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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.
11

Modeling Salinity Impact on Ground Water Irrigated Turmeric Crop

Kizza, Teddy January 2013 (has links) (PDF)
Soils in irrigated fields are impacted by irrigation water quality. Salts in the irrigation water may accumulate in the soil depending on amount of leaching, the quality of water and type of ions present. Salinity is an environmental hazard that is known to limit agriculture worldwide. The quality of irrigation water is thus of concern to agriculturists. More so is the impact it has on productivity. The objective of this study was to quantify the impact due to use of ground water of such quality, with respect to salinity, as found in Berambadi watershed of Southern India, under farmers‟ field conditions. Turmeric (Curcuma Longa L.) was used for the study, based on salt sensitivity, under furrow irrigation. Study sites were selected basing on quality of water, with respect to salinity, crop and irrigation method. Samples of both soil and water were collected from each site and analyzed in the laboratory. The samples were analysed for salinity, alkalinity, pH and Cations of Magnesium, Sodium, Calcium and potassium as well as Chlorides and Sulfates. In addition soil was analysed for texture and Organic matter content. Non destructive plant monitoring for Leaf area (Index), number of leaves and plant height was done up to 210 days from planting. Profile, up to 80 cm depth, soil moisture was monitored at six plots using TDR and surface, up to 6cm depth, soil moisture for all the plots using Theta probe. Potential yield was obtained using STICS 6.9 crop model while field yield was estimated from rhizomes average weight of three plants. For both potential and observed yield estimation, a plant density of 9 plants per M2 was used. The quality parameters in water were correlated to soil parameters and to crop growth and ultimate yield. Impact due to salinity was then identified and quantified using relative yield. Identified quality problems in terms of turmeric response were, salinity, alkalinity and pH there was significant positive correlation between irrigation water salinity and soil salinity. Some wide scatter was observed and could be indicative of irrigation management practices, soil texture difference and other local variations. Observed turmeric yield was significantly negatively correlated to soil salinity. There was a monotonically increasing gap between simulated and observed yield as salinity increased. The maximum observed yield was 71% of the potential. The highest impact due to salinity was observed at 2.1 dS/m amounting to 44 % yield reduction. Excessive chlorosis due to iron deficiency occurred at 24.5% as CaCO3 and pH 7.5. Irrigation water pH was normal as per the guidelines. Soil pH was not so varied; it ranged between 7.1-7.9 except for one site where it was 6. Within the 7.1-7.9 range there was no effect on crop and yield observed. Interaction of stress factors observed was between salinity and alkalinity. The other was rhizome rot disease. Loss of yield to salinity was significant but farmers have no specific plans to leach out salts nor do they have an idea that ground water quality can actually negatively impact productivity. Salinity in irrigation water was in the moderately saline range. While that in the soil was low to slightly saline but could increase given the management practices.
12

Perda de carga em filtros de tela e de discos utilizados na irrigação localizada / Loading losses in net and disc filters used in dropping irrigation

