Life Sciences Commons^™

Competition And Herbivory Influence The Survival, Growth, And Physiology Of Native Tree Seedlings In The Kentucky Inner Bluegrass Savanna-Woodland, James D. Shaffer

Theses and Dissertations--Biology

Terrestrial plant communities are shaped by competition for resources, herbivory, and abiotic processes. Savanna systems represent a dynamic coexistence of contrasting life forms (grasses and trees) shaped by competition and disturbance. The Kentucky Inner Bluegrass Savanna-Woodland (KIBSW) is described as an open woodland of shade intolerant species; however, climatic, and edaphic conditions can support closed-canopy forest. After European pioneer settlement (c1750-1800), over 99% of “savanna-woodlands” have been lost. KIBSW remnants are experiencing a recruitment failure, leading to a dominance shift in tree communities. I researched how tree-grass competition and mammalian herbivory influence KIBSW regeneration and maintenance. The KIBSW does not …

Bat Activity On West Virginia Mined Lands Restored Via The Forestry Reclamation Approach, Briana C. Snyder

Theses and Dissertations--Forestry and Natural Resources

The Forestry Reclamation Approach (FRA) is a practical guide to reforesting surface mined lands. Bats, as a unique group of species with declining populations, could benefit from this reforestation. In order to determine if the FRA is providing suitable bat foraging habitat, I surveyed bat activity at created depressional wetlands on 1-year old and 8-year old FRA restored lands (FRA1; FRA8), as well as at naturally formed wetlands in regenerating forest on traditionally reclaimed mined land (~40 years old; REGEN) and wetlands in mature forest not previously mined (MAT). I passively recorded echolocation calls for 12 nights across sixteen sites …

Gene Silencing Provides Insights Into Bark Beetle Biology And Creates Potential For Broad Scale Forest Protection, Beth R. Kyre

Theses and Dissertations--Entomology

Dendroctonus bark beetles are among the most economically and ecologically significant forest pests in North America and play a critical role in the overall health of conifer forest ecosystems. Dendroctonus bark beetles influence ecosystem benefits and biodiversity and drive forest succession, and adversely affect timber production, forest management, and recreation. As temperatures surge and climatic fluctuations become more extreme, catastrophic bark beetle outbreaks are increasing in frequency, escalating pressures on highly vulnerable conifer forests already compromised by heat and drought. Eruptive outbreaks of Dendroctonus beetles are largely unhindered by traditional silvicultural management; these practices further disrupt forest ecosystem services, including …

Exploration Of Lignin-Based Superabsorbent Polymers (Hydrogels) For Soil Water Management And As A Carrier For Delivering Rhizobium Spp., Toby Adjuik

Theses and Dissertations--Biosystems and Agricultural Engineering

Superabsorbent polymers (hydrogels) as soil amendments may improve soil hydraulic properties and act as carrier materials beneficial to soil microorganisms. Researchers have mostly explored synthetic hydrogels which may not be environmentally sustainable. This dissertation focused on the development and application of lignin-based hydrogels as sustainable soil amendments. This dissertation also explores the development of pedotransfer transfer functions (PTFs) for predicting saturated hydraulic conductivity using statistical and machine learning methods with a publicly available large data set. A lignin-based hydrogel was synthesized, and its impact on soil water retention was determined in silt loam and loamy fine sand soils. Hydrogel treatment …

Residual Spatial Autocorrelation In Macroecological And Biogeographical Modeling: A Review, Guetchine Gaspard

Theses and Dissertations--Geography

Macroecological and biogeographical modelers have predicted the distribution of species across space relying on the relationship between biotic processes and environmental variables. Such a method employs data associated, for instance, with species abundance or presence/absence, climate, geomorphology, and soils. Statistical analyses found in previous studies have highlighted the importance of accounting for the effects of spatial autocorrelation (SAC), which indicates a level of dependence between pairs of nearby observations. A consensus has existed that residual spatial autocorrelation (rSAC) can substantially impact modeling processes and inferences. However, more emphasis should be put on identifying the sources of rSAC and the degree …

Evaluating The Biotic Condition Of Restored Streams In Kentucky’S Inner Bluegrass Region, Charles Cole Crankshaw

