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Effects Of Site Preparation, Seed Germination, And Harvest Maturity On Wiregrass Restoration Efforts At Fort Stewart, Ga, Nickey Garrett Anderson Jan 2013

Effects Of Site Preparation, Seed Germination, And Harvest Maturity On Wiregrass Restoration Efforts At Fort Stewart, Ga, Nickey Garrett Anderson

College of Graduate Studies: Theses & Dissertations

Wiregrass (Aristida stricta Michx.) was once the dominant ground cover species within the Atlantic Coastal Plain longleaf pine (Pinus palustris Mill.) ecosystem. Less than 1 million hectares of intact longleaf pine-wiregrass communities remain, due primarily to anthropogenic activities. Wiregrass is a keystone species in the longleaf pine ecosystem, as its presence facilitates the natural fire regime, a critical component in the perpetuation of these communities. Therefore, there is increased interest in wiregrass restoration in both existing longleaf pine communities and future longleaf pine restoration sites. Many restoration sites are on tracts that have been cleared of all vegetation. Removal of …

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Walleye Trophic Position Before And After A Gizzard Shad Extirpation, Bethany J. Bethke, Justin A. Vandehey, Mark J. Fincel, Brian D.S. Graeb, Mark T. Porath Dec 2012

Walleye Trophic Position Before And After A Gizzard Shad Extirpation, Bethany J. Bethke, Justin A. Vandehey, Mark J. Fincel, Brian D.S. Graeb, Mark T. Porath

The Prairie Naturalist

Walleye (Sander vitreus) are an ecologically and recreationally important sport fish species. Reduced growth and condition in walleye can occur when prey availability is limited. In two Nebraska reservoirs, walleye consumed gizzard shad (Dorosoma cepedianum) as their primary prey until a winterkill extirpated the gizzard shad in 2001. Because of the winterkill, walleye in the two reservoirs had to change to alternative prey items. Our objective was to determine if stable isotope analysis on archived walleye scales can be used to detect a known food web shift in two reservoir food webs. We quantified the changes …

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Community Structure And Ecological Specialization In Plant-Ant Interactions, Paola Barriga Dec 2012

Community Structure And Ecological Specialization In Plant-Ant Interactions, Paola Barriga

Graduate Theses and Dissertations

Positive associations among species have contributed to the maintenance of biodiversity. These interactions are typically studied in pairwise fashion where two interacting organisms are the focus. This dissertation uses network theory to analyze positive plant-ant associations in three Neotropical forests. Obligate plant-ant mutualisms were used, where plants host the ants in domatia and provide food bodies while the ants protect the plants and can feed them. A network approach was used to depict all obligate plant-ant interactions within a community. The main questions asked at the community level were: 1) Do network structure and levels of specialization change geographically and, …

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Challenges In Predicting The Future Distributions Of Invasive Plant Species, Chad C. Jones Nov 2012

Challenges In Predicting The Future Distributions Of Invasive Plant Species, Chad C. Jones

Botany Faculty Publications

Species distribution models (SDMs) are increasingly used to predict distributions of invasive species. If successful, these models can help managers target limited resources for monitoring and controlling invasive species to areas of high invasion risk. Model accuracy is usually determined using current species distributions, but because invasive species are not at equilibrium with the environment, high current accuracy may not indicate high future accuracy. I used 1982 species distribution data from Bolleswood Natural Area, Connecticut, USA, to create SDMs for two forest invaders, Celastrus orbiculatus and Rosa multiflora. I then used more recent data, from 1992 and 2002, as validation …

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Naturalization Of Sequoiadendron Giganteum (Cupressaceae) In Montane Southern California, Rudolf Schmid, Mena Schmid Sep 2012

Naturalization Of Sequoiadendron Giganteum (Cupressaceae) In Montane Southern California, Rudolf Schmid, Mena Schmid

Aliso: A Journal of Systematic and Floristic Botany

After the August 1974 fire in the upper Hall Canyon area on the southwestern flank of Black Mountain in the northwestern San Jacinto Mountains, Riverside County, California, the United States Forest Service revegetated the burn in the mixed-conifer forest with the Sierra Nevada endemic Sequoiadendron giganteum (Cupressaceae). On 1 May 2009 a GPS census starting at the head of Hall Canyon revealed both in the canyon and upslope beyond it at least 157 individuals in the vicinity of the Black Mountain Trail, plus an outlier 450 m distant near the summit. This species alien to southern California is regenerating prolifically …