Oliveira, Cleomar Ferreira de 23 January 2006 (has links)
Os sistemas de irrigação localizada requerem, obrigatoriamente sistemas de filtração para um tratamento mínimo da água. Os filtros são fundamentais à qualidade da água utilizada na agricultura irrigada, promovendo melhor desempenho dos sistemas de irrigação e seus componentes. Neste trabalho, estudou-se a perda de carga em função da vazão, em filtros de tela e de discos e determinou-se a bateria de filtros de mínimo custo anual total para diferentes vazões de projeto. Os ensaios foram realizados no laboratório de irrigação do Departamento de Engenharia Rural da Escola Superior de Agricultura "Luiz de Queiroz", Universidade de São Paulo, utilizando-se filtros comerciais da marca AMIAD, com elemento filtrantes de tela (modelos 3/4", 1", 1 ½" e 2") de discos (modelos 1", 1 ½" e 2"). A vazão máxima utilizada no ensaio, para cada modelo de filtro, foi àquela recomendada pelo fabricante. Para todos os filtros analisados no laboratório observaram-se altos valores dos coeficientes de determinação (R2) indicando uma forte relação potencial entre as variáveis vazão e perda de carga. Considerando as condições em que o estudo foi realizado e com base nos resultados obtidos, conclui-se que: o modelo matemático potencial descreve adequadamente a variação da perda de carga nos filtros de tela e discos em função da variação da vazão; os filtros de tela proporcionam menor perda de carga que os filtros de discos; a filtragem da água utilizando filtros de discos apresenta maior custo anual total; para os limites de vazão estudados e para as perdas de carga máximas permitidas, em geral as baterias compostas por filtros de 2" apresentaram o menor custo mínimo anual total; de forma geral, para os filtros estudados, as curvas de perda de carga em função da vazão apresentadas no catálogo do fabricante não representaram fielmente as curvas obtidas nesse trabalho, em ensaio de laboratório. / Drip irrigation systems always require filtration systems for a basic water treatment. The filters are fundamental for the water quality used in irrigated farming, providing better performance of irrigation systems and their components. It was studied in this work the loading loss according to the flow in net and disc filters and it was determined the filter sets with the minimum cost for different flows. The trials were carried out in the irrigation laboratory of the Rural Engineering Department of the Superior School of Agriculture "Luiz de Queiroz", São Paulo University, using AMIAD brand commercial filters, with net filtration elements (models 3/4", 1", 1 ½" ", and 2"), and discs (models 1", 1 ½" and 2").The maximum flow used in the trial, for each filter model, was that recommended by the manufacturer. It was observed for all the analyzed filters in the laboratory high values of determination coefficient (R2) indicating a strong potential relation between the flow and loading loss variables. Considering the conditions in which the study was carried out and based on the results obtained, it was concluded that: The potential mathematical model describes adequately the loading loss variation in the net and disc filters according to the flow variation; the net filters provide less loading loss than the disc filters; the water filtration using disc filters show higher total annual cost; for the studied flow limits and for the maximum allowed loading loss, in general the sets composed of 2" filters present the lowest total annual cost, overall, for the filters studied, the loading loss curves according to the flow showed in the manufacturer’s catalogue did not present accurately the curves obtained on this work in laboratory trial.
13

The Role of Rainfed Farm Ponds in Sustaining Agriculture and Soil Conservation in the Dry High Valley Region of Cochabamba, Bolivia: Design Considerations and Post Impoundment Analysis

Kuiper, John R. 08 1900 (has links)
Lack of sufficient water for irrigation is a major problem in and around the valleys surrounding the town of Aiquile, Cochabamba Bolivia. In addition, much of the region is undergoing desertification compounded by drought, deforestation, bad traditional agricultural practices, over grazing and a "torrential" rainfall pattern leading to severe soil erosion and low agricultural production. Between 1992 and 1994, the author constructed a network of 24 small, mostly rainfed farm ponds to increase agricultural production and alleviate soil erosion and land-use problems by improving cover conditions. A 5-year post-impoundment analysis was carried out in 1998. The analysis examined current pond conditions, design criteria, irrigation water / crop production increases and the alleviation of land-use problems. Current pond conditions fell into four distinct categories with only 25 percent of the ponds being deemed as "functioning well." The project increased irrigation in the region and improved cover conditions in 66 percent of the pond sites.
14

Mapping the environmental footprint of the Central Plains Water irrigation scheme : a thesis submitted in partial fulfilment of the Masters of Design at the Institute of Communication Design, Massey University, Wellington, NZ

Ivamy, Dean January 2009 (has links)
In the statement Mayor Parker is referring to a complexity of issues that involves a plethora of hard-scientific and statistical information. The diversity of opinions regarding the scheme’s benefits and potential negative implications also create misunderstanding for the general public. This prompts the hypothesis of this design thesis, which suggests that statistical data when visually mapped and in the context of its physical environment can provide significant cognitive and ecological awareness for the viewer to understand the economic and environmental implications of the proposed irrigation scheme. Both the areas of cartographic mapping and the dairy industry contain controlled vocabularies, which present opportunity for graphic modeling and explanation through visible phenomena. The Canterbury Plains has a well-established historical and agricultural narrative. However, due to the recent dramatic and substantial transition of the region’s dairy industry between the periods 1995 – 2008, subsequent demand for freshwater now represents the real prospect of uncharted future environmental instability. The development of a visual language system capable of the interpretation and construction of the irrigation scheme’s benefits and potential negative implications, provide this thesis through graphic modeling the possibility to compare the proposed CPW scheme’s issues. While some industry groups consider public participation as arbitrary and unnecessary, recent surveys indicate water quality and fertiliser management as the most significant areas for environmental concern. The debate should not exclude the public, but rather include communication systems capable of reaching all communities.
15

