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Full-Text Articles in Life Sciences

Cooperative Evaluation Of Inner Mongolia, Prc, Grassland Germplasm In The Western Usa, J G. Scheetz, L St. John, M E. Stannard, S R. Winslow Feb 2024

Cooperative Evaluation Of Inner Mongolia, Prc, Grassland Germplasm In The Western Usa, J G. Scheetz, L St. John, M E. Stannard, S R. Winslow

IGC Proceedings (1997-2023)

Replicated dryland studies were established at three USDA, NRCS, Plant Materials Centers in the USA northern intermountain west by Chinese and American scientists. Forty-six Asian and 16 USA grasses, legumes, and shrubs were included. These plantings were evaluated for vigor, percent stand, and foliage height in 1994 and 1995, and for biomass production in 1995. Generally, USA grasses outperformed Asian grasses, while Inner Mongolian legumes show the highest potential for use in the intermountain west.


Description Of A New Species Of Crossidius Leconte (Coleoptera: Cerambycidae: Cerambycinae: Trachyderini) From Texas, Frederick W. Skillman Jr. Mar 2023

Description Of A New Species Of Crossidius Leconte (Coleoptera: Cerambycidae: Cerambycinae: Trachyderini) From Texas, Frederick W. Skillman Jr.

Insecta Mundi

Crossidius wappesi Skillman, new species (Coleoptera: Cerambycidae) is described from Presidio County, Texas, USA.

I discovered a new species of Crossidius LeConte (Cerambycinae) in the fall of 2018 while collecting with Jim Wappes in Presidio County, Texas. Additional specimens were collected at the same location in 2019 by Jim Wappes and Kenneth Kuckartz.

This large, predominately western trachyderine genus presently contains 17 species and 37 subspecies (Bezark 2022). It should be noted that in the study of the genus by Linsley and Chemsak (1961), numerous popu­lations, known from short series, were mentioned, given short descriptions and left nameless. It is …


Why Are There So Many Mosquitoes?, Alan L. Gillen, Savannah Childs, Megan Goin, Karly Mckinney Jun 2022

Why Are There So Many Mosquitoes?, Alan L. Gillen, Savannah Childs, Megan Goin, Karly Mckinney

Faculty Publications and Presentations

Mosquitoes have been challenging man and animals alike since the fall.Mosquitoes number in the trillions worldwide. Not only is the mosquito a nuisance with the constant buzz around your ear, they also are the primary vector of many dangerous diseases including the West Nile Virus (WNV). WNV has become a more prominent mosquito-transmitted disease in the United States and more specifically in Colorado, Texas, and other states in the Midwest. While commonly found in the genus Culex, WNV and other diseases can be found in differentgenera of mosquito, including Aedes and Anopheles. While these two are not themost common regarding …


Kentucky’S Comprehensive Outreach Program For Horse Pasture Management And Education, Krista Lea, S. Ray Smith Feb 2022

Kentucky’S Comprehensive Outreach Program For Horse Pasture Management And Education, Krista Lea, S. Ray Smith

IGC Proceedings (1997-2023)

The University of Kentucky (UK) Horse Pasture Evaluation Program began in 2005 to improve pasture quality and quantity on Kentucky horse farms. This on-farm program collects detailed data of pasture species composition, tests for tall fescue (Schedonorus arundinaceus (Schreb.) Dumort.) toxicity, and provides farm managers with comprehensive recommendations for management. Species composition is determined using the occupancy method. In 2019, the UK Horse Pasture Health Score Card was developed to provide useful, survey-level information on pastures and allow evaluators to cover far more acres in less time, requiring fewer resources. The objective of this research was to compare accuracy …


Practice Cost And Size Differences In Invasive Plant Management Strategies: An Empirical Analysis Of Us Great Plains States, Mazbahul G. Ahamad Feb 2022

Practice Cost And Size Differences In Invasive Plant Management Strategies: An Empirical Analysis Of Us Great Plains States, Mazbahul G. Ahamad

Department of Agronomy and Horticulture: Faculty Publications

Grassland conservation of the Conservation Stewardship Program in the United States (US) is one of the largest cost-sharing initiatives for protecting grazing land from invasive and woody plants. The practice cost and unit size of various invasive and woody plant management strategies, such as mulching, brush management, and pre- scribed burning, are different from state to state. We aimed to compare and examine the association between practice cost ($/acre[ac]) and standard unit size of practice (acre) of mulching, brush management, and pre- scribed burning strategies in nine US Great Plains states, including Kansas, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, …


