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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.
1

Evaluation of Nutrient and Pathogen Losses From Various Poultry Litter Storage Methods

Habersack, Mathew James 21 August 2002 (has links)
Considerable concern has developed over the possible pollution from poultry litter storage methods. This study was conducted to evaluate three different storage scenarios; covered stockpiles, uncovered stockpiles, and litter sheds. The stockpiles were monitored over two rainfall simulation events, in both the Ridge and Valley and the Piedmont physiographic provinces, with both surface and subsurface flows analyzed. An observational study, where subsurface water was sampled for a nine-month period was conducted using six litter sheds, three in each of the above provinces. Samples were analyzed for nutrients, fecal coliforms, and solids. Concentrations of NHx, TKN, OP, TP, VSS, and FC in surface runoff from uncovered litter piles were all statistically higher than that from covered piles, with NO3 being the exception. However, increased runoff volumes originating from the covered litter piles caused mass loadings from both covered and uncovered piles to be similar enough that statistical significance was not obtained, except in the case of FC. Soil water samples from litter stockpiles did not show a statistically significant treatment effect for concentration data, but uncovered piles did exhibit higher nitrogen concentration estimates than the covered piles. Sample collection frequency showed a statistically significant increase in the number of samples that could be obtained from the edge lysimeter under uncovered litter piles from the Piedmont experimental site. This result indicates uncovered piles are releasing the precipitation absorbed during the rainfall simulation into the sub-surface environment. In the storage shed study, a greater number of samples were collected per attempt at the Piedmont sheds compared to those at the Ridge and Valley site. While both areas were undergoing a significant drought, Piedmont porous-cup lysimeters yielded samples 63% of the time, compared to 10% for Ridge and Valley lysimeters. Lysimeters located near the edge of the shed were also more likely to yield a sample than those in the center or a background location. Unknown interferences within the litter shed samples prevented three laboratories from obtaining valid nutrient concentrations. / Master of Science
2

Porovnání jakosti vody na zemědělsky využívaném povodí v letech 1983 - 1985 a současným stavem. / Comparison of water quality on agricultural catchment in 1983 - 1985 and in present.

POKORNÁ, Zuzana January 2009 (has links)
There are remarkable changes in water quality at the Jenínský stream catchment that lies in the Šumava foothills which were caused by change in land use. Two subcatchments, called J1 and J2, were monitored. In the first period 1983-1985, the two subcatchments were agriculturaly used, the land was fertilized and ploughed and cereals and corn were grown. In the second period 2004-2008, there were grasslands and the land was extensively used as pasture. This change in land use caused evident changes in water quality at the Jenínský stream catchment. The decrease of all monitored indices was remarkably seen in the concentrations of nitrate and ammonium. The average nitrate concentration in 1983-1985 was 39,5 mg . l-1, and decreased by 43,3% to the value of 16,9 mg . l-1 in 2004-2008. The greatest decrease of 85,9% was found in average ammonium concentration (0,4 mg . l-1 dropped to 0,05 mg . l-1). The positive effect of the change from arable land to grassland was confirmed and we can see it in the amount of nitrogen compounds and resulting improvement of water quality.
3

Maumee River Watershed Farmers’ Perceptions of Nutrient Loss Risk

Schwab, Elizabeth Rose 07 October 2020 (has links)
No description available.
4

The Interaction of Aeolian and Fluvial Processes in Dry Washes on the Colorado Plateau, USA

Walker, Beau Jensen 01 December 2014 (has links) (PDF)
In the past decade there has been a call for integrated studies that examine the interaction of fluvial and aeolian processes (Belnap et al., 2011; Bullard and Livingstone, 2002). In this study, we examined the role of land-use, weather, and soil type on the flux of aeolian material into dry washes on the Colorado Plateau in central Utah, USA, and western Colorado, USA. Our goal was to quantify the impact of individual deposition and erosion events by correlating weather and land-use data with a combination of measurement methods including dust collection via dust traps, GPS surveying, and close-range photogrammetry. Our data suggest that there is an interaction between these processes and that seasonality and land-use play a large role in determining the strength of this interaction. Particularly, high land-use and dry, windy conditions were most conducive to the surface movement of sediment and subsequent removal of that sediment by fluvial processes.
5

Assessing the Effects of Conservation Practices and Fertilizer Application Methods on Nitrogen and Phosphorus Losses from Farm Fields – A Meta Analysis