Avaliação de sistemas de tratamento e reúso de esgoto sanitário para fins de irrigação

Tomazela, Andréa Bogatti Guimarães [UNESP] 03 March 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-03-03Bitstream added on 2014-06-13T19:43:21Z : No. of bitstreams: 1 tomazela_abg_dr_botfca.pdf: 1126728 bytes, checksum: cc8ec5470f3eb8b5bf45fa957a450d18 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O presente trabalho teve como objetivo avaliar sistemas de tratamento de águas residuárias em áreas rurais, a fim de obter água com qualidade de reúso para irrigação. Os sistemas de tratamento foram montados na Fazenda Experimental Lageado localizada nas coordenadas 22o 55 S e 48o 26 W Gr, em Botucatu - SP/ Brasil. O primeiro sistema S1 envolveu tanque de sedimentação e sistema fitológico. O sistema S2 apresentou tanque de sedimentação, filtros anaeróbios e sistema fito-pedológico e o sistema S3 abrangeu tanque de sedimentação, reatores anaeróbios horizontais de leito fixo e sistema fitopedológico. No sistema fitológico S1, o índice de vazios da pedra britada foi de 0,456 e a vazão foi de 35,50+ 4,62 L h-1 a um tempo de detenção hidráulica de 13,2+ 1,92 h. A condutividade hidráulica saturada (Ks), volume de passagem (Vp) e porosidade nos leitos filtrantes do sistema fito-pedológico S2, que apresentavam ou não as camadas de areia grossa, foram, respectivamente de 7,0521 m h-1; 12,41 m3 h-1 e 0,46; a vazão de 43,05+3,41 L h-1 foi maior que a vazão de saída de 24,27+5,38 L h-1. Nas estruturas que compunham o sistema fito-pedológico S3, os resultados dos índices físicos foram de 7,0521 m h-1 (Ks), 7,26 m3 h-1 (Vp) e 0,46 (porosidade); os valores da vazão e do tempo de detenção hidráulica foram de respectivamente 5,26 L h-1; 44 h e 3,01 L h-1 e 76 h. Como bons parâmetros de desempenho e estabilidade dos sistemas de tratamento, os valores do pH apresentaram-se numa faixa adequada para o processo de digestão anaeróbia variando de 5,94 até 7,43, os da DQO, sólidos 2 em suspensão e P total sofreram reduções de até 90,5%; 87% e 72,7%, respectivamente e os do NTK apresentaram tendência de aumento de até 23,8%, na maioria das unidades de tratamento. A areia grossa não influiu nos valores da condutividade hidráulica saturada e nem na porosidade do leito... / The present work had as objective evaluates wastewater treatment systems in rural areas, in order to obtain water with quality for reuse in irrigation. The wastewater treatment systems were mounted in Experimental Farm located in the coordinates 22o 55 S and 48o 26 W Gr, in Botucatu - SP / Brazil. The first system S1 involved sedimentation tank and fitologic system. The system S2 presented sedimentation tank, anaerobic filters and fito-pedologic system and the system S3 included sedimentation tank, horizontal anaerobic immobilized biomass reactors and fito-pedologic system. In the fitologic system S1, the emptiness index of the broken stone was of 0,456 and the flow was from 35,50+ 4,62 L h-1 to a time of hydraulic detention of 13,2+ 1,92 h. The saturated hydraulic conductivity (Ks), passage volum (Vp) and porosith in the filtering bed of fito-pedologic system S2, that presented or no the layers of thick sand, were, respectively of 7,0521 m h-1; 4 12,41 m3 h-1 and 0,46; the flow of 43,05+3,41 L h-1 was larger than the flow of exit of 24,27+5,38 L h-1. In the structures that composed the fito-pedologic system S3, the results of the physical indexes were of 7,0521 m h-1 (Ks), 7,26 m3 h-1 (Vp) and 0,46 (porosith); the values of the flow and of the time of hydraulic detention were of respectively 5,26 L h-1; 44 h and 3,01 L h-1; 76 h. As good acting parameters and stability of the treatment systems, the values of the pH came in an appropriate strip for the anaerobic digestion process varying from 5,94 to 7,43, the one of DQO, suspension solids and P total suffered reductions of up to 90,5%; 87% and 72,7%, respectively and the one of NTK presented increase tendency of up to 23,8%, in most of the treatment units. The thick sand didn't influence on the saturated hydraulic conductivity values and neither in the bed porosith system, but it interfered in the acting of the fito-pedologic unit... (Complete abstract, click electronic address below).
16

