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Full-Text Articles in Earth Sciences

An Integrated Pest Management Ipm Approach In Alfalfa Production Systems, Lee H. Townsend Feb 2018

An Integrated Pest Management Ipm Approach In Alfalfa Production Systems, Lee H. Townsend

Kentucky Alfalfa and Stored Forage Conference

Alfalfa lends itself to an integrated pest management (IPM) approach for alfalfa weevils and potato leafhoppers, the two key insect pests of the crop. Both species live in most alfalfa fields every summer. However, alfalfa can tolerate low levels of their feeding without costly yield or quality loss.


An Integrated Approach To Weed Control In Alfalfa Production Systems, Jonathan D. Green Feb 2018

An Integrated Approach To Weed Control In Alfalfa Production Systems, Jonathan D. Green

Kentucky Alfalfa and Stored Forage Conference

The importance of weed control in forage production should not be overlooked, especially when you consider the high investment associated with alfalfa and other legume forages. Weeds reduce forage yield by competing for water, sunlight, and nutrients. For example, yield obtained from the first cutting of alfalfa can be significantly reduced by a heavy infestation of common chickweed. In addition to yield losses, weeds can also lower forage quality, increase the incidence of disease and insect problems, cause premature stand loss, and create harvesting problems. Some weeds are unpalatable to livestock or, in some cases, may be poisonous.


Fertilizing High Producing Alfalfa Stands, Edwin L. Ritchey Feb 2018

Fertilizing High Producing Alfalfa Stands, Edwin L. Ritchey

Kentucky Alfalfa and Stored Forage Conference

There are no secrets for successfully producing a high quality alfalfa crop. Successful alfalfa production is a product of suitable site selection, proper fertility and pH management, good pest control, and favorable weather conditions throughout the season. This paper focuses on proper fertility and pH management practices.


Alfalfa Establishment: Getting Off To A Good Start!, Christopher D. Teutsch Feb 2018

Alfalfa Establishment: Getting Off To A Good Start!, Christopher D. Teutsch

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is a highly productive forage legume that is well adapted to transition zone states like Kentucky. It can be grazed, hayed, or ensiled. Once established and under good management, expected yields range from 5-7 tons per acre per year. High yields can only be obtained from a dense and vigorous alfalfa stand. The first step in obtaining such stands is establishment. The establishment phase of alfalfa production is critical since realization of returns from all other input costs is dependent upon having a good stand and it is expensive. It is important to remember that alfalfa establishment begins long …


Fine Tuning Varietal Selection For The Mid-South, S. Ray Smith Feb 2018

Fine Tuning Varietal Selection For The Mid-South, S. Ray Smith

Kentucky Alfalfa and Stored Forage Conference

There are many new alfalfa varieties that have come on the market each year. In fact, it can be hard keeping up with all the developments. In the following pages I will overview most of the important traits that can be found in new varieties. These include Low Lignin, Roundup Ready®, potato leafhopper resistance, higher quality, resistance to new diseases, and more… Many times I am asked “Are new varieties really worth the cost?” The best way to answer that question is to consider work by Dr. Jimmy Henning where he summarized 24 location years of Kentucky alfalfa yield data …


Foreword Of Kentucky Alfalfa And Stored Forages Conference [2018], Christopher D. Teutsch, Christi L. Forsythe Feb 2018

Foreword Of Kentucky Alfalfa And Stored Forages Conference [2018], Christopher D. Teutsch, Christi L. Forsythe

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.


