Digital Commons Network^™

Construction Impacts On Nutrient Loads In An Urban Stream In The Ozark Highlands, Matthew B. Wilson

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Degradation of water quality is primarily caused by human activity, including urbanization. Urban stream syndrome can be characterized as a stream that has undergone physical, chemical, and biological changes as a result of urbanization, which can include an influx of nutrients that can drive unwanted plant and algae growth. It is known that construction can result in untreated nutrients entering a stream; however, it is not understood how construction affects downstream nutrient transport. The objective of this study was to understand the impacts of construction on urban water quality in Tanglewood Branch in Fayetteville, Arkansas, in the Ozark Highlands, which …

Post-Wildfire Erosion And Biogeochemistry: Integrating Aerial Imagery And Soil Testing To Assess Landscape Recovery, Justin A. Allred

All Graduate Theses and Dissertations, Fall 2023 to Present

After a wildfire, land managers are required to monitor large tracts of land with limited time and budgets. Traditionally, tracking landscape recovery is a time intensive process. This research explored the effectiveness of using drones (UAVs), strategic soil sampling, and computer modeling as additional tools for land managers in order to monitor the recovery more efficiently.

By using drones to collect aerial imagery and using machine learning, plant regrowth was monitored in back-to-back years. The machine learning model performed well at telling broad groups apart (trees vs grass) but it struggled to identify differences between plant species. Because many plants …

Assessing Geomorphic Change From Large Wood Additions In An Intensively Monitored Watershed, Alexander Walt

All Graduate Theses and Dissertations, Fall 2023 to Present

Rivers across the American West are under stress. Over time, human activities have decreased riparian vegetation and removed naturally occurring large wood from fallen trees and beaver dams. Overgrazing, wetland drainage, and artificial barriers like levees and berms have further changed these ecosystems, leaving behind simple channels that lack varied habitat for aquatic species.

Efforts to restore rivers have made some progress, but many projects are small in scale and focus more on reshaping the river rather than restoring the natural processes that keep it healthy. This study evaluates a different approach—Low-Tech Process-Based Restoration (LTPBR)—which works with nature to rebuild …

Soil Microbial Responses To Artifical Light At Night, Randall L. Walker

Open Access Theses & Dissertations

Global change, driven by both natural processes and human activities, has significantly transformed ecosystems. Urbanization and artificial light at night (ALAN) are key contributors, disrupting natural light cycles and influencing biological rhythms, biodiversity, and ecosystem functions. Thus far, there remains a gap in knowledge of how soil ecosystems are impacted by ALAN. This study uses a laboratory incubation to investigate the effects of ALAN on soil microbial communities and functions across urban and natural ecosystems. Briefly, soil was collected from eight sites around El Paso, Texas and neighboring New Mexico representing urban and rural light exposure. Soil was then subjected …

Exploring Connectivity And Element Distribution In The Critical Zone Using Deep Cores Below Agricultural And Natural Drylands In The American Southwest, Angie Lynette Cano

Open Access Theses & Dissertations

Water movement controls how solutes are transported and stored in arid Critical Zone (CZ) systems. In natural drylands, low precipitation and high evapotranspiration lead to long term salt accumulation in the CZ, whereas irrigation increases water input and increases downward solute transport. This study investigates how agricultural practices alter subsurface hydrology and geochemistry by comparing two deep CZ cores from the southwestern United States: a 50 m deep core beneath a flood irrigated pecan farm named 5R farm, in the Rio Grande Valley in Tornillo, Texas, and a 97.5 m deep core from the Red Lake Playa in the Jornada …

2024 Annual Operations And Maintenance Report 2024 Bres Annual Summary Report For Work Completed In Quadrant 4, Butte-Silver Bow Department Of Reclamation And Environmental Services

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Draft Final 2026 Interim Site-Wide Groundwater Monitoring Quality Assurance Project Plan, Woodard & Curran

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Final Revised Silver Bow Creek Conservation Area (Sbcca) Construction Quality Assurance Plan (Cqap), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