Nummer, Stephanie Ann January 2016 (has links)
No description available.
6

Compostagem de resíduos agroindustriais: revolvimento, inoculação e condições ambientais / Composting of agroindustrial solid wastes: turning, inoculation and environmental conditions

Carneiro, Leocir José 21 February 2012 (has links)
Made available in DSpace on 2017-07-10T19:25:08Z (GMT). No. of bitstreams: 1 Leocir.pdf: 6158165 bytes, checksum: dbfdb8042a4030d3241c3f71a79f1525 (MD5) Previous issue date: 2012-02-21 / This trial aimed at testing the turning, cover courtyard and inoculation with a Commercial Biological Product (CBP) at the composite period and the produced compost quality using agro-industrial residues. The experiment was carried out at the Experimental Center of Agricultural Engineering (NEEA), at Western Paraná State University (UNIOESTE). The following wastes were used during the composting process from the activities developed by the Agricultural Cooperative Consolata - COPACOL: hatchery waste, flotation sludge, ash and remaining coal from boiler, solid fraction of swine manure, solid fraction of waste from trucks washing and waste from cleaning and pre-cleaning of cereals. Twelve treatments were performed and composed of three combinations of shift plowing frequencies with these conditions: uncovered and covered courtyard without and with CBP inoculation. The windrows were piled with 300 kg of weight each, so that each one could have the same composition. The pile temperature was daily monitored. The parameters as reduced mass, volume, total and volatile solids were weekly monitored. Electrical conductivity, pH, carbon and nitrogen were measured at the beginning, 28, 56 days and at the end of the process. The contents of P, K, Mg, Ca, Na, Zn, Cu, Mn and Fe were determined at the beginning and end of the composite process. The electrical conductivity, pH, carbon and nitrogen were measured at the beginning, at 28, 56 days and at the end of the process. The levels of P, K, Mg, Ca, Na, Zn, Cu, Mn and Fe were determined at the beginning and end of the composite process. The coverage at composite courtyard showed significant effect on volume and nitrogen decreases (p<0.05) and increases electrical conductivity, contents of Na, Mg, K and composite time (p <0.05). The use of frequent turnings at the beginning of the process allowed greater volume reduction and composting reduced the time within 20 days (p <0.05). However, there were greater losses of N, C, and consequently the C / N ratio. The frequency of shift plowing was twice a week on the first month (F2), so it was more effective in keeping nitrogen in the pile. The CBP use was not significant for any of the variables (p> 0.05) and pH, concentration of P, Ca, and micronutrients were not affected by any of the variables. / Esta pesquisa objetivou testar o turno de revolvimento, cobertura do pátio e inoculação com Produto Comercial Biológico (PCB) no tempo de compostagem e qualidade do composto produzido, utilizando resíduos agroindustriais. O experimento foi conduzido no Núcleo Experimental de Engenharia Agrícola (NEEA) da Universidade Estadual do Oeste do Paraná (UNIOESTE). Os resíduos utilizados no processo de compostagem, oriundos das atividades desenvolvidas pela Cooperativa Agrícola Consolata COPACOL foram: resíduo de incubatório, lodo de flotador, cinza e carvão remanescente da caldeira, fração sólida de dejeto de suíno, fração sólida do resíduo da lavagem de caminhões e resíduos da limpeza e pré-limpeza de grãos. Foram implantados doze tratamentos, compostos pelas combinações de três frequências de revolvimento, com as condições: sem e com cobertura do pátio; sem e com inoculação do PCB. As leiras foram montadas com 300 kg de massa fresca cada, com composição igual. A temperatura da leira foi monitorada diariamente. As variáveis redução de massa, volume, sólidos totais e voláteis foram monitoradas semanalmente. A condutividade elétrica, pH, carbono e nitrogênio foram mensurados no início, aos 28, 56 dias e ao final do processo. Os teores de P, K, Mg, Ca, Na, Zn, Cu, Mn e Fe foram determinados no início e final do processo de compostagem. A cobertura no pátio de compostagem teve efeito significativo nas reduções de volume e nitrogênio (p<0,05), além de aumentar a condutividade elétrica, os teores de Na, Mg, K e o tempo de compostagem (p<0,05). Os frequentes revolvimentos no início do processo possibilitaram maior redução de volume e reduziram o tempo de compostagem em até 20 dias (p<0,05). Entretanto, causaram maiores perdas de N, C e consequentemente da relação C/N. A frequência de revolvimento de duas vezes por semana no primeiro mês (F2) mostrou-se mais eficiente na manutenção de nitrogênio na pilha. O uso do PCB não foi significativo para quaisquer das variáveis analisadas (p>0,05). O pH, teores de P, Ca e micronutrientes não foram influenciados pelas variáveis.
7

