Earth Sciences Commons^™

Initial Microseismic Recordings At The Onset Of Unconventional Hydrocarbon Development In The Rome Trough, Eastern Kentucky, Andrew Holcomb

Theses and Dissertations--Earth and Environmental Sciences

The Cambrian Rogersville Shale is a part of a hydrocarbon system in the Rome Trough of eastern Kentucky and West Virginia that can only be produced unconventionally. In Kentucky, the Rogersville Shale ranges in depth from ~1,800 to ~3,700 m below the surface with the crystalline basement ~1,000 m lower than the formation’s base. Baseline Rome Trough microseismicity data were collected, focusing on wastewater injection wells and recently completed and planned unconventional hydrocarbon test wells in the Rogersville Shale, using thirteen broadband seismic stations installed between June, 2015 and June, 2016 and existing University of Kentucky and central and eastern …

Sedimentary Responses To Growth Fault Slip And Clay Shrink And Swell Induced Elevation Variations: East Matagorda Peninsula, Texas, Wei Ji

Theses and Dissertations--Earth and Environmental Sciences

East Matagorda Peninsula in southwestern Texas is characterized geologically by active, regional-scale and near-surface growth faulting. Decimeter scale (up to 0.42 m) vertical displacement was recorded at the study site over a period of four years, not believed to be associated with growth faulting. This research tested the hypotheses that fault slip rates were correlated with sediment accumulation rates, and that the observed vertical displacement was produced by shrink-and-swell clays in near surface sediments. To quantify sediment accumulation rates, a suite of radionuclides (⁷Be, ¹³⁷Cs, and ²¹⁰Pb) were used. To understand the effects of shrink-and-swell clays, …

Potential Field Modeling Across The Neodymium Line Defining The Paleoproterozoic-Mesoproterozoic Boundary Of The Southeastern Margin Of Laurentia, Rachel Lauren Durham

Theses and Dissertations--Earth and Environmental Sciences

A zone of high magnetization along the SE margin of Paleoproterozoic Laurentia in the United States is indicated by magnetic anomaly data. The SE edge corresponds to the geochemical Neodymium mantle derivation model age (T_DM) boundary and the entire anomaly overlies the Paleoproterozoic Mazatzal Province. Two-dimensional gravity and magnetic models across the Nd boundary are created with Moho constrained from receiver functions with gravity, sedimentary thickness and the base of the crustal magnetization. Upper crustal magnetization does not show strong variation across this boundary and much of the strong magnetization appears to lie in the middle crust. Using …

Fluvial-Lacustrine Processes Shaping The Landforms Of The Distal Paraguay Fluvial Megafan, Edward Limin Lo

Theses and Dissertations--Earth and Environmental Sciences

Tropical wetlands such as the Pantanal help regulate global biogeochemical cycles, but climate change is modifying these environments. Controls on environmental changes can potentially be assessed from ancient, well-dated lacustrine sedimentary records. An integrated field and laboratory approach was undertaken to study the limnogeology of Lake Uberaba in the northern Pantanal, and test whether the lake has preserved a reliable record of environmental change in its strata. This study was designed to understand how the basin accumulates sediment and to assess its sensitivity to hydroclimatic variability. The data showed that modern Lake Uberaba is a highly dynamic, freshwater fluvial-lacustrine basin. …

Effects Of Hydrologic Connectivity And Land Use On Floodplain Sediment Accumulation At The Savannah River Site, South Carolina, Jeremy E. Eddy

Theses and Dissertations--Earth and Environmental Sciences

Floodplains, and the sediment accumulating naturally on them, are important to maintain stream water quality and serve as sinks for organic and inorganic carbon. Newer theories contend that land use and hydrologic connectivity (water-mediated transport of matter, energy, and/or organisms within or between elements of the hydrologic cycle) play important roles in determining sediment accumulation on floodplains. This study hypothesizes that changes in hydrologic connectivity have a greater impact on floodplain sediment accumulation than changes in land use. Nine sediment cores from seven sub-basins were collected from the Savannah River Site (SRS), South Carolina, and processed for grain-size, radionuclide dating …

