Digital Commons Network^™

Environmental Dna Identifies Coastal Plant Community Shift 1,000 Years Ago In Torrens Island, South Australia, Nicole R. Foster, Alice R. Jones, Oscar Serrano, Anna Lafratta, Paul S. Lavery, Kor-Jent Van Dijk, Ed Biffin, Bronwyn M. Gillanders, Jennifer Young, Pere Masque, Patricia S. Gadd, Geraldine E. Jacobsen, Atun Zawadzki, Andria Greene, Michelle Waycott

Research outputs 2022 to 2026

Anthropogenic activities are causing detrimental changes to coastal plants– namely seagrass, mangrove, and tidal marshes. Looking beyond recent times to past vegetation dynamics is critical to assess the response and resilience of an environment to change. Here, we develop a high-resolution multi-proxy approach, providing a new evidence base to decipher long-term change in coastal plant communities. Combining targeted environmental DNA analysis with chemical analysis of soils, we reconstructed 4,000 years of change at a temperate wetland on Torrens Island South Australia and identified an ecosystem shift that occurred ~ 1000 years ago. What was once a subtidal seagrass system shifted …

Study Of The Diversity Of Soil Animal Community In The Songnen Plain Grassland Of China, Yin Xiuqin, Zhu Tingcheng, Zhong Weiyan, Peng Wu Kui

IGC Proceedings (1997-2023)

This paper makes a diversity study of 8 habitats of soil animal communities in Songnen plain grassland. The research shows that the better the habitat condition is, the higher the diversity index of soil animals, and the worse the habitat condition is the lower the diversity index of soil animals. The diversity of soil animal communities has a positive relationship with soil organic matter, total nitrogen, and has a negative relationship with pH value. It has no obvious relationship with soil water content and total phosphorus. The diversity of soil animal communities decreases with increasing depth of soil layer and …

Clipping Intensity Impacts On Root Mass Variation Of Cool Season Grasses, D L. Stetson, W M. Sullivan

IGC Proceedings (1997-2023)

Seasonal changes in grass root and mat weight density were documented under different cutting managements. Kentucky bluegrass (Poa pratensis L.) and tall fescue (Festuca arundinacea Schreb.) received one annual cut, twice yearly forage harvest, and mown turf treatments. Orchardgrass (Dactylis glomerata L.) received one annual and twice yearly cutting treatments. Soil cores were collected to a 15 cm depth and divided into 7.5 cm increments. Roots and mat were recovered, washed, dried and weighed. Differences in years, seasons, species, treatments, and soil depth significantly influenced total root weight density and fine root density. With all species and …

The Core Of It All: From The Forest To The Concrete Jungle, Ayo Andra J. Deas

Dissertations, Theses, and Capstone Projects

The Core of It All is a component of principle within Fasaha. The mission of Fasaha is to implement programming directed toward development of one’s Core through self-actualization. Self-Actualization is defined as bringing forth the total essential qualities of one’s own consciousness, character, and identity through positive behavior. Throughout this manuscript, principle is defined as the standard of natural essential qualities determining intrinsic consciousness, character and identity. Programming is defined as providing with intrinsic instructions for the automatic performance of a task.

Fasaha is a support service that enhances the existing organization’s service. Throughout this dissertation, it will be apparent …

An Examination Of The Ways In Which Transdisciplinary Research Could Be Used To Incentivize Local Communities To Combat The Illegal Wildlife Trade, Jessica Rios

FIU Undergraduate Research Journal

The illegal wildlife trade (IWT) is currently one of the most critical conservation concerns, given its direct impact on biodiversity loss, endangering local ecosystems, and adding pressure to all species at a point when they face dangers like deforestation and mass extinctions. This industry also significantly impacts local communities, many of which are compelled to engage in it as a result of their precarious socioeconomic conditions. While effective countermeasures to this global issue have been identified, successful implementation of these countermeasures require diverse disciplines and collaborators. This paper argues that a transdisciplinary approach that converges knowledge and skills from social …

Evaluation Of Avian Use Of Agricultural Cover Crops During The Winter, Migration Stopover, And The Breeding Season In Tennessee, Brittany Panos

Masters Theses

The U.S. Department of Agriculture Natural Resources Conservation Service administers the cover crop program to provide technical and financial assistance to agricultural producers to sow herbaceous plant seeds to establish cover crops to protect agricultural fields from soil erosion during the non-growing season (late fall through spring). Soil retention and water quality benefits have been documented, but potential benefits for avian wildlife remain largely unknown. I used line-transect avian and vegetation surveys to examine use of cover crop fields by birds during the non-breeding period (winter), migration, and the breeding season. I compared avian use of cover crop fields with …

Consequences Of The Megafauna Extinction: Changes In Food Web Networks On The Edwards Plateau Across The Pleistocene-Holocene Transition, Quentin A. Smith Jr.

