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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.
61

Understand Willingness to Pay for Pollination and User Sense of Place Connections on the Eastern Shore

Johnson, Wesley James 02 November 2017 (has links)
The global decline of pollinators, insects and animals that assist in pollination and fertilizing plants, poses a great risk to global food supply. This study investigates if people have preferences for a program to abate decline in a region along the East Coast of the United States. A survey is used to investigate these preferences and connections to the region to understand if individual connections can explain preferences. The majority of people were found to not have preferences to help increase pollinator abundance. Additionally, measures of connection to the region were found to be insignificant in explain individual preferences. / Master of Science
62

Sericea lespedeza (Lespedeza cuneata): seed dispersal, monitoring, and effect on species richness

Blocksome, Carolyn E. January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / Walter H. Fick / Sericea lespedeza [Lespedeza cuneata (Dumont) G. Don] is a rangeland weed of the tallgrass prairie of Kansas. Experiments were carried out during the 2001-2003 growing seasons (June-November) to examine the relationship between sericea lespedeza and other rangeland species, wildlife use and dispersal of sericea lespedeza propagules, and the relationship between sericea lespedeza stubble height and utilization by livestock. Sericea lespedeza cover was positively correlated with violet lespedeza (r=0.25) [Lespedeza violacea (L.) Pers.], heath aster (Aster ericoides L.) (r=0.23) and total forb cover (r=0.56). Sericea lespedeza composition was negatively correlated with big bluestem (Andropogon gerardii Vitman.) (r=-0.27) and sideoats grama [Bouteloua curtipendula (Michx. Torr.)] (r=-0.27) composition and positively correlated with western ragweed (Ambrosia psilostachya D.C.) (r=0.21) and violet lespedeza (r=0.36) composition. Sericea lespedeza density was inversely related to forb species richness on all sites. On half the sites, there was also an inverse relationship between grass species richness and sericea lespedeza density. Grazed sites had less difference in grass species richness between high and low levels of sericea lespedeza densities. There was no evidence of an ecological threshold to the detriment of species richness with increasing sericea lespedeza density. Cattle digestive processes did not affect sericea lespedeza germination. Quail digestive processes enhanced germination of the few seeds that were excreted. Quail diet selection was investigated with a field study. Five out of 49 crops collected contained seed classified as sericea lespedeza. None of these seeds germinated in the greenhouse. Both cattle and quail could potentially disperse sericea lespedeza seed, but voluntary consumption appears to be low for both species, at least during November when other food is available. An height-weight table estimating percent utilization for various grazed and ungrazed heights of sericea lespedeza was constructed. Coefficient of determination values were greater than 0.85 between plant height and weight, indicating that the heightweight method was appropriate for estimating sericea lespedeza utilization. Using additional regression analysis, a chart for estimating forage from percent of plants grazed was constructed.
63

Quantifying the economic impact of conservation policy changes utilizing precision agriculture tools

Watkins, Kyle Stanley 13 May 2022 (has links) (PDF)
The United States Farm Bill is a multi-billion-dollar federal legislation reenacted every five years to provide funding towards crop protection, nutrition, environmental protection, and other important focuses. The largest conservation program within the Farm Bill is the Conservation Reserve Program, which encompasses many conservation practices such as CP-33: habitat buffers for upland birds. Conservation implementation through the Farm Bill relies on voluntary producer enrollment in exchange for a rental fee to not farm enrolled land for a set time. I used yield data collected across six years from 36 agricultural fields in Humphreys and Holmes counties, Mississippi, USA, and a range of commodity prices to compare the change in economic and environmental opportunities available through economically targeted conservation enrollment between the 2014 Farm Bill and the 2018 Farm Bill. I found the 2014 Farm Bill was consistently higher in economic revenue and conservation opportunity compared to the 2018 Farm Bill
64

Integrated Population Modeling of Northern Bobwhite and Co-occupancy with Open-land-Dependent Birds in Southern Ohio

Rosenblatt, Connor James January 2020 (has links)
No description available.
65

Survival and Habitat Use of Non-breeding Northern Bobwhites on Private Lands in Ohio

Janke, Adam K. 16 December 2011 (has links)
No description available.
66

Immunomodulation by dietary lipids: soybean oil, menhaden fish oil, chicken fat, and hydrogenated soybean oil in Japanese quail (Coturnix coturnix japonica) and Bobwhite quail (Colinus virginianus)