Soil Hydraulic Property Estimation Under Major Land-Uses In The Shawnee Hills, Trinity Joseph Baker

Theses and Dissertations--Plant and Soil Sciences

The ability to map soil moisture is becoming more important with changing climates and modeling these effects depends on reliable estimations of hydrologic soil properties under different land managements. This study: 1) tests the application of existing soil hydraulic property estimation methods against in-situ values of six catenas under two covers (forest and grass); 2) validate Random Forest Algorithm (RF) estimates informed from the six catenas on two separate catenas; 3) identify Rapid Carbon Assessment (RaCA) sites within the Shawnee Hills Region that represent different land-uses (Crop, Conservation Reserve Program (CRP), Forest, and Pasture); 4) apply RF learning tree informed …

Evaluating Soil Physical And Chemical Properties Following Addition Of Non-Composted Spent Coffee And Tea For Athletic Fields, Shuang Zhou

Theses and Dissertations--Plant and Soil Sciences

Physical and chemical properties of non-composted spent coffee (CF) and tea (T) suggest they may have applications as soil amendments for improving poor soils. Studies were conducted to determine 1) the effect of amendments on grass growth and soil properties, 2) the effect of incorporation versus surface application of amendments on soil properties, and 3) the effect of amendment application frequency on grass growth and soil properties. In the first study, amendments were mixed with sand and planted to bermudagrass. Treatments included CF, T, and peat moss (PM) mixed with sand, and 100% sand as a control. In the second …

Adjustment And Optimization Of The Cropping Systems Under Water Constraint, Pingli An, Wei Ren, Xiliin Liu, Mengmei Song, Xuemin Li

Plant and Soil Sciences Faculty Publications

The water constraint on agricultural production receives growing concern with the increasingly sharp contradiction between demand and supply of water resources. How to mitigate and adapt to potential water constraint is one of the key issues for ensuring food security and achieving sustainable agriculture in the context of climate change. It has been suggested that adjustment and optimization of cropping systems could be an effective measure to improve water management and ensure food security. However, a knowledge gap still exists in how to quantify potential water constraint and how to select appropriate cropping systems. Here, we proposed a concept of …

Comparative Transcriptomic Analysis Of Two Brassica Napus Near-Isogenic Lines Reveals A Network Of Genes That Influences Seed Oil Accumulation, Jingxue Wang, Sanjay Kumar Singh, Chunfang Du, Chen Li, Jianchun Fan, Sitakanta Pattanaik, Ling Yuan

Plant and Soil Sciences Faculty Publications

Rapeseed (Brassica napus) is an important oil seed crop, providing more than 13% of the world’s supply of edible oils. An in-depth knowledge of the gene network involved in biosynthesis and accumulation of seed oil is critical for the improvement of B. napus. Using available genomic and transcriptomic resources, we identified 1,750 acyl-lipid metabolism (ALM) genes that are distributed over 19 chromosomes in the B. napus genome. B. rapa and B. oleracea, two diploid progenitors of B. napus, contributed almost equally to the ALM genes. Genome collinearity analysis demonstrated that the majority of the …

Vasoactivity And Vasoconstriction Changes In Cattle Related To Time Off Toxic Endophyte-Infected Tall Fescue, James L. Klotz, Glen E. Aiken, Jessica R. Bussard, Andrew P. Foote, David L. Harmon, Ben M. Goff, F. Neal Schrick, James R. Strickland

Plant and Soil Sciences Faculty Publications

Previous research has indicated that serotonergic and α-adrenergic receptors in peripheral vasculature are affected by exposure of cattle grazing toxic endophyte-infected (E+; Epichlöe coenophialia) tall fescue (Lolium arundinaceum). The objective of this experiment was to determine the period of time necessary for the vascular effects of ergot alkaloids to subside. Two experiments were conducted to investigate changes in vascular contractile response and vasoconstriction over time relative to removal from an ergot alkaloid-containing E+ tall fescue pasture. In Experiment 1, lateral saphenous vein biopsies were conducted on 21 predominantly Angus steers (357 ± 3 kg body weight) at …

