• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 17
  • 4
  • 3
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 30
  • 30
  • 7
  • 5
  • 5
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • 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.
1

Poultry manure as a feed ingredient for livestock : ruminants and non-ruminants

Kobets, Mary Frances, Sister January 2010 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
2

Dehydrated poultry waste : influence on broiler growth, flavor, and composition

Lillich, Gary Allen January 2011 (has links)
Digitized by Kansas Correctional Industries
3

The effects of poultry manure versus inorganic fertilizer use on copper, manganese and zinc concentrations on soils under raspberry cultivation

Wolterson, Eveline Valerie January 1989 (has links)
The effects of poultry manure versus inorganic fertilizer use on copper, zinc and manganese concentrations and the sustainability of metal contents under raspberry cultivation was investigated on two aeolian soils in the Lower Fraser Valley, British Columbia. Total elemental analysis by a teflon bomb procedure using reverse aqua regia and hydrofluoric acid was done on soils sampled at three depths (0-15 cm, 15-30 cm and +40 cm) and results were compared to metal contents extracted by the Mehlich III method. High variability of some of the soil data was attributed to mixing of the loess capping with the underlying glacio-fluvial outwash material, differences in site conditions of the test fields, variations in sampling depth, and inadequate analytical reproducibility at the low concentrations found in some of the soils. For the variables tested, differences between sites most often occurred in the first 30 cm and never at the +40 cm depth. Higher contents in the 0-30 cm depth than in the lower depths indicated an enrichment of the surface layers either by anthropogenic inputs or by bioaccumulation. Poultry manure applications had a significant effect on organic matter content, total and available manganese, and total and available zinc in both soils studied. The comparison of the manured versus the inorganically fertilized site indicated that zinc was the metal most effected by the manure application. The other metals were not significantly increased by poultry manure amendments. The comparison of the site that had been under long-term raspberry cultivation against the site that had been only recently converted to raspberries from long-term pasture cover, showed that long-term raspberry cultivation reduced metal and organic matter contents in the 0-15 cm depth and increased these variables in the 15-30 cm depth. It was hypothesised that this was in direct response to differing biocycling patterns under different land uses. Total and available manganese and zinc were strongly interconnected and their correlation to the organic matter content appeared most interesting in terms of fluxes between the various soil components. inorganically fertilized site indicated that zinc was the metal most effected by the manure application. The other metals were not significantly increased by poultry manure amendments. The comparison of the site that had been under long-term raspberry cultivation against the site that had been only recently converted to raspberries from long-term pasture cover, showed that long-term raspberry cultivation reduced metal and organic matter contents in the 0-15 cm depth and increased these variables in the 15-30 cm depth. It was hypothesised that this was in direct response to differing biocycling patterns under different land uses. Total and available manganese and zinc were strongly interconnected and their correlation to the organic matter content appeared most interesting in terms of fluxes between the various soil components. / Land and Food Systems, Faculty of / Graduate
4

Implications of livestock feeding management for soil fertility in smallholder mixed farming systems