School of Biological Sciences: Dissertations, Theses, and Student Research

We are experiencing biodiversity loss due to climate change and human impacts, which is not only harmful to the environment but can also alter the composition of communities and interactions among species. The late Pleistocene experienced a loss of large-bodied mammals which resulted in significant changes in community structure due to changes in body size, diet, and species associations. The impact of these changes on species interactions and community structure across the Pleistocene-Holocene transition remains poorly understood. Using a robust data set of species composition, stable isotopes, body size, and climate variables, we constructed and compared ecological networks of mammal …

Mercury Biomagnification In Aquatic Food Webs Of Great Smoky Mountains National Park, Zachary Winston Clark

Masters Theses

Mercury is a widespread pollutant threatening human, fish, and ecosystem health on a global scale. Biomagnification concentrates mercury in upper trophic level organisms including predatory fishes, a primary route of dietary mercury exposure for humans. However, mercury biomagnification is not well understood in stream ecosystems, especially in places with no known point sources of contamination. A 2016 study revealed that Smallmouth Bass Micropterus dolomeiu mercury concentrations varied between three streams in Great Smoky Mountains National Park (GSMNP), Tennessee USA. However, the reason for this spatial variation in mercury concentrations is not understood. Our objectives were to (1) measure environmental and …

Effects Of Nitrogen On The Growth Of Hyparrhenia Diplandra, J Nkandza

IGC Proceedings (1997-2023)

The nitrogen effects on Hyparrhenia diplandra were studied. Plants were grown on nutrient solutions of variable concentrations in nitrogen. The supplied nitrogen increased tillering, leaf production, lamina area, total dry matter accumulation and total nitrogen accumulation in lamina. A detailed examination showed that the effect on tillering was the main cause of the differences observed in dry weights between different treatments. The nitrogen supply elongated significantly the lamina and nitrogen deficiency increased its thickness; but this was not enough to compensate the loss of weight in lower nitrogen treatment. The lamina area as well as nitrogen accumulation in the lamina …

Movement Of Allelopathic Compound Coumarin From Plant Residue Of Sweet Vernalgrass (Anthoxanthum Odoratum L.) To Soil, Yoshito Yamamoto

IGC Proceedings (1997-2023)

This study investigated the movement of coumarin, an allelopathic compound, from the plant residue of sweet vernalgrass (Anthoxanthum odoratum L.) to soil, as well as the dynamics of coumarin in soil. The level of coumarin dissolved from sweet vernalgrass plant residue in both Andosols and Cambisols, which were watered every day, peaked on the 5th day after the beginning of watering, and fell gradually with each additional of day. Specifically, the coumarin content in Cambisols on the 5th day was 14.2 ppm, which is 4 times the coumarin level found in Andosols. The recovery percentage of coumarin extracted with …

Stability Of Predator-Prey Model For Worm Attack In Wireless Sensor Networks, Rajeev Kishore, Padam Singh

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, we propose a predator-prey mathematical model for analyzing the dynamical behaviors of the system. This system is an epidemic model, and it is capable of ascertaining the worm's spreading at the initial stage and improving the security of wireless sensor networks. We investigate different fixed points and examine the stability of the projected model.

Comparison Of Ketamine-Xylazine, Butorphanol-Azaperone-Medetomidine, And Nalbuphine-Medetomidine-Azaperone For Raccoon (Procyon Lotor) Immobilization, Shylo R. Johnson, Christine K. Ellis, Chad Wickham, Molly R. Selleck, Amy T. Gilbert

USDA Wildlife Services: Staff Publications

Raccoons (Procyon lotor) are frequently handled using chemical immobilization in North America for management and research. In a controlled environment, we compared three drug combinations: ketamine-xylazine (KX), butorphanol-azaperone-medetomidine (BAM), and nalbuphinemedetomidine- azaperone (NalMed-A) for raccoon immobilization. In crossover comparisons, raccoons received a mean of the following: 8.66 mg/kg ketamine and 1.74 mg/kg xylazine (0.104 mL/kg KX); 0.464 mg/kg butorphanol, 0.155 mg/kg azaperone, and 0.185 mg/kg medetomidine (0.017 mL/kg BAM); and 0.800 mg/kg nalbuphine, 0.200 mg/kg azaperone, and 0.200 mg/kg medetomidine (0.020 mL/kg NalMed-A). Induction time was shortest with KX (mean6SE, 10.060.7 min) and longest with NalMed-A (13.061.3 min). …