High Throughput Phenomics Pipeline For Pulse Crop Nutritional Breeding, Amod Udayanga Madurapperumage

All Dissertations

Dry pea (Pisum sativum L.), lentil (Lens culinaris Medik.), and chickpea (Cicer arietinum L.) are major pulse crops valued for their high nutritional composition and importance to global food systems. Pulses are rich in carbohydrates, protein, and essential minerals, making them ideal whole foods and critical contributors to food and nutrition security. Due to these advantages, pulse breeding programs are increasingly focusing on enhancing nutritional traits, such as protein quality, amino acid balance, and micronutrient density, through the process of biofortification. However, improvement of agronomic traits remains equally essential. Characteristics such as plant height, standability, stress tolerance, …

Geography, Income, And The Incidence Of A Massachusetts Carbon Tax, Susan Stratton Sayre

Economics: Faculty Publications

I use spatial microsimulation to estimate the geographic incidence of the consumer-facing portion of various revenue-neutral carbon tax designs in Massachusetts. I identify a substantial urban-rural disparity in impacts that is reduced, but not eliminated, by proposed revenue-targeting mechanisms. I further demonstrate that seemingly small variations in the definition of rural households can have substantial impacts on urban-rural equity and the distribution of gains and losses. Proposed policies are highly progressive in the aggregate with most low-income households receiving more in rebates than they pay in taxes, but notable numbers of low-income households are likely to experience significant losses. Methodologically, …

Low Methane Emissions From Nutrient-Rich Former River Channels In A Hydrologically Managed Dryland Delta, Siena Stassi, Jude A. Benavides, Chu-Lin Cheng, Marcelo Gomes Da Silva, Nicholas E. Ray, Nathan O. Barros, Rafael M. Almeida

School of Earth, Environmental, & Marine Sciences Faculty Publications

Anthropogenic stresses in dryland regions can alter hydrology, salinization, and biogeochemical processes. How these pressures influence methane (CH4) cycling and emissions from aquatic ecosystems remains poorly understood. Over the course of 1 year, we measured diffusive and ebullitive CH4 emissions from resacas—shallow, hydrologically managed distributary channels prevalent throughout the Lower Rio Grande Valley along the US–Mexico border. Despite warm, nutrient-rich waters, CH4 emissions from resacas were low, and more comparable to rates observed in estuarine systems. CH4 fluxes were positively related to temperature but negatively related to salinity and rainfall. Elevated salinity, driven by evaporation and source water from the …

Microplastic Composition And Exposure Pathways In Freshwater Systems: A Multi-Matrix Comparison Between Streams And Retention Ponds In Hamilton County, In, Mya Whaley

All-Inclusive List of Electronic Theses and Dissertations

Since the early 1900s, the use of plastics has increased exponentially. The breakdown of plastic materials has exposed all ecosystems to microplastics (small particles of plastic < 5 mm), which are now ubiquitous in natural settings. Microplastics have a relatively large surface area, and many chemicals adsorb to these small particles, impacting their fate and transport of pollution. While microplastics have been found in virtually every setting on Earth, research is necessary to understand their impact on freshwater ecosystems and biogeochemical cycles. The focus of this research was to investigate microplastic compositions in crayfish, sediments, and water samples collected in streams and retention ponds. We analyzed trends in microplastic counts across different land-cover classes, waterbody types, and species, and compared concentrations among matrices to improve our understanding of microplastic exposure pathways in freshwater ecosystems. As a secondary objective, lead and arsenic concentrations were analyzed from sediment samples to investigate metal burdens and compare them to microplastic concentrations. Our findings revealed that, in general, urban streams had the highest microplastic concentrations within land cover categories, and retention ponds had higher microplastic counts than streams. Crayfish, such as F. rusticus had higher microplastic concentrations than F. virilis and F. propinquus, although these results may be influenced by study design. The most common microplastic type was fibers, and most common color was transparent. There was no significant correlation between microplastic and metal concentrations in sediments. We found crayfish to be adequate bioindicators of microplastic pollution, because they were less impacted by environmental variability than sediment and water samples. This research presents the first evidence of microplastics in our study species, F. propinquus, F. rusticus, and F. virlis. This work presents new evidence of microplastic accumulation in crayfish, sediments, and water from freshwater systems in the Midwestern United States. Microplastics were found in every sample type—crayfish, water, and sediment—across urban, rural, and forested landscapes, highlighting their pervasive distribution. The findings provide foundational data for assessing emerging ecological and human-health risks and emphasize the importance of sustained monitoring and research on MP contamination in freshwater environments.