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Genetic Diversity, Pathogenicity/Virulence Variation And Population Structure Of Rhizoctonia Spp. Associated With Rice Sheath Blight In Arkansas And Qtl Mapping For Disease Resistance, Vanina Lilian Castroagudin Aug 2012

Genetic Diversity, Pathogenicity/Virulence Variation And Population Structure Of Rhizoctonia Spp. Associated With Rice Sheath Blight In Arkansas And Qtl Mapping For Disease Resistance, Vanina Lilian Castroagudin

Graduate Theses and Dissertations

Rice sheath blight (ShB) is one of the most prevalent diseases in rice. The significance of this disease is increasing due to more intensive production practices globally. Rhizoctonia solani Kühn AG 1 - IA [teleomorph: Thanatephorus cucumeris (A.B. Frank) Donk] is considered the primary ShB pathogen of rice. However, Rhizoctonia oryzae-sativae, Rhizoctonia oryzae, and R. solani AG 2 and AG 11, have also been isolated from sheath blight-like lesions on rice.Up to now, there is little information on genetic diversity and patterns of molecular evolution of the fungus, and there is no study on the structure of the R. solani …

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Seasonal Population Dynamics Of The Potato Psyllid (Hemiptera: Triozidae) And Its Associated Pathogen “Candidatus Liberibacter Solanacearum” In Potatoes In The Southern Great Plains Of North America, John A. Goolsby, John J. Adamczyk Jr., J. M. Crosslin, Noel N. Troxclair, J. R. Ancisco, Gerhard G. Bester, J. D. Bradshaw, Edsel D. Bynum Jr., L. A. Carpio, Don C. Henne, Ankush Joshi, Joseph E. Munyaneza, Pat Porter, Phillip E. Sloderbeck, J. R. Supak, C. M. Rush, F. J. Willett, B. J. Zechmann, B. A. Zens Aug 2012

Seasonal Population Dynamics Of The Potato Psyllid (Hemiptera: Triozidae) And Its Associated Pathogen “Candidatus Liberibacter Solanacearum” In Potatoes In The Southern Great Plains Of North America, John A. Goolsby, John J. Adamczyk Jr., J. M. Crosslin, Noel N. Troxclair, J. R. Ancisco, Gerhard G. Bester, J. D. Bradshaw, Edsel D. Bynum Jr., L. A. Carpio, Don C. Henne, Ankush Joshi, Joseph E. Munyaneza, Pat Porter, Phillip E. Sloderbeck, J. R. Supak, C. M. Rush, F. J. Willett, B. J. Zechmann, B. A. Zens

Department of Entomology: Faculty Publications

The potato psyllid, Bactericera cockerelli (Sulc) (Hemiptera: Triozidae), and its associated pathogen “Candidatus Liberibacter solanacearum” (Ca. L. solanacearum), the putative causal agent of zebra chip (ZC) disease in potatoes (Solanum tuberosum L.), were sampled in commercial potato fields and untreated control plots for 3 yr in multiple locations in Texas, Kansas, Nebraska, and Colorado. Populations of the potato psyllid varied across years and across potato growing regions. However, the percentage of potato psyllids infected with Ca. L. solanacearum although variable across years, was consistently highest in the Lower Rio Grande Valley of Texas (LRGV), the reported overwintering …

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Five New Records Of Ants (Hymenoptera: Formicidae) For Nebraska, Kristine T. Nemec, James C. Trager, Elizabeth Manley, Craig R. Allen Jun 2012

Five New Records Of Ants (Hymenoptera: Formicidae) For Nebraska, Kristine T. Nemec, James C. Trager, Elizabeth Manley, Craig R. Allen

The Prairie Naturalist

Ants are ubiquitous and influential organisms in terrestrial ecosystems. About 1,000 ant species occur in North America, where they are found in nearly every habitat (Fisher and Cover 2007). Ants are critical to ecological processes and structure. Ants affect soils via tunneling activity (Baxter and Hole 1967), disperse plant seeds (Lengyel et al. 2009), prey upon a variety of insects and other invertebrates (Way and Khoo 1992, Folgarait 1998), are often effective primary consumers through their prodigious consumption of floral and especially extrafloral nectar, and honeydew (Tobin 1994), and serve as prey for invertebrates (Gotelli 1996, Gastreich 1999) and vertebrates …