Avaliação de sistemas de tratamento e reúso de esgoto sanitário para fins de irrigação /

Tomazela, Andréa Bogatti Guimarães, 1976- January 2006 (has links)
Orientador: Raimundo Leite Cruz / Banca: Célia Regina Lopes Zimback / Banca: Hélio Grassi Filho / Banca: Marcelo Zaiat / Banca: Guilherme Augusto Biscaro / Resumo: O presente trabalho teve como objetivo avaliar sistemas de tratamento de águas residuárias em áreas rurais, a fim de obter água com qualidade de reúso para irrigação. Os sistemas de tratamento foram montados na Fazenda Experimental Lageado localizada nas coordenadas 22o 55’ S e 48o 26’ W Gr, em Botucatu - SP/ Brasil. O primeiro sistema S1 envolveu tanque de sedimentação e sistema fitológico. O sistema S2 apresentou tanque de sedimentação, filtros anaeróbios e sistema fito-pedológico e o sistema S3 abrangeu tanque de sedimentação, reatores anaeróbios horizontais de leito fixo e sistema fitopedológico. No sistema fitológico S1, o índice de vazios da pedra britada foi de 0,456 e a vazão foi de 35,50+ 4,62 L h-1 a um tempo de detenção hidráulica de 13,2+ 1,92 h. A condutividade hidráulica saturada (Ks), volume de passagem (Vp) e porosidade nos leitos filtrantes do sistema fito-pedológico S2, que apresentavam ou não as camadas de areia grossa, foram, respectivamente de 7,0521 m h-1; 12,41 m3 h-1 e 0,46; a vazão de 43,05+3,41 L h-1 foi maior que a vazão de saída de 24,27+5,38 L h-1. Nas estruturas que compunham o sistema fito-pedológico S3, os resultados dos índices físicos foram de 7,0521 m h-1 (Ks), 7,26 m3 h-1 (Vp) e 0,46 (porosidade); os valores da vazão e do tempo de detenção hidráulica foram de respectivamente 5,26 L h-1; 44 h e 3,01 L h-1 e 76 h. Como bons parâmetros de desempenho e estabilidade dos sistemas de tratamento, os valores do pH apresentaram-se numa faixa adequada para o processo de digestão anaeróbia variando de 5,94 até 7,43, os da DQO, sólidos 2 em suspensão e P total sofreram reduções de até 90,5%; 87% e 72,7%, respectivamente e os do NTK apresentaram tendência de aumento de até 23,8%, na maioria das unidades de tratamento. A areia grossa não influiu nos valores da condutividade hidráulica saturada e nem na porosidade do leito... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The present work had as objective evaluates wastewater treatment systems in rural areas, in order to obtain water with quality for reuse in irrigation. The wastewater treatment systems were mounted in Experimental Farm located in the coordinates 22o 55’ S and 48o 26’ W Gr, in Botucatu - SP / Brazil. The first system S1 involved sedimentation tank and fitologic system. The system S2 presented sedimentation tank, anaerobic filters and fito-pedologic system and the system S3 included sedimentation tank, horizontal anaerobic immobilized biomass reactors and fito-pedologic system. In the fitologic system S1, the emptiness index of the broken stone was of 0,456 and the flow was from 35,50+ 4,62 L h-1 to a time of hydraulic detention of 13,2+ 1,92 h. The saturated hydraulic conductivity (Ks), passage volum (Vp) and porosith in the filtering bed of fito-pedologic system S2, that presented or no the layers of thick sand, were, respectively of 7,0521 m h-1; 4 12,41 m3 h-1 and 0,46; the flow of 43,05+3,41 L h-1 was larger than the flow of exit of 24,27+5,38 L h-1. In the structures that composed the fito-pedologic system S3, the results of the physical indexes were of 7,0521 m h-1 (Ks), 7,26 m3 h-1 (Vp) and 0,46 (porosith); the values of the flow and of the time of hydraulic detention were of respectively 5,26 L h-1; 44 h and 3,01 L h-1; 76 h. As good acting parameters and stability of the treatment systems, the values of the pH came in an appropriate strip for the anaerobic digestion process varying from 5,94 to 7,43, the one of DQO, suspension solids and P total suffered reductions of up to 90,5%; 87% and 72,7%, respectively and the one of NTK presented increase tendency of up to 23,8%, in most of the treatment units. The thick sand didn't influence on the saturated hydraulic conductivity values and neither in the bed porosith system, but it interfered in the acting of the fito-pedologic unit... (Complete abstract, click electronic address below). / Doutor
17