Study On Post Approval Source Change Of Active Pharmaceutical Ingredient In The Finished Product And Its Regulatory Requirements In Eu And Us, Kalpana Kamnoore, M. P. Venkatesh, T.M. Pramod Kumar Jan 2022

Study On Post Approval Source Change Of Active Pharmaceutical Ingredient In The Finished Product And Its Regulatory Requirements In Eu And Us, Kalpana Kamnoore, M. P. Venkatesh, T.M. Pramod Kumar

The Thai Journal of Pharmaceutical Sciences

Post approval changes are changes to any characteristic of pharmaceutical product after approval. Certificate of suitability of European pharmacopoeia (CEP) and drug master file (DMF) are two mechanisms for active pharmaceutical ingredient (API) registration. Regulatory requirements vary for each mechanism. This study focused on regulatory requirements for post approval API source change in the European Union (EU) and USA; and to delve on the mechanism of post approval API source changes in the USA and EU. To improve quality of the API, the most of the pharmaceutical industries concentrate on CEP certified source instead of DMF as CEP assures compliance …


Insignificant Impacts Of Covid-19 Stay-At-Home Orders On Chicago Air Quality, Adam W.T. Steffeck Aug 2021

Insignificant Impacts Of Covid-19 Stay-At-Home Orders On Chicago Air Quality, Adam W.T. Steffeck

DePaul Discoveries

With the onset of the COVID-19 pandemic, reports of air quality improvements around the world resulting from the stay-at-home orders were widespread. However, for Chicago, no significant air quality improvements occurred despite large reductions in private vehicle transportation due to the lack of commuters. The city of Chicago is a nexus for long-haul transportation by trucks and trains, which did not decrease during the pandemic. These transportation sources use mostly diesel fuel engines and emit NOX, a precursor to tropospheric ozone, and PM2.5, both of which are harmful air pollutants. Using open access EPA air quality …


On The Transference Of Ataxia Tibialis Schaeffer To Bisaltes (Bisaltes) Thomson With Synonymies And New Records In The Genus (Coleoptera: Cerambycidae), Antonio Santos-Silva, James E. Wappes Jan 2021

On The Transference Of Ataxia Tibialis Schaeffer To Bisaltes (Bisaltes) Thomson With Synonymies And New Records In The Genus (Coleoptera: Cerambycidae), Antonio Santos-Silva, James E. Wappes

Insecta Mundi

Ataxia tibialis Schaeffer, 1908 (Coleoptera: Cerambycidae: Lamiinae: Pteropliini) is transferred to Bisaltes (Bisaltes) Thomson, 1868 (Apomecynini), new combination; the female is described for the first time. This extends the range of the genus, previously only known as far north as Costa Rica, to southern Texas. Bisaltes (Bisaltes) obliquatus Breuning, 1940 is found to be conspecific with Bisaltes (Bisaltes) uniformis Breuning, 1939, new synonymy, and recorded from Argentina and the Brazilian state of São Paulo. The ho­lotypes of Esthlogena pulverea Bates, 1866, and Bisaltes posticalis Thomson, 1868 (currently, both synonyms of Bisaltes (Bisaltes …


Future Dominance By Quaking Aspen Expected Following Short-Interval, Compounded Disturbance Interaction, Robert A. Andrus, Sarah J. Hart, Niko Tutland, Thomas T. Veblen Jan 2021

Future Dominance By Quaking Aspen Expected Following Short-Interval, Compounded Disturbance Interaction, Robert A. Andrus, Sarah J. Hart, Niko Tutland, Thomas T. Veblen

Aspen Bibliography

The spatial overlap of multiple ecological disturbances in close succession has the capacity to alter trajectories of ecosystem recovery. Widespread bark beetle outbreaks and wildfire have affected many forests in western North America in the past two decades in areas of important habitat for native ungulates. Bark beetle outbreaks prior to fire may deplete seed supply of the host species, and differences in fire‐related regeneration strategies among species may shift the species composition and structure of the initial forest trajectory. Subsequent browsing of postfire tree regeneration by large ungulates, such as elk (Cervus canadensis), may limit the capacity …