Theses and Dissertations--Biosystems and Agricultural Engineering

Numerous stream restoration projects have been implemented in Kentucky’s Inner Bluegrass region to offset anthropogenic impacts. These projects range from full channel realignments to volunteer-led riparian installations. To assess the ability of said projects to restore stream habitat and biota, full restoration (n=12) and riparian (n=6) sites were compared to reference (n=6) and disturbed (n=12) sites using RBP and SVAP protocols, macroinvertebrate samples, and geomorphology. General trends for SVAP, RBP, and BI scores, starting with highest habitat or biotic quality, were reference sites, full and riparian restoration sites, then disturbed sites. The number of EPT taxa, another indicator of biological …

Soil Carbon Dynamics And Greenhouse Gas Emissions In Conservation Tillage Systems At Multiple Scales, Yawen Huang

Theses and Dissertations--Plant and Soil Sciences

Conservation tillage practices like no-tillage and reduced tillage have been widely implemented worldwide, with expectations they would provide multiple benefits (e.g., yield enhancement and soil carbon sequestration) for food security and climate adaptation and mitigation. However, the adoption of conservation tillage faces both opportunities and challenges. A knowledge gap still exists regarding the effects of conservation tillage on the carbon cycle in agroecosystems. This dissertation reflects a comprehensive evaluation of conservation tillage at multiple scales using an integrated systems approach, a combination of data synthesis, the agriculture ecosystem model, and field observations and measurements. I first conducted a meta-analysis to …

Conservation Limnogeology And Benthic Habitat Mapping In Central Lake Tanganyika (Tanzania), Joseph S. Lucas

Theses and Dissertations--Earth and Environmental Sciences

Small scale protected zones are valuable for helping the health and productivity of fisheries at Lake Tanganyika (East Africa). Spatial placement of protected areas relies on accurate maps of benthic habitats, consisting of detailed bathymetry data and information on lake-floor substrates. This information is unknown for most of Lake Tanganyika. Fish diversity is known to correlate with rocky substrates in ≤ 30 m water depth, which provide spawning grounds for littoral and pelagic species. These benthic habitats form important targets for protected areas, if they can be precisely located.

At the NMVA, echosounding defined the position of the 30-m isobath …

Pressure-Driven Stabilization Of Capacitive Deionization, Landon S. Caudill

Theses and Dissertations--Mechanical Engineering

The effects of system pressure on the performance stability of flow-through capacitive deionization (CDI) cells was investigated. Initial data showed that the highly porous carbon electrodes possessed air/oxygen in the micropores, and the increased system pressure boosts the gases solubility in saline solution and carries them out of the cell in the effluent. Upon applying a potential difference to the electrodes, capacitive-based ion adsorption occurs in competition with faradaic reactions that consume oxygen. Through the addition of backpressure, the rate of degradation decreases, allowing the cell to maintain its salt adsorption capacity (SAC) longer. The removal of oxygen from the …

Efficacy Of Herbivore Exclusion On Planted Tree Seedling Vitality On A Reclaimed Surface Mine In Eastern Kentucky, Zachary J. Hackworth

Theses and Dissertations--Forestry and Natural Resources

Conventional Appalachian surface-mine reclamation techniques repress natural forest regeneration, and tree plantings are often necessary for reforestation. Reclaimed Appalachian surface mines harbor a suite of mammal herbivores that forage on recently planted seedlings. Anecdotal reports across Appalachia have implicated herbivory in the hindrance and failure of reforestation efforts, yet empirical evaluation of herbivory impacts on planted seedling vitality in this region remains relatively uninitiated. First growing-season survival, height growth, and mammal herbivory damage of black locust (Robinia pseudoacacia L.), shortleaf pine (Pinus echinata Mill.), and white oak (Quercus alba L.) are presented in response to varying intensities …

Can Increasing Grass-Fungal Endophyte Symbiotic Diversity Enhance Grassland Ecosystem Functioning?, Mahtaab Bagherzadeh

Theses and Dissertations--Plant and Soil Sciences

The relationship between biodiversity and ecosystem functioning is important in maintaining agroecosystem sustainability. Plant-microbe symbioses, such as exists between the grass tall fescue (Schedonorus arundinaceum) and the asexual fungal endophyte Epichloë coenophiala, can be utilized to enhance agroecosystem functions, such as herbivore resistance. “Novel” E. coenophiala strains that vary in the production of mammal- and insect-toxic compounds have been identified, inserted into tall fescue cultivars, and are planted in pastures globally. Novel fungal endophyte-tall fescue associations may have divergent ecosystem function effects. This study assessed effects of different fescue-endophyte symbiotic combinations on pasture ecosystem function, including aboveground …

