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A Cylindrical Permeation And Diffusion Model For Bingham Grout In Water-Rich Sand Layers And Its Experimental Research, Wang Xuesong, Cheng Hua, Yao Zhishu, Rong Chuanxin, Xie Bao

Coal Geology & Exploration

Objective The disaster prevention and control for water-rich sand layers pose a major challenge to the safe construction of tunnels and deep foundation pits. Typically, the impermeability and bearing capacity of highly water-rich and weakly cemented sand layers are enhanced through permeation grouting via sleeve valve tubes, with resulting grouting concretions being approximately cylindrical. Methods To explore the cylindrical diffusion mechanism of permeation grouting in sand layers, this study constructed a cylindrical diffusion model of radial tube flow for the permeation grouting of Bingham grout in sand layers while considering the tortuosity effects. Subsequently, this study developed a set of …

Production Characteristics Of Deep Coalbed Methane Wells In The Linxing Block And Associated Their Influencing Factors, Wang Zhizhuang, Wu Peng, Sun Qiang, Liu Rui, Wang Lingbo

Coal Geology & Exploration

Objective The production characteristics of deep coalbed methane (CBM) are significantly distinguished from those of middle-shallow CBM, and even the production wells of deep CBM within the same block exhibit different characteristics. Given that relevant research remains in its exploratory stage, gaining a deeper understanding of the factors influencing the differences in production characteristics of deep CBM is significant for the production capacity prediction and production management of the subsequent large-scale production stage. Methods To determine the production characteristics of deep CBM in the Linxing block and their influencing factors, this study examined geological engineering factors including gas content, coal …

Pore Structure And Differential Fluid Occurrence Of Deep Coal Seams, Wu Jian, Sun Qiang, Shi Xuefeng, Gao Lijun

Coal Geology & Exploration

Objective Breakthroughs have been achieved in deep coalbed methane (CBM) exploration along the eastern margin of the Ordos Basin, exhibiting the characteristics of local breakthroughs but regional differential CBM production in multiple blocks. The pores and fractures in deep coal reservoirs, serving as the material spaces for fluid occurrence and occurrence, are critical to the differential development across deep CBM blocks. Methods In this study, coal samples were collected systematically from the deep part of the Shenfu block located along the eastern margin of the Ordos Basin. Using conventional tests on porosity, permeability, and physical properties, as well as CO …

Technology For Efficient Production Of Deep Coalbed Methane In The Shenfu Block, Li Bin, Yang Fan, Zhang Hongjie, Feng Lei, An Qi, Hao Zhaobing

Coal Geology & Exploration

Objective Deep coalbed methane (CBM), representing one crucial resource successor for ensuring the oil and gas security of China and achieving peak carbon dioxide emissions and carbon neutrality of the country, exhibits broad prospects for production. However, due to the small low universality of CBM production technologies under varying geological conditions, a technology that has been successfully applied in some blocks cannot be directly extended to other blocks. This leads to blind deployment of well types and well patterns in the early-stage exploration and development of new blocks to a certain extent. Given this, it is necessary to develop a …

Coastal Sedimentary Records Of Extreme Events And Human Activity: Examples From Hurricanes And Microplastics, Nicholas T. Culligan

LSU Doctoral Dissertations

Coastal regions are uniquely vulnerable to a myriad of natural and anthropogenically caused stresses such as hurricane strikes and chronic microplastic pollution. Both hurricanes and microplastics have major negative effects on global coastlines and are forecast to become more damaging in the future. However, current model trends are based on limited modern data and may not provide an accurate or comprehensive view of the future. Therefore, this dissertation investigates coastal stratigraphic records to determine long-term past trends of these presses and pulses so that researchers, stakeholders, and policy makers can use them to enact strategies to mitigate damages from worsening …

Chinese Tallow Long-Term Impact On Stand Dynamics In A Bottomland Hardwood Forest Following Vegetation Management, Nicklaus R. Langlois

Electronic Theses and Dissertations

Chinese tallow (Triadica sebifera (L.) Small) is an invasive tree known to have negative impacts on bottomland hardwood forests. Chinese tallow is proficient in reproducing and surviving in bottomland hardwood forests because it is more flood and shade tolerant than most native trees. The long-term effectiveness of Chinese tallow control is an important topic to research as only a few long-term studies of Chinese tallow control have been conducted. A 10-year re-measurement of 22 paired plots installed in 2012 on the Pineywoods Mitigation Bank near Diboll, Texas following herbicide treatments examined Chinese tallow and native tree stand structure. Each …