Perda de carga em filtros de tela e de discos utilizados na irrigação localizada / Loading losses in net and disc filters used in dropping irrigation

Cleomar Ferreira de Oliveira 23 January 2006 (has links)
Os sistemas de irrigação localizada requerem, obrigatoriamente sistemas de filtração para um tratamento mínimo da água. Os filtros são fundamentais à qualidade da água utilizada na agricultura irrigada, promovendo melhor desempenho dos sistemas de irrigação e seus componentes. Neste trabalho, estudou-se a perda de carga em função da vazão, em filtros de tela e de discos e determinou-se a bateria de filtros de mínimo custo anual total para diferentes vazões de projeto. Os ensaios foram realizados no laboratório de irrigação do Departamento de Engenharia Rural da Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, utilizando-se filtros comerciais da marca AMIAD, com elemento filtrantes de tela (modelos 3/4”, 1”, 1 ½” e 2”) de discos (modelos 1”, 1 ½” e 2”). A vazão máxima utilizada no ensaio, para cada modelo de filtro, foi àquela recomendada pelo fabricante. Para todos os filtros analisados no laboratório observaram-se altos valores dos coeficientes de determinação (R2) indicando uma forte relação potencial entre as variáveis vazão e perda de carga. Considerando as condições em que o estudo foi realizado e com base nos resultados obtidos, conclui-se que: o modelo matemático potencial descreve adequadamente a variação da perda de carga nos filtros de tela e discos em função da variação da vazão; os filtros de tela proporcionam menor perda de carga que os filtros de discos; a filtragem da água utilizando filtros de discos apresenta maior custo anual total; para os limites de vazão estudados e para as perdas de carga máximas permitidas, em geral as baterias compostas por filtros de 2” apresentaram o menor custo mínimo anual total; de forma geral, para os filtros estudados, as curvas de perda de carga em função da vazão apresentadas no catálogo do fabricante não representaram fielmente as curvas obtidas nesse trabalho, em ensaio de laboratório. / Drip irrigation systems always require filtration systems for a basic water treatment. The filters are fundamental for the water quality used in irrigated farming, providing better performance of irrigation systems and their components. It was studied in this work the loading loss according to the flow in net and disc filters and it was determined the filter sets with the minimum cost for different flows. The trials were carried out in the irrigation laboratory of the Rural Engineering Department of the Superior School of Agriculture “Luiz de Queiroz”, São Paulo University, using AMIAD brand commercial filters, with net filtration elements (models 3/4”, 1”, 1 ½” ”, and 2”), and discs (models 1”, 1 ½” and 2”).The maximum flow used in the trial, for each filter model, was that recommended by the manufacturer. It was observed for all the analyzed filters in the laboratory high values of determination coefficient (R2) indicating a strong potential relation between the flow and loading loss variables. Considering the conditions in which the study was carried out and based on the results obtained, it was concluded that: The potential mathematical model describes adequately the loading loss variation in the net and disc filters according to the flow variation; the net filters provide less loading loss than the disc filters; the water filtration using disc filters show higher total annual cost; for the studied flow limits and for the maximum allowed loading loss, in general the sets composed of 2” filters present the lowest total annual cost, overall, for the filters studied, the loading loss curves according to the flow showed in the manufacturer’s catalogue did not present accurately the curves obtained on this work in laboratory trial.
18

Efeito residual da adubação orgânica com torta de mamona e impactos do reuso de águas no sistema solo-planta. / Residual effect of organic fertilization with castor bean cake and impacts of water reuse on the soil-plant system.

