Earth Sciences Commons^™

Development And Application Of The Sinkhole Hazard Risk Index To Inform Karst Policy And Mitigation Planning, Meghan Puente

Masters Theses & Specialist Projects

Sinkholes are geologic hazards that occur in karst landscapes and can be highly destructive and costly. Sinkhole mitigation plans and development policies are nonexistent at the federal level within the United States and vary significantly at the state level. The lack of a unified standard for sinkhole mitigation planning is partly due to a lack of available data and resources needed to assess sinkhole risk. While there are established sinkhole assessments within the literature, they focus more on the detection and prediction of sinkholes rather than a holistic approach to risk assessment. The goal of this study is to create …

Landuse And Microplastic Transport In Karst Groundwater Of South-Central Kentucky, Katie Norman

Masters Theses & Specialist Projects

Groundwater in karst areas is susceptible to contamination from various sources of pollution. Microplastics are a prevalent source of pollution entering groundwater. This study examines karst groundwater in three areas of investigation. One point of interest is an area that is impacted by urban activities, the Lost River Groundwater Basin, which includes water drainage from the City of Bowling Green, Kentucky. Another study location is Great Onyx (GO) Spring, which is a part of the Great Onyx Groundwater Basin located in Mammoth Cave National Park, Kentucky, and that is relatively unimpacted by urban activities. The third point of interest is …

Developing A Controlled Traffic (Tramline) Farming System, Department Of Primary Industries And Regional Development, Western Australia

Grains and other field crops factsheets

Controlled traffic farming (CTF) is a farming system built on permanent wheel tracks where the crop zone and traffic lanes are permanently separated. It can improve profitability and sustainability.

Implements for seeding, spraying, spreading and harvesting have a particular span, or multiple of it, and all wheel tracks are confined to specific traffic lanes.

CTF increases profit by more yield, better grain quality, improved operation timeliness, and reduced costs. The environment can improve, with less nutrient leaching, less water erosion, better water infiltration, and less greenhouse gas emission. Implementation needs a clear, long-term plan, and prioritisation of soil health.

Another …

Transformation Of Organic To Inorganic Nitrogen In Nh4 +-Illite-Bearing And Ga-Al-Ree-Rich Bituminous Coals: Evidence From Nitrogen Isotopes And Functionalities, Qian Wang, Shifeng Dai, Victor P. Nechaev, David French, Ian Graham, Lei Zhao, Shaowei Zhang, Yang Liang, James C. Hower

Earth and Environmental Sciences Faculty Publications

Nitrogen is one of the most important elements and mainly occurs as organic forms in coal, and in a few cases, in an inorganic form. Organic nitrogen in coal is mainly derived from the proteins of plants and micro-organisms but sources of inorganic nitrogen remain controversial. One hypothesis for the source of inorganic nitrogen is the organic matter of coal, but this lacks strong evidence. In the Daqingshan Coalfield of Inner Mongolia, northern China, an igneous intrusion in the east of the coalfield led to a coal rank increase from the Hailiushu through the Datanhao mines to the Adaohai mine …

Fine-Scale Mangrove Species Classification Based On Uav Multispectral And Hyperspectral Remote Sensing Using Machine Learning, Yuanzheng Yang, Zhouju Meng, Jiaxing Zu, Wenhua Cai, Jiali Wang, Hongxin Su, Jian Yang

Earth and Environmental Sciences Faculty Publications

Mangrove ecosystems play an irreplaceable role in coastal environments by providing essential ecosystem services. Diverse mangrove species have different functions due to their morpho- logical and physiological characteristics. A precise spatial distribution map of mangrove species is therefore crucial for biodiversity maintenance and environmental conservation of coastal ecosystems. Traditional satellite data are limited in fine-scale mangrove species classification due to low spatial resolution and less spectral information. This study employed unmanned aerial vehicle (UAV) technology to acquire high-resolution multispectral and hyperspectral mangrove forest imagery in Guangxi, China. We leveraged advanced algorithms, including RFE-RF for feature selection and machine learning models …