Dispersal And Land Cover Contribute To Pseudorabies Virus Exposure In Invasive Wild Pigs, Felipe A. Hernandez, Amanda N. Carr, Michael P. Milleson, Hunter R. Merrill, Michael L. Avery, Brandon M. Parker, Cortney L. Pylant, James D. Austin, Samantha M. Wisely Jan 2021

Dispersal And Land Cover Contribute To Pseudorabies Virus Exposure In Invasive Wild Pigs, Felipe A. Hernandez, Amanda N. Carr, Michael P. Milleson, Hunter R. Merrill, Michael L. Avery, Brandon M. Parker, Cortney L. Pylant, James D. Austin, Samantha M. Wisely

USDA Wildlife Services: Staff Publications

We investigated the landscape epidemiology of a globally distributed mammal, the wild pig (Sus scrofa), in Florida (U.S.), where it is considered an invasive species and reservoir to pathogens that impact the health of people, domestic animals, and wildlife. Specifically, we tested the hypothesis that two commonly cited factors in disease transmission, connectivity among populations and abundant resources, would increase the likelihood of exposure to both pseudorabies virus (PrV) and Brucella spp. (bacterial agent of brucellosis) in wild pigs across the Kissimmee Valley of Florida. Using DNA from 348 wild pigs and sera from 320 individuals at 24 sites, we …


Peptide Elisa And Fret-Qpcr Identified A Significantly Higher Prevalence Of Chlamydia Suis In Domestic Pigs Than In Feral Swine From The State Of Alabama, Usa, Md Monirul Hoque, Folasade Adekanmbi, Subarna Barua, Kh. Shamsur Rahman, Virginia Aida, Brian Anderson, Anil Poudel, Anwar Kalalah, Sara Bolds, Steven Madere, Steven Kitchens, Stuart Price, Vienna Brown, B. Graeme Lockaby, Constantinos S. Kyriakis, Bernhard Kaltenboeck, Chengming Wang Jan 2021

Peptide Elisa And Fret-Qpcr Identified A Significantly Higher Prevalence Of Chlamydia Suis In Domestic Pigs Than In Feral Swine From The State Of Alabama, Usa, Md Monirul Hoque, Folasade Adekanmbi, Subarna Barua, Kh. Shamsur Rahman, Virginia Aida, Brian Anderson, Anil Poudel, Anwar Kalalah, Sara Bolds, Steven Madere, Steven Kitchens, Stuart Price, Vienna Brown, B. Graeme Lockaby, Constantinos S. Kyriakis, Bernhard Kaltenboeck, Chengming Wang

USDA Wildlife Services: Staff Publications

Chlamydia suis is an important, highly prevalent, and diverse obligate intracellular pathogen infecting pigs. In order to investigate the prevalence and diversity of C. suis in the U.S., 276 whole blood samples from feral swine were collected as well as 109 fecal swabs and 60 whole blood samples from domestic pigs. C. suis-specific peptide ELISA identified anti-C. suis antibodies in 13.0% of the blood of feral swine (26/276) and 80.0% of the domestic pigs (48/60). FRET-qPCR and DNA sequencing found C. suis DNA in 99.1% of the fecal swabs (108/109) and 21.7% of the whole blood (13/60) of …


Love Of Life In Nine Developed And Underdevelopedcountries, Ahmed Abdel-Khalek Professor Of Psychology, Faculty Of Arts,, Mayssah El Nayal Professor Of Psychology, Faculty Of Human Sciences Sep 2020

Love Of Life In Nine Developed And Underdevelopedcountries, Ahmed Abdel-Khalek Professor Of Psychology, Faculty Of Arts,, Mayssah El Nayal Professor Of Psychology, Faculty Of Human Sciences

BAU Journal - Health and Wellbeing

The present research sought to explore the differences between developed and underdeveloped countries on the Love of Life Scale (LLS). Nine samples (N =3,799) took part in the study. They were university students from Egypt, Lebanon, Kuwait, Qatar, Algeria, Malaysia, India, Iran, and USA. Sex-related differences in LLS were significant only in Kuwait (in favor of males) and India (in favor of females). The samples of Malaysia and U.S.A. obtained the highest mean LLS score, followed by participants from Qatar, India, and Kuwait, (males), and India, Iran, Qatar, and Algeria (females), respectively. The Pearson correlation of LLS with the World …