Hydroclimatic Contrasts Over Asian Monsoon Areas And Linkages To Tropical Pacific Ssts, Hai Xu, Jianghu Lan, Enguo Sheng, Bin Liu, Keke Yu, Yuanda Ye, Zhengguo Shi, Peng Cheng, Xulong Wang, Xinying Zhou, Kevin M. Yeager

Earth and Environmental Sciences Faculty Publications

Knowledge of spatial and temporal hydroclimatic differences is critical in understanding climatic mechanisms. Here we show striking hydroclimatic contrasts between northern and southern parts of the eastern margin of the Tibetan Plateau (ETP), and those between East Asian summer monsoon (EASM) and Indian summer monsoon (ISM) areas during the past ~2,000 years. During the Medieval Period, and the last 100 to 200 years, the southern ETP (S-ETP) area was generally dry (on average), while the northern ETP (N-ETP) area was wet. During the Little Ice Age (LIA), hydroclimate over S-ETP areas was wet, while that over N-ETP area was dry …

Methane Emissions From Global Rice Fields: Magnitude, Spatiotemporal Patterns, And Environmental Controls, Bowen Zhang, Hanqin Tian, Wei Ren, Bo Tao, Chaoqun Lu, Jia Yang, Kamaljit Banger, Shufen Pan

Plant and Soil Sciences Faculty Publications

Given the importance of the potential positive feedback between methane (CH₄) emissions and climate change, it is critical to accurately estimate the magnitude and spatiotemporal patterns of CH₄ emissions from global rice fields and better understand the underlying determinants governing the emissions. Here we used a coupled biogeochemical model in combination with satellite-derived contemporary inundation area to quantify the magnitude and spatiotemporal variation of CH₄ emissions from global rice fields and attribute the environmental controls of CH₄ emissions during 1901–2010. Our study estimated that CH₄ emissions from global rice fields varied from 18.3 ± …

Modeling PCo2 Variability In The Gulf Of Mexico, Zuo Xue, Ruoying He, Katja Fennel, Wei-Jun Cai, Steven Lohrenz, Wei-Jen Huang, Hanqin Tian, Wei Ren, Zhengchen Zang

Plant and Soil Sciences Faculty Publications

A three-dimensional coupled physical–biogeochemical model was used to simulate and examine temporal and spatial variability of sea surface pCO₂ in the Gulf of Mexico (GoM). The model was driven by realistic atmospheric forcing, open boundary conditions from a data-assimilative global ocean circulation model, and observed freshwater and terrestrial nutrient and carbon input from major rivers. A 7-year model hindcast (2004–2010) was performed and validated against ship measurements. Model results revealed clear seasonality in surface pCO₂ and were used to estimate carbon budgets in the Gulf. Based on the average of model simulations, the GoM was a …

Regulation Of Pyrroloquinoline Quinone-Dependent Glucose Dehydrogenase Activity In The Model Rhizosphere-Dwelling Bacterium Pseudomonas Putida Kt2440, Ran An, Luke Moe

Plant and Soil Sciences Faculty Publications

Soil-dwelling microbes solubilize mineral phosphates by secreting gluconic acid, which is produced from glucose by a periplasmic glucose dehydrogenase (GDH) that requires pyrroloquinoline quinone (PQQ) as a redox coenzyme. While GDH-dependent phosphate solubilization has been observed in numerous bacteria, little is known concerning the mechanism by which this process is regulated. Here we use the model rhizosphere-dwelling bacterium Pseudomonas putida KT2440 to explore GDH activity and PQQ synthesis, as well as gene expression of the GDH-encoding gene (gcd) and PQQ biosynthesis genes (pqq operon) while under different growth conditions. We also use reverse transcription-PCR to identify transcripts …

