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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

How Does An Invasive Ant, <i>Nylanderia fulva</i>, Affect Prairies?

Reihart, Ryan William 09 August 2021 (has links)
No description available.
52

Assessing Gene Flow in Switchgrass (<i>Panicum virgatum</i>) and <i>Miscanthus</i> spp.:Implications for Bioenergy Crops

Chang, Hsiaochi 16 September 2015 (has links)
No description available.
53

MODELING THE POTENTIAL FOR GREATER PRAIRIE-CHICKEN AND FRANKLIN’S GROUND SQUIRREL REINTRODUCTION TO AN INDIANA TALLGRASS PRAIRIE

Zachary T Finn (11715284) 22 November 2021 (has links)
<p>Greater prairie-chickens (<i>Tympanuchus cupido pinnatus</i>; GPC) have declined throughout large areas in the eastern portion of their range. I used species distribution modeling to predict most appropriate areas of translocation of GPC in and around Kankakee Sands, a tallgrass prairie in northwest Indiana, USA. I used MaxEnt for modelling the predictions based on relevant environmental predictors along with occurrence points of 54 known lek sites. I created four models inspired by Hovick et al. (2015): Universal, Environmental, Anthropogenic-Landcover, and Anthropogenic-MODIS. The Universal, Environmental, and Anthropogenic-MODIS models possessed passable AUC scores with low omission error rates. However, only the Universal model performed better than the null model according to binomial testing. I created maps of all models with passing AUC scores along with an overlay map displaying the highest predictions across all passing models. MaxEnt predicted high relative likelihoods of occurrence for the entirety of Kankakee Sands and many areas in the nearby landscape, including the surrounding agricultural matrix. With implementation of some management suggestions and potential cooperation with local farmers, GPC translocation to the area appears plausible.</p> <p>Franklin’s ground squirrels (<i>Poliocitellus franklinii</i>; FGS) have declined throughout a large portion of the eastern periphery of their range. Because of this, The Nature Conservancy is interested in establishing a new population of these animals via translocation. The area of interest is tallgrass prairie in northwest Indiana, USA: Kankakee Sands and the surrounding landscape. Species distribution modelling can help identify areas that are suitable for translocation. I used MaxEnt, relevant environmental variables, and 44 known occurrence points to model the potential for translocation of FGS to Kankakee Sands and the surrounding area. I created four models inspired by Hovick et al. (2015): Universal, Environmental, Anthropogenic-Landcover, and Anthropogenic-MODIS. I created maps of models with passing AUC scores. The final map was an overlay map displaying the highest relative likelihood of occurrence predictions for the area in all passing models. Only the Universal and Anthropogenic-MODIS models had passable AUC scores. Both had acceptable omission error rates. However, none of the models performed better than the null model (p < 0.05). MaxEnt predicted that a few areas in and outside of Kankakee Sands possess high relative likelihoods of occurrence of FGS in both the Universal and Anthropogenic-MODIS models. However, MaxEnt predicted high relative likelihoods in the surrounding agricultural matrix in the Universal Model. FGS prefer to cross through agricultural areas via unmowed roadside instead of open fields (Duggan et al. 2011). Because of this, high predictions in agricultural matrices in the Universal model are irrelevant. High relative likelihood predictions for linear sections that are obviously roads are disregardable in the context of my modeling efforts. Because of my low sample size, none of the models are really reliable in predicting relative likelihoods of occurrence for this area. Despite high relative likelihood predictions, the appropriateness of a translocation effort to the area is inconclusive.</p>
54

Revision of the Subgenus Prionus (Neopolyarthron) Semenov (Coleoptera: Cerambycidae: Prioninae) in North America, with Notes on Prionus (Antennalia) Casey

Schiefer, Terence L 14 December 2018 (has links) (PDF)
The classification of North American species of Prionus (Prionus) Geoffroy is reevaluated, with three subgenera recognized: P. (Antennalia) Casey, revived status, P. (Neopolyarthron) Semenov, revived status, and P. (Prionus). Prionus (Neopolyarthron) is revised and consists of P. imbricornis (Linnaeus), P. debilis Casey, revived status, and P. cuneatus Casey, revived status, with the latter two species removed from synonymy with P. imbricornis. Prionus robustus Casey, new synonymy, and P. fissicornis parviceps Casey, revised synonymy, are transferred from synonymy with P. imbricornis to synonymy with P. cuneatus and P. fissicornis respectively. Keys to North American subgenera of Prionus and to species of P. (Neopolyarthron) are provided. Species of P. (Neopolyarthron) are redescribed, diagnosed, and illustrated, and the distribution, hosts, habitat, and conservation status of each are discussed. Species distribution maps are provided, along with 26 new state records. Prionus fissicornis is diagnosed, and type specimens of its synonyms are reviewed and illustrated.
55

Effects of white-tailed deer herbivory on a tallgrass prairie remnant

Gooch, Scott 11 January 2010 (has links)
A study was conducted to determine what impact high white-tailed deer (Odocoileus virginianus) densities were having on the native grasslands of a tallgrass: aspen forest tract embedded within an agro-urban setting. Due to excessive spring moisture, row-crops were unavailable the first year. Using microhistological fecal analysis to determine dietary composition, deer were assessed to be placing the site’s favoured native plant species at risk of extirpation. Measuring woody stem abundance and height along and near the prairie: forest ecotone, deer were found to restructure woody growth but not directly influence encroachment rates. Indirectly, however, deer facilitated forest encroachment and prairie degradation through seed dispersal, nitrogen deposition, gap-dynamics, and trampling. Comparing dietary composition to nutritional data, deer grazed to maximize fitness, selecting foods high in IVDMD, minimizing energy expenditure, and optimizing CP. High crop CP was offset by intensively grazing particular native plants. ADF was an effective nutritional marker, not AIA.
56

Effects of white-tailed deer herbivory on a tallgrass prairie remnant

Gooch, Scott 11 January 2010 (has links)
A study was conducted to determine what impact high white-tailed deer (Odocoileus virginianus) densities were having on the native grasslands of a tallgrass: aspen forest tract embedded within an agro-urban setting. Due to excessive spring moisture, row-crops were unavailable the first year. Using microhistological fecal analysis to determine dietary composition, deer were assessed to be placing the site’s favoured native plant species at risk of extirpation. Measuring woody stem abundance and height along and near the prairie: forest ecotone, deer were found to restructure woody growth but not directly influence encroachment rates. Indirectly, however, deer facilitated forest encroachment and prairie degradation through seed dispersal, nitrogen deposition, gap-dynamics, and trampling. Comparing dietary composition to nutritional data, deer grazed to maximize fitness, selecting foods high in IVDMD, minimizing energy expenditure, and optimizing CP. High crop CP was offset by intensively grazing particular native plants. ADF was an effective nutritional marker, not AIA.

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