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Spatial Ecology Of Urban Raccoons In Northeastern Ohio: Implications For Oral Rabies Vaccination, Are R. Berentsen, Mike R. Dunbar, Chadd E. Fitzpatrick, W. David Walter Jun 2012

Spatial Ecology Of Urban Raccoons In Northeastern Ohio: Implications For Oral Rabies Vaccination, Are R. Berentsen, Mike R. Dunbar, Chadd E. Fitzpatrick, W. David Walter

The Prairie Naturalist

In 1977, rabies was detected in a raccoon (Procyon lotor) in West Virginia, and since the mid-1980s raccoon variant rabies has spread throughout the eastern United States and moved west as far as the eastern edge of Cleveland, Ohio. The primary tool to combat this spread is the distribution of oral rabies vaccine (ORV) baits. A thorough knowledge of raccoon space use is critical in determining bait placement, particularly in urban areas. We monitored nine raccoons in urban areas of Cleveland, Ohio, calculated home range sizes, monitored raccoon movement with respect to potential movement barriers, and used resource selection functions …

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Macrophyte Communities Of Lake Winnebago: Baseline Study Of Species Composition With Abundances And Water Quality Conditions, Mackenzie Kessenich May 2012

Macrophyte Communities Of Lake Winnebago: Baseline Study Of Species Composition With Abundances And Water Quality Conditions, Mackenzie Kessenich

Lawrence University Honors Projects

Historical records from Lake Winnebago show minimal macrophyte growth; however, reports from recent years claim that macrophyte growth in some areas of the lake has reached nuisance levels. This study aimed to investigate the species of macrophytes present and their abundances in four near-shore locations, as well as measurements of multiple water quality conditions. Rake sampling was used to identify species and quantify their abundances and distributions. In addition, data were collected on light penetration, Secchi depths, and suspended algae chlorophyll concentrations at each site. These data from shallow near-shore sites reveal trends in changing water clarity and light penetration …

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Effects Of The Manipulation Of Aboveground Plant Diversity In Restoration Management On The Diversity Of Belowground Arthropod Assemblage, Claire E. Gilmore Mar 2012

Effects Of The Manipulation Of Aboveground Plant Diversity In Restoration Management On The Diversity Of Belowground Arthropod Assemblage, Claire E. Gilmore

College of Science and Health Theses and Dissertations

A missing element in restoring belowground soil systems to a relatively healthy state may lie in promoting microarthropod diversity. By contributing to healthy nutrient cycling and assisting in the breakdown of leaf litter a diverse microarthropod population helps improve the overall soil quality. My study evaluated how current restoration practices aimed at maintaining aboveground diversity affects belowground microarthropod populations. I examined how the aboveground manipulation of plant diversity in restoration management practices affects the hyperdiverse assemblage of belowground arthropod communities. Additionally, I examined the relationship between soil nutrient content and microarthropod diversity. This study was conducted within the boundaries of …

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Widespread Triploidy In Western North American Aspen (Populus Tremuloides), Karen E. Mock, Colin M. Callahan, M. Nurul Islam-Faridi, John D. Shaw, Hardeep S. Rai, Stewart C. Sanderson, Carol A. Rowe, Ronald J. Ryel, Michael D. Madritch, Richard S. Gardner, Paul G. Wolf Jan 2012

Widespread Triploidy In Western North American Aspen (Populus Tremuloides), Karen E. Mock, Colin M. Callahan, M. Nurul Islam-Faridi, John D. Shaw, Hardeep S. Rai, Stewart C. Sanderson, Carol A. Rowe, Ronald J. Ryel, Michael D. Madritch, Richard S. Gardner, Paul G. Wolf

Aspen Bibliography

No abstract provided.