Protecting Endangered Species In The Usa Requires Both Public And Private Land Conservation, Niall G. Clancy, John P. Draper, J. Marshall Wolf, Umarfarooq A. Abdulwahab, Maya Cassidy Pendleton, Soren Brothers, Janice Brahney, Jennifer M. Weathered, Edd Hammill, Trisha B. Atwood Jul 2020

Protecting Endangered Species In The Usa Requires Both Public And Private Land Conservation, Niall G. Clancy, John P. Draper, J. Marshall Wolf, Umarfarooq A. Abdulwahab, Maya Cassidy Pendleton, Soren Brothers, Janice Brahney, Jennifer M. Weathered, Edd Hammill, Trisha B. Atwood

Ecology Center Publications

Crucial to the successful conservation of endangered species is the overlap of their ranges with protected areas. We analyzed protected areas in the continental USA to assess the extent to which they covered the ranges of endangered tetrapods. We show that in 80% of ecoregions, protected areas offer equal (25%) or worse (55%) protection for species than if their locations were chosen at random. Additionally, we demonstrate that it is possible to achieve sufficient protection for 100% of the USA’s endangered tetrapods through targeted protection of undeveloped public and private lands. Our results highlight that the USA is likely to …


Protecting Endangered Species In The Usa Requires Both Public And Private Land Conservation, Niall G. Clancy, John P. Draper, J. Marshall Wolf, Umarfarooq A. Abdulwahab, Maya C. Pendleton, Soren Brothers, Janice Brahney, Jennifer Weathered, Edd Hammill, Trisha B. Atwood Jul 2020

Protecting Endangered Species In The Usa Requires Both Public And Private Land Conservation, Niall G. Clancy, John P. Draper, J. Marshall Wolf, Umarfarooq A. Abdulwahab, Maya C. Pendleton, Soren Brothers, Janice Brahney, Jennifer Weathered, Edd Hammill, Trisha B. Atwood

All Publications

Crucial to the successful conservation of endangered species is the overlap of their ranges with protected areas. We analyzed protected areas in the continental USA to assess the extent to which they covered the ranges of endangered tetrapods. We show that in 80% of ecoregions, protected areas offer equal (25%) or worse (55%) protection for species than if their locations were chosen at random. Additionally, we demonstrate that it is possible to achieve sufficient protection for 100% of the USA’s endangered tetrapods through targeted protection of undeveloped public and private lands. Our results highlight that the USA is likely to …


Beyond Bird Feed: Proso Millet For Human Health And Environment, Saurav Das, Rituraj Khound, Meenakshi Santra, Dipak K. Santra Jan 2019

Beyond Bird Feed: Proso Millet For Human Health And Environment, Saurav Das, Rituraj Khound, Meenakshi Santra, Dipak K. Santra

Department of Agronomy and Horticulture: Faculty Publications

Domesticated in 8000–10,000 BP in northern China, proso millet (Panicum miliaceum L.) is the best adaptive rotational crop for semiarid central High Plains of the USA, where average annual precipitation is 356–407 mm. Proso millet has multiple benefits when consumed as human food. Proso millet is rich in minerals, dietary fiber, polyphenols, vitamins and proteins. It is gluten-free and therefore, ideal for the gluten intolerant people. Proso millet contains high lecithin which supports the neural health system. It is rich in vitamins (niacin, B-complex vitamins, folic acid), minerals (P, Ca, Zn, Fe) and essential amino acids (methionine and cysteine). …


Measuring, Mapping And Quantifying The Effects Of Trust And Informal Communication On Transboundary Collaboration In The Great Lakes Fisheries Policy Network, Andrew M. Song, Owen Temby, Dongkyu Kim, Angel Saavedra Cisneros, Gordon M. Hickey Jan 2019

Measuring, Mapping And Quantifying The Effects Of Trust And Informal Communication On Transboundary Collaboration In The Great Lakes Fisheries Policy Network, Andrew M. Song, Owen Temby, Dongkyu Kim, Angel Saavedra Cisneros, Gordon M. Hickey

