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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.
81

Virginia Grain Handling Practices and Corn for Poultry Litter Exchange Program

Pelletier, Beth Ann 24 August 1999 (has links)
In the past twenty years the grain industry has experienced production declines in Virginia due to inability to compete with Midwestern grain producers. During this same time, consumption of grain by the poultry industry in Virginia has expanded rapidly. The levels of production and consumption of grain in Virginia are calculated and described on a state, regional, and county basis. Handling, storage, and marketing practices of grain in Virginia are assessed and described. Several different alternatives are presented and evaluated to determine their ability to improve the competitive position of Virginia corn with Midwestern states through the use of poultry litter to decrease production costs and present opportunities for producers to achieve better prices. / Master of Science
82

Design and analysis of static windrow piles for in-house broiler litter composting

Schmidt, Amy M 07 August 2010 (has links)
In-house windrow composting of broiler litter has been studied to reduce microbial populations between flocks. Published time-temperature goals are used to determine the success of the composting process for microbial reductions. Spatial and temporal density of temperature measurement can influence the ability to determine what portion of a windrow pile has achieved specified time-temperature goals. Based on this motivation, an investigation of the heating profile in windrowed litter and the identification of the effects of spatial and temporal sampling densities on the prediction of the heating profile in windrowed broiler litter were executed. Likewise, an investigation of the effects of moisture content on heat generation during composting of broiler litter was conducted. Ultimately, the research projects were designed with the goal of determining the efficacy of windrow composting as a treatment method for reducing microbial populations in broiler litter and to produce recommendations for the implementation of future windrow temperature monitoring investigations. While past investigations have reported success of windrow composting for microbial population reductions, a lack of intense spatial and temporal temperature monitoring has likely mis-represented the pile heating profile and resultant effects on microbial populations.
83

Prevalence of Campylobacter jejuni in newly constructed broiler houses

Eberle, Krista Nicole 07 August 2010 (has links)
Campylobacter is the leading cause of bacterial gastroenteritis in the United States. The objective of this study was to investigate the prevalence of Campylobacter in newly constructed broiler houses and compare three microaerophilic gas delivery methods used to culture Campylobacter in the laboratory. Of 2,300 litter, 900 fecal, and 45 water samples, only 5, 6 and 1 of the samples, respectively, were confirmed positive. style='mso-spacerun:yes'> Results indicated litter moisture content was different across day, location and house. An interaction was detected for litter pH between day, location and flock. Temperatures averaged 26.8°C inside and 27.6°C outside. style='mso-spacerun:yes'> No difference in colony counts were detected among the gas delivery methods. In conclusion, the newly constructed houses showed no significant prevalence of Campylobacter. style='mso-spacerun:yes'> High litter pH, low temperatures, and other onarm management strategies may have suppressed Campylobacter’s ability to colonize the litter. When selecting a gas delivery method price and space should be considered.
84

Factors affecting ammonia volatilization from broiler litter

Miles, Dana McGee 07 August 2010 (has links)
Loss of ammonia from broiler litter degrades air quality, decreases litter fertilizer value, and can have negative health consequences for birds and their caretakers. Rates of NH3 emission from broiler houses are complicated by interrelated management and environmental factors such as air temperature, humidity, house style, ventilation rate,bird age, litter conditions, litter characteristics, and cleanout schedule. Wide variations inemission rates necessitate further investigation of litter characteristics and abatement techniques. The research was designed to clarify the impact of moisture effects that are critical to emissions for poultry litter, in conjunction with bedding type and temperature. Experiments were conducted on litter samples in the laboratory using anacid trap method for determining NH3 losses. Statistical models were developed for predicting release from each bedding material and within the range of litter moistureand temperatures found in commercial broiler houses. This allowed development of relationships that describe the effects of bedding, moisture, time, and temperature on litter generation that have not been published previously. First, type of bedding material was investigated within a limited scope of moisture contents. The results indicated that increasing moisture increases generation from litter. Literature supports the phenomenon that greater litter moisture content up to apoint elicits greater release. At the original moisture content, sand and vermiculite litters generated the most, whereas wood shavings, commercial, and rice hull. Second, an extended range of litter moisture contents (20 – 55%) was investigated while including temperature (18.3 – 40.6 °C) effects. Experiments were conducted using built-up commercial broiler litter from multiple flocks. Response surfaces were parabolic cylinders, indicating maximum production was between 37.4 and 51.5% litter moisture depending on temperature. Comparing the temperature extremes, the maximum up to 7 times greater at 40.6 vs. 18.3 °C. This research defines intermediate critical moisture levels in broiler litter where NH3 is maximized, providing target areasfor researchers and the poultry industry to develop management scenarios to reduce from litter.
85