Compostagem de resíduos agroindustriais: revolvimento, inoculação e condições ambientais / Composting of agroindustrial solid wastes: turning, inoculation and environmental conditions

Carneiro, Leocir José 21 February 2012 (has links)
Made available in DSpace on 2017-05-12T14:48:31Z (GMT). No. of bitstreams: 1 Leocir.pdf: 6158165 bytes, checksum: dbfdb8042a4030d3241c3f71a79f1525 (MD5) Previous issue date: 2012-02-21 / This trial aimed at testing the turning, cover courtyard and inoculation with a Commercial Biological Product (CBP) at the composite period and the produced compost quality using agro-industrial residues. The experiment was carried out at the Experimental Center of Agricultural Engineering (NEEA), at Western Paraná State University (UNIOESTE). The following wastes were used during the composting process from the activities developed by the Agricultural Cooperative Consolata - COPACOL: hatchery waste, flotation sludge, ash and remaining coal from boiler, solid fraction of swine manure, solid fraction of waste from trucks washing and waste from cleaning and pre-cleaning of cereals. Twelve treatments were performed and composed of three combinations of shift plowing frequencies with these conditions: uncovered and covered courtyard without and with CBP inoculation. The windrows were piled with 300 kg of weight each, so that each one could have the same composition. The pile temperature was daily monitored. The parameters as reduced mass, volume, total and volatile solids were weekly monitored. Electrical conductivity, pH, carbon and nitrogen were measured at the beginning, 28, 56 days and at the end of the process. The contents of P, K, Mg, Ca, Na, Zn, Cu, Mn and Fe were determined at the beginning and end of the composite process. The electrical conductivity, pH, carbon and nitrogen were measured at the beginning, at 28, 56 days and at the end of the process. The levels of P, K, Mg, Ca, Na, Zn, Cu, Mn and Fe were determined at the beginning and end of the composite process. The coverage at composite courtyard showed significant effect on volume and nitrogen decreases (p<0.05) and increases electrical conductivity, contents of Na, Mg, K and composite time (p <0.05). The use of frequent turnings at the beginning of the process allowed greater volume reduction and composting reduced the time within 20 days (p <0.05). However, there were greater losses of N, C, and consequently the C / N ratio. The frequency of shift plowing was twice a week on the first month (F2), so it was more effective in keeping nitrogen in the pile. The CBP use was not significant for any of the variables (p> 0.05) and pH, concentration of P, Ca, and micronutrients were not affected by any of the variables. / Esta pesquisa objetivou testar o turno de revolvimento, cobertura do pátio e inoculação com Produto Comercial Biológico (PCB) no tempo de compostagem e qualidade do composto produzido, utilizando resíduos agroindustriais. O experimento foi conduzido no Núcleo Experimental de Engenharia Agrícola (NEEA) da Universidade Estadual do Oeste do Paraná (UNIOESTE). Os resíduos utilizados no processo de compostagem, oriundos das atividades desenvolvidas pela Cooperativa Agrícola Consolata COPACOL foram: resíduo de incubatório, lodo de flotador, cinza e carvão remanescente da caldeira, fração sólida de dejeto de suíno, fração sólida do resíduo da lavagem de caminhões e resíduos da limpeza e pré-limpeza de grãos. Foram implantados doze tratamentos, compostos pelas combinações de três frequências de revolvimento, com as condições: sem e com cobertura do pátio; sem e com inoculação do PCB. As leiras foram montadas com 300 kg de massa fresca cada, com composição igual. A temperatura da leira foi monitorada diariamente. As variáveis redução de massa, volume, sólidos totais e voláteis foram monitoradas semanalmente. A condutividade elétrica, pH, carbono e nitrogênio foram mensurados no início, aos 28, 56 dias e ao final do processo. Os teores de P, K, Mg, Ca, Na, Zn, Cu, Mn e Fe foram determinados no início e final do processo de compostagem. A cobertura no pátio de compostagem teve efeito significativo nas reduções de volume e nitrogênio (p<0,05), além de aumentar a condutividade elétrica, os teores de Na, Mg, K e o tempo de compostagem (p<0,05). Os frequentes revolvimentos no início do processo possibilitaram maior redução de volume e reduziram o tempo de compostagem em até 20 dias (p<0,05). Entretanto, causaram maiores perdas de N, C e consequentemente da relação C/N. A frequência de revolvimento de duas vezes por semana no primeiro mês (F2) mostrou-se mais eficiente na manutenção de nitrogênio na pilha. O uso do PCB não foi significativo para quaisquer das variáveis analisadas (p>0,05). O pH, teores de P, Ca e micronutrientes não foram influenciados pelas variáveis.
8