Individual And Combined Effects Of Herbicide Tribenuron-Methyl And Fungicide Tebuconazole On Soil Earthworm Eisenia Fetida, Jiqiang Chen, Muhammad Saleem, Caixia Wang, Wenxing Liang, Qingming Zhang Feb 2018

Individual And Combined Effects Of Herbicide Tribenuron-Methyl And Fungicide Tebuconazole On Soil Earthworm Eisenia Fetida, Jiqiang Chen, Muhammad Saleem, Caixia Wang, Wenxing Liang, Qingming Zhang

Plant and Soil Sciences Faculty Publications

Earthworms are soil engineers that alter the soil bio-physical properties to favor plant growth whereas pesticides represent a significant threat to their abundance and soil health. Thus, we investigated the toxic effects of tribenuron-methyl (TBM) and tebuconazole (TEB) on the soil earthworm, Eisenia fetida. The TBM demonstrated low toxicity to E. fetida in the contact filter paper and artificial soil tests, with median lethal concentrations (LC50) of 135.6 μg cm−2 at 48 h and 511 mg kg−1 on day 14, respectively. Similarly, TEB also showed low toxicity to E. fetida in the artificial …


Cover Crops And Fertilization Alter Nitrogen Loss In Organic And Conventional Conservation Agriculture Systems, Rebecca E. Shelton, Krista L. Jacobsen, Rebecca L. Mcculley Jan 2018

Cover Crops And Fertilization Alter Nitrogen Loss In Organic And Conventional Conservation Agriculture Systems, Rebecca E. Shelton, Krista L. Jacobsen, Rebecca L. Mcculley

Horticulture Faculty Publications

Agroecosystem nitrogen (N) loss produces greenhouse gases, induces eutrophication, and is costly for farmers; therefore, conservation agricultural management practices aimed at reducing N loss are increasingly adopted. However, the ecosystem consequences of these practices have not been well-studied. We quantified N loss via leaching, NH3 volatilization, N2O emissions, and N retention in plant and soil pools of corn conservation agroecosystems in Kentucky, USA. Three systems were evaluated: (1) an unfertilized, organic system with cover crops hairy vetch (Vicia villosa), winter wheat (Triticum aestivum), or a mix of the two (bi-culture); (2) an organic …


Editorial To “Heat Flow: Recent Advances”, Vladimir Cermak, Shaopeng Huang, Dhananjay Ravat, Massimo Verdoya Jan 2018

Editorial To “Heat Flow: Recent Advances”, Vladimir Cermak, Shaopeng Huang, Dhananjay Ravat, Massimo Verdoya

Earth and Environmental Sciences Faculty Publications

No abstract provided.


Conservation Limnogeology And Benthic Habitat Mapping In Central Lake Tanganyika (Tanzania), Joseph S. Lucas Jan 2018

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 …


Assessing Intra-Event Phosphorus Dynamics In Drainage Water Using Phosphate Stable Oxygen Isotopes, William Ford Iii, Mark R. Williams, Megan B. Young, Kevin W. King, Eric Fischer Jan 2018

Assessing Intra-Event Phosphorus Dynamics In Drainage Water Using Phosphate Stable Oxygen Isotopes, William Ford Iii, Mark R. Williams, Megan B. Young, Kevin W. King, Eric Fischer

Biosystems and Agricultural Engineering Faculty Publications

Quantifying fluxes and pathways of dissolved reactive phosphorus (DRP) in tile-drained landscapes has been hampered by a lack of measurements that are sensitive to P fate and transport processes. One potential tool to help understand these dynamics is the oxygen isotope signature of phosphate (δ18OPO4); however, its potential benefits and limitations are not well understood for intra-event dynamics at the field scale. The objectives of this study were to quantify intra-event variability of δ18OPO4 signatures in tile drainage water and assess the efficacy of δ18OPO4 to elucidate mechanisms and flow …


Kentucky Soil Atlas, Anastasios D. Karathanasis, Usda Natural Resources And Conservation Service Jan 2018

Kentucky Soil Atlas, Anastasios D. Karathanasis, Usda Natural Resources And Conservation Service

Plant and Soil Sciences Faculty Book Gallery

From preface:

Kentucky has a diverse array of geologic, topographic, physiographic, ecological, and aquatic features that have contributed to the development and present characteristics and productivity of the soils in the state. This Soil Atlas has been prepared as an aid to further the knowledge of soils in our state and provide a basic exposure of Kentucky’s soil resources to educators, students, natural resource planners, policy makers, citizens and visitors. The objective of the publication is to present the prominent characteristics of representative soils and how they may affect soil use and management. The Atlas is meant to give a …


Surficial Geologic Map Of The Newport 7.5-Minute Quadrangle, Kentucky, Matthew Massey, Antonia E. Bottoms, Maxwell L. Hammond Iii Jan 2018

Surficial Geologic Map Of The Newport 7.5-Minute Quadrangle, Kentucky, Matthew Massey, Antonia E. Bottoms, Maxwell L. Hammond Iii

Contract Reports--KGS

The Newport 7.5-minute quadrangle is located in the Outer Bluegrass physiographic province (McFarlan, 1943) in the Greater Cincinnati metropolitan area of northern Kentucky and includes parts of Kenton and Campbell Counties. Topography is characterized by a relatively broad expanse of upland with moderate relief that is bounded by the Ohio River Valley, Licking River Valley, and Fourmile Creek. Gibbons (1973) mapped the bedrock geology of this quadrangle, which was later digitized by Sparks (2002). The entire quadrangle is underlain by horizontal Ordovician limestone and shale, consisting of the Point Pleasant Formation, Kope Formation, Fairview Formation, Bellevue Tongue of the Grant …


Surficial Geologic Map Of The Patriot 7.5-Minute Quadrangle, Kentucky, Maxwell L. Hammond Iii, Antonia E. Bottoms, Steven L. Martin Jan 2018

Surficial Geologic Map Of The Patriot 7.5-Minute Quadrangle, Kentucky, Maxwell L. Hammond Iii, Antonia E. Bottoms, Steven L. Martin

Contract Reports--KGS

The Patriot 7.5-minute quadrangle is located in Boone, Gallatin, and Grant Counties of northern Kentucky in the Outer Bluegrass physiographic province (McFarlan, 1943). Broad to narrow ridges, steep hillsides, and the Ohio River Valley characterize the topography of the quadrangle. The Ohio River has been made navigable by a series of high-level dams, and the Markland Locks and Dam controls the river level in this area (Ray, 1974). The bedrock geology, originally mapped by Swadley (1969), consists, from oldest to youngest, of the Point Pleasant Formation, the Kope Formation, the Fairview Formation, the Bellevue Tongue of the Grant Lake Limestone, …


Ground Motions Induced By The March 11, 2018, Implosion Of The Capital Plaza Tower, Frankfort, Kentucky, N. Seth Carpenter, Michael J. Lynch, Brandon C. Nuttall, Zhenming Wang, Andrew S. Holcomb Jan 2018

Ground Motions Induced By The March 11, 2018, Implosion Of The Capital Plaza Tower, Frankfort, Kentucky, N. Seth Carpenter, Michael J. Lynch, Brandon C. Nuttall, Zhenming Wang, Andrew S. Holcomb

Report of Investigations--KGS

The demolition by implosion of the Capital Plaza Tower in downtown Frankfort provided an opportunity to record seismic waves from a known source of seismic energy in order to observe local ground-motion amplification and resonance within the underlying unconsolidated sediment. The Kentucky Geological Survey deployed three strong-motion accelerographs at approximately equal distances around the tower to record ground motions induced by its collapse. The KGS instruments were installed at sites with different underlying geology: one on bedrock and two on Kentucky River Valley unconsolidated sediments.

Using images captured by a high-speed video camera, with timing synchronized with the clock of …


Geochronological And Geochemical Constraints On The Origin Of The Cartoogechaye Terrane, Western North Carolina: Implications For The Late Precambrian To Early Paleozoic Evolution Of The Eastern Laurentian Margin, Kevin B. Walsh Jr. Jan 2018

Geochronological And Geochemical Constraints On The Origin Of The Cartoogechaye Terrane, Western North Carolina: Implications For The Late Precambrian To Early Paleozoic Evolution Of The Eastern Laurentian Margin, Kevin B. Walsh Jr.