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Reflections On Plant And Soil Nematode Ecology: Past, Present And Future, Howard Ferris, Bryan S. Griffiths, Dorota L. Porazinska, Thomas O. Powers, Koon-Hui Wang, Mario Tenuta Jan 2012

Reflections On Plant And Soil Nematode Ecology: Past, Present And Future, Howard Ferris, Bryan S. Griffiths, Dorota L. Porazinska, Thomas O. Powers, Koon-Hui Wang, Mario Tenuta

Department of Plant Pathology: Faculty Publications

The purpose of this review is to highlight key developments in nematode ecology from its beginnings to where it stands today as a discipline within nematology. Emerging areas of research appear to be driven by crop production constraints, environmental health concerns, and advances in technology. In contrast to past ecological studies which mainly focused on management of plant-parasitic nematodes, current studies reflect differential sensitivity of nematode faunae. These differences, identified in both aquatic and terrestrial environments include response to stressors, environmental conditions, and management practices. Methodological advances will continue to influence the role nematodes have in addressing the nature of …

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Reproductive Biology Of Ludwigia Leptocarpa And L. Adscendens Subsp. Diffusa In Ile Ife, Nigeria, Matthew Oziegbe, Julius Olaoye Faluyi Jan 2012

Reproductive Biology Of Ludwigia Leptocarpa And L. Adscendens Subsp. Diffusa In Ile Ife, Nigeria, Matthew Oziegbe, Julius Olaoye Faluyi

Turkish Journal of Botany

Ludwigia L. (Onagraceae) species are known to be invasive in most parts of the world, serving as a threat to native plant species and blocking navigational channels. In Africa, they block waterways and are serious weeds in wet fields, most especially in rice paddies. The floral morphology, mode of sexual reproduction, and mechanism of fruit dispersal in water of L. leptocarpa (Nutt.) H.Hara and L. adscendens (L.) H.Hara subsp. diffusa (Forssk.) P.H.Raven were assessed in the Department of Botany of Obafemi Awolowo University, Ile Ife, Nigeria, from March 2006 to March 2009. L. leptocarpa produced cylindrical, hairy fruits of 34.80 …

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In Vitro Plant Regeneration Via Petiole Callus Of Viola Patrinii And Genetic Fidelity Assessment Using Rapd Markers, Gururaj Chalageri, Uddagiri Venkanna Babu Jan 2012

In Vitro Plant Regeneration Via Petiole Callus Of Viola Patrinii And Genetic Fidelity Assessment Using Rapd Markers, Gururaj Chalageri, Uddagiri Venkanna Babu

Turkish Journal of Botany

Viola patrinii DC. (Violaceae) petiole explants were used for inducing calli. Significant callus proliferation was observed on MS medium supplemented with 16.12 \muM NAA and 13.33 \muM BA. Shoot regeneration was achieved upon transferring the green friable calli to MS medium with a 2-fold dilution of potassium dihydrogen phosphate supplemented with 23.25 \muM Kn and 2.68 \muM NAA. Maximum shoot regeneration was achieved in 4 weeks. Multiple shoots were separated and further cultured in half-strength MS medium supplemented with 9.85 \muM IBA with 2% sucrose. Profuse root development was observed after 20-25 days of culturing. Regenerated plants were successfully transferred …

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Anatomical Analysis Of Red Juniper Leaf (Juniperus Oxycedrus) Taken From Kopaonik Mountain, Serbia, Predrag Spasoje Vasic, Darko Vlajko Dubak Jan 2012

Anatomical Analysis Of Red Juniper Leaf (Juniperus Oxycedrus) Taken From Kopaonik Mountain, Serbia, Predrag Spasoje Vasic, Darko Vlajko Dubak

Turkish Journal of Botany

In this study, the anatomical characteristics of Juniperus oxycedrus (Cupressaceae) leaves from Kopaonik Mountain (Serbia) are analysed. The level of distinction between leaves taken from various altitudes (420-1420 m) was determined by analysing anatomical characters. The clear correlation between increase in altitude and change in anatomical characters of the leaves was not established by descriptive analysis. The leaves collected from plants growing at 620 m had the most prominent xeromorphic characteristics (thick cuticles and thick epidermis walls). The discriminant canonical analysis also showed a clear distinction between red common juniper from 420 m and the samples taken from different altitudes.