Characterizing Groundwater Flow Across The Barrier Island-High Marsh Interface, Dean Michael Wrobel

Electronic Theses and Dissertations

The freshwater resources of barrier islands are influenced by a variety of hydrogeologic factors, which create unique regions of groundwater composition. Factors including evapotranspiration, geologic constraints, tidal forcing, and meteoric inputs influence subterranean flow creating a groundwater salinity gradient throughout the island-marsh setting which directly influences the spatial distribution of dominant vegetation on the island. Rising sea levels and variation in local climate may alter the hydrologic balance on barrier islands, potentially shifting salinity gradients and ecological baselines on short timescales. The intrusion of saltwater into the barrier island freshwater system could result in the shifting of ecotones and potential …

Applying Circuit Theory To Describe Changes In Structural Landscape Connectivity In Response To Wildfire, Christian Ross Nielsen

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

Understanding and conserving ecological connectivity is critical to the preservation of vulnerable landscapes. Circuit theory, in which landscapes are imagined as circuit boards with varying resistances to the flow of current, is being increasingly used to model spatially explicit connectivity of landscapes and to inform land management and conservation decision-making. Utilizing continuous, quantitative estimates of percent cover by five land cover functional groups to create a conductance surface, this study expanded upon an established application of circuit theory that used the open-source software Circuitscape to model species-agnostic, omnidirectional connectivity. This model was automated using Python to create time-series connectivity maps …

Occurrence, Inputs, And Ecological Significance Of Antibiotics And Pharmaceuticals In Western Nebraska Streams, Katelyn F. Glause

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

Few emerging environmental contaminants are as concerning as antibiotics. Human and animal health benefits greatly from the prudent use of antibiotics, yet we give little thought to environmental release of these biologically active compounds. Environmental occurrence of these and other pharmaceutical compounds must be measured in different environmental compartments such as municipal wastewater and in the vicinity of large animal feeding operations to understand potential effects. This study reports the results of a monitoring study in western Nebraska, with a large population of livestock and smaller but more concentrated population of humans, comparing the relative environmental concentrations and loading from …

Analysis Of Drought-Flood Abrupt Alternation Events And Their Impacts In Kenya, Betty Makena

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

Drought-Flood Abrupt Alternation (DFAA) is a compound disaster event that refers to the abrupt shift of extreme drought events to extreme floods resulting in exacerbated impacts on already vulnerable communities and hindering their coping abilities. This study aimed to analyze drought-flood abrupt alternation events and their impacts in Kenya. The first chapter aimed to understand historical drought events in the Greater Horn of Africa and their impacts, while drawing comparisons with the recent 2020-2022 drought period, referred to as the ‘triple dip La Niña’. Datasets used in this study include the Climate Hazards Group InfraRed Precipitation with Station (CHIRPS), Normalized …

Remotely Sensed Early Warning Of Algal Blooms In An Eastern Nebraska Reservoir: A Comparison Of Temporal And Spatial Indicators, Mercy Kipenda

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

Cyanobacterial harmful algal blooms (CyanoHABs) detrimentally affect human, animal, and ecosystem health. Remotely sensed early warning systems for cyanoHABs in inland lakes could contribute to more proactive water quality monitoring and help mitigate negative impacts. Advances in freely available remote sensing imagery, with finer spatial, temporal, and spectral resolutions, present new opportunities for the development and comparative analysis of methods to detect sudden deterioration in lake water quality. In this thesis, I compared and tested for temporal and spatial early warning signals of cyanoHABs in field-based and remotely sensed datasets from 2019 to 2023 in Pawnee Lake in southeast Nebraska, …

Impacts Of Invasive Carp And Their Population Dynamics On Fish Communities In The Missouri River, Joshua F. Kocik