Identifying Nutrient Dynamics And Relative Groundwater Contribution In Wetlands At Fish Lake Environmental Center, Lapeer Mi, Rose Allen

Senior Honors Theses and Projects

Wetlands are complex ecosystems that are dependent on hydrologic processes and water chemistry. Understanding the role that water chemistry and nutrients play in wetland ecosystems is crucial to wetland management and restoration. The Fish Lake Environmental Education Center near Lapeer Michigan, is glacially influenced, and contains a large bog. Between the bog and lake there are multiple kettles that contain ephemeral wetlands in the spring. Bogs are primarily precipitation sourced, whereas the kettle wetlands may be a combination of precipitation and groundwater sourced. Previous studies indicated that groundwater flow direction is towards Fish Lake, but it was unclear to what …

Dryland Vegetation Mapping Using High Spatial-Temporal Resolution Satellite Imagery In New Mexico: A Comparison Of Phenological Time-Series Transformation Methods, Pratistha Sharma

Geography ETDs

New Mexico's drylands are undergoing notable vegetation changes due to rising aridity, higher temperatures, and shifts in precipitation with changing climate. Mapping drylands through remote sensing is challenging compared to mesic systems due to the irregular patterns of rainfall-driven phenology and weaker vegetation absorption signals. This study aims to enhance vegetation mapping in New Mexico, utilizing a high-resolution, frequently revisited PlanetScope dataset with multispectral capabilities, specifically chosen for its suitability for time-series analysis. The challenge with high spatial and temporal data lies in the overwhelming volume, leading to issues like the curse of dimensionality, overfitting, data redundancy, collinearity, and visualization …

Tiny Drifters Amidst Global Change: Examining Environmental Drivers, Trophic Impacts, And Management Strategies Of Estuarine Plankton Communities In The Anthropocene, Taylor Nicole Dodrill

Dissertations and Theses

Plankton productivity supports estuarine food webs, and has been tied to the success of fisheries, macroinvertebrates, and cultured shellfish yields. Climate change and alterations to nutrient loads are thought to be influencing plankton assemblages, with toxin-producing harmful algal blooms (HABs) on the rise and nutritional quality of plankton declining globally. These shifts in plankton communities may contribute to low biomass yields and toxin-based closures of important fisheries. The objectives of this dissertation are to identify environmental drivers, trophic impacts, and management strategies to understand and respond to changing estuarine plankton communities. To address these objectives, I used a combination of …

Human Dimensions Of Woody Encroachment Management In Nebraska, Emily Rowen

School of Natural Resources: Dissertations, Theses, and Student Research

Woody plant encroachment (WPE) is a social-ecological problem that will challenge conservation professionals and agricultural producers to adapt their management strategies. This research first examined WPE from the perspective of individual conservation professionals through an online survey. Conservation professionals’ attitudes about adaptation to vegetation transitions, such as WPE, were of interest because these attitudes are one measure of how prepared this group is to respond to WPE. Hypothesized predictors of adaptation attitude were tested through linear regression modeling. These predictors included ecological change, observation of WPE, or risk perception. It was found that risk perception was the strongest predictor of …

In Situ Water Sensing Systems: Research On Advancements In Environmental Monitoring, Abigail Seibel

Honors Theses

In this work, two sensing systems were researched in order to improve in situ environmental monitoring. The first is a pH and Total Alkalinity sensor used to determine these characteristics of sea water. I explored the facets of this sensor over a 7-week internship with Dr. Ellen Briggs in her lab in summer of 2023. The second is a more holistic sensing system that reads temperature, turbidity, and pressure used for studying environmental characteristics of Alaskan bever ponds. Both systems were developed in close collaboration with scientists who are collecting data to better understand the impacts of climate change. Better …

Inundated Vegetation Response To Ongoing Restoration And Its Impacts On Fish Community Structure, Emmanuel J. May

All Graduate Theses and Dissertations, Fall 2023 to Present

Shallow lake ecosystems and their associated wetland habitats globally are subject to non-native species introductions, nutrient loading, and water level fluctuations, each of which can decrease vegetated habitat availability, exposing vulnerable native aquatic species to predation. Managers are frequently tasked with mitigating native species declines by restoring vegetation considered crucial for their survival. However, restoring vegetation can be challenging in the presence of multiple stressors, requiring managers to assess the relative importance of the different stressors limiting vegetation recovery.