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Ecosystem-based management of fisheries and other transboundary natural resources require a number of organizations across jurisdictions to exchange knowledge, coordinate policy goals and engage in collaborative activities. Trust, as part of social capital, is considered a key mechanism facilitating the coordination of such inter-organizational policy networks. However, our understanding of multi-dimensional trust as a theoretical construct and an operational variable in environmental and natural resource management has remained largely untested. This paper presents an empirical assessment of trust and communication measures applied to the North American Great Lakes fisheries policy network. Using a scale-based method developed for this purpose, we …


Floristic Survey Of Crawford And Cherokee Counties In Southeast Kansas: An Evaluation Of Change Over Five Decades, Samantha Pryer Jul 2018

Floristic Survey Of Crawford And Cherokee Counties In Southeast Kansas: An Evaluation Of Change Over Five Decades, Samantha Pryer

Electronic Theses & Dissertations

This project had two main objectives. The first objective was to document comprehensively the vascular flora of Crawford and Cherokee counties in extreme southeast Kansas. Each county had seen limited collecting in recent decades, though a comprehensive survey had never been done for Cherokee County. PSU student E.S. Gibson summarized the flora for Crawford County in 1963. Fieldwork for the present study occurred mostly in 2014 and 2015. Based on 6500+ newly collected specimens, vouchers from Gibson’s study, and taxa documented by Biota of North America (BONAP) (Kartesz 2017), 1440 taxa are reported, which includes 33 state and 263 county …


Slides: Environmental Flows In The Era Of 'River Anthropology', Rebecca Tharme Jun 2016

Slides: Environmental Flows In The Era Of 'River Anthropology', Rebecca Tharme

Coping with Water Scarcity in River Basins Worldwide: Lessons Learned from Shared Experiences (Martz Summer Conference, June 9-10)

Presenter: Rebecca Tharme, Riverfutures Ltd.

18 slides


The Removal Kinetics Of Dissolved Organic Matter And The Optical Clarity Of Groundwater, Francis H. Chapelle, Yuan Shen, Eric W. Strom, Ronald Benner Apr 2016

The Removal Kinetics Of Dissolved Organic Matter And The Optical Clarity Of Groundwater, Francis H. Chapelle, Yuan Shen, Eric W. Strom, Ronald Benner

Faculty Publications

Concentrations of dissolved organic matter (DOM) and ultraviolet/visible light absorbance decrease systematically as groundwater moves through the unsaturated zones overlying aquifers and along flowpaths within aquifers. These changes occur over distances of tens of meters (m) implying rapid removal kinetics of the chromophoric DOM that imparts color to groundwater. A one-compartment input-output model was used to derive a differential equation describing the removal of DOM from the dissolved phase due to the combined effects of biodegradation and sorption. The general solution to the equation was parameterized using a 2-year record of dissolved organic carbon (DOC) concentration changes in groundwater at …


Convergence Of Detrital Stoichiometry Predicts Thresholds Of Nutrient-Stimulated Breakdown In Streams, David W. P. Manning, Amy D. Rosemond, Vladislav Gulis, Jonathan P. Benstead, John S. Kominoski, John C. Maerz Jan 2016

Convergence Of Detrital Stoichiometry Predicts Thresholds Of Nutrient-Stimulated Breakdown In Streams, David W. P. Manning, Amy D. Rosemond, Vladislav Gulis, Jonathan P. Benstead, John S. Kominoski, John C. Maerz

Biology Faculty Publications

Nutrient enrichment of detritus‐based streams increases detrital resource quality for consumers and stimulates breakdown rates of particulate organic carbon (C). The relative importance of dissolved inorganic nitrogen (N) vs. phosphorus (P) for detrital quality and their effects on microbial‐ vs. detritivore‐mediated detrital breakdown are poorly understood. We tested effects of experimental N and P additions on detrital stoichiometry (C:N, C:P) and total and microbial breakdown (i.e., with and without detritivorous shredders, respectively) of five detritus types (four leaf litter species and wood) with different initial C : nutrient content. We enriched five headwater streams continuously for two years at different …


Elevated Co2 Induced Changes In The Chemistry Of Quaking Aspen (Populus Tremuloides Michaux) Leaf Litter: Subsequent Mass Loss And Microbial Response In A Stream Ecosystem, Steven Rier, Nancy Tuchman, Robert Wetzel, James Teeri Dec 2015

Elevated Co2 Induced Changes In The Chemistry Of Quaking Aspen (Populus Tremuloides Michaux) Leaf Litter: Subsequent Mass Loss And Microbial Response In A Stream Ecosystem, Steven Rier, Nancy Tuchman, Robert Wetzel, James Teeri

Nancy Tuchman

No abstract provided.