Theses and Dissertations--Earth and Environmental Sciences

The Cartoogechaye terrane (CT) is an enigmatic migmatite terrane within the Central Blue Ridge province of the southern Appalachians. Previous work identified exotic Pb isotope compositions within the CT (Quinn, 2012). More recent studies that mapped the extent of potentially exotic metaigneous lithologies yield U-Pb zircon ages consistent with a native Laurentian margin metasedimentary origin (Larkin, 2016). This study focused on the possible extent of similar lithologies in the Clyde quadrangle and provides further constraints on the crustal affinity of the CT. The Clyde quadrangle consists of four distinct lithologic packages: the CT, Ashe metamorphic suite, Great Smoky Group, and …


Accounting For Spatial Autocorrelation In Modeling The Distribution Of Water Quality Variables, Lorrayne Miralha Jan 2018

Accounting For Spatial Autocorrelation In Modeling The Distribution Of Water Quality Variables, Lorrayne Miralha

Theses and Dissertations--Geography

Several studies in hydrology have reported differences in outcomes between models in which spatial autocorrelation (SAC) is accounted for and those in which SAC is not. However, the capacity to predict the magnitude of such differences is still ambiguous. In this thesis, I hypothesized that SAC, inherently possessed by a response variable, influences spatial modeling outcomes. I selected ten watersheds in the USA and analyzed them to determine whether water quality variables with higher Moran’s I values undergo greater increases in the coefficient of determination (R²) and greater decreases in residual SAC (rSAC) after spatial modeling. I compared non-spatial ordinary …


Improving In-Stream Nutrient Routines In Water Quality Models Using Stable Isotope Tracers: A Review And Synthesis, Alexandria K. Jensen, William I. Ford, James F. Fox, Admin Husic Jan 2018

Improving In-Stream Nutrient Routines In Water Quality Models Using Stable Isotope Tracers: A Review And Synthesis, Alexandria K. Jensen, William I. Ford, James F. Fox, Admin Husic

Biosystems and Agricultural Engineering Faculty Publications

Water quality models serve as an economically feasible alternative to quantify fluxes of nutrient pollution and to simulate effective mitigation strategies; however, their applicability is often questioned due to broad uncertainties in model structure and parameterization, leading to uncertain outputs. We argue that reduction of uncertainty is partially achieved by integrating stable isotope data streams within the water quality model architecture. This article outlines the use of stable isotopes as a response variable within water quality models to improve the model boundary conditions associated with nutrient source provenance, constrain model parameterization, and elucidate shortcomings in the model structure. To assist …


Performance Of The Grout Curtain At The Kentucky River Lock And Dam No. 8, Robert C. Hatton Jan 2018

Performance Of The Grout Curtain At The Kentucky River Lock And Dam No. 8, Robert C. Hatton

Theses and Dissertations--Civil Engineering

Karst bedrock conditions and deterioration of the lock and dam structures have resulted in significant leakage through, underneath, and around Lock and Dam No. 8 on the Kentucky River. During severe droughts, the water surface in Pool No. 8 has been observed to drop below the crest of the dam, resulting in water supply shortages and water quality issues for surrounding communities reliant on the pool. Presently, the primary purpose of Lock and Dam No. 8 is water supply. Pool No. 8 is currently where the cities of Nicholasville (Jessamine County, KY) and Lancaster (Garrard County, KY) draw their water. …


Stratigraphy And Organic Geochemistry Reveal Patterns Of Late Quaternary Paleo-Productivity At Mono Lake, California, Bailee Nicole Hodelka Jan 2018

Stratigraphy And Organic Geochemistry Reveal Patterns Of Late Quaternary Paleo-Productivity At Mono Lake, California, Bailee Nicole Hodelka