Utah Lake is a large shallow lake subject to multiple stressors and has shifted from a mesotrophic lake with abundant aquatic …

Characterization Of The Long-Distance Dispersal Kernel Of White-Tailed Deer And Evaluating Its Impact On Chronic Wasting Disease Spread In Wisconsin, Mennatallah Gouda

All Graduate Theses and Dissertations, Fall 2023 to Present

Chronic Wasting Disease (CWD) is a fatal, untreatable neurodegenerative disease that infects deer and related species. It is highly contagious and caused by abnormal malfunction and assembly of normal cellular proteins into aggregation-prone proteins. The Centers for Disease Control and prevention report that the prevalence of CWD in free-ranging deer in the US is still relatively low. However, in several states the infection rates exceed 1 deer in 10. Deer may uptake CWD from direct interaction with infected individuals or from the environment. Infected individuals shed CWD into the environment through feces, urine, saliva or carcasses, and long-distance dispersal of …

Evaluating The Efficacy Of Chatgpt In Navigating The Spanish Medical Residency Entrance Examination (Mir): Promising Horizons For Ai In Clinical Medicine., Francisco Guillen-Grima, Sara Guillen-Aguinaga, Laura Guillen-Aguinaga, Rosa Alas-Brun, Luc Onambele, Wilfrido Ortega, Rocio Montejo, Enrique Aguinaga-Ontoso, Paul Barach, Ines Aguinaga-Ontoso

Department of Medicine Faculty Papers

UNLABELLED: The rapid progress in artificial intelligence, machine learning, and natural language processing has led to increasingly sophisticated large language models (LLMs) for use in healthcare. This study assesses the performance of two LLMs, the GPT-3.5 and GPT-4 models, in passing the MIR medical examination for access to medical specialist training in Spain. Our objectives included gauging the model's overall performance, analyzing discrepancies across different medical specialties, discerning between theoretical and practical questions, estimating error proportions, and assessing the hypothetical severity of errors committed by a physician.

MATERIAL AND METHODS: We studied the 2022 Spanish MIR examination results after excluding …

Evaluating Functional Diversity As Potential Early-Warning Indicator Of Rangeland Degradation, L.-M. Schwarz, C. P. Carmona, M. C. Bilton, F. Munyebvu-Chambara, K. Behn, A. Linstädter

IGC Proceedings (1997-2023)

Droughts and overgrazing play a crucial role in the degradation of semi-arid rangelands. This is evident in the loss of palatable long-lived grass species and bush encroachment. Early warning indicators are needed to mitigate long-term degradation and decline in essential forage provision. Functional diversity provides valuable information on ecosystem health. However, functional diversity indices have not yet been tested regarding their applicability as early warning indicators, revealing non-linear threshold behaviour. We therefore examined the following questions: (1) How do functional diversity indices respond to grazing pressure? (2) Does land tenure affect the relationship between functional diversity and grazing pressure? (3) …

Learning To See With Minimal Human Supervision, Zezhou Cheng

Doctoral Dissertations

Deep learning has significantly advanced computer vision in the past decade, paving the way for practical applications such as facial recognition and autonomous driving. However, current techniques depend heavily on human supervision, limiting their broader deployment. This dissertation tackles this problem by introducing algorithms and theories to minimize human supervision in three key areas: data, annotations, and neural network architectures, in the context of various visual understanding tasks such as object detection, image restoration, and 3D generation. First, we present self-supervised learning algorithms to handle in-the-wild images and videos that traditionally require time-consuming manual curation and labeling. We demonstrate that …

The Effects Of The Big-Headed Turtle (Platysternon Megacephalum) On Community And Ecosystem In Hong Kong Hill Streams, Wing Lam Fok

Lingnan Theses and Dissertations (MPhil & PhD)

Freshwater turtles and tortoises are ecologically important organisms; however, they are underappreciated, and conservation attention often focuses on the more charismatic animals such as birds and mammals. Although turtles are the most traded group of animals and many species are at the brink of extinction, little research has been done to understand their ecology in Asia because of the rarity of wild populations. Hong Kong is a biodiversity hotspot for freshwater turtle species. The Big-headed Turtle (Platysternon megacephalum) is a critically endangered species that still maintains small populations in Hong Kong, providing a rare opportunity to study the …