Charlotte: A Modern Tool For Cave Surveying, Luca Tringali Mr., Giacomo Canciani Dr., Alexander Debenjak, Tecla Tripari

International Journal of Speleology

The future of cave surveying is a full 3D scan, as automatic as possible, capturing all morphologically relevant details. However, the vast majority of cavers are still using tools designed more than 15 years ago. The advancements in tools for architects, CAD designers, programmers of VR and robotics could be helpful also for the caving community. That’s why Charlotte, a cheap DIY 2.5D scanner designed for cave surveying, was developed and built. To demonstrate its capabilities, a new survey of Grotta Regina del Carso cave (cad. nr. 2328/4760VG), the biggest cave in the Gorizia Karst, has been realized and published. …

A ‘Nuclear Bomb’ Or Just ‘A Joke’? Groundwater Models May Help Communicate Nuanced Risks To The Great Salt Lake, Matthew D. Laplante, Piyush Dahal, Shih-Yu Simon Wang, Kirsti Hakala, Avik Mukherjee

Plants, Soils, and Climate Faculty Publications

The Great Salt Lake entered the zeitgeist of environmental concern in 2022 when a coalition of scientists and activists warned in a highly publicized report that the lake might be just five years away from complete desiccation, a possibility one state official warned was tantamount to an “environmental nuclear bomb”. Shortly thereafter, an unpredicted and unprecedented pluvial winter resulted in an increase in inflow, temporarily halting the lake’s decline and prompting Utah’s governor to mock the dire prediction as “a joke”, an outcome that speaks to the tension between agenda-setting and trust-building that researchers face when sharing worst-case warnings, particularly …

Influence Of Phosphate And Boron Addition To Mixed Liquid Fertilizer On The Growth And Yield Of Red Chili Cultivated In The Subsoil Layer, Stefina Liana Sari, Emma Trinurani Sofyan, Anni Yuniarti

Jurnal Kultivasi

This study assesses the impact of adding phosphate and boron in a mixed liquid fertilizer (MLF) on the growth and yield of red chili plants cultivated in a subsoil environment. The experiment was conducted to comprehend how these nutrients affect the performance of red chili plants, particularly when cultivated in less ideal conditions such as subsoil, a remnant of excavation for brick production. The research was carried out at the Ciparanje Garden of the Faculty of Agriculture, Universitas Padjadjaran. The research design employed a Randomized Completely Block Design with the following treatments: A = Control (degraded soil without fertilizer), B …

Germplasm Collecting By Iger: The Future, N R. Sackville Hamilton, K H. Chorlton, I D. Thomas, M D. Hayward

IGC Proceedings (1977-2023)

This paper will present novel approaches being implemented or planned lo improve future collections for forage germplasm, and to deal with changing priorities, with particular reference to Lolium perenne. With a large number of accessions already in the gene bank and providing a wide range of genes for possible utilisation, future collections must be targeted ever more precisely, The principle object is to acquire novel genes not already present in the gene bank, to maximise the proportion of genes in the gene pool of L. perenne that is held in the gene bank. A subsidiary object, to support not …

Inverted "T" Drill Openers For Pasture Establishment By Conservation Tillage, C J. Baker, M A. Choudhary, K E. Saxton

IGC Proceedings (1977-2023)

No-tillage is an increasingly acceptable practice for pasture renewal in New Zealand. Seeding and fertilising are the most difficult operations to consistently perform well in a residue-covered surface for establishment of subsequent pastures and crops. Two new seed drill openers for seed and fertiliser placement in conservation tillage are described. These openers, developed in New Zealand and tested extensively ln NZ, USA, Canada and Australia, create an inverted "T-shaped" slot, One version uses a single winged tine while the other version uses a single disk running straight ahead against which 2 winged side blades rub. They raise the soil for …

Implications And Improvements In Nutritive Value On Plant Performance And Grassland Management, D Clark, J R. Wilson

IGC Proceedings (1977-2023)

Lignin modification is one method of improving plant nutritive value and is used to illustrate methods and consequences of plant manipulation. The effect of modifying lignin organ, tissue or enzyme levels on plant performance is inferred from recent scientific work on a range of species. Selection for higher whole plant digestibility is sometimes negatively correlated with plant yield. However, there is sufficient variation in both characters that improvement new not inevitably lead to decreased yield. Cultivars selected for low leaf strength or more digestible stems usually have lesser amounts of sclerenchyma and vascular tissue with less lignin and thinner walls. …