Low Climate Benefit Of Nordic Coastal Marshes: Site Conditions Outweigh Grazing Effects And Shape Trade-Offs Between Carbon Storage And Its Stability, Carmen Leiva-Dueñas, T. Banta, Christoffer Boström, Franziska Eller, Johan Eklöf, Line Holm Andersen, Kai Jensen, Marianna Lanari, Ella Logemann, Pere Masque, Thomas Ostertag, Christoph Reisdorff, Anaïs Richard, Anu Vehmaa, Jukka Alm, Mikael Von Numers, Dorte Krause-Jensen

Research outputs 2022 to 2026

Coastal marshes, recognized as effective organic carbon (OC) sinks, have gained attention for their potential contribution to climate mitigation through protection and restoration. However, the climate mitigation potential of Nordic coastal marshes remains understudied, likely due to their heterogeneous and often non-tidal nature. To fill this gap, we examined soil OC storage and accumulation rates, and the effects of grazing, a common management practice, across eight Nordic coastal marsh areas spanning broad climate and environmental gradients. We also assessed soil methane emissions in selected areas. The Nordic marshes studied store a median of 7 kg OC m⁻² (interquartile range, …

Ai-Driven Multispectral Drone Monitoring For Afforestation In Arid Environments, Hesham Morgan, Ali Elgendy, Brandon Tran, Tamer Ismail, Mohamed M. Moursy, Yehya Kh. Shehadeh, Ahmed Elgharib, Ahmed Abdullah Al-Dughairi, Ali El Mubarak, Khaled Allam Harhash, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Monitoring large-scale afforestation projects in arid and semi-arid environments requires accurate, high-resolution, and repeatable methods to assess tree survival and growth. In this study, we integrated unmanned aerial vehicle (UAV) multispectral imaging with an advanced object detection framework to evaluate vegetation establishment in the Shuayb Al-Budai afforestation site, part of the Imam Turki bin Abdullah Royal Natural Reserve, Kingdom of Saudi Arabia (KSA). Multispectral datasets were acquired using a MicaSense Altum-PT sensor and processed through a masked Region-based Convolutional Neural Network (RCNN) with two backbone architectures: ResNet-101 and VGG19-BN. The Mask R-CNN–ResNet-101 model achieved superior performance, with an overall accuracy …

Warming Climate Amplifies Vapor Pressure Deficit Limits On Gross Primary Productivity, Shiqin Xu, Nate G. Mcdowell, Tim R. Mcvicar, Diego G. Miralles, Stephen Sitch, Pablo Sanchez-Martinez, Joshua B. Fisher, Pierre Friedlingstein, Hylke E. Beck, Matthew F. Mccabe

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Ongoing climate warming may profoundly impact terrestrial gross primary productivity (GPP), a key component of the global carbon cycle. However, uncertainty in the relative roles of atmospheric water demand (vapor pressure deficit, VPD) and root-zone soil moisture (SM) limits predictions of drought impacts on GPP. Here, we show that growing-season GPP was more strongly constrained by VPD than SM globally, based on observation-constrained model estimates, satellite retrievals and Dynamic Global Vegetation Model simulations. The importance of VPD increased with higher temperatures and more severe and prolonged droughts. This pattern reflects VPD’s critical role in regulating stomatal conductance and plant hydraulic …