A R2r3-Myb Transcription Factor Regulates The Flavonol Biosynthetic Pathway In A Traditional Chinese Medicinal Plant, Epimedium Sagittatum, Wenjun Huang, A. B. M. Khaldun, Jianjun Chen, Chanjuan Zhang, Haiyan Lv, Ling Yuan, Ying Wang

Plant and Soil Sciences Faculty Publications

Flavonols as plant secondary metabolites with vital roles in plant development and defense against UV light, have been demonstrated to be the main bioactive components (BCs) in the genus Epimedium plants, several species of which are used as materials for Herba Epimedii, an important traditional Chinese medicine. The flavonol biosynthetic pathway genes had been already isolated from Epimedium sagittatum, but a R2R3-MYB transcription factor regulating the flavonol synthesis has not been functionally characterized so far in Epimedium plants. In this study, we isolated and characterized the R2R3-MYB transcription factor EsMYBF1 involved in regulation of the flavonol biosynthetic pathway …

High-Input Management Systems Effect On Soybean Seed Yield, Yield Components, And Economic Break-Even Probabilities, John M. Orlowski, Bryson J. Haverkamp, Randall G. Laurenz, David A. Marburger, Eric W. Wilson, Shaun N. Casteel, Shawn P. Conley, Seth L. Naeve, Emerson D. Nafziger, Kraig L. Roozeboom, William J. Ross, Kurt D. Thelen, Chad Lee

Plant and Soil Sciences Faculty Publications

Elevated soybean [Glycine max (L.) Merr.] prices have spurred interest in maximizing soybean seed yield and has led growers to increase the number of inputs in their production systems. However, little information exists about the effects of high-input management on soybean yield and profitability. The purpose of this study was to investigate the effects of individual inputs, as well as combinations of inputs marketed to protect or increase soybean seed yield, yield components, and economic break-even probabilities. Studies were established in nine states and three soybean growing regions (North, Central, and South) between 2012 and 2014. In each site-year …

Performance Of Endophyte Infected Tall Fescue In Europe And North America, Kari Saikkonen, Timothy D. Phillips, Stanley H. Faeth, Rebecca L. Mcculley, Irma Saloniemi, Marjo Helander

Plant and Soil Sciences Faculty Publications

Human assisted plant invasions from Europe to North America have been more common than the reverse. We tested endophyte-mediated performance of tall fescue in parallel three year experiments in Europe and the USA using endophyte infected and uninfected wild and cultivated plants. Experimental plants were subjected to nutrient and water treatments. Whereas endophyte infection increased tall fescue performance in general, the effects of endophytes on plant growth and reproduction varied among plant origins under different environmental conditions. Naturally endophyte-free Finnish cultivar ‘Retu’ performed equally well as ‘Kentucky-31’ in both geographic locations. All Eurasian origin plants performed well in the US. …

Photocatalytic Reduction Of Fumarate To Succinate On Zns Mineral Surfaces, Ruixin Zhou, Marcelo I. Guzman

Chemistry Faculty Publications

The reductive tricarboxylic acid (rTCA) cycle is an important central biosynthetic pathway that fixes CO₂ into carboxylic acids. Among the five reductive steps in the rTCA cycle, the two-electron reduction of fumarate to succinate proceeds nonenzymatically on the surface of photoexcited sphalerite (ZnS) colloids suspended in water. This model reaction is chosen to systematically study the surface photoprocess occurring on ZnS in the presence of [Na₂S] (1–10 mM) hole scavenger at 15 °C. Experiments at variable pH (5–10) indicate that monodissociated fumaric acid is the primary electron acceptor forming the monoprotic form of succinic acid. The following …

Nanoparticles Composed Of Zn And Zno Inhibit Peronospora Tabacina Spore Germination In Vitro And P. Tabacina Infectivity On Tobacco Leaves, George Wagner, Victor Korenkov, Jonathan D. Judy, Paul M. Bertsch