DEJETOS LÍQUIDOS DE SUÍNOS: ESCOAMENTO SUPERFICIAL, ALTERAÇÕES NOS ATRIBUTOS QUÍMICOS E FÍSICOS DO SOLO E PRODUTIVIDADE DO FEIJÃO / SWINE LIQUID MANURE: SURFACE RUNOFF, CHANGES IN CHEMICAL AND PHYSICAL SOIL PROPERTIES AND BEANS PRODUCTIVITY

Pessotto, Patrícia Pretto 17 February 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The use of pig slurry as a source of nutrients for crops is a common practice in regions of pig production, however there is a growing concern about the risk of environmental contamination of soil and water as the continuous and excessive use of such waste. The purpose of this study was to evaluate losses of water, sediment and nutrients (N, P and Cu) through surface runoff and changes in chemical and physical attributes of a Red Oxisol under no-tillage system with continuous application of increasing doses of liquid pig manure (DLS) during the bean crop cycle. The study was conducted in an experimental area of the Federal University of Santa Maria campus Frederico Westphalen- RS, on a Red Oxisol, with a history of six years with DLS application. The treatments were: mineral fertilizer (NPK), organic fertilizer, consisting of DLS in doses of 25, 50, 75 and 100 m3 ha-1 and control without fertilization (0). Were evaluated surface runoff, loss of nutrients, chemical and physical properties of soil, productivity and crop yield components. The drained solution by natural rainfall was collected in gutters of 0.25 m2 installed in each plot, from October 2014 to January 2015. A sample of the drained volume was collected for measurement of sediment and concentrations of N, P and Cu present in the solution. Soil samples were collected for the determination of chemical parameters (N, P, K, Ca, Mg, Cu, Zn, MO, soil acidity indicators and total organic carbon) and physical parameters (aggregation, porosity and bulk density). The largest losses of soil, water and nutrients were observed from the beginning of sowing to the flowering of the culture, showing that little ground cover of the bean canopy is a determining factor for the runoff. Doses from 50 m3 h-1 DLS applied to the soil, associated with the application time, resulted in an increase of TOC content and enhance aggregation, porosity and density in the surface layer. The mineral fertilization of bean crops can be replaced by doses of DLS from 25 m3 ha-1, with no losses in maize productivity in an Red Oxisol clayey after six years of applying DLS. / A utilização de dejeto líquido de suínos como fonte de nutrientes para as culturas agrícolas é uma prática comum em regiões produtoras de suínos, entretanto há uma crescente preocupação quanto ao risco de contaminação ambiental do solo e água quanto à utilização contínua e excessiva desses resíduos. O objetivo deste estudo foi avaliar perdas de água, sedimentos e nutrientes (N, P e Cu) por escoamento superficial e alterações nos atributos químicos e físicos de um Latossolo Vermelho sob sistema plantio direto com aplicação contínua de doses crescentes dejetos líquido de suínos (DLS) durante o ciclo da cultura do feijão. O estudo foi desenvolvido em uma área experimental da Universidade Federal de Santa Maria, campus de Frederico Westphalen - RS, sobre um Latossolo Vermelho, com histórico de seis anos com aplicação DLS. Os tratamentos avaliados foram: adubação mineral (NPK), adubação orgânica, constituída de DLS nas doses de 25, 50, 75 e 100 m3 ha-1 e testemunha sem adubação (0). Foram avaliados o escoamento superficial, perda de nutrientes, atributos químicos e físicos do solo e produtividade e componentes de rendimento da cultura. A solução escoada por chuva natural foi coletada em calhas de 0,25 m2 instaladas em cada parcela de outubro de 2014 a janeiro de 2015. Uma amostra do volume escoado foi coletada para quantificação dos sedimentos e teores de N, P e Cu presentes na solução. Foram coletadas amostras de solo para a determinação dos atributos químicos (N, P, K, Ca, Mg, Cu, Zn, MO, indicadores de acidez do solo e carbono orgânico total) e físicos (agregação, porosidade e densidade do solo). As maiores perdas de solo, água e nutrientes foram observadas no início da semeadura até o florescimento da cultura, evidenciando que a pouca cobertura do solo pelo dossel vegetativo do feijão é um fator determinante para o escoamento superficial. As doses a partir de 50 m3 ha-1 de DLS aplicados ao solo, associados ao tempo de aplicação, implicaram em aumento dos teores de COT e, melhoram a agregação, porosidade e densidade do solo na camada superficial. A adubação mineral na cultura do feijão pode ser substituída por doses de DLS a partir de 25 m3 ha-1, sem que haja prejuízos na produtividade da cultura do milho em um Latossolo Vermelho de textura argilosa após seis anos de aplicação de DLS.
9