Theses and Dissertations--Earth and Environmental Sciences

Mono Lake (CA) is a hydrologically closed lacustrine basin well-known for its paleo-shorelines, which record fluctuations in water level for the last deglacial and late Holocene. Mono Lake is a sentinel of California’s water supply, situated in the rain shadow of the Sierra Nevada, a mountain range whose snowpack is a vital source of freshwater for urban and agricultural districts to the west and south. Recent droughts, floods, and wildfires show that California is threatened by climate change, but how these changes impact and get recorded by Mono Lake sediments remains poorly known. Here, we use a new radiocarbon-dated deepwater …


Occurrence And Attributes Of Two Echinoderm-Bearing Faunas From The Upper Mississippian (Chesterian; Lower Serpukhovian) Ramey Creek Member, Slade Formation, Eastern Kentucky, U.S.A., Ann Well Harris Jan 2018

Occurrence And Attributes Of Two Echinoderm-Bearing Faunas From The Upper Mississippian (Chesterian; Lower Serpukhovian) Ramey Creek Member, Slade Formation, Eastern Kentucky, U.S.A., Ann Well Harris

Theses and Dissertations--Earth and Environmental Sciences

Well-preserved echinoderm faunas are rare in the fossil record, and when uncovered, understanding their occurrence can be useful in interpreting other faunas. In this study, two such faunas of the same age from separate localities in the shallow-marine Ramey Creek Member of the Slade Formation in the Upper Mississippian (Chesterian) rocks of eastern Kentucky are examined. Of the more than 5,000 fossil specimens from both localities, only 9–34 percent were echinoderms from 3–5 classes. Nine non-echinoderm (8 invertebrate and one vertebrate) classes occurred at both localities, but of these, bryozoans, brachiopods and sponges dominated. To understand the attributes of both …


Hydrologic Monitoring And 2-D Electrical Resistivity Imaging For Joint Geophysical And Geotechnical Characterization Of Shallow Colluvial Landslides, Matthew M. Crawford Jan 2018

Hydrologic Monitoring And 2-D Electrical Resistivity Imaging For Joint Geophysical And Geotechnical Characterization Of Shallow Colluvial Landslides, Matthew M. Crawford

Theses and Dissertations--Earth and Environmental Sciences

Landslide characterization and hazard assessments require multidisciplinary approaches that connect geologic processes with geotechnical parameters. Field monitoring of hydrologic variables such as water content and water potential, coupled with geoelectrical measurements that can establish relationships used for geotechnical and landslide hazard investigations is deficient.

This study brings together different techniques to develop a methodology that connects geoelectrical measurements and shear strength. A field-based framework was established that includes (1) analysis of long-term soil moisture fluctuations within different landslides (2) establishment of constitutive and new equations that test the use of electrical conductivity to predict soil-water relationships and shear strength (3) …


A Multi-Indicator Approach To Understanding The Diagenesis Of Carbonates In Pennsylvanian Mudrocks Of The Midland Basin, Alex J. Reis Jan 2018

A Multi-Indicator Approach To Understanding The Diagenesis Of Carbonates In Pennsylvanian Mudrocks Of The Midland Basin, Alex J. Reis

Theses and Dissertations--Earth and Environmental Sciences

The Late Pennsylvanian was a time of frequent, rapid glacioeustatic sea-level changes. These changes were recorded in the Wolfcamp D Formation of the Midland Basin as a series of cyclothems similar to those studied in the Midcontinent region (e.g., Algeo and Heckel, 2008). This study focuses on identifying the mechanisms and controls on carbonate deposition and diagenesis through the Upper Pennsylvanian Wolfcamp D Formation and evaluating the potential for these layers to be stratigraphically significant. A stepwise progression of diagenetic processes was identified through the use of δ13Ccarb and δ18Ocarb, bulk geochemical and …


Surficial Geologic Map Of The Rising Sun 7.5-Minute Quadrangle, Kentucky, Steven L. Martin, Antonia E. Bottoms, Maxwell L. Hammond Iii Jan 2018