Accelerated Composting of Hardwood Bark Amended with Organic and Inorganic Fertilizer

Bakhshizadeh, Hoda 15 December 2012 (has links)
The objectives of this study were: 1) To evaluate short-term composting of hardwood bark with combinations of poultry litter and ammonium nitrate and 2) To determine the suitability of composted material for ornamental plant media. In a 3-month accelerated composting study, hardwood bark was amended with (20% & 40%) poultry litter, (1% & 2%) ammonium nitrate, or unamended. Composting was run in fifteen 35- gallon containers and samples were collected at day 0, 45, and 90 for pH, moisture content, carbon-to-nitrogen ratio, compost maturity, toxicity, and green house evaluations. The amendment containing 40% poultry litter showed significantly higher weight reduction than others at days 45 and 90. Also, this treatment showed significantly higher mass weight in transplanted zinnia and gardenia than other treatments and was comparable to commercial media. Overall, results indicated that the amendment of hardwood bark with poultry litter could produce comparable product to currently used commercial container media.
86

The Use of Summer Cover Crops and Composted Broiler Litter in Fall Organic Vegetable Production

Reynolds, Sarah M 11 May 2013 (has links)
Cover crops and composted broiler litter (CBL) are two organic methods used to improve soils and organic vegetable production. The objectives of this study included determining the extent summer cover crops and CBL alter nutrient availability in soil, determining how summer cover crops and CBL influence fall vegetable crops in organic production systems and identifying which cover crops/ CBL combinations improve fall vegetable crop production best. Four cover crops were tested: sunn hemp (Crotalaria juncea), sesame (Sesamum indicum), sorghum sudan grass (Sorghum X drummondii) and a sunn hemp + sesame blend, in combination with four composted broiler litter rates: 0, 2,800, 5,600, 11,200 kg.ha-1 for two years. Few differences were seen among cover crop treatments except for the sorghum sudan grass treatment, which had negative effects on fall broccoli production unless combined with CBL. The CBL increased nutrient availability, percent organic matter, pH and broccoli yield as the rate increased.
87

A multivariate analysis of tree species influence on forest floor fertility /

Pelletier, Bernard, 1964- January 1993 (has links)
No description available.
88

Effects of base cation fertilization on litter decomposition in a sugar maple forest

Lukumbuzya, T. K. (Tadde Kahana) January 1993 (has links)
No description available.
89

Variation in nutrient dynamics among full-sib families of Picea mariana (Mill.) B.S.P. at two sites differing in water availability

Stoklas, Ulrica F. January 1997 (has links)
No description available.
90

Effects of Disturbance History on Forest Soil Characteristics in the Southern Appalachian Mountains

Jones, Michael David 02 October 2000 (has links)
Minimally disturbed virgin forest soils in the Little Santeetlah Creek (LSC) watershed of western North Carolina were sampled along with soils from the adjacent disturbed Slickrock Creek (SRC) watershed. Soils with similar elevation/landform/vegetation/parent material characteristics were initially sampled at nine random locations each on north and south aspects within each watershed with a soil push probe. Some differences in parent materials were noted on south aspects (metasandstone vs. phyllite), but parent materials under north aspect soils were identical (metasandstone). Soils in LSC were significantly deeper and relatively free of solum coarse fragments while SRC soils were shallower and higher in coarse fragments. Subsequent auger observations of three typical pedons on each aspect indicated that soils in LSC were well-developed with gradual horizon boundaries and common diffuse transition horizons, while soils in SRC were more compact in horizonation and lacked diffuse transitional horizons. Vegetation communities were similar across both watersheds, except that SRC south sites were higher in Pinus spp. Litter layer morphology differed strongly between the two watersheds. Specifically, well-developed humus (H) layers were typical in LSC, but completely absent in all typical pedons described in SRC. Data obtained from these two watersheds indicate strong differences in surface soil (O + A horizon) properties between the two. These observed differences could be due to differential anthropogenic effects, particularly logging and associated erosion in the early 1920's. However, further study over multiple disturbed watersheds in the region, and of the distribution of sediments and colluvium within them would be required to test this hypothesis. / Master of Science

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