Re: Comment Letter For Draft Final 2026 Interim Site-Wide Groundwater Monitoring Quality Assurance Project Plan (Dated April 17, 2026), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Final Insufficiently Reclaimed Sites Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Final Unreclaimed Sites Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Evaluation Of Sirna-Mediated Knockdown Of Heat Shock Protein 16.2 In Adult Acropora Cervicornis, Edward P. Gniffke, Benjamin D. Young, Keir J. Macartney, Michael S. Studivan, Ian C. Enochs, Erin E. Easton

School of Earth, Environmental, & Marine Sciences Faculty Publications

Acropora cervicornis is a critically endangered Caribbean coral species facing a precipitous decline due to disease and thermal bleaching. To combat the loss of ecologically important reef-building corals, novel molecular approaches can be used to understand mechanisms of resilience and ultimately provide a means to modulate coral performance. In this study, we tested a recently developed method for gene knockdown in adult corals that utilizes short interfering RNAs (siRNAs) and the RNA interference pathway. The Heat Shock Protein 16.2 (HSP16.2) gene in fragments of adult A. cervicornis was targeted for knockdown using a single siRNA construct. RT-qPCR analysis of HSP16.2 …

Dynamic Prediction On Goaf Surface Subsidence For The Last Two Periods Based On The Erf Time Function, Ren Lianwei, Li Shihui, Wang Wenchang, Li Zhenhua, Chen Shaojie, Dun Zhilin

Coal Geology & Exploration

Background The surface subsidence induced by coal seam mining represents a continuous dynamic evolution process. Constructing a full-time perdition model for surface subsidence in goafs holds significant theoretical and practical values for the rational utilization of land resources, the safety guarantee of engineering construction, and the transformation and development of resource-based cities. Methods To accurately predict the surface subsidence in goafs during its decline and residual periods, this study proposed a prediction model based on the error function (Erf). First, the evolution characteristics of Erf were analyzed, verifying that the subsidence, as well as its velocity and acceleration, predicted using …

Optical Mechanisms Behind Vitrinite Reflectance Suppression Caused By Strong Anisotropy: A Case Study Of Contact Metamorphic Coals, An Yanfei, He Shuyang, Chen Kaixin, Gao Junhan

Coal Geology & Exploration

Objective For vitrinite with weak anisotropy, which proves uniaxial and optically negative, replacing random vitrinite reflectance (R_ran) with the maximum vitrinite reflectance (R_max) allows for the accurate correction of vitrinite reflectance suppression induced by anisotropy. However, as its anisotropy intensifies, vitrinite exhibits increasingly complex optical properties, rendering it challenging to reflect the thermal metamorphic temperature of vitrinite using R_max. Methods This study investigated the strongly anisotropic vitrinite in coals and natural coke subjected to magma intrusion in the Shitai coal mine, Huaibei City, Anhui Province. Using a reflected-polarized light microscope (R-PLM), an …

A Cutting Trajectory Planning Technology Driven By Coal Seam Data In A Comprehensive Mining Face, Guo Yifeng, Xue Xusheng, Ma Hongwei, Zhang Guangming, Su Hao, Qi Ailing, Nie Zhen, Ma Kexiang, Wu Xuefei

Coal Geology & Exploration

Objective Currently, the insufficient full-element digitization and the prevalence of “data silos” in fully mechanized mining faces (FMMF) result in poor cutting precision and operational instability of shearers under complex undulating and abrupt geological conditions. These factors pose significant challenges to high-precision proactive trajectory planning. Methods Guided by the academic philosophy that “mining is data acquisition”, this paper proposes a coal seam data-driven cutting trajectory planning method for FMMFs. It elaborates on three core technologies: high-precision digital coal seam modeling, generative model updating and digital twin construction, and data-driven trajectory planning.To address low modeling precision, an intelligent interpolation-based digital coal …