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

Invasive Carp species: Silver Carp Hypophthalmichthys molitrix, Bighead Carp Hypophthalmichthys nobilis, Grass Carp Ctenopharyngodon idella, and Black Carp Mylopharyngodon piceus have both potential and realized abilities to negatively impact native species. Specifically, Bighead Carp and Silver Carp as filter feeders have been theorized to be detrimental not only to adult filter-feeding species, but to many fish which rely on plankton and algae in their early-life stages. The impact of Invasive Carp on the overall fish community remains underexplored. The fish communities below Gavins Point Dam (Invasive Carp present) and Fort Randall Dam (Invasive Carp absent) afford the …

Spatiotemporal Plasticity In Reproductive Readiness And Recruitment Of Ichthyoplankton Of Invasive Silver Carp Along A Western Invasion Front, Jessi L. Urichich

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

Individuals of invasive species at the edge of their invasion distribution may exhibit enhanced reproductive capacity and phenotypic plasticity leading to accelerated range expansion. Environmental conditions in highly fluctuating environments at distribution edges may either promote or hinder such reproductive readiness and phenotypic plasticity. Dynamic habitat conditions and periodic disturbances experienced in prairie streams, such as drought (e.g., low-flow, high water temperatures), may potentially reduce suitable spawning environments and ichthyoplankton recruitment of invasive Silver Carp, potentially slowing range expansion or enabling management strategies that reduce abundance in the absence of a reproducing population. Female Silver Carp batch fecundity, Gonadosomatic Index …

Assessing, Restoring, And Centering Social–Ecological Relationships For Advancing Social–Ecological Resilience In The Northern Great Plains Grasslands, Katia Pilar Carranza Bernal

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

The Northern Great Plains grasslands are social-ecological systems that were shaped by evolutionary and Indigenous social-ecological relationships. European colonization disrupted many of these interactions, including the coupling of fire and grazing, and degraded social-ecological resilience, shifting these grasslands to a new state. For those reasons, my research focused on assessing, restoring, and centering evolutionary and Indigenous social-ecological relationships for advancing social-ecological resilience in the Northern Great Plains grasslands. I first performed a study in the Nebraska Sandhillls assessing the potential of patch-burn grazing to support grassland resilience by comparing its effects to those of rotational grazing. Through vegetation and bird …

Diatom-Inferred Hydroclimate Variability In Marl Lake, Wi Over The Past ~2050 Years, Christian E. Sizemore

All-Inclusive List of Electronic Theses and Dissertations

Hydroclimate variability in the Midwest has increased over the past few decades, as as evidenced by increases in average precipitation and frequency of extreme hydroclimate events. Understanding natural climate variability in this region will help communities in the Midwest to better prepare and mitigate the risks associated with extreme hydroclimate variability in the future. Natural lakes in the Midwest are often effective archives of hydroclimate; many have been shown to respond directly to changes in climate both locally and regionally. We extracted a 4.5-meter sediment core, representing approximately 2050 years of sediment accumulation, from the deepest part of Marl Lake …

Coal Creek Carbon Capture, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about Coal Creek Carbon Capture project, a CarbonSAFE initiative. The Coal Creek Carbon Capture project is investigating the feasibility of developing safe, permanent geologic storage of CO₂ captured from Coal Creek Station.

Robust Hydropower Planning Balances Energy Generation, Carbon Emissions And Sediment Connectivity In The Mekong River Basin, M. Tangi, Rafael Schmitt, Rafael M. Almeida, S. Bossi, Alexander S. Flecker, F. Sala, A. Castelletti

School of Earth, Environmental, & Marine Sciences Faculty Publications

We present a framework for strategic dam planning under uncertainty, which includes GHG emissions mitigation as a novel objective. We focus on the Mekong River Basin, a fast‐developing region heavily relying on river‐derived ecosystem services. We employ a multi‐objective evolutionary algorithm to identify strategic dam portfolios for different hydropower expansion targets, using process‐related and statistical models to derive indicators of sediment supply disruption and GHG emissions. We introduce a robust optimization approach that explores variations in optimal portfolio compositions for more than 5,000 state‐of‐ the‐world configurations, regarding sediment origins and trapping and GHG emissions. Thus, we can rank dam projects' …