Plant and Soil Sciences Faculty Publications

Manufactured nanoparticles (NPs) are increasingly being used for commercial purposes and certain NP types have been shown to have broad spectrum antibacterial activity. In contrast, their activities against fungi and fungi-like oomycetes are less studied. Here, we examined the potential of two types of commercially available Zn NPs (Zn NPs and ZnO NPs) to inhibit spore germination and infectivity on tobacco leaves resulting from exposure to the fungi-like oomycete pathogen Peronospora tabacina (P. tabacina). Both types of NPs, as well as ZnCl₂ and bulk ZnO control treatments, inhibited spore germination compared to a blank control. ZnO ENMs …

Identifying Rare Fhb-Resistant Segregants In Intransigent Backcross And F2 Winter Wheat Populations, Anthony J. Clark, Daniela Sarti-Dvorjak, Gina Brown-Guedira, Yanhong Dong, Byung-Kee Baik, David A. Van Sanford

Plant and Soil Sciences Faculty Publications

Fusarium head blight (FHB), caused mainly by Fusarium graminearum Schwabe [telomorph: Gibberella zeae Schwein.(Petch)] in the US, is one of the most destructive diseases of wheat (Triticum aestivum L. and T. durum L.). Infected grain is usually contaminated with deoxynivalenol (DON), a serious mycotoxin. The challenge in FHB resistance breeding is combining resistance with superior agronomic and quality characteristics. Exotic QTL are widely used to improve FHB resistance. Success depends on the genetic background into which the QTL are introgressed, whether through backcrossing or forward crossing; QTL expression is impossible to predict. In this study four high-yielding soft red …

Mapping Irrigated And Rainfed Wheat Areas Using Multi-Temporal Satellite Data, Ning Jin, Bo Tao, Wei Ren, Meichen Feng, Rui Sun, Liang He, Wei Zhuang, Qiang Yu

Plant and Soil Sciences Faculty Publications

Irrigation is crucial to agriculture in arid and semi-arid areas and significantly contributes to crop development, food diversity and the sustainability of agro-ecosystems. For a specific crop, the separation of its irrigated and rainfed areas is difficult, because their phenology is similar and therefore less distinguishable, especially when there are phenology shifts due to various factors, such as elevation and latitude. In this study, we present a simple, but robust method to map irrigated and rainfed wheat areas in a semi-arid region of China. We used the Normalized Difference Vegetation Index (NDVI) at a 30 × 30 m spatial resolution …

Characterizing Genotype X Management Interactions On Soybean Seed Yield, David A. Marburger, Bryson J. Haverkamp, Randall G. Laurenz, John M. Orlowski, Eric W. Wilson, Shaun N. Casteel, Chad D. Lee, Seth L. Naeve, Emerson D. Nafziger, Kraig L. Roozeboom, William J. Ross, Kurt D. Thelen, Shawn P. Conley

Plant and Soil Sciences Faculty Publications

Increased soybean [Glycine max (L.) Merr.] commodity prices in recent years have generated interest in high-input systems to increase yield. The objective of this study was to evaluate the effects of current, high-yielding cultivars under high- and low-input systems on soybean yield and yield components. Research trials were conducted at 19 locations spanning nine states from 2012 to 2014. At each location, six high-yielding cultivars were grown under three input systems: (i) standard practice (SP, current recommended practices), (ii) high-input treatment consisting of a seed treatment fungicide, insecticide, nematistat, inoculant, and lipo-chitooligosaccharide (LCO); soil-applied N fertilizer; foliar LCO, fertilizer, …

Photo Highlights Of The 14th Heart Of America Grazing Conference, Heart Of America Grazing Conference

Kentucky Grazing Conference

No abstract provided.