Surficial Geologic Map Of The Rising Sun 7.5-Minute Quadrangle, Kentucky, Steven L. Martin, Antonia E. Bottoms, Maxwell L. Hammond Iii

Contract Reports--KGS

The Rising Sun 7.5-minute quadrangle is located in northern Kentucky in the Outer Bluegrass physiographic province (McFarlan, 1943). The area is underlain by Upper Ordovician limestone and shale, and is characterized by low- to medium-relief topography. The oldest rock unit in the quadrangle is the Point Pleasant Formation, which consists of interbedded limestone and shale, and is exposed at the base of the bedrock uplands area south of Lower East Bend Bottom. The shale-dominated Kope Formation overlying the Point Pleasant Formation is exposed in most stream channels and underlies the valleys and hillslopes in the quadrangle. The Kope Formation is …


Zircon U-Pb Geochronology Of Two Basement Cores (Kentucky, Usa): Implications For Late Mesoproterozoic Sedimentation And Tectonics In The Eastern Midcontinent, David P. Moecher, J. Richard Bowersox, John B. Hickman Jan 2018

Zircon U-Pb Geochronology Of Two Basement Cores (Kentucky, Usa): Implications For Late Mesoproterozoic Sedimentation And Tectonics In The Eastern Midcontinent, David P. Moecher, J. Richard Bowersox, John B. Hickman

Earth and Environmental Sciences Faculty Publications

Basement cores from two wells drilled west and east of the Grenville front consist of feldspathic litharenite and granitic orthogneiss, respectively. Detrital zircon U-Pb ages for the litharenite define a broad dominant U-Pb age mode at ca. 1115 Ma. The dominant mode matches that for the type locality of the Middle Run Formation in the Ohio subsurface and is interpreted to consist of detrital zircons sourced from East Continent Rift volcanic sources (ca. 1100 Ma) and Grenville Shawinigan granites/gneisses (1120–1180 Ma). The youngest detrital zircon ages (ca. 1020 Ma) require a maximum depositional age that is at least 70 My …


Local Loss And Spatial Homogenization Of Plant Diversity Reduce Ecosystem Multifunctionality, Yann Hautier, Forest Isbell, Elizabeth T. Borer, Eric W. Seabloom, W. Stanley Harpole, Eric M. Lind, Andrew S. Macdougall, Carly J. Stevens, Peter B. Adler, Juan Alberti, Jonathan D. Bakker, Lars A. Brudvig, Yvonne M. Buckley, Marc Cadotte, Maria C. Caldeira, Enrique J. Chaneton, Chengjin Chu, Pedro Daleo, Christopher R. Dickman, John M. Dwyer, Anu Eskelinen, Philip A Fay, Jennifer Firn, Nicole Hagenah, Helmut Hillebrand, Oscar Iribarne, Kevin P. Kirkman, Johannes M. H. Knops, Kimberly J. La Pierre, Rebecca L. Mcculley Jan 2018

Local Loss And Spatial Homogenization Of Plant Diversity Reduce Ecosystem Multifunctionality, Yann Hautier, Forest Isbell, Elizabeth T. Borer, Eric W. Seabloom, W. Stanley Harpole, Eric M. Lind, Andrew S. Macdougall, Carly J. Stevens, Peter B. Adler, Juan Alberti, Jonathan D. Bakker, Lars A. Brudvig, Yvonne M. Buckley, Marc Cadotte, Maria C. Caldeira, Enrique J. Chaneton, Chengjin Chu, Pedro Daleo, Christopher R. Dickman, John M. Dwyer, Anu Eskelinen, Philip A Fay, Jennifer Firn, Nicole Hagenah, Helmut Hillebrand, Oscar Iribarne, Kevin P. Kirkman, Johannes M. H. Knops, Kimberly J. La Pierre, Rebecca L. Mcculley