Effects Of Climate Change On (Semi)-Arid Ecosystems In The Southwestern United States, Charlotte Van Der Nagel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Climate change is considered amongst the most severe threats to terrestrial and aquatic ecosystems globally. Ecosystems in the southwestern United States have specifically been impacted by intense drought conditions since 2000. Higher temperatures combined with altered precipitation stresses many ecosystems; however, ecosystem specific responses to such stressors may vary. Here, the effects of climate change on semi-arid ecosystems are analyzed for some of the most vulnerable ecosystems in the southwestern United States: lacustrine, riparian, and dryland ecosystems.

Lakes and reservoirs in arid environments often serve as drinking water sources and recreational areas where high water quality is essential. Climate change …

Integration Of Matlab And Machine Learning To Accelerate Evaluation Of Biological Activity In Agricultural Soils And Promote Soil Health Improvement Goals, Andrew Stiven Ortiz Balsero

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

Traditionally, assessments of soil biological activity have been confined to laboratory settings, creating a disconnect with practical in-field methods. To bridge this gap, cotton fabric degradation has been used to illustrate soil microbial activity under different management practices. While effective, these demonstrations are subjective and labor-intensive.

Researchers have explored using image processing software like ImageJ and Adobe Photoshop to streamline this process. Although these tools accurately quantified fabric degradation under varying soil conditions, the methods remained labor-intensive and complex. Consequently, these methods were still not ideal for on-farm use by agricultural practitioners.

To further address labor and complexity limitations, the …

Transferred Benefits In Inter-Community Beach Nourishment: A Field Study On Efficiency, Owen Thomas

Theses, Dissertations and Culminating Projects

To combat the effects of relative sea level rise and the natural erosional processes affecting the sandy, diffusive beaches of New Jersey, most communities utilize beach nourishment to stabilize their beaches. Beach nourishment, the practice of artificially widening the beach berm with sand from other areas, not only stabilizes beaches but also protects oceanfront homes from storm surges, while adding recreational space and tourism value. These benefits are reflected in increased property values, most notably in oceanfront properties. The diffusive nature of these beaches, however, means that individual nourishment events are inherently shared with neighboring communities as sand is readily …

Onset Of Antarctic Glaciation At The Eocene-Oligocene Transition In The Weddell Sea And Its Impact On Ocean Circulation, Victoria Hojnacki

Theses, Dissertations and Culminating Projects

The Eocene – Oligocene Transition (EOT) (34 Ma) represents a greenhouse to icehouse climate transition that is marked by the appearance of permanent ice sheets in Antarctica. Studying this period of climate change allows us to understand how different Earth systems reacted under changing atmospheric CO₂ conditions. Though the timing of the development of the East Antarctic Ice Sheet is well supported, the development of the West Antarctic Ice Sheet is still up for debate. Ocean Drilling Program Site 696 is the only paleoarchive of the EOT in the Weddell Sea region and offers an opportunity to better constrain the …

Evaluation Of Future Sea-Level Impacts Using A Sharp Interface Saltwater Intrusion Model, Caroline Hiott

All Theses

Saltwater intrusion is a growing problem that is being exacerbated by climate change. Saltwater intrusion is the process by which saltwater moves towards freshwater supplies driven by saltwater’s greater density compared to freshwater. Saltwater intrusion can contribute to the salinization of freshwater resources, degradation of underground storage tanks, communication systems, and pipelines, as well as lead to groundwater flooding (Ketabchi et al., 2016). Numerical modeling can be used to simulate saltwater intrusion along coastal areas. One of the more computationally efficient modeling tools is the sharp interface approach, SWI2, that is a part of the MODFLOW 2005 suite (Werner et …