Effects Of Mountaintop Removal Mining On Population Dynamics Of Stream Salamanders, Sara B. Freytag

Theses and Dissertations--Forestry and Natural Resources

Mountaintop removal mining (MTR) is a notorious stressor of stream ecosystems in the Central Appalachians. Valley fills (VF) lead to reduced occupancy, abundance, and species richness of stream salamanders. Multiple factors may be responsible for these reductions, but specifically habitat fragmentation and degradation may reduce colonization rates and increase local extinction rates. From 2013-2015, repeated counts of salamanders were conducted in stream reaches impacted by MTR/VF and compared to counts in reference reaches to answer the question: do stream salamander population dynamics differ between stream reaches impacted by MTR/VF and reference stream reaches? I also investigated dynamics of stream habitat …

Effects Of Epichloë Coenophiala−Tall Fescue Symbiosis On Plant-Microbe-Soil Interactions In A Temperate Pasture, Lindsey C. Slaughter

Theses and Dissertations--Plant and Soil Sciences

Plants interact in myriad ways with microorganisms to influence ecosystem processes such as nutrient cycling, which can regulate ecosystem response to global change. One important plant-microbe symbiosis occurs between cool-season grasses and asexual fungal Epichloë endophytes, such as tall fescue (Schedonorus arundinaceus) and Epichloë coenophiala. Because the common toxic strain of the endophyte (CTE) harms grazing livestock, non-livestock toxic endophyte (NTE) strains have been developed and are increasingly deployed in pastures. Little is known about how these symbioses impact other plant-microbe interactions and microbe-mediated soil processes in grassland ecosystems. I conducted three studies to determine how E. …

Ecology Of Two Reintroduced Black Bear Populations In The Central Appalachians, Sean Mccarthy Murphy

Theses and Dissertations--Animal and Food Sciences

Reintroduced populations are vulnerable to demographic and environmental stochasticity, deleterious genetic effects, and reduced population fitness, all of which can increase extinction probability. Population viability is principle to determining the status of reintroduced populations and for guiding management decisions. To attempt to reestablish black bear (Ursus americanus) populations in the central Appalachians, two reintroductions using small founder groups occurred during the 1990s in the Big South Fork area along the Kentucky-Tennessee border (BSF) and in the Jefferson National Forest along the Kentucky-Virginia border (KVP). My objectives were to estimate demographic and genetic parameters, and to evaluate long-term viability …

Soil And Biosolid Nano- And Macro-Colloid Properties And Contaminant Transport Behavior, Jessique L. Ghezzi

Theses and Dissertations--Plant and Soil Sciences

Despite indications that they are potential contaminant transport systems and threats to groundwater quality, very little effort has been invested in comparing contaminant transport behavior of natural environmental nanocolloids and their corresponding macrocolloid fractions in the presence of As, Se, Pb, and Cu contaminants. This study involved physico-chemical, mineralogical, stability and contaminant-transport characterizations of nano- (< 100 nm) and macro-colloids (100-2000 nm) fractionated from three Kentucky soils and one biosolid waste. Particle size was investigated with SEM/TEM and dynamic light scattering. Surface reactivity was estimated using CEC and zeta potential. Mineralogical composition was determined by XRD, FTIR, and thermogravimetric analyses. Sorption isotherms assessed affinities for Cu²⁺, Pb²⁺, AsO₃^-, and SeO₄^-2 contaminants, while settling kinetics experiments of suspensions at 0, 2 and 10 mg/L contaminants determined stability and transportability potential. Undisturbed 18x30 cm KY Ashton Loam soil monoliths were also used for …

Monitoring The Influence Of Acid Deposition On Soil And Implications To Forest Health In The Daniel Boone National Forest, Tyler M. Sanderson