Hypogene Speleogenesis In Carbonates By Cooling Hydrothermal Flow: The Case Of Mt. Berenike Caves, Israel, Roi Roded, Boaz Langford, Einat Aharonov, Piotr Szymczak, Micka Ullman, Shemesh Yaaran, Boaz Lazar, Amos Frumkin

International Journal of Speleology

The Berenike hypogenic cave system near Lake Kinneret, Israel, provides a valuable case study for investigating the recently proposed Confined-Cooling-Flow (CCF) speleogenesis model. Field and speleological surveys, along with existing research, are used to provide a thorough analysis. The CCF model relies on a simple thermo-hydro-chemical scenario, involving the rise of CO2-rich hydrothermal fluids discharging into a confined layer. The cooling of these CO2-rich fluids turns them into aggressive solutions due to the inverse relation between temperature and solubility of carbonates (retrograde solubility). Previous geochemical and numerical analyses of the CCF model predict localized and persistent dissolution and speleogenesis on …

From Technology Transfer To Resource Management, Janice Jiggins

IGC Proceedings (1977-2023)

Six models of technological innovation are examined. The implications for the roles and functions of research and extension, and of agricultural education systems, are analysed. The models are assessed against issues of gender, natural resource management and poverty, with consideration of who pays, and who benefits. The conclusion is drawn that the Transfer of Technology model is not a generalisable model to all circumstances, clients and policy goals. Client-driven systems and participatory approaches which build partnerships among researchers, extensionists, producers and other users of grassland landscapes, can be more effective and efficient.

Combining Agricultural Agent Training In Forages With Graduate Credit, Garry Lacefield, Jimmy Henning, M Rasnake, C Forsythe, L Davis

IGC Proceedings (1977-2023)

An intensive agent training programme in alfalfa (Medicago sativa L.) production nnd utilisation was initialed in 1990. The training was organised by slate extension forage specialists to meet the needs of agricultural agents. Previous programmes have offered similar training but did nol resull in graduate credit. This unique approach offered intensive training to agents presented by a multidisciplinary learn of scientists. All requirements for graduate credit were met and the course completion resulted in 3 hours of graduate credit. The course has been rated "superior" by students. When properly organised and implemented, intensive agent training can be offered that …

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 …

Land-Use Change As A Major Driver For Mid-20th-Century Flood Intensity Reduction In The Southeastern Us, Zhixiong Shen, Nicholas Conway, Shaowu Bao, Samuel Muñoz, Andreas Lang

Marine Science

Land-use changes affect hydrologic processes, but their impact on flooding remains obscure amid increasingly heavy precipitation. Instrumental records are short relative to land-use change history and inadequate for flood attribution studies. Here we integrate a high-resolution paleodischarge record spanning the past ∼200 years from the largest basin in the Southeastern United States with instrumental data and hydrological modeling. We find that the 100 yr flood magnitude for large regional rivers exhibits 50%–75% reductions in the mid-20th century. We attribute at least 50% of the reductions to a regional shift from widespread agricultural land to conservation and reforestation and the rest …

Assessing Soil Properties & Suitability For Optimized Irrigation Development In Sudan, Northern Africa, Suhib O. Hamid

Department of Agricultural and Biological Systems Engineering: Masters Project Reports

In Chapter 1, soil properties essential for efficient irrigation are thoroughly assessed. Factors such as soil texture, infiltration rates, and nutrient content are analyzed to provide insights into the selection of modern irrigation systems. Utilizing data collected from 3,192 locations through GPS and laboratory analyses, alongside sophisticated ranking systems, the research determines the most suitable irrigation methods for specific soil series. Findings highlight the remarkable efficiency of drip irrigation across various soil types, contrasting with the consistently lower performance of surface irrigation. The chapter emphasizes the significance of considering soil variability, evapotranspiration, and investment factors in selecting irrigation methods for …

Environments And Controls Of Erosional Bedforms In Soluble Channels, Ethan W. Oleson

Graduate Theses and Dissertations

Erosional bedforms, such as scallops, preserve valuable information on the paleohydrologic conditions forming soluble channels in karst systems. While these bedforms are commonly used to interpret past conditions, questions about their formation remain. Mathematical models of speleogenesis in turbulent flow predict that the conditions for forming scallops do not occur in natural carbonate systems. However, scallops are readily found in caves throughout the world. This conundrum has several possible resolutions, but each lacks field-based observations. We present a field-based study of the environments and controls of scallops in gypsum, limestone, and dolostone caves. Our results are based on field observation, …