Weng, Bor-Chun Brian 21 August 2002 (has links)
Soybean oil (SBO), menhaden fish oil (FO), chicken fat (CF) or hydrogenated soybean oil (HSBO) were incorporated at 5% of the total diet to study changes in the immunological status of both Japanese quail (JAP) and Bobwhite quail (BOB). The SBO diet, in which 66% of the total fatty acids were polyunsaturated fatty acids (PUFA), was rich in linoleic acid (LA 18:2 n-6), alpha-linolenic acid (ALA 18:3 n-3) and low in saturated fatty acid (SFA). The FO diet which contained about 50% PUFA, had only 40% n-6 fatty acids and 8% n-3 PUFA. The trans fatty acid isomers and other monounsaturated fatty acids (MUFA) were high in the HSBO diet. The diet containing CF provided a relatively balanced fatty acid composition with 18% SFA, 31% MUFA and 50% PUFA. Plasma fatty acid and hepatic fatty acid profiles consistently reflected their respective dietary lipid treatments. There were no differences in the fatty acid profile between blood and liver within respective dietary treatments in the two species. Dietary fatty acids had no effect on antibody titers against sheep red blood cells (SRBC) at 1, 2 and 8 months following the start of dietary lipid treatment in JAP. However, female JAP fed FO had a significantly (p< 0.05) higher antibody production compared to the other dietary lipid treatments at 4 months following the start of fatty acids supplementation. BOB fed either FO or SBO diets had a higher immunoglobulin G production compared to birds fed the CF diet. The total antibody titer was significantly higher in BOB fed SBO compared to CF. Dietary fatty acids had a significant effect on cell-mediated immunity (CMI) as accessed by toe web thickness 24 hours post intradermal injection of phytohemagglutinin-P (PHA) in both JAP and BOB. In general, birds fed a FO diet had a significantly higher CMI response than those fed HSBO. A diet high in n-3 PUFA increased the index of cutaneous basophil hypersensitivity (CBH), while the high trans fatty acid isomers suppressed the CBH response. By observing a CBH response over a 72-hour period in JAP, it was concluded that quail fed CF or SBO had a different peak response time (12 hours post PHA challenge) and amplitude compared with those fed FO or HSBO (24 hours post PHA challenge). Phagocytic ability was not affected by dietary lipid treatments in BOB while the quail fed FO diet had a faster carbon clearance rate. The FO fed JAP had a significantly higher response (p< 0.05) to concanavalin A ensiformis (CONA) compared to HSBO fed birds. There was no difference in B lymphocyte proliferation stimulated by lipopolysacchride (LPS) in female JAP, whereas it was significantly higher in male JAP fed SBO compared to those fed FO and HSBO. Phorbol 12-myristate 13-acetate/ionomycin calcium salt (PMA/ION) was used to nonspecifically stimulate cell proliferation by increasing chromosome mitosis. Dietary FO or HSBO suppressed cell proliferation stimulated by PMA/ION. However, JAP fed SBO or CF had a significantly higher PMA/ION stimulated lymphocyte proliferation compared those fed FO or HSBO. In male BOB, the FO fed birds had the highest response to all mitogens. In contrast, female BOB did not show any dietary effects by lymphocyte proliferation. Consistent with JAP, BOB fed HSBO had depressed lymphocytes proliferation in response to various mitogens stimulation. In general, female birds had a higher plasma total protein (PTP) and lower pack cell volume (PCV) compared to their males counterparts in both BOB and JAP. In summary, in in vivo experiments, feeding a diet high in menhaden fish oil that is rich in n-3 PUFA enhanced the CMI. There was a minimal effect on antibody production caused by feeding n-3 PUFA in JAP since a significant treatment effect was only found at one sampling period, while BOB were more sensitive to dietary lipid manipulation and had a higher antibody production with SBO or FO treatments. Dietary lipids exerted different effects in the two species in in vitro experiments. While both BOB and JAP fed FO had higher lymphocyte proliferation to CON A mitogen compared to those fed HSBO, only male BOB showed a higher proliferation to LPS. Feeding HSBO that contained a higher content of trans fatty acid isomers, MUFA, but lower PUFA content resulted in the lowest lymphocyte proliferation to various mitogens in both BOB and JAP. / Ph. D.
67

Effects of Five Different Intensities of Stand Establishment on Wildlife Habitat Quality and Tree Growth in Loblolly Pine (Pinus Taeda) Plantations in Southern Mississippi

Jones, Phillip Daniel 03 May 2008 (has links)
I evaluated effects of 5 intensive pine plantation establishment regimes during years 1 – 5 post-establishment on vegetation communities, loblolly pine (Pinus taeda) growth, nutritional carrying capacity for white-tailed deer (Odocoileus virginianus), habitat values for northern bobwhite (Colinus virginianus), and projected financial viability in the Lower Coastal Plain of Mississippi. Treatments were combinations of mechanical site preparation (MSP), chemical site preparation (CSP), and herbaceous weed control (HWC) designed to reflect the range of operational intensities on industrial forest lands in the southeastern U.S. Results should inform plantation management decisions throughout the region. Pine growth increased with greater treatment intensity. At age 5, trees in the most intensively managed treatment were 1.5 m taller than those in the least intensive treatment. Mechanical site preparation improved growth by alleviating soil physical problems. Growth and yield projections indicated that increased fiber yield may not justify investment in more intensive regimes; financial analysis favored the least expensive treatment, though all regimes produced potential internal rates of return > 9% when managed to financial maturity. Use of MSP with banded HWC yielded abundant low-quality deer forage sufficient for body maintenance; nutritional needs for lactating does were better served by CSP with banded HWC. Broadcast HWC reduced biomass of high-quality forbs. In this region of limited soil nutrients and abundant low-quality forages, the optimal combination of maintenance-level and lactation-level nutrition was provided by CSP or CSP and MSP combined with banded HWC. I evaluated vegetation communities for nesting, loafing, brood-rearing, and fall and winter food suitability for northern bobwhite. No treatment provided brood-rearing habitat due to combined lack of bare ground and forb coverage. Fall and winter feeding, nesting, and loafing cover were best produced by MSP and CSP combined with banded HWC. However, lack of brood-rearing cover may reduce or eliminate usable space in all treatments. Differences between vegetation communities were caused by use of CSP, which eliminated many residual woody and vine species, and by differences in broadcast versus banded HWC. Herbicide use decreased plant diversity and species richness, and impacted successional trajectory. Community differences persisted through year 5.
68

Spring Dispersal and Breeding Ecology of Northern Bobwhite in Southwest Ohio

Liberati, Marjorie R. 20 May 2013 (has links)
No description available.
69

Survival and Covey Density of Northern Bobwhites in Relation to Habitat Characteristics and Usable Space in Ohio

Knapik, Randall T. 13 August 2015 (has links)
No description available.
70

Vegetation Response and Use of Wooded Edges by Northern Bobwhites After Edge-Feathering Treatment in Southwestern Ohio

Brooks, Coree Adam 20 August 2015 (has links)
No description available.

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