SILVA, Leda Veronica Benevides Dantas. 02 July 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-07-02T14:15:49Z No. of bitstreams: 1 LEDA VERONICA BENEVIDES DANTAS SILVA - DISSERTAÇÃO PPGEA 2010..pdf: 8993633 bytes, checksum: 842487b79f8bc587c42403b8b5aa2ec0 (MD5) / Made available in DSpace on 2018-07-02T14:15:49Z (GMT). No. of bitstreams: 1 LEDA VERONICA BENEVIDES DANTAS SILVA - DISSERTAÇÃO PPGEA 2010..pdf: 8993633 bytes, checksum: 842487b79f8bc587c42403b8b5aa2ec0 (MD5) Previous issue date: 2010-02 / CNPq / A utilização de subprodutos na agricultura tem se tornado uma alternativa bastante promissora, uma vez que, ao conceder destinação a resíduos de alta carga orgânica, produzidos em diversas atividades humanas, permite amparar tanto ao aspecto ambiental quanto ao económico, proporcionando um elevado aporte de nutrientes às plantas, o que possibilita a redução dos custos com fertilização química. Este trabalho teve como objetivo avaliar o efeito residual da adubação orgânica com torta de mamona e os impactos da disposição de efluentes de esgoto tratado sobre as características químicas do solo e o desenvolvimento e produção do algodoeiro herbáceo, cultivado em sucessão a um ciclo de gergelim. Para isto, plantas de algodoeiro herbáceo foram cultivadas em vasos provenientes de cultivo anterior com plantas de gergelim submetidas a tratamentos que resultaram da combinação fatorial de cinco doses de torta de mamona no substrato (0, 2, 3, 4 e 5 ton ha"1), duas qualidades de água de irrigação (água de abastecimento e efluente doméstico tratado) além de dois tratamentos adicionais com adubação química (NPK + água de abastecimento e NPK + água residuária). O efeito residual das doses e fontes de fertilizantes aplicadas em primeiro ciclo e os impactos inerentes à aplicação das duas diferentes fontes de água de irrigação na cultura do algodoeiro e no sistema solo-planta foram avaliados por meio da determinação das variáveis de crescimento e produção da cultura, da caracterização química do solo ao final do experimento e da avaliação do estado nutricional das plantas de algodoeiro ao final do ciclo. Foi possível concluir que a irrigação com água residuária contribuiu para a redução da acidez do solo e elevação dos teores de fósforo e potássio no solo e na planta. Além disso, o efluente doméstico foi capaz de suprir parcialmente o teor de nitrogénio e completamente os teores de boro e ferro requeridos pelas plantas, contribuindo para o crescimento e produção do algodoeiro. Todavia, os teores de sódio na planta e no solo se elevaram devido à irrigação com água residuária. A torta de mamona aplicada em primeiro ciclo acarretou em efeito residual, tendo as crescentes doses do biofertilizante incrementado os teores de matéria orgânica, fósforo e ferro no solo, além de aumentarem a área foliar, altura, matéria seca da parte aérea e produção do algodoeiro herbáceo cultivado em segundo ciclo. / The use of byproducts in agriculture has become quite a promising alternative by providing a destination for the highly-organic waste materiais produced by a variety of human activities, it serves to bolster both environmental and economic factor, providing elevated leveis of nutrients to the plants which, in turn, brings about a reduction in the costs of chemical fertilization. The objective of this study was to evaluate the residual effects of organic fertilization using castor cake as well as the impact of the disposal of treated sewage effluents on the chemical properties of the soil and the development and production of cotton cultivated in succession to a crop of sesame plants. Cotton plants were cultivated in pots which had been previously used for the cultivation of sesame that had been submitted to treatments resulted from the factorial design of five leveis of castor cake in the substrate (0, 2, 3, 4 and 5 ton ha"1), two qualities of irrigation water (potable water and treated domestic effluent) in addition to two additional treatments with chemical fertilization (NPK + potable water and NPK + wastewater). The residual effect of the castor cake and fertilizer sources applied in the first cycle and the inherent impact of the application of the two different sources of irrigation water on the cotton crop and the plant- soil system were evaluated through the determination of growth and cotton production, soil chemical properties and nutritional state of cotton plants at the end of the cycle. It was possible to conclude that the irrigation with wastewater contributed to reduce the soil acidity and elevate phosphorous and potassium contents in the soil and plant. Additionally, the domestic effluent was capable of partially supplying the nitrogen content and completely supplying the leveis of boron and iron required by the plants, contributing to the growth and production of cotton. However, the sodium leveis were elevated plant and soil as a result of irrigation with potable water. The castor cake applied during the first cycle resulted in a residual effect, with the increasing leveis of biofertilizer increasing the organic material content, phosphorous and iron in the soil, in addition to increasing the leaf area, height, dry matter of the aerial part and cotton production during the second cycle.

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