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Seasonal Variations In Phytoplankton Communities In Zayandeh-Rood Dam Lake (Isfahan, Iran), Masoumeh Shams, Saeed Afsharzadeh, Tahi̇r Atici Jan 2012

Seasonal Variations In Phytoplankton Communities In Zayandeh-Rood Dam Lake (Isfahan, Iran), Masoumeh Shams, Saeed Afsharzadeh, Tahi̇r Atici

Turkish Journal of Botany

Variations in the phytoplankton of Zayandeh-Rood Dam Lake were studied seasonally from September 2005 to August 2006 at 4 different stations. A total of 112 species and 53 genera belonging to 6 divisions were identified. The species belonging to Bacillariophyta, Chlorophyta, Cyanophyta, Euglenophyta, and Dinophyta were found frequently. Chrysophyta species were found in low numbers. Cyclotella meneghinina Kütz., a centric diatom, was the dominant species at all stations. The density of the phytoplankton was between 470 and 150,470 cells/cm^3. According to the Shannon-Weaver Index, the highest and the lowest diversities were determined in November and May, respectively. Regarding physico-chemical analysis …

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Survey Of The Native And Nonnative Vascular Plant Species Of Three Islands In Lake Winnipesaukee, New Hampshire, Mark Gardner Winkler Jan 2012

Survey Of The Native And Nonnative Vascular Plant Species Of Three Islands In Lake Winnipesaukee, New Hampshire, Mark Gardner Winkler

Electronic Theses and Dissertations

This study examined the long-term patterns in vascular plant composition on three islands in Lake Winnipesaukee, NH. It also tested the role of island biogeography in ecology as it analyzed the effectiveness of a land use plan implemented on the islands. Samplings were made on the islands in the summer of 2011 and were compared to earlier samplings in 1978, 1991, and 2001. The flora was observed and measured in 25 permanent plots that were established on the three islands in 1978. The understory flora was measured by presence and percent cover and the overstory was measured by frequency and …

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The Sign And Strength Of Plant-Soil Feedback For The Invasive Shrub, Lonicera Maackii, Varies In Different Soils, Kelly Schradin, Don Cipollini Jan 2012

The Sign And Strength Of Plant-Soil Feedback For The Invasive Shrub, Lonicera Maackii, Varies In Different Soils, Kelly Schradin, Don Cipollini

Biological Sciences Faculty Publications

Plants alter soil characteristics causing changes in their subsequent growth resulting in positive or negative feedback on both their own fitness and that of other plants. In a greenhouse study, we investigated whether the sign and strength of feedback changed across two distinct soil types, and whether effects were due to shifts in biotic or abiotic soil traits. Using soils from two different locations, we examined growth of the exotic invasive shrub, Lonicera maackii and the related native shrub, Diervilla lonicera, in unconditioned soils and in soils conditioned by previous growth of L. maackii, D. lonicera, and …

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Genetic Structure Of Grass Carp Populations In The Missouri And Mississippi River Basins, Usa, Bobbi M. Adams, Katie N. Bertrand, Michael L. Brown, Donald Auger Dec 2011

Genetic Structure Of Grass Carp Populations In The Missouri And Mississippi River Basins, Usa, Bobbi M. Adams, Katie N. Bertrand, Michael L. Brown, Donald Auger

The Prairie Naturalist

We provided an early characterization of the genetic structure of the grass carp (Ctenopharyngodon idella) population as it expands its distribution in both the Missouri and Mississippi River basins. Further, we provided initial comparisons of allelic richness at 17 polymorphic microsatellite markers between 56 grass carp from the USA, and six from the Yangtze River in China. The number of alleles per locus ranged from two to eight and size ranges of alleles for fish collected from the invaded and native ranges were similar (P ≤ 0.001; 107–226 bp) to those previously reported in the literature. Distance-based clustering …

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Earthworms Of Arkansas And Contributions Of Earthworm Evolutionary Origin And Ecological Group To Nitrogen Cycling In A Model Soil And Tall Fescue System, Peter John Tomlinson Dec 2011

Earthworms Of Arkansas And Contributions Of Earthworm Evolutionary Origin And Ecological Group To Nitrogen Cycling In A Model Soil And Tall Fescue System, Peter John Tomlinson

Graduate Theses and Dissertations

Evolutionary origin and ecological niche may impact how earthworm species affect N cycling. Tall fescue (Lolium arundinaceum (Schreb) S. J. Darbysh) infection with the toxic endophyte Neotyphodium coenophialum Glenn, Bacon & Hanlin (E+) may influence earthworm communities in soil compared to non-toxic endophyte (NE+) infected tall fescue. Conversely, different earthworms may contribute different amounts of N to E+ vs. NE+ tall fescue. A field survey was conducted from January 2007 to January 2008 to determine the impact of E+ and NE+ tall fescue, planting date, and seasonal variables, e.g. soil temperature and moisture, on earthworm species, abundances, and population …

