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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

The sealing of non-woven geotextiles with cattle slurries /

Jazestani, Jamshid January 1997 (has links)
The clogging of fine-porosity geotextiles by soil particles is considered to be a problem in applications of these fabrics to filtering of municipal and industrial effluents. However, the clogging phenomenon can be an advantage for certain purposes, such as the creation of near-watertight membranes for sealing manure holding tanks. The conceived advantages of non-woven needle-punctured geotextiles are that they are less expensive due to lower material quantity, they are more resistant to tensile stresses compared to impermeable plastics and concrete, and they are easily installed. This thesis describes experimental work on the permeability and clogging characteristics of a Non-woven Polyester Geotextile with three different porosities (13.4, 19.5 and 26.0mum) but the same hydraulic conductivity (Kw = 10-5 m/s), when subjected to different heads of cattle slurry at 1, 2 and 4% total solids (TS) concentrations. The resulting infiltration rates were used to establish the effect of geotextile pore size and manure TS on geotextile sealing and to find the location of the seal, whether at the surface or within the geotextile. After 100 days of experimentation, the lowest infiltration rate of 1.1 L/m2/d was reached with the 13.4mum geotextile. Manure TS had a significant effect on the sealing and at least 4% TS was required to minimize the geotextile's infiltration rate. Clogging occurred within the pores, suggesting that the seal remains even after removing the manure. / This advantage can be translated into economic benefit when fun cost comparisons with sealing liners such as geomembranes and concrete are undertaken. / This research also reviews and analyzes the physical, chemical and biological processes leading to clogging of geotextiles as well as a cost-benefit comparison with the other sealing materials. The analysis concludes that clogged geotextiles are a wise choice for Canadian livestock producers.
52

Evaluation of nitrogen losses in the form of ammonia from surface applied manure

Brunke, Richard R. January 1986 (has links)
No description available.
53

Estimation of nitrogen mineralization from solid beef cattle and liquid swine manures

Sayem, S.M. 02 May 2014 (has links)
Manure nitrogen (N) mineralization is the process that converts organic N to plant available N and is influenced by environmental and soil factors. Field and laboratory incubation studies were conducted to determine the N mineralization and fertilizer equivalence of locally available manures. Available N from solid beef manure amendments (SBM) increased as the studies progressed due to mineralization. Liquid swine manure (LSM) behaved similarly to commercial fertilizer with high initial concentrations of ammonium N which declined continuously as the studies progressed. Manure N mineralization varied significantly (p<0.01) due to the influence soil moisture, manure types and study period as well as their interaction. The fertilizer equivalence of SBM in loamy soil was initially low compared to LSM and finally approached 80 % of ammonium nitrate fertilizer. These studies suggested that manure N mineralization requires emphasis on the initial form of N in manures besides soil moisture, soil temperature, and aeration.
54

Influence of a legume green manure crop on barley straw/stubble decomposition, and soil nitrogen retention and availability : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Applied Science at Lincoln University /

Kapal, D. B. January 2008 (has links)
Thesis (M. Appl. Sc.) -- Lincoln University, 2008. / Also available via the World Wide Web.
55

A preliminary study of a cattle waste lagoon

Lehner, Richard Allen, January 1900 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1965. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 45-49.
56

Ammonia emissions management and modeling from storages of dairy manure

Vaddella, Venkata Kumar. January 2010 (has links) (PDF)
Thesis (Ph. D.)--Washington State University, May 2010. / Title from PDF title page (viewed on June 3, 2010). "Department of Biological Systems Engineering." Includes bibliographical references.
57

Studies on the microflora of a cattle waste lagoon [Part I] Part II. Studies on the microflora of the feces from cattle.

Iwami, Marilyn Shigeko, January 1967 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1967. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
58

Phosphorus fertility in Northern Great Plains dryland organic cropping systems

Rick, Terry Lynn. January 2009 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: Clain Jones. Includes bibliographical references.
59

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
60

Evaluation of nitrogen losses in the form of ammonia from surface applied manure

Brunke, Richard R. January 1986 (has links)
No description available.

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