Delve, Robert James January 1998 (has links)
No description available.
5

Treatment of Ammonia in Air Streams by Biotrickling Filters

Wang, Chia-Hsi 17 July 2000 (has links)
Abstract Ammonia is a major odoriferous component in the vent gas of the fermentation process of poultry manure compost. To prevent environmental problems, it is full-scale and a lab-scale biotrickling filters (BTF) were used for treatment of ammonia in air streams. The full-scale BTF was constructed by reinforced concrete (inner size = 6 m square ¡Ñ 5 m height) with PVC plate packings (total volume =6 m square ¡Ñ 3 m height = 108 m3 , specific area = 100 m2/m3). Long-term (357 days) experimental results show that, in the conditions of gas empty-bed-retention time EBRT = 35-77 s, liquid-gas ratio L/G = 5-11 L/m3, and recirculation liquid pH = 6.5-6.8, 6.5-29.8 ppm (average 14.3 ppm) ammonia in the influent gas could be reduced to 0-2.0 ppm (average 0.66 ppm). Daily rates were supplementary water = 0.400 m3, discharge water = 0.360 m3, supplementary H3PO4 (85%) = 0.28 kg. With the average volumetric ammonia loading of 0.66 g NH3-N/m3h, the system could achieve an average nitrification efficiency of 62% without supplementary glucose. Ammonia removal efficiencies of over 90% were obtained with recirculation liquid pH¡Ø6.8, and below 22% with pH¡Ù7.33. The lab-scale BTF consisted of a set of two-stage-in-series biotrickling filters, an influent gas supply system, and a liquid recirculation system. Each stage of the biotrickling filter was constructed from a 20 cm ¡Ñ 200 cm (inside diameter ¡Ñ height) acrylic column packed with cokes (average diameter = 3.0 cm and specific area = 150 m2/m3) of 125 cm height. Experimental results indicate that a time of 30 days was required for development of biofilms for nitrification of the absorbed ammonia from the gas. Long-term (187 days) experimental results show that, in the conditions of EBRT = 7.25 s, L/G=7.7 L/m3, and liquid pH=6.65, 230 ppm ammonia in the influent gas could be reduced to 4.0 ppm. With the volumetric ammonia loading of less than 7.37 g NH3-N/m3h, the system could achieve ammonia removal and nitrification efficiencies of 98 and 94%, respectively, without supplementary glucose. However, with a loading of 13.1 g NH3-N/m3h, both decreased gradually due to a lake of carbon (glucose) source and an accumulation of nitrite and nitrate in the recirculation liquid.
6

Uptake, leaching, and storage of micronutrient metals in response to heavy applications of poultry manure

Safo, Ebenezer Yeboah January 1978 (has links)
The partitioning among plant uptake, leaching from and storage in soil of micronutrient metals following heavy applications of poultry manure was studied in three greenhouse experiments. Following these experiments, the study examined the effect of manure application on content and composition of soil organic matter and also the distribution of metals in the organic fractions. Poultry manure was surface-applied to Grigg and Monroe silt loam soil columns at rates of 0, 20 and 40 t/ha in each of the first two experiments, whereas the third tested the residual effect of the manure applications. Treatments were replicated four times and completely randomized. The soil columns were planted to corn (Zea mays L.) and leached daily with demineralized water at an average rate of 1.0 cm/day for 30-40 days. Following leaching and harvest of the corn, the soil columns were sampled in two sections for chemical analysis. Metals in the soils, leachates and corn tissue were determined by atomic absorption spectrophotometry. Manure application significantly (P < 0.01) influenced corn yield in Experiments I and II. The 20 t/ha rate increased yield more than the 40 t/ha treatment. Yield increases over the check treatment in Experiment I were about 400% and 300% from the 20 and 40 t/ha treatments respectively. In Experiment II, yield response was significantly curvilinear (P < 0.01), with the 20t rate giving the highest yield. The possibility of NH₃ toxicity and excess soluble salt injury resulting from the 40 t/ha rate was suggested. In Experiment III yield increases over the check treatment were about 300% and 500% from the 20 and 40 t/ha previous rates respectively. The study found no evidence for significant uptake or leaching of the toxic heavy metals (Cd, Cr, or Pb), such as is usually encountered with sewage sludge application. In Experiments I and II, total uptake of Mn, Fe, Zn, and Cu increased with the application of 20 t/ha and then decreased with the 40 t rate. In Experiment III, previous manure applications led to increases in uptake of these metals. The concentration of these metals in corn tissue decreased with the application of 20 t/ha and then increased with the 40 t rate in Experiment I. However, In both Experiments II and III the tissue metal concentration decreased with manure application. These effects were attributed largely to changes in yield. However, in no case did changes in concentration of metals exceed suggested tolerance limits. These results suggested that relatively high rates of poultry manure may be applied to the soil without appreciable danger of developing conditions of micronutrient metal toxicities. High manure rates led to increased leaching losses of K and Na. However, leaching losses of Mn, Fe, Zn, and Cu decreased with the application of 20 t/ha and then increased with the 40 t rate. Assuming independent contributions of metals from various potential sources, ratios of uptake and leaching losses to the input sources were examined. Both uptake and leaching losses of metals were small in magnitude in comparison with initial soil total levels and manure input. Despite the varied patterns of uptake and leaching losses of metals in response to the manure application, their storage in soil increased with rates of application. There was no consistent pattern in the distribution of metals in the top and lower halves of the soil columns after Experiments I and II. Examination of the distribution of organic fractions and associated metals following the greenhouse experiments indicated that soil organic matter content increased with manure application. The humic acid fraction made up 69 to 75% and the fulvic fraction 25 to 31% of the soil extractable organic matter. Despite such a high proportion of organic matter in the humic fraction, the data indicate that a greater proportion of metals in the organic fraction was associated with the fulvic fraction. / Land and Food Systems, Faculty of / Graduate
7

