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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.
21

A Survey of the Production and Marketing of Cattle Manure in Arizona

Stubblefield, Thomas M., Smith, Arthur H. 09 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
22

Impact of Rabon (R) oral-larvicide on the seasonal abundance of insects in dairy cow manure in a semi-arid area

Hurd, Mark Alan January 1977 (has links)
An intersive study of insect fauna in accumulated bovine manure was conducted from mid-Arpril through mid-October, 1975, on two dairy farms in the Mesa-Chandler area of south-central Arizona. Insect fauna was sampled by water flotation of manure, emergence trapping and resting fly counts. Musca domestica L. was the major noxious symbovine dipterous species collected. Tables of all predators, parasitoids, and scavenger groups collected are presented and seasonal abundance graphs for the primary inhabitants are included. In concert with the faunistic studies the effect of the feed additive insecticide stirofos (Rabon® oral-Larvicide, 2-chloro-1-(2,4,5-trichlorophenyl) vinyldimethyl phosphate) was evaluated. Reductions in fly population ranged from 27% to 87% depending upon the sampling method. Results of insecticidal activity on non-target groups are discussed and graphically depicted.
23

Forms and reactivity of manure phosphorus from phytase fed swine in Manitoba soils

Abioye, Olakulehin Stephen 14 September 2007 (has links)
Growing interests in dietary manipulation to reduce P excretion in animal manure and P loss from agricultural soils to the environment have led to strategies such as the use of phytase in monogastric animal diets. The efficacy of phytase has been confirmed by several studies that reported its ability to hydrolyze phytate P present in grain feeds and thus, reduce manure total P. However, the solubility of manure P from phytase supplemented diets in soils is not well known, and as thus, the environmental implications of dietary P manipulation require further investigation. Two related studies were carried out in the laboratory to investigate the fate of manure phosphorus (P) from pigs fed phytase supplemented diets in Manitoba soils. The first study characterized the forms of manure P from phytase supplemented swine diets to evaluate their potential environmental impact. The seven dietary treatments fed randomly to a total of 28 growing pigs were: a positive control that contained P at the NRC (1998) recommendations (NRC), a negative control (RED) containing 0.1 percentage units reduction (about 33%) in available P from 1998 NRC recommendations, RED with 500 U of phytase kg-1 of diet (RED + P1), RED with 1000 U of phytase kg-1of diet (RED + P2), a double negative control with no added inorganic P (DNC), DNC plus 2000 U of phytase kg-1 of diet (DNC + P3) and DNC plus 4000 U of phytase kg-1 of diet (DNC + P4). The second study examined the solubility of manure P from the manure collected from the first study. Manure collected from the first study were applied at a rate of 75 kg of total P ha-1 of soil to surface samples from four Manitoba soils (0-15 cm); Osborne clay (Rego Humic Gleysol/Gleysolic Humic Vertisol), Red River clay (Gleyed Rego Black Chernozem/Gleyed Humic Vertisol), Ladywood very fine sandy loam (Gleyed Dark Gray Chernozem), and Glenhope loamy fine sand (Gleyed Rego Black Chernozem). In the first experiment, total P in feces and manure were significantly reduced (p < 0.05) with phytase addition to the diets. The labile P concentration (sum of H2O–P and NaHCO3-P) was about 71 to 89% and 77 to 89% of total P in both feces and manure, respectively. Phytase addition to the diets reduced the labile P in feces. The solubility of P was greatest in the calcareous soils amended with the manure from the DNC diets and solubility of P varied with time and extracting solutions. Although, a combination of physico-chemical properties (e.g. CEC, Exchangeable Ca2+), texture seems to play a significant role, as P solubility increased in coarse textured soils after longer period of incubation (16wks). However, our results showed that phytase supplementation in the diets of pigs did not affect the solubility of manure P in amended soils.
24

Reclaiming phosphorus as struvite from hog manure

Ackerman, Joe January 2012 (has links)
The over application of manure phosphorus (P) to farmlands can lead to P build up in the soil and eventual runoff to surface waters causing eutrophication. Reducing P in manure by precipitation of struvite enables P capture and reuse as a fertilizer in the agricultural supply stream. Struvite precipitation is dictated by levels of soluble P which can be highly variable according to manure treatment and management. This research studied P forms in liquid pig manure, ways of increasing P-PO4 levels in manure from strategic storage conditions, novel struvite reactors, and the effectiveness of struvite as a fertilizer. Studies that monitored soluble nutrients during manure storage revealed that P-PO4 concentration was sensitive to pH and time. Anaerobic fermentation of manure increased P-PO4 by 2.5 fold with 12 days of storage, provided the buffering by alkalinity was low. Two different struvite reactors were operated, a batch-type system for processing lagoon supernatant and an upflow air sparged reactor that used supernatant from a rotary press solids separator. They achieved 75% and 31% total P removal, respectively. The upflow reactor operated without chemical addition at pH 6.8 to produce high purity struvite free of calcium phosphates. Costs of both reactors were comparable ($0.0139 and $0.0167/kg live pig wt) and similar to other pilot struvite reactors. Manure derived struvite was compared with pure struvite and commercial fertilizer for agronomic value in canola production. Results of a greenhouse pot experiment showed no significant difference between the two struvites despite impurities in the manure precipitate.
25