Respostas biomÃtricas e fisiolÃgicas de duas cultivares de feijÃo-de-corda sob irrigaÃÃo com Ãgua salina e potÃssio no solo / Biometrical and physiological responses of two cultivars cowpea under irrigation with saline water and potassium in the soil

Stella da Silva Prazeres 24 February 2012 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A intensidade do estresse causado pela salinidade nas culturas irà depender principalmente, do nÃvel de tolerÃncia da espÃcie vegetal e das formas de manejo utilizadas. O feijÃo-de-corda à uma cultura de importÃncia econÃmica, no entanto apresenta sensibilidade ao estresse salino. Dessa forma, objetivou-se avaliar as respostas biomÃtricas, fisiolÃgicas e produtivas de duas cultivares de feijÃo-de-corda, submetidas à irrigaÃÃo com Ãguas salinas e doses de potÃssio. O experimento foi conduzido em ambiente protegido na Ãrea experimental do Setor de Agrometeorologia da Universidade Federal do CearÃ. Foram utilizadas sementes de duas cultivares de feijÃo-de-corda (CE790 e CE104), as quais foram submetidas a nÃveis crescentes de salinidade, utilizando Ãgua de irrigaÃÃo com condutividade elÃtrica (CEa) de 0,8; 2,2; 3,6 e 5,0 dS m-1 e doses crescentes de potÃssio, utilizando 0,5, 1,0 2,0 e 4,0 g vaso-1 de Cloreto de PotÃssio. ApÃs coleta os dados foram submetidos a anÃlises estatÃsticas. O aumento da salinidade na Ãgua de irrigaÃÃo nÃo prejudicou o crescimento radicular das cultivares, por outro lado, a Ãrea foliar reduziu linearmente a cada incremento salino. A cultivar CE104 apresentou maior inibiÃÃo à acumulaÃÃo de Na+ com adiÃÃo de potÃssio. A salinidade afetou as trocas gasosas, das plantas de feijÃo-de-corda. Com a aplicaÃÃo de potÃssio houve uma menor perda hÃdrica e maior lixiviaÃÃo de Na+ nas plantas de feijÃo-de-corda sob estresse. / The strength of the stress caused by salinity in crops will depend largely on the level of tolerance of plant species and ways to employed manegement The cowpea is an of economic importance crop, however has sensitivity to salinity. This way, objective was to assess the responses biometric, physiological na production of two cultivars of cowpea, subject to irrigation with saline water and doses of potassium. The Experiment was carried in a protected environment at the experimental area the Sector of Agrometeorology, Federal University of CearÃ. The seeds used were two cultivars of cowpea (CE790 and CE104), which were subject to increasing salinity levels, used irrigation water with eletric conductivity (Eca) of 0,8; 2,2; 3,6 and 5,0 dS m-1 and increasing doses of potassium using 0,5; 1,0; 2,0 and 4,0 g pot-1 of potassium chloride. After collect the data was submitted to statistical analysis. The increase in the salinity in irrigation water did not impair to root growth of cultivars, however, the leaf Ãrea linearly reduced to each increase saline. The cultivar CE104 had highest inhibition to accumulation of Na+ with the addition of potassium. Gas exchanges been affected the effect of the salinity. As potassium application there was less water loss and higher leach of Na+ in cowpea plants under stress.
10

Theoretical and experimental study of a high rise hog building for improved utilization and environmental quality protection

Sun, Huawei 17 March 2004 (has links)
No description available.

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