The recovery and behavior of fertilizer nutrients from the anaerobic digestion of poultry manure

Field, James Aaron January 1983 (has links)
Nutrients of animal manures digested anaerobically for biogas production are highly conserved. The objectives of this study are to evaluate changes in the fertilizer value of poultry manure following digestion. Total kjeldahl N (TKN) was completely recovered during digestion, however, NH₄⁺N was 159 and 151% recovered fran pilot scale plug flow and laboratory scale digesters. This indicates that added organic N is mineralized. Recovered N and K were associated with liquid fractions and P, Ca, Mg and micronutrients were associated with solids of digested slurries. The mineralization of organic N fran soil applied effluent was 2.3 times greater in comparison to influent over a 33.5 week laboratory incubation period. Higher mineralization is due to segregation of decay resistant solids into the settled sludge and the decrease in surface area of suspended solids during digestion. Significantly higher NH₃N volatilization (3 fold to 62%) of land applied effluent compared to influent is due to increases in pH and NH₄⁺N:TKN during digestions. Yields of corn (Zea mays L.) grain at two sites were similar for effluent, influent and urea treatments receiving identical N rates. However, the silage yield of the urea treatment was significantly 19.9% higher than that of the effluent at site 1. Yields and ear leaf N were highly correlated with applied N discounted for NH₃N losses. This indicates that organic N of the effluent and influent become plant available during the growing season. / M.S.
8

The economic potential of establishing a poultry litter handling industry

Napit, Krishna Bahadur 08 August 2007 (has links)
Rapid increases in poultry litter production in concentrated areas has caused litter to be overapplied to nearby cropland at higher rates than the agronomic requirements of crops. Surface and ground water pollution has resulted due to leaching and runoff of nutrients in the litter. One solution to this litter disposal problem is to move litter from areas of concentrated poultry production (litter-surplus areas) to adjoining areas that have the capacity to absorb more litter for fertilizer and animal feed (litter-deficit areas). A linear programming feed cost minimization model was used to estimate the value of litter as a feed for beef stockers and beef cows. The value of litter in beef and stocker rations were estimated by determining the value of alternative feeds replaced by litter. The value of litter for use as fertilizer was estimated by determining the value of commercial fertilizer replaced by litter in selected crop rotations. The services and costs required to make litter available for fertilizer and feed were estimated. A linear programming cost minimization model was used to estimate the costs of moving varying amounts of litter from surplus to deficit counties in Virginia for use as fertilizer. Results indicated that it is economically feasible to establish a poultry litter handling industry. Results indicated more profit potential in moving litter for fertilizer than for feed. The profit potential to a litter handling firm is affected by several factors including the price of commercial fertilizer, waste management requirements, and litter storage subsidies. In order to increase the use of poultry litter for use as fertilizer and feed, it is necessary to educate farmers and the public about the nutritive and economic value of litter as a fertilizer and animal feed. / Ph. D.
9

Mineralisation and bioavailability of phosphorus from poultry manure and sewage sludge-based phospho-composts for maize production