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Bryoecology In The American Southwest: Patterns Of Biodiversity And Responses To Global Change, John Carroll Brinda Dec 2011

Bryoecology In The American Southwest: Patterns Of Biodiversity And Responses To Global Change, John Carroll Brinda

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation combines investigation of the large-scale responses of bryophyte species diversity and distribution with small-scale physiological adaptations to global change. These two areas of inquiry are linked because one way to predict plant species responses to global change is to examine their distribution across current ecological gradients produced by factors such as latitude and elevation. By examining these biogeographic patterns one can identify those species that have a narrow tolerance and therefore are most sensitive to change. Selected bryophytes might then be used as indicator species in long-term monitoring programs. Where historical data exist, these can be used to …

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Msh1 Influence On Plant Mitochondrial Genome Recombination And Phenotype In Tobacco, Peibei Sun Dec 2011

Msh1 Influence On Plant Mitochondrial Genome Recombination And Phenotype In Tobacco, Peibei Sun

School of Biological Sciences: Dissertations, Theses, and Student Research

Plant mitochondrial genomes are composed of unusually complex structures, due to active recombination at numerous repeated sequences in the genome. The maintenance of mitochondrial genome stability is under the control of identifiable nuclear genes. In plants, three nuclear genes (MSH1, RECA3 and OSB1) have been shown to participate in recombination surveillance and the suppression of illegitimate recombination in mitochondria. Disruption of these loci in Arabidopsis results in reproducible mitochondrial genome rearrangements. We demonstrated that repeat-mediated de novo recombination was also enhanced in both Arabidopsis and tobacco during passage through in vitro culture. Furthermore, in vitro conditions led …

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Nitrogen Acquisition By Annual And Perennial Grass Seedlings: Testing The Roles Of Performance And Plasticity To Explain Plant Invasion, A. J. Leffler, T. A. Monaco, J. J. James Oct 2011

Nitrogen Acquisition By Annual And Perennial Grass Seedlings: Testing The Roles Of Performance And Plasticity To Explain Plant Invasion, A. J. Leffler, T. A. Monaco, J. J. James

Natural Resource Management Faculty Publications

Differences in resource acquisition between native and exotic plants is one hypothesis to explain invasive plant success. Mechanisms include greater resource acquisition rates and greater plasticity in resource acquisition by invasive exotic species compared to non-invasive natives. We assess the support for these mechanisms by comparing nitrate acquisition and growth of invasive annual and perennial grass seedlings in western North America. Two invasive exotic grasses (Bromus tectorum and Taeniatherum caput-medusae) and three perennial native and exotic grasses (Pseudoroegneria spicata, Elymus elymoides, and Agropyron cristatum) were grown at various temperatures typical of autumn and springtime when resource are abundant and dominance …

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Temperature Thresholds And Degree-Day Model For Marmara Gulosa (Lepidoptera: Gracillariidae), M. J. O'Neal, David H. Headrick, Gregory H. Montez, E.E. Grafton-Cardwell Aug 2011

Temperature Thresholds And Degree-Day Model For Marmara Gulosa (Lepidoptera: Gracillariidae), M. J. O'Neal, David H. Headrick, Gregory H. Montez, E.E. Grafton-Cardwell

Horticulture and Crop Science

The developmental thresholds for Marmara gulosa Guillen & Davis (Lepidoptera: Gracillariidae) were investigated in the laboratory by using 17, 21, 25, 29, and 33°C. The lowest mortality occurred in cohorts exposed to 25 and 29°C. Other temperatures caused >10% mortality primarily in egg and Þrst and second instar sap-feeding larvae. Linear regression analysis approximated the lower developmental threshold at 12.2°C. High mortality and slow developmental rate at 33°C indicate the upper developmental threshold is near this temperature. The degree-day (DD) model indicated that a generation requires an accumulation of 322 DD for development from egg to adult emergence. Average daily …

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Climate And Vegetation Change In The Newberry Mountains, Southern Clark County, Nevada, Ross Joseph Guida Aug 2011

Climate And Vegetation Change In The Newberry Mountains, Southern Clark County, Nevada, Ross Joseph Guida