Theses and Dissertations--Forestry and Natural Resources

Combustion of fossil fuels has contributed to many environmental problems including acid deposition. The Clean Air Act (CAA) was created to reduce ecological problems by cutting emissions of sulfur and nitrogen. Reduced emissions and rainfall concentrations of acidic ions have been observed since the enactment of the CAA, but soils continue to receive some acid inputs. Soils sensitive to acid deposition have been found to have low pH, a loss of base cations and a shift in the mineral phase controlling the activity of Al³⁺ and/or SO₄^2-. If inputs continue, soil may be depleted of base …

Addressing Public Health Risks Of Persistent Pollutants Through Nutritional Modulation And Biomimetic Nanocomposite Remediation Platforms, Bradley J. Newsome

Theses and Dissertations--Chemistry

Due to their relative chemical stability and ubiquity in the environment, chlorinated organic contaminants such as polychlorinated biphenyls (PCBs) pose significant health risks and enduring remediation challenges. Engineered nanoparticles (NPs) provide a novel platform for sensing/remediation of these toxicants, in addition to the growing use of NPs in many industrial and biomedical applications, but there remains concern for their potential long-term health effects. Research highlighted herein also represents a transdisciplinary approach to address human health challenges associated with exposure to PCBs and NPs. The objectives of this dissertation research are two-fold, 1) to develop effective methods for capture/sensing and remediation …

Natural Phenomena As Potential Influence On Social And Political Behavior: The Earth’S Magnetic Field, Jackie R. East

Theses and Dissertations--Political Science

Researchers use natural phenomena in a number of disciplines to help explain human behavioral outcomes. Research regarding the potential effects of magnetic fields on animal and human behavior indicates that fields could influence outcomes of interest to social scientists. Tests so far have been limited in scope. This work is a preliminary evaluation of whether the earth’s magnetic field influences human behavior it examines the baseline relationship exhibited between geomagnetic readings and a host of social and political outcomes. The emphasis on breadth of topical coverage in these statistical trials, rather than on depth of development for any one model, …

Forest Harvest Equipment Movement And Sediment Delivery To Streams, Daniel Whiteside Bowker

Theses and Dissertations--Forestry and Natural Resources

Streamside management zones (SMZs) have become important management techniques to prevent the introduction of sediment to stream networks. This study examined the current Kentucky best management practice (BMP) guidelines for SMZs by outfitting mobile forest harvest equipment with global positioning system (GPS) receivers, enabling modeling of equipment traffic and spatial analysis of stream sediment delivery. Three SMZ configurations were implemented during commercial timber harvest, along with four different techniques of crossing ephemeral channels, in order to determine where and why sediment was introduced to the stream network. Results indicate that increasing the SMZ buffer width leads to decreased sediment delivery, …

Managing Soil Microbial Communities With Organic Amendments To Promote Soil Aggregate Formation And Plant Health, Shawn T. Lucas

Theses and Dissertations--Plant and Soil Sciences

The effects of managing soil with organic amendments were examined with respect to soil microbial community dynamics, macroaggregate formation, and plant physio-genetic responses. The objective was to examine the possibility of managing soil microbial communities via soil management, such that the microbial community would provide agronomic benefits. In part one of this research, effects of three amendments (hairy vetch residue, manure, compost) on soil chemical and microbial properties were examined relative to formation of large macroaggregates in three different soils. Vetch and manure promoted fungal proliferation (measured via two biomarkers: fatty acid methyl ester 18:2ω6c and ergosterol) and also stimulated …

Factors Influencing The Establishment And Survival Of Native Hardwood Tree Seedlings Of The Kentucky Inner Bluegrass Blue Ash-Oak Savanna-Woodland, James D. Shaffer

Theses and Dissertations--Biology

Historically, the Kentucky Inner Bluegrass blue ash-oak savanna-woodland was the primary ecosystem of the Inner Bluegrass Region (IBR) of Kentucky. After European settlement, the majority (>99%) of Bluegrass savanna was converted to agricultural and urban land uses. Currently remnant savanna tree species are failing to recruit. Therefore, a long-term restoration ecology project researching competition and disturbance on seedling establishment, survival, and growth has been established at Griffith Woods (the largest remaining savanna in Kentucky) in Harrison Co., KY. Fourteen native hardwood tree species (a total of 6,168 seedlings) have been experimentally planted. Light, soil, surrounding vegetation, and herbivory, factors …

Evaluating The Sustainability Of Four Organic Vegetable Production Systems, Delia W. Scott