Chauke, Rhandu January 2014 (has links)
Thesis (MSc. Agriculture (Soil Science)) -- University of Limpopo, 2014 / Phospho-composts of different mix ratios (5:5, 7:3, 8:2 and 9:1) were produced through thermophilic co-composting of poultry manure (PM) and sewage sludge (SS) with ground phosphate rock (GPR). Composted PM and SS without GPR addition were included as control. Cured phospho-composts were chemically characterised and used for both laboratory incubation and greenhouse studies, respectively for phosphorus (P) mineralisation and bioavailability, over a period of 42 days. Results revealed that Bray-P1 concentration measured in compost amended soils at 14, 21 and 42 DAI differed significantly (P<0.05) and ranged between 5.47 and 11.14 mg kg-1 and between 5.28 and 11.78 mg kg-1 in poultry manure and sewage sludge-based phospho-composts, respectively. The maximum amount of cumulative P mineralised of 16.06 and 9.98 mg kg -1, respectively in PM and SS-based phospho-composts were obtained from the 8:2 mix ratio. The content of the acid detergent fibre of the different phospho-composts showed positive and significant correlation with cellulose, lignin and total organic carbon (TOC). Similarly, cellulose as well as C:P ratio showed significant correlation with both lignin and TOC. The polynomial relationship between cumulative P mineralised and the various GRP and manure mix ratios revealed significant and positive R2- values of 0.731 and 0.613 for PM and SS-based phospho-composts, respectively. The maximum amount of maize tissue P uptake of 0.12 and 0.11 mg pot-1 in PM and SS-based phospho-compost respectively were also obtained from the 8:2 mix ratio while the least amount of 0.04 mg P pot-1 was obtained from GPR and unamended pots. Maize tissue P uptake following the phospho-compost application was significantly affected by the differences in soil type. Tissue P uptake was 0.06 and 0.11 mg P/pot, respectively in low potential and high potential soils with a significantly higher value. The use of the different phospho-composts showed great potential for amelioration of P-deficiency problems in crops while thermophilic cocomposting improved the solubility and bioavailability of P from non-reactive GPR. Keywords: Ground phosphate rock; poultry manure; sewage sludge; phosphocomposts; phosphorus mineralisation; soil fertility management.
10

Preventive control of ammonia and odor emissions during the active phase of poultry manure composting

Zhang, Wenxiu 05 1900 (has links)
Traditional measures used in the composting industry for ammonia and odor emissions control are those involving collection and treatment such as thermal oxidation, adsorption, wet scrubbing and biofiltration. However, these methods do not address the source of the odor generation problem. The primary objective of this thesis research was to develop preventive means to minimize ammonia and odor emissions, and maximize nitrogen conservation to increase the agronomic value of compost. Laboratory-scale experiments were performed to examine the effectiveness of various technologies to minimize these emissions during the active phase of composting. These techniques included precipitating ammonium into struvite in composting matrix before it release to outside environment; the use of chemical and biological additives in the form of yeast, zeolite and alum; and the manipulation of key operational parameters during the composting process. The fact that struvite crystals were formed in manure composting media, as verified by both XRD and SEM-EDS analyses, represents novel findings from this study. This technique was able to reduce ammonia emission by 40-84%, while nitrogen content in the finished compost was increased by 37-105%. The application of yeast and zeolite with dosages of 5-10% enhanced the thermal performance of composting and the degree of degradation, and ammonia emission was reduced by up to 50%. Alum was found to be the most effective additive for both ammonia and odor emission control; ammonia emission decreased by 45-90% depending on the dosage, and odor emission assessed via an dynamic dilution olfactometer was reduced by 44% with dosages above 2.5%. This study reaffirmed that aeration is the most influential factor to odor emission. An optimal airflow rate for odor control would be 0.6 L/min.kg dry matter with an intermittent aeration system. Quantitative relationships between odor emission and key operational parameters were determined, which would enable “best management practices” to be devised and implemented for composting. An empirical odor predictive model was developed to provide a simple and direct means for simulation of composting odor emissions. The effects of operating conditions were incorporated into the model with multiplicative algorithm and linearization approximation approach. The model was validated with experimental observations.

Page generated in 0.029 seconds