Modeling The Long-Distance Effects Of Predation, Henry Ogu

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

First Approximation Of Population Distributions On The International Space Station, Justin St. P. Walsh, Rao Hamza Ali, Alice C. Gorman, Amir Kanan Kashefi

Art Faculty Articles and Research

This paper presents an analysis of data derived from thousands of publicly available photographs showing life on the International Space Station (ISS) between 2000 and 2020. Our analysis uses crew and locational information from the photographs’ metadata to identify the distribution of different population groups—by gender, nationality, and space agency affiliation—across modules of the ISS, for the first time. Given the significance of the ISS as the most intensively inhabited space habitat to date, an international cooperative initiative involving 26 countries and five space agencies, and one of the most expensive building projects ever undertaken by humans, developing an understanding …

The Influence Of Spatiotemporal Variation In Food Web Models, Cecilia E. Heuvel

Electronic Theses and Dissertations

Aquatic ecosystems are constantly adapting to fluxes in season, temperature, nutrient cycling, and prey availability. Consequently, aquatic food webs are dynamic, and relationships between species are perpetually changing as organisms and primary producer communities adapt to current environmental conditions both in time and space. Despite this knowledge however, many food web studies continue to use temporally static and spatially homogenous representations of food webs. This thesis proposes that a detailed investigation of temporal and spatial trends in a large lake ecosystem can improve our understanding of the mechanisms and drivers of spatial and temporal variation in food web structure and …

Analyzing Human - Nonhuman Primate Conflict Mitigation Techniques In Mto Wa Mbu, Northern Tanzania, Lily Adams

Independent Study Project (ISP) Collection

Human – non-human primate conflict is particularly crucial due to primates’ high capacity to live among human populations. The study to analyze Human - Nonhuman Primate Conflict Mitigation Techniques, was carried in November 2023 at Mto wa Mbu, Northern Tanzania. To analyze techniques currently being used to mitigate human – non-human primate conflict, this study collected data through semi-structured interviews. Over 87% (n=35) of respondents used multiple mitigation techniques simultaneously. 80% of respondents (n=32) reported using projectiles to ward off foraging primates, 75% of respondents (n=30) reported using loud noises (made either by the voice/body or by manipulating noisemakers), 67.5% …

Influence Of Lake Volume On Trophic Position, Carbon Use, And Resource Partitioning In Fish Across A Narrow Range Of Ecosystem Size, Alyssa Andersen

Electronic Theses and Dissertations

Lake size is an important factor governing seasonal variation in limnological phenomena, origin of nutrient sources, species interactions, cross-habitat linkages, and trophic pathways, all having complex influences on food web structure and function. Lake size effects are most clearly demonstrated across very wide gradients in surface area or volume. This approach incorporates several complicating and collinear elements such as changing fish assemblages and species richness, and therefore, incorporates additional but unaccounted shifts in food web structure and function. A comparison across a finer lake size gradient where fish assemblages and species richness change little or not at all is needed …

Establishing A Monitoring Framework To Evaluate Impacts Of Grazing Exclusion And Inform Restoration At Santa Rita Ranch, Annie Booth, Annie Booth

Master of Science in Environmental Sciences and Management Projects

Santa Rita Ranch is a 1,750-acre cattle ranch in Templeton, California, that was privately owned and continuously grazed for the past 70 years. In 2021, The Land Conservancy of San Luis Obispo (LCSLO) acquired the property, and in the winter of 2022, they built a fence that bisects the ranch, excluding the cattle from 800 acres to preserve the riparian habitat. The LCSLO is currently defining the ecological baseline for the ranch to inform future management decisions. Given that cattle grazing has many environmental tradeoffs, they wanted to establish a long-term monitoring study to understand how relieving the pressures of …

Variation Of Ldmc And Sla Relationship Between Growth Forms In Natural Grasslands, J. Viégas, P. Cruz, J. P. Theau, C. Jouany, P. Ansquer, R. Al Haj Khaled, O. Therond, M. Duru

IGC Proceedings (1997-2023)

In agro-ecological studies, there is a growing interest in measuring both leaf dry matter content (LDMC) and specific leaf area (SLA). This interest lies on the fact that leaf traits are linked to gradients of environmental factors and ecosystem functions. Working with three contrasting wild species, Garnier et al. (2001) proposed a model linking these two traits. The model shows a relatively simple non linear and negative correlation between LDMC and SLA. Nevertheless, none of the species used to build the model were grasses (GRA) or forb rosettes (ROS = i.e. dicotyledonous with large entire leaves and absence of …