Draft Uniform Federal Policyquality Assurance Project Plan Addendum, Hydrogeologic, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Conditional Approval Letter For Diggings East 95 % Remedial Design Package Submittal (Dated March 25, 2006), The Silver Bow Creek Conservation Area (Sbcca) – 95 Percent Programmatic Technical Specifications Submittal (Dated March 25, 2026), The Butte Priority Soils Operable Unit (Bpsou) Sbcca Operations And Maintenance (O&M) Plan (Dated March 24, 2026), And The Sbcca Final Principles For A Greener Cleanup Report (Dated February 4, 2026), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Draft Final Butte Priority Soils Operable Unit Unreclaimed Sites: Ur-03 Construction Completion Report, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Comment Letter For The Silver Bow Creek/Butte Area Npl Site Butte Priority Soils Operable Unit, 60% Remedial Design Documents For The Blacktail Creek Area Groundwater Hydraulic Control System (Dated March 2, 2026), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Real And Perceived Barriers To Effective Use Of Cataract Surgical Supplies, Caitlin Davie, Lindsay K. Cloud, Scott Burris, Shaina Shiwdin, Brooke Sherry, Christina R. Prescott, Joel Schuman, David Palmer, David Chang, Daniel Parra, Cordelia Kwon, Margaret A. Tharp, Cassandra L. Thiel

Wills Eye Hospital Papers

INTRODUCTION: Cataract surgery, among the most common procedures worldwide, significantly contributes to climate change through both solid waste and air pollution, highlighting the urgent need for targeted interventions. Implementation faces hurdles including legal constraints and concerns about infection risks and malpractice.

METHODS: This article examines federal and state regulatory structures around two key waste reduction strategies: reduction of multidose medications and distribution of partly-used operating room medication to patients post-surgery.

RESULTS: We find little-to-no legitimate regulatory barriers to either waste reduction practice. Dispensing and redistributing partly-used medication has been codified in law in some states. Evidence-based reports indicate minimal risks …

Image Processing Technique To Find The Burden Rock Velocity And Its Interdependency On Bench Blasting Parameters – A Case Study, Channabassamma N, Akhil Avchar, Sahas V Swamy, Vedala Rama Sastry, Hemant Agrawale

Journal of Sustainable Mining

In any rock engineering or excavation project, optimizing blast design is essential for controlling post-blast phenomena such as flyrock, burden throw, and burden rock velocity (BRV). This study investigates the dynamic response of BRV in bench blasting operations by employing a high-speed camera and ProAnalyst software to quantify rock displacement. The relationships between BRV and key blast parameters, number of holes (NH), explosive charge per hole (EPH), total explosive charge (TEC), stiffness ratio (K), and stemming ratio (STR), were analyzed to identify linear or non-linear trends. Non-linear trends, …

Dimensionless Ratios And Processes Controlling Volumetric Bioretention Performance, Andrew Charles Hiestand

Master's Theses (2009 -)

Urbanization of previously natural land cover has spurred the innovation and implementation of green stormwater infrastructure (GSI) to combat increased surface runoff due to impermeable areas and a changing climate. Bioretention has been a popular choice in design due to its small footprint and proven effectiveness in retaining stormwater runoff and limiting discharges to receiving surface waters. However, their event-to-event performance variability is difficult to explain due to a number of confounding and interacting influences that distort cross-site analyses including inter-event drying and antecedent soil moisture conditions, geometric size and media properties, and event magnitude. This study applies and evaluates …

Evaluating Sand Characteristics And Their Influence On Sea Turtle Nest Incubation Conditions, Thomas Naylor

Honors Theses

The embryonic development of sea turtles is strongly influenced by the environmental factors experienced during incubation within the nest. These environmental factors can influence hatchling sex ratios, body condition, and their success emerging from nests. Adult female sea turtles lay nests across a range of sites throughout the nesting season, resulting in each nest encountering unique abiotic conditions. This study aims to identify how variation in sand characteristics, such as grain size proportions, permeability, and color, influences nest temperature and subsequent hatchling outcomes of Loggerhead Sea Turtles (Caretta caretta) and Green Sea Turtles (Chelonia mydas) from …