Upscaling Sapflow Measurements To Footprint Transpiration Estimations In The Jornada Experimental Range, New Mexico, Usa, Habibur R. Howlider

Open Access Theses & Dissertations

This study proposes a new method for computing transpiration across an eddy covariance footprint using field observations of plant sap flow, phytomorphology sampling, uncrewed aerial system (UAS) digital image processing, and eddy covariance micrometeorological measurements. The method is applied to the Jornada Experimental Range, New Mexico where we address three key questions: (1) How do daily summer transpiration rates of Mesquite (Prosopis glandulosa) and Creosote (Larrea tridentate) individuals of different ages compare? (2) How can the contributions of plants of varying sizes and ages be integrated for terrain-wide transpiration estimates? (3) What is the contribution of transpiration to total evapotranspiration …

Pyrolysis Characteristics And Pore-Fracture Evolutionary Patterns Of Tar-Rich Coals, Geng Jishi, Wang Shuangming, Sun Qiang, Hou Enke, Yang Yuru, Hu Xin, Xue Shengze

Coal Geology & Exploration

Objective Extracting coal-based oil and gas from tar-rich coal through in situ pyrolysis plays a significant role in counteracting the shortage of China's oil and gas resources and enhancing the utilization efficiency of coal resources, representing a new trend for the efficient exploitation of tar-rich coals. During the in situ pyrolysis of tar-rich coals, the internal heat transfer, as well as the migration and production of pyrolysis products, is directly influenced by the oil and gas production characteristics and the characteristics of pores and fractures. Hence, it is particularly critical to identify the pyrolysis characteristics and pore-fracture evolutionary patterns of …

In-Situ Pyrolysis Of Tar-Rich Coal: Effects On Geological Environments And Geological Guarantee Technology, Xu Shiang, Zhang Pingsong, Cheng Gang, Wu Haibo

Coal Geology & Exploration

Objective Tar-rich coal, a type of unique unconventional oil and gas resource that integrates coal, oil, and gas, can be transformed into tar, combustible gases, and semi-coke solid fuels with high added value through in-situ pyrolysis. Therefore, the in-situ pyrolysis of tar-rich coal has the potential to meet the challenges in achieving the green exploitation and clean, low-carbon utilization of coals in the traditional coal industry. Furthermore, in terms of how to reduce coal pollution emissions and enhance energy efficiency, this technology offers a new solution for attaining the goals of peak carbon dioxide emissions and carbon neutrality. It also …

Pilot Experiment For Underground In-Situ Pyrolysis Of Tar-Rich Coal In The Northern Shaanxi Province, Duan Zhonghui, Yang Fu, Wang Zhendong, Ma Li, Duan Xiaoqing, Cao Husheng, Chen Liang

Coal Geology & Exploration

Objective The breakthrough of the pilot experiment for underground in-situ pyrolysis of tar-rich coal in the northern Shaanxi has added new vitality to the research on in-situ conversion of fossil energy such as tar-rich coal and oil shale, and the results have attracted wide attention both inside and outside the industry. The research on underground in-situ pyrolysis of tar rich coal is still in its infancy, lacking systematic research on field engineering data.Methods Based on the pilot experiment, the main geological conditions and engineering difficulties have been clarified, and the progress of underground in-situ pyrolysis has been summarized. The …

Geological Factors Controlling The Occurrence Of Carboniferous-Permian Tar-Rich Coals In The Ningdong Coalfield, Huang Pengcheng, Guo Weiyong, Ji Xiaoyan, Cai Feifei, Zhang Zhifeng, Huang Kang, Cheng Yunqiang, Liu Zheng, Wang Bei, Chen Rong, Shi Qingmin

