta where wetland loss rates are extremely high. The recovery of structural and functional attributes of created marshes varies by attribute measured and project. Here, two marshes created in 2018 and one natural marsh were used to examine how variations in hydrologic connectivity and marsh elevation influence subsurface hydrology and salinity, vegetation community structure, soil properties, accretion, and denitrification. I established a comparative field study in a created marsh contained within a higher elevation containment …

Scientific Note: An Incursion Of The Widely-Cultivated Katsura (Cercidiphyllum Japonicum, Cercidiphyllaceae) In Pennsylvania, Kayleigh R. Long, Melody P. Sain, Elizabeth H. Williams, Christopher T. Martine

Faculty Journal Articles

Cercidiphyllum japonicum (katsura) is a dioecious tree native to China and Japan. Although imperiled in parts of its natural distribution, the species has become quite common as a cultivated tree in temperate North America. The species is noted as occasionally escaping cultivation in the eastern United States, but few records of established incursions (and the conditions under which they might recruit) exist in the literature. We here report an incursion of C. japonicum in central Pennsylvania, along with notes on seedling recruitment on the Bucknell University campus.

New Insights On Hybridization In Potamogeton Floridanus (The Florida Pondweed), Kaitlyn R. Sampson

Graduate Theses and Dissertations (2019 - present)

Freshwater ecosystems are some of the most important and highest threatened habitats in the world, and aquatic plants play an important, but often-overlooked, role in maintaining them. Potamogeton is a diverse and ecologically important aquatic plant genus well known for taxonomic difficulty and rampant hybridization. lbis study aimed to 1) test the hypothesis that Potamogeton jloridanus (Florida pondweed) is a hybrid between P. oakesianus and P. pulcher, and 2) to investigate correlations in ecological conditions for the focal species. This study revealed the discovery of a new population of P. jloridanus in Big Coldwater Creek in Santa Rosa Co., FL, …

Behavioural Distributions Of Macrophytes In An Oxbow Lake, Dhir Beel With Reference To Its Water Quality In Assam, India, Arup Nama Das, D. K. Sharma

Journal of Bioresource Management

An Oxbow lake, Dhir Beel, situated in Western Assam, India, stands as a habitat for a plethora of plant and animal species, nurturing a vibrant ecosystem within its freshwater environs. This study sought to address concerns surrounding pollution, encroachment, siltation, and overfishing within Dhir Beel. Over a span of three years (2016-2019), samples were meticulously collected from five distinct sites to analyze both water quality and macrophyte populations. Employing the APHA method, the physico-chemical parameters of the water were evaluated, while a comprehensive identification process was undertaken to categorize the macrophytes. These aquatic plants, spanning dicots, monocots, and pteridophytes, were …

A Library Of 39 Plant Peroxidases: Plants From The Families Cucurbitaceae And Brassicaceae Show Promising Peroxidase And Peroxygenase Activity, Sally Hess

Senior Honors Theses

Peroxidases are enzymes that reduce reactive oxygen species (ROS) and oxidize organic substances in living cells. The textile industry, wastewater treatment plants, immunological laboratories, and diagnostic laboratories have extensively used horseradish peroxidase for their oxidating needs. This research aims to provide a tool for identifying potentially useful sources of peroxidases in addition to specifically pinpointing a novel peroxygenase in jalapeño seeds. By using two widely accepted peroxidase assays, the guaiacol assay and the fluorophenol assay, fruits of the genus Cucurbita and roots or leaves of the family Brassicaceae were seen to have high peroxidase activity. Additionally, novel peroxygenase activity was …

From Pixels To Plants: Remote Sensing Of California Invasive Plants, Kenneth Rangel

Master's Projects and Capstones

Invasive plants cause significant impacts to ecosystems, the economy, and human health. California has experienced significant plant invasions and is well suited to future invasion because of its Mediterranean climate and human disturbance. Eradication or control of invasive plant species requires a detailed understanding of their spatial distribution, which typically involves on the ground surveys that can be expensive or inconsistent. Remote sensing offers a potential alternative or supplement to in-person invasive plant mapping. This study performed a comparative analysis of 41 remote sensing studies that mapped the distribution of California invasive plants. I found that while high spectral resolution …