Picking Apples Off The Grazing Tree: How Far Can We Extend The Grazing Season Profitably?, Greg S. Halich

Kentucky Grazing Conference

Will grazing more and feeding less hay always increase profitability? There are many cases where cattle farmers could graze more days profitably. I would guess that more than half the cattlemen in Kentucky and the region could find ways to do so. But the statement is not universally correct and we need to evaluate the specific situation to determine if increasing grazing days will pay off.

Grazing Corn To Maximize Late Summer And Fall Gains, Jeff Lehmkuhler, Eric Vanzant

Kentucky Grazing Conference

Corn is a warm-season grass with a growth pattern dependent on temperatures. Warmer temperatures accelerate growth while cooler temperatures slow maturation. Thermal time is often referred to as Growing Degree Days (GGD) and calculated as GGD = ((Max Temp – Min Temp)/2) – 50 when calculating in Fahrenheit (Nielsen, 2012). In the upper transition zone, corn thrives and is the major planted crop. The warmer temperatures of the summer months combined with adequate precipitation allows this crop to be a potentially high yielding crop.

Native Warm-Season Grasses: Naturally Adapted Productive Pastures, Pat Keyser

Kentucky Grazing Conference

The series of severe droughts between 2007 and 2012 resulted in substantial decreases in cattle numbers – and enterprises – in our region. Some of the impact of these droughts may have been offset if producers in the region had reliable, drought-resilient summer forages. For all of the benefits of tall fescue, it was never meant to provide our summer forage. After all, it is a cool-season grass. What we have been learning about toxicosis in recent years further emphasizes the value of having alternative forages available during summer months.

How Diversity Extends The Grazing Season At Dogwood Farm, Debby Dulworth

Kentucky Grazing Conference

This article was previously published in Cow Country News.

Cattle are a valuable resource these days, in ways that most people, consumers and producers alike, haven’t yet realized. Putting some other resources into making the change for a better grazing system makes sense, especially here in Kentucky, where grass has, in the past, been the basis of a healthy and expansive economy. Grass can once again be the basis for a healthy economy, if enough people with the vision to see its possibilities get involved and make it happen. A truly healthy economy begins with good human health and …

Putting Some Pop Back In Your Crop: Alfalfa In Crop Rotations, Ben M. Goff

Kentucky Grazing Conference

While alfalfa is often recognized as the “Queen of the Forages”, corn may be considered “King of the Crops” and currently ranks as the nation’s largest acreage crop with over 87 million acres. The corn acreage U.S. has continued to increase in recent years for various reasons including greater market demand, a shift towards larger farms that focus on a fewer number of crops, and the development of improved varieties and management practices. According to the U.S. Census of Agriculture, the acreage devoted to corn and soybeans has risen by 64 and 255%, respectively, over the last 30 years, while …

Reduced Or Low Lignin Alfalfa: Advantages For Hay And Grazing, S. Ray Smith

Kentucky Grazing Conference

Lignin is an essential structural component of all land plants. It fills spaces in the cell wall between cellulose, hemicellulose, and pectin. Lignin provides the strength to plants from giant Sequoia trees to alfalfa growing in hay fields. A good analogy is that lignin is like the steel reinforcing rods in concrete. Life on earth would not be possible without lignin to allow plants to grow upright. The limitation for livestock is that lignin is indigestible. Forage breeders have long realized that the quickest way to improve forage quality would be to reduce lignin concentration, but if lignin is reduced …

Grazing Alfalfa: Producer Perspective, Bob Hall

Kentucky Grazing Conference

Scott County native Robert (Bob) Hall, Jr. is a man of many hats. He and his wife Bonnie have embarked on many ventures on their farm including sheep, hogs and tobacco. Hall was born and raised on the farm outside of Georgetown, where he currently resides and operates a stocker operation. Some may recognize Hall for the feed mill he purchased in the 1960’s known as Hallway Feeds. Early in the Mill’s history over 90 percent of their sales were to dairy producers. Now 95 percent of company’s sales go to the equine industry. Hallway Feed is sold and distributed …