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ecological studies have shown worldwide that vegetation is being affected by climate change. Species are shifting to new elevations and physiographic positions to adapt to changes in their environment. More specifically, paleoecology studies in the Mojave Desert have shown shifting vegetation patterns in response to past warming and precipitation changes. Recent studies have shown mortality among desert plants related to extended drought and warming. However, few studies have shown how the geographic distribution of Mojave Desert species has changed during this most recent period of warming. This study addresses this gap in the literature by focusing on several plant species …

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Phragmites Australis In South Dakota: Historical Distribution And Environment, Carol A. Johnston, Kayla L. Miller Jun 2011

Phragmites Australis In South Dakota: Historical Distribution And Environment, Carol A. Johnston, Kayla L. Miller

The Prairie Naturalist

Common reed, Phragmites australis, has long been a component of Northern Plains wetlands, but impending invasion by the non-native P. australis haplotype M may displace native haplotypes in the future. To increase understanding of historical Phragmites occurrence, we developed a geographic information system (GIS) protocol to improve the georeferencing of specimens from South Dakota herbaria, and mapped the distribution of Phragmites relative to geology, physiographic regions, and water bodies. There were 91 Phragmites herbarium specimens from South Dakota and adjacent Wyoming. Phragmites collections occurred in nearly all physiographic regions of the state, with concentrations occurring in the Prairie Coteau of …

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Habitat Selection By Female Swift Foxes (Vulpes Velox) During The Pup- Rearing Season, Indrani Sasmal, Jonathan A. Jenks, Troy W. Grovenburg, Shubham Datta, Greg. M. Schroeder, Robert W. Klaver, Kevin M. Honness Jun 2011

Habitat Selection By Female Swift Foxes (Vulpes Velox) During The Pup- Rearing Season, Indrani Sasmal, Jonathan A. Jenks, Troy W. Grovenburg, Shubham Datta, Greg. M. Schroeder, Robert W. Klaver, Kevin M. Honness

The Prairie Naturalist

The swift fox (Vulpes velox) was historically distributed in western South Dakota including the region surrounding Badlands National Park (BNP). The species declined during the mid-1800s, largely due to habitat loss and poisoning targeted at wolves (Canis lupis) and coyotes (C. latrans). Only a small population of swift foxes near Ardmore, South Dakota persisted. In 2003, an introduction program was initiated at BNP with swift foxes translocated from Colorado and Wyoming. We report on habitat use by female swift foxes during the pup-rearing season (May–July) in 2009. Analyses of location data from 13 radiomarked female foxes indicated disproportional use (P < 0.001) of some habitats relative to their availability within swift fox home ranges. Swift foxes used grassland (ŵ = 1.01), sparse vegetation (ŵ = 1.43) and prairie dog towns (ŵ = 1.18) in proportion to their availability, whereas they were less likely to use woodland (ŵ = 0.00), shrubland (ŵ = 0.14), pasture/agricultural-land (ŵ = 0.25) and development (ŵ = 0.16) relative to availability. Swift foxes typically are located in habitats that provide greater visibility, such as shortgrass prairie and areas with sparse vegetation; which allow detection of approaching coyotes (e.g., primary predator of swift foxes).

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Distribution Of Crayfish Species In Select North Dakota Streams, Cari-Ann Hayer, Terrance L. Velazquez, Mclain S. Johnson, Brian Graeb Jun 2011

Distribution Of Crayfish Species In Select North Dakota Streams, Cari-Ann Hayer, Terrance L. Velazquez, Mclain S. Johnson, Brian Graeb

The Prairie Naturalist

Crayfish have an integral role in aquatic ecosystems, serving as herbivores, predators, detritivores, and prey for fishes and other aquatic and terrestrial animals (Momot 1995, Taylor et al. 1996, Martin 1997). Many crayfish populations are currently declining as a result of habitat alteration (Taylor et al. 1996) and invasive predators (e.g., rusty crayfish Orconectes rusticus [Girard; Lodge et al. 2000]). Knowledge of crayfish distribution and biology in North America and specifically North Dakota is sparse or lacking (Taylor et al. 1996) and baseline information is necessary to identify effects of anthropogenic alterations. Early inventories documented 3 crayfish species in North …

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Summaries Of Arkansas Cotton Research 2010, Derrick M. Oosterhuis May 2011

Summaries Of Arkansas Cotton Research 2010, Derrick M. Oosterhuis

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

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