Coal Geology & Exploration

Objective The Ningdong Coalfield of the Ordos Basin boasts abundant tar-rich coal resources, of which tar-rich coals in the Carboniferous-Permian coal seams exhibit unique occurrence characteristics due to differences in thermal evolution and sedimentary environments. Methods This study analyzed the occurrence characteristics and critical material composition of tar-rich coals in the Hongdunzi and Siguquan mining areas. Based on this, it explored the controlling effects of the degree of coalification and sedimentary environment on the tar yield. Results and Conclusions The results indicate that the Carboniferous-Permian coal seams in the Ningdong Coalfield exhibit average tar yields ranging from 7.15% to 11.07%, …

Distributions Of Products From The Pyrolysis Of Tar-Rich Coals For Tar Extraction In Northern Shaanxi Province, China, Yu Zunyi, Guo Wei, Yang Panxi, Gao Kun, Yang Fu, Ma Li, Wang Jing, Li Hongqiang, Yang Bolun, Wu Zhiqiang

Coal Geology & Exploration

Objective Tar-rich coals stand as a special type of coal resource that integrates coal, oil, and gas properties. These coals, boasting abundant hydrogen-rich structures such as side chains and bridge bonds with aliphatic structures, are prone to crack and produce tar and gas during pyrolysis. These establish tar-rich coals as ideal raw materials that produce oil and gas through thermal conversion. Presently, the research into tar extraction from tar-rich coals through pyrolysis remains in its initial stage, and exploring the impacts of technological conditions, including heat carrier, heating type, and pyrolysis temperature, on the pyrolysis process holds critical significance for …

Simulation Of The Pyrolysis Process Of Tar-Rich Coals In An H2O Atmosphere Based On The Reactive Force Field Molecular Dynamics, Huang Zibo, Liu Qianru, Liu Hong, Zhou Wenjing, Wei Jinjia

Coal Geology & Exploration

Objective Tar-rich coal resources, abundant in China, can be converted into energy products (e.g., chemicals and gas/liquid fuels) through pyrolysis, thus alleviating the country’s dependence on oil and gas imports. A thorough understanding of the product evolution and reaction mechanisms of the pyrolysis of tar-rich coals is crucial to research into the clean and efficient conversion processes of coals. Methods Based on the reactive force field molecular dynamics (ReaxFF MD), this study simulated the pyrolysis process of tar-rich coals (long-flame coals) and explored the impacts of the H₂O atmosphere on the distribution of pyrolytic products, along with the …

Spatiotemporal Distributions Of Typical Contaminants From The In-Situ Pyrolysis Of Tar-Rich Coals, Tian Hua, Zhang Ruolin, Wang Qianji, Wu Xiaoyu, Zhang Lei, Zhang Lingru, Fang Siyuan

Coal Geology & Exploration

Objective and Methods Under high temperatures, oil and gas produced from the in situ pyrolysis of tar-rich coals will migrate toward and accumulate in the overburden strata after passing through the fracture zones on the coal seam roof, causing potential contamination risks for the underground environment. To understand the release and distribution characteristics of typical contaminants generated from the underground pyrolysis of tar-rich coals, this study investigated the typical tar-rich coals from the Shenfu mining area of the Jurassic coalfield in northern Shaanxi Province. Based on data on the stratigraphic structures and lithology and using the self-developed equipment for similarity …

Downhole Heaters For In-Situ Pyrolysis Of Tar-Rich Coals：A Review And Prospects, Wang Zhendong, Duan Zhonghui, Yang Fu, Ma Li

Coal Geology & Exploration

Significance China boasts abundant tar-rich coal resources, which prove to be potential coal-based oil and gas resources capable of ensuring China's energy security. Extracting hydrogen while preserving carbon through the in-situ pyrolysis of tar-rich coals has developed into a trend in the clean and low-carbon utilization of coal resources. Downhole heaters serve as critical equipment for the efficient in-situ pyrolysis of tar-rich coals. Advances Based on investigations and the systematic collection of relevant information and data, this study offers a brief introduction of the currently used methods for in-situ convection heating, focusing on the present situation of the research and …