Use And Selection Of Sap Trees By Yellow-Bellied Sapsuckers, Laurie Eberhardt Dec 2015

Use And Selection Of Sap Trees By Yellow-Bellied Sapsuckers, Laurie Eberhardt

Laurie Eberhardt

No abstract provided.


Grass-Shrub Associations Over A Precipitation Gradient And Their Implications For Restoration In The Great Basin, Usa, Maike F. Holthuijzen, Kari E. Veblen Dec 2015

Grass-Shrub Associations Over A Precipitation Gradient And Their Implications For Restoration In The Great Basin, Usa, Maike F. Holthuijzen, Kari E. Veblen

Wildland Resources Faculty Publications

As environmental stress increases positive (facilitative) plant interactions often predominate. Plant-plant associations (or lack thereof) can indicate whether certain plant species favor particular types of microsites (e.g., shrub canopies or plant-free interspaces) and can provide valuable insights into whether “nurse plants” will contribute to seeding or planting success during ecological restoration. It can be difficult, however, to anticipate how relationships between nurse plants and plants used for restoration may change over large-ranging, regional stress gradients. We investigated associations between the shrub, Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis), and three common native grasses (Poa secunda, Elymus elymoides, and Pseudoroegneria spicata), …


Spatial Aspects Of Tree Mortality Strongly Differ Between Young And Old-Growth Forests, Andrew J. Larson, James A. Lutz, Daniel C. Donato, James A. Freund, Mark E. Swanson, Janneke Hillrislambers, Douglas G. Sprugel, Jerry F. Franklin Nov 2015

Spatial Aspects Of Tree Mortality Strongly Differ Between Young And Old-Growth Forests, Andrew J. Larson, James A. Lutz, Daniel C. Donato, James A. Freund, Mark E. Swanson, Janneke Hillrislambers, Douglas G. Sprugel, Jerry F. Franklin

Forest Management Faculty Publications

Rates and spatial patterns of tree mortality are predicted to change during forest structural development. In young forests, mortality should be primarily density dependent due to competition for light, leading to an increasingly spatially uniform pattern of surviving trees. In contrast, mortality in old-growth forests should be primarily caused by contagious and spatially auto-correlated agents (e.g., insects, wind), causing spatial aggregation of surviving trees to increase through time. We tested these predictions by contrasting a three-decade record of tree mortality from replicated mapped permanent plots located in young (<60-year-old) and old-growth (>300-year-old) Abies amabilis forests. Trees in young forests died at a …


Investigations And Management Of Epizootic Plague At Ice House Reservoir, Eldorado National Forest, California, 1994 And 1995, Kenneth R. Townzen, Malcolm A. Thompson, Charles R. Smith Jun 2015

Investigations And Management Of Epizootic Plague At Ice House Reservoir, Eldorado National Forest, California, 1994 And 1995, Kenneth R. Townzen, Malcolm A. Thompson, Charles R. Smith

Charles Kay Smith

The occurrence of plague (Yersinia pestic) at Ice House Reservoir in 1994 and 1995 was characteristic of widespread epizootics in high use recreational areas of California. Staff of the Vector-Borne Disease Section investigated these epizootics and found dense populations of plague susceptible California ground squirrels (Spermophilus beecheyi) with high numbers of fleas, primarily Diamanus montanus, the most important plague vector. This combination indicated a high risk of plague exposure to campground users. A non-fatal human case of plague, contracted at Mountain Camp II, was reported after the initial epizootic investigation. The patient's exposure occurred prior to the reporting of the …


Grass-Shrub Spatial Associations Over Precipitation And Grazing Gradients In The Great Basin, Usa, Maike F. Holthuijzen May 2015

Grass-Shrub Spatial Associations Over Precipitation And Grazing Gradients In The Great Basin, Usa, Maike F. Holthuijzen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As environmental stress increases, positive plant interactions dominate, resulting in clumped, plant-plant spatial patterns. Positive plant-plant interactions have received more attention in recent years due to their importance to the structure and function of arid ecosystems. Certain plants (nurses), provide benefits that help neighboring plants grow or survive.