Plant and Soil Sciences Faculty Publications

Biodiversity is declining in many local communities while also becoming increasingly homogenized across space. Experiments show that local plant species loss reduces ecosystem functioning and services, but the role of spatial homogenization of community composition and the potential interaction between diversity at different scales in maintaining ecosystem functioning remains unclear, especially when many functions are considered (ecosystem multifunctionality). We present an analysis of eight ecosystem functions measured in 65 grasslands worldwide. We find that more diverse grasslands—those with both species-rich local communities (α-diversity) and large compositional differences among localities (β-diversity)—had higher levels of multifunctionality. Moreover, α- and β-diversity synergistically affected …


Can Increasing Grass-Fungal Endophyte Symbiotic Diversity Enhance Grassland Ecosystem Functioning?, Mahtaab Bagherzadeh Jan 2018

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 …


Exploring Spatial And Temporal Variability Of Soil And Crop Processes For Irrigation Management, Javier Reyes Jan 2018

Exploring Spatial And Temporal Variability Of Soil And Crop Processes For Irrigation Management, Javier Reyes

Theses and Dissertations--Plant and Soil Sciences

Irrigation needs to be applied to soils in relatively humid regions such as western Kentucky to supply water for crop uptake to optimize and stabilize yields. Characterization of soil and crop variability at the field scale is needed to apply site specific management and to optimize water application. The objective of this work is to propose a characterization and modeling of soil and crop processes to improve irrigation management. Through an analysis of spatial and temporal behavior of soil and crop variables the variability in the field was identified. Integrative analysis of soil, crop, proximal and remote sensing data was …


Probiotic Strain Stenotrophomonas Acidaminiphila Bj1 Degrades And Reduces Chlorothalonil Toxicity To Soil Enzymes, Microbial Communities And Plant Roots, Qingming Zhang, Muhammad Saleem, Caixia Wang Dec 2017

Probiotic Strain Stenotrophomonas Acidaminiphila Bj1 Degrades And Reduces Chlorothalonil Toxicity To Soil Enzymes, Microbial Communities And Plant Roots, Qingming Zhang, Muhammad Saleem, Caixia Wang

Plant and Soil Sciences Faculty Publications

Chlorothalonil, a non-systemic and broad-spectrum fungicide, is widely used to control the pathogens of agricultural plants. Although microbial degradation of chlorothalonil is known, we know little about the colonization and degradation capacity of these microbes in the natural and semi-natural soil environments. Therefore, we studied the colonization and detoxification potential of a chlorothalonil degrading Stenotrophomonas acidaminiphila probiotic strain BJ1 in the soil under green conditions. The results from polymerase chain reaction-denaturing gradient gel electrophoresis demonstrated that probiotic strain BJ1 successfully colonized the soil by competing with the native biota. Moreover, the bacterial inoculation stimulated some members of indigenous soil microbial …


Integrating Herbivore Population Dynamics Into A Global Land Biosphere Model: Plugging Animals Into The Earth System, Shree R. S. Dangal, Hanqin Tian, Chaoqun Lu, Wei Ren, Shufen Pan, Jia Yang, Nicola Di Cosmo, Amy Hessl Dec 2017

Integrating Herbivore Population Dynamics Into A Global Land Biosphere Model: Plugging Animals Into The Earth System, Shree R. S. Dangal, Hanqin Tian, Chaoqun Lu, Wei Ren, Shufen Pan, Jia Yang, Nicola Di Cosmo, Amy Hessl

Plant and Soil Sciences Faculty Publications

Mammalian herbivores are an essential component of grassland and savanna ecosystems, and with feedbacks to the climate system. To date, the response and feedbacks of mammalian herbivores to changes in both abiotic and biotic factors are poorly quantified and not adequately represented in the current global land surface modeling framework. In this study, we coupled herbivore population dynamics in a global land model (the Dynamic Land Ecosystem Model, DLEM 3.0) to simulate populations of horses, cattle, sheep, and goats, and their responses to changes in multiple environmental factors at the site level across different continents during 1980–2010. Simulated results show …