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 …

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 …

Using Raman Spectroscopy To Validate Metamorphic P-T Paths From Western New Hampshire, Alexis Thomas

Boise State University Theses and Dissertations

Constructing and interpreting pressure-temperature (P-T) paths in metamorphic rocks is crucial to understanding tectonic processes occurring at mid- to deep-crustal levels. Conventional methods for obtaining P-T paths rely on mineral chemistry, such as chemical zoning in garnets, which assumes growth at chemical equilibrium. However, studies show that garnet growth can occur with disequilibrium nucleation, which can result in a biased or potentially incorrect P-T path. An alternative, physics-based approach using Raman spectroscopy can also be used to determine P-T paths. This method involves using elastic thermobarometry of quartz inclusions within garnet. In this study, I tested the hypothesis that P-T …

Exploring Overbank Sediment Deposition Variation In Heavily Modified Floodplains Of The Lower Mississippi River: A Sedimentological And Geophysical Analysis, Seth Fradella

Master's Theses

Since the 1930s, the Lower Mississippi River (LMR) has experienced large-scale modifications to the channel profile and surrounding floodplains through dams, dikes, revetments, dredging, and channel cutoffs. Although these changes have improved navigation and reduced flood risk, unanticipated changes to the major flood return period, individual flood severity and duration, and sediment regime have become increasingly apparent and sometimes problematic, such as the 2011 and 2018-2020 floods. Flood control levees along the LMR have reduced the natural floodplain area by 70-90%, resulting in heavily restricted overbank storage capacity of water and sediment. For the same flood events in recent history, …

Staying Fresh: Unconventional Approaches Towards Advancing Energy Sustainability, Water Resources, And Community Resiliency In The Southwestern United States, Judith Hoyt

Open Access Theses & Dissertations

This dissertation addresses critical challenges in urban heat management, sustainable energy resource utilization, and water quality communication through three studies. Study 1 investigates the impact of roof color on urban heat islands in Tucson, Arizona where approximately 70% of roofs display high albedo (i.e., light) colors. Energy consumption simulations conducted indicate that converting dark- to light-colored roofs could save Tucson approximately $1,400,000 annually in energy costs, highlighting the potential of cool roofs for energy savings and improved thermal comfort. Study 2 assesses the sources of lithium in subsurface waters in West Texas and South Central New Mexico. Water chemistry data …

Seismic Imaging Of Mcmurdo Ice Shelf Near Williams Airfield, Yeshey Seldon

Open Access Theses & Dissertations

Seismic exploration has played a crucial role in understanding the Earth's interior and has been successfully employed in various regions, including Antarctica. This research focuses on analyzing a 1000-m seismic line on McMurdo Ice Shelf near Williams Airfield, as part of the Thwaites Interdisciplinary Margin Evolution (TIME) project. The McMurdo Ice Shelf, covering an expansive area within the Ross Ice Shelf, has undergone significant changes due to evolving oceanic and atmospheric conditions. The presence of Circumpolar Deep Water (CDW) has recently impacted the ice shelf, with warmer ocean waters causing basal melting and changes in wind patterns affecting ice flow …

Image Processing Techniques For Water Droplet Penetration Time And Contact Angle Estimation, Sai Balaji Jai Kumar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Water droplet behavior on soil surfaces plays a critical role in numerous environmental processes, including soil erosion, hydrological dynamics, and ecosystem health. Accurate characterization of soil water repellency, quantified by parameters such as water droplet penetration time (WDPT) and contact angles (WDCA), is essential for informed decision-making in agricultural management, forestry practices, and land-use planning. Despite the significance of these parameters, challenges exist in reliably estimating them due to the complex and dynamic nature of soil-water interactions. This thesis address challenges in estimating WDPT and WDCA, by leveraging state-of-the-art image processing techniques and machine learning algorithms. The research focuses on …

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 …

Shedding Light On Past Ice-Free Intervals In Northwest Greenland: Luminescence Dating Of The Base Of The Camp Century Ice Core, Hawke Woznick

All Graduate Theses and Dissertations, Fall 2023 to Present

The goal of this thesis is to provide greater resolution on the age and character of the subglacial sediment recovered from the base of the Camp Century ice core, northwestern Greenland. Geochemical analysis indicated that the upper sub-ice sediments were geochemically different and experienced greater weathering than the basal unit underlying a one-meter silty ice lens. Analysis of feldspars within the very fine sand fraction indicates they are dominated by potassium feldspar. Sediment was dated using luminescence, which provides an age for the last time sediment was exposed to light. Luminescence analysis returned ages around 420 thousand years old, which …