I investigated spatial associations between Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) and three native grasses (Poa secunda, Elymus elymoides, and Pseudoroegnaria spicata) across a rainfall gradient in the Great Basin, USA. We also explored the effect of grazing on grass-shrub spatial patterns. I hypothesized that positive …


Identification Of Root-Knot Nematodes (Meloidogyne Spp.) Of Arkansas Using Molecular Diagnostics, Churamani Khanal Dec 2014

Identification Of Root-Knot Nematodes (Meloidogyne Spp.) Of Arkansas Using Molecular Diagnostics, Churamani Khanal

Graduate Theses and Dissertations

Root-knot nematodes (Meloidogyne spp.) are highly-adaptable, obligate plant parasites distributed worldwide. In addition, root-knot nematodes are an economically important genus of plant-parasitic nematodes. Meloidogyne incognita, M. arenaria, M. javanica, M. hapla and M. graminis have been reported from Arkansas during 1964 to 1994. Previous identifications were based primarily on morphological characters and host differentials. In this study, identification using molecular diagnostics methods was performed to identify Meloidogyne species present in Arkansas. A total of 106 soil and root samples from 36 of the 75 counties were collected and processed to obtain root-knot nematodes. Polymerase chain reaction (PCR) was performed …


Breeding Time In A Migratory Songbird Is Predicted By Drought Severity And Group Size, Charles R. Brown, Mary Bomberger Brown Oct 2014

Breeding Time In A Migratory Songbird Is Predicted By Drought Severity And Group Size, Charles R. Brown, Mary Bomberger Brown

School of Natural Resources: Faculty Publications

Global climate change is altering the breeding phenology of many organisms, and one reported consequence of warmer average temperatures is earlier breeding times in migratory songbirds of north temperate latitudes. Less studied are the potential interactions between earlier breeding and social behavior in colonial species. We investigated how breeding time, as measured by colony initiation dates across the entire summer, in Cliff Swallows (Petrochelidon pyrrhonota) of southwestern Nebraska, USA, changed over a 30-year period and could be predicted by climatic variables, year, and colony size. Mean colony initiation date became earlier over the study, with variation best predicted …


Can Fire Atlas Data Improve Species Distribution Model Projections?, Shawn M. Crimmins, Solomon Z. Dobrowski, Alison R. Mynsberge, Hugh D. Safford Jul 2014

Can Fire Atlas Data Improve Species Distribution Model Projections?, Shawn M. Crimmins, Solomon Z. Dobrowski, Alison R. Mynsberge, Hugh D. Safford

Forest Management Faculty Publications

Correlative species distribution models (SDMs) are widely used in studies of climate change impacts, yet are often criticized for failing to incorporate disturbance processes that can influence species distributions. Here we use two temporally independent data sets of vascular plant distributions, climate data, and fire atlas data to examine the influence of disturbance history on SDM projection accuracy through time in the mountain ranges of California, USA. We used hierarchical partitioning to examine the influence of fire occurrence on the distribution of 144 vascular plant species and built a suite of SDMs to examine how the inclusion of fire-related predictors …


Granivory Of Invasive, Naturalized, And Native Plants In Communities Differentially Susceptible To Invasion, B. M. Connolly, Dean Pearson, R. N. Mack Jul 2014

Granivory Of Invasive, Naturalized, And Native Plants In Communities Differentially Susceptible To Invasion, B. M. Connolly, Dean Pearson, R. N. Mack

Biological Sciences Faculty Publications

Seed predation is an important biotic filter that can influence abundance and spatial distributions of native species through differential effects on recruitment. This filter may also influence the relative abundance of nonnative plants within habitats and the communities’ susceptibility to invasion via differences in granivore identity, abundance, and food preference. We evaluated the effect of postdispersal seed predators on the establishment of invasive, naturalized, and native species within and between adjacent forest and steppe communities of eastern Washington, USA that differ in severity of plant invasion. Seed removal from trays placed within guild-specific exclosures revealed that small mammals were the …