Theses and Dissertations--Plant and Soil Sciences

A field study evaluating the sustainability of four organic vegetable production systems was conducted in Lexington, Kentucky in 2006 and 2007. The four systems included no-till, raised beds covered with biodegradable black mulch, bare ground with shallow cultivation, and bare ground with shallow cultivation and wood chip mulch. The two-year study compared yield, weed control, labor, and costs associated with each system, as well as physical, chemical, and microbiological soil characteristics. In 2006, tomatoes (Lycopersicon esculentum Mill.) were grown in the four systems, with no significant difference in yield. Summer squash (Cucurbita pepo L.) was grown in the …

Characteristics Of Kentucky Agricultural Operations Participating In Nrcs Conservation Programs, Carmen T. Agouridis

MPA/MPP/MPFM Capstone Projects

The Natural Resource Conservation Service (NRCS) designs and promotes a wide variety of conservation practices and programs that enhance the environment by reducing soil erosion, improving water quality, and enhancing and creating wildlife habitat. The impact of these practices and programs is largely dependent on the voluntary participation of landowners. Thus, central to the success of the NRCS conservation programs is an understanding of the characteristics of landowners and operations participating in these programs.

Using operator and operation characteristics from the 1997, 2002, and 2007 Censuses of Agriculture and controlling for county fixed effects, this study 1) identifies significant characteristics …

Water Quality Trading Markets For The Kentucky River Basin: A Point Source Profile, Ronald Childress Jr.

Theses and Dissertations--Agricultural Economics

This study assessed the feasibility and suitability of a Water Quality Trading (WQT) program within the Kentucky River Basin (KRB). The study’s focal point was based on five success factors of a WQT program: environmental suitability, geospatial orientation, participant availability, regulatory incentive, and economic incentive. The study utilized these five success factors, geographical characteristics, and Discharge Monitoring Reports (DMR) to assess the feasibility of a WQT program.

The assessment divided the KRB into five eight digit Hydrologic Unit Codes (HUC), North, Middle, and South Fork, Middle Basin, and Lower Basin, to determine regional impacts caused by the nutrient PSs. Individual …

Method Development For Detecting And Characterizing Manufactured Silver Nanoparticles In Soil Pore Water Using Asymmetrical Flow Field-Flow Fractionation, Annie R. Whitley

Theses and Dissertations--Plant and Soil Sciences

Recent advances in nanotechnology have led to the production of materials with nanoscale dimensions (nm) and properties distinctly different from their bulk (>100 nm) counterparts. With increased use, it is inevitable that nanomaterials will accumulate in the environment and there is concern that the novel properties of nanomaterials could result in detrimental environmental and human health effects. In particular, there has been concern recently regarding the use of silver (Ag) based nanomaterials as antimicrobial agents in consumer and medical products. Current regulations dealing with the discharge of metals into the environment are based on total concentrations with no consideration …

The Ecology Of Disturbances And Global Change In The Montane Grasslands Of The Nilgiris, South India, Madhusudan P. Srinivasan

University of Kentucky Doctoral Dissertations

Biodiversity rich regions worldwide face threats from various global change agents. This research quantifies environmental influences on vegetation, and the impacts of exotic woody plant invasion and anthropogenic nitrogen (N) deposition in a global biodiversity hotspot. The study was conducted in the montane grasslands of the Nilgiris, Western Ghats, and outlines potential management options for this region. Specifically, I examined (1) the role of environmental factors in influencing native plant distribution and ecosystem properties, (2) the status and impact of exotic shrub (Scotch broom, henceforth broom) invasion, (3) the role of disturbances in the success of broom, (4) the role …

Streamflow Prediction Using Gis For The Kentucky River Basin, Bakkiyalakshmi Palanisamy

University of Kentucky Doctoral Dissertations

The study was aimed at developing a simple methodology for flow prediction in ungauged basins using existing data resources. For this purpose, the streamflow measurements across the Kentucky River Basin located in Kentucky, USA were obtained from United States Geological Survey (USGS) archive. The flow transferring characteristics of the subbasins of the Kentucky River Basin were obtained by combining downstream and upstream stream gauges. The flow transferring function thus derived were related to watershed, channel and flow characteristics of the subbasins by multiple regression analysis. The gauge pairs were divided into two classes of subbasins representing Upper and Lower Kentucky, …