Forms and reactivity of manure phosphorus from phytase fed swine in Manitoba soils

Abioye, Olakulehin Stephen 14 September 2007 (has links)
Growing interests in dietary manipulation to reduce P excretion in animal manure and P loss from agricultural soils to the environment have led to strategies such as the use of phytase in monogastric animal diets. The efficacy of phytase has been confirmed by several studies that reported its ability to hydrolyze phytate P present in grain feeds and thus, reduce manure total P. However, the solubility of manure P from phytase supplemented diets in soils is not well known, and as thus, the environmental implications of dietary P manipulation require further investigation. Two related studies were carried out in the laboratory to investigate the fate of manure phosphorus (P) from pigs fed phytase supplemented diets in Manitoba soils. The first study characterized the forms of manure P from phytase supplemented swine diets to evaluate their potential environmental impact. The seven dietary treatments fed randomly to a total of 28 growing pigs were: a positive control that contained P at the NRC (1998) recommendations (NRC), a negative control (RED) containing 0.1 percentage units reduction (about 33%) in available P from 1998 NRC recommendations, RED with 500 U of phytase kg-1 of diet (RED + P1), RED with 1000 U of phytase kg-1of diet (RED + P2), a double negative control with no added inorganic P (DNC), DNC plus 2000 U of phytase kg-1 of diet (DNC + P3) and DNC plus 4000 U of phytase kg-1 of diet (DNC + P4). The second study examined the solubility of manure P from the manure collected from the first study. Manure collected from the first study were applied at a rate of 75 kg of total P ha-1 of soil to surface samples from four Manitoba soils (0-15 cm); Osborne clay (Rego Humic Gleysol/Gleysolic Humic Vertisol), Red River clay (Gleyed Rego Black Chernozem/Gleyed Humic Vertisol), Ladywood very fine sandy loam (Gleyed Dark Gray Chernozem), and Glenhope loamy fine sand (Gleyed Rego Black Chernozem). In the first experiment, total P in feces and manure were significantly reduced (p < 0.05) with phytase addition to the diets. The labile P concentration (sum of H2O–P and NaHCO3-P) was about 71 to 89% and 77 to 89% of total P in both feces and manure, respectively. Phytase addition to the diets reduced the labile P in feces. The solubility of P was greatest in the calcareous soils amended with the manure from the DNC diets and solubility of P varied with time and extracting solutions. Although, a combination of physico-chemical properties (e.g. CEC, Exchangeable Ca2+), texture seems to play a significant role, as P solubility increased in coarse textured soils after longer period of incubation (16wks). However, our results showed that phytase supplementation in the diets of pigs did not affect the solubility of manure P in amended soils.
26

Reclaiming phosphorus as struvite from hog manure

Ackerman, Joe January 2012 (has links)
The over application of manure phosphorus (P) to farmlands can lead to P build up in the soil and eventual runoff to surface waters causing eutrophication. Reducing P in manure by precipitation of struvite enables P capture and reuse as a fertilizer in the agricultural supply stream. Struvite precipitation is dictated by levels of soluble P which can be highly variable according to manure treatment and management. This research studied P forms in liquid pig manure, ways of increasing P-PO4 levels in manure from strategic storage conditions, novel struvite reactors, and the effectiveness of struvite as a fertilizer. Studies that monitored soluble nutrients during manure storage revealed that P-PO4 concentration was sensitive to pH and time. Anaerobic fermentation of manure increased P-PO4 by 2.5 fold with 12 days of storage, provided the buffering by alkalinity was low. Two different struvite reactors were operated, a batch-type system for processing lagoon supernatant and an upflow air sparged reactor that used supernatant from a rotary press solids separator. They achieved 75% and 31% total P removal, respectively. The upflow reactor operated without chemical addition at pH 6.8 to produce high purity struvite free of calcium phosphates. Costs of both reactors were comparable ($0.0139 and $0.0167/kg live pig wt) and similar to other pilot struvite reactors. Manure derived struvite was compared with pure struvite and commercial fertilizer for agronomic value in canola production. Results of a greenhouse pot experiment showed no significant difference between the two struvites despite impurities in the manure precipitate.
27

Anaerobic digestion strategies for dairy manures

Frear, Craig. January 2009 (has links) (PDF)
Thesis (Ph. D.)--Washington State University, August 2009. / Title from PDF title page (viewed on July 31, 2009). "Department of Biological Systems Engineering." Includes bibliographical references.
28

Aerobic digestion of farm animal wastes

Bizjak, Gerald John, January 1968 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1968. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
29

A soil sampling method to identify and rank critical manure management areas

Motschall, Robert M. January 1983 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1983. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
30

The role of night paddock manuring in the reduction of poverty and conflict amongst farmers and grazers in small Babanki (Cameroon) /

Ndikintum, Fouda Ndjinyo. January 2009 (has links) (PDF)
Thesis (M.Phil.) -- University of the Western Cape, 2005. / Includes bibliographical references (leaves 130-132).

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