• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 22
  • 5
  • 4
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 40
  • 40
  • 40
  • 14
  • 9
  • 7
  • 7
  • 7
  • 6
  • 6
  • 6
  • 6
  • 5
  • 4
  • 4
  • 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

COD balances in biological nutrient (nitrogen and phosphorus) removal activated sludge systems /

Copp, John B. January 1998 (has links)
Thesis (Ph.D.) -- McMaster University, 1999. / Includes bibliographical references (p. 185-188). Also available via World Wide Web.
22

Produtividade e acúmulo de nutrientes em forrageiras cultivadas no sistema de tratamento de esgoto doméstico por escoamento superficial / Productivity and nutrient accumulation in forages grown in the system of treatment of domestic sewage runoff

Nazário, Aline Azevedo 10 July 2012 (has links)
Made available in DSpace on 2016-12-23T14:37:31Z (GMT). No. of bitstreams: 1 Aline Azevedo Nazario.pdf: 1456108 bytes, checksum: e630765bf77652d52da4325ca3dae93c (MD5) Previous issue date: 2012-07-10 / O esgoto é um resíduo líquido resultante das atividades domésticas e industriais, com impurezas orgânicas e inorgânicas que se for lançado no ambiente sem tratamento adequado ocasiona diversos impactos ambientais negativos. A disposição de águas residuá-rias agroindustriais e domésticas no solo é uma técnica interessante, principalmente em condições de clima tropical e com disponibilidade de áreas, como é o caso do Brasil. Esta técnica se baseia na capacidade depuradora do sistema solo-planta para a de remoção dos poluentes contidos nas águas residuárias. Nesse sentido, o tratamento deste efluente faz-se necessário. Diante do exposto o presente trabalho teve como objetivo estudar os efeitos da aplicação de doses de esgoto doméstico bruto (EDB) no desenvolvimento de diferentes espécies de forrageiras, bem como avaliar o potencial destas forrageiras na redução da de-manda bioquímica de oxigênio (DBO) do esgoto doméstico bruto, a produção e o acúmulo de nutrientes das forrageiras. O experimento foi conduzido na área experimental do Centro de Ciências Agrárias da Universidade Federal do Espírito Santo (CCAUFES) onde em uma estrutura de alvenaria foram montadas 45 rampas de 1,0 x 0,2 m com declividade de apro-ximadamente 8%. O delineamento experimental utilizado foi montado no esquema de par-cela sub-subdividida 3x5x2, sendo nas parcelas espécies de forrageiras em três níveis (Brachiaria brizantha cv. Marandu; Cynodon sp. cv Tifton 85 e Paspalum atratum cv. Pojuca), nas subparcelas taxa de aplicação do esgoto domestico em cinco níveis (7,91; 15,82; 23,73; 31,64 e 39,55 kg ha-1 dia1 de DBO5 do EDB) e nas sub-subparcelas cortes do material vegetal em dois níveis (dois ciclos de 28 dias após o início da aplicação do EDB), num delineamento inteiramente casualizado com três repetições. Para acompanhar o de-créscimo da carga orgânica amostras do efluente foram coletadas nos pontos de entrada e saída das rampas (parte superior e inferior, respectivamente) para a determinação da DBO5. O material vegetal cortado foi encaminhado para laboratório onde foi determinada massa seca. O teor de proteína bruta foi obtido multiplicando-se o fator 6,25 pelo valor de nitro-gênio encontrado. O acúmulo de nutrientes foi obtido pelo produto dos teores de cada ele-mento pela produção total de matéria seca por hectare. Os resultados demonstraram que o sistema de tratamento empregado reduziu a carga orgânica do efluente de esgoto doméstico bruto em média 36% até os 28 dias e 12 % após os 28 dias, porém de forma não satisfatória para atender a legislação de lançamento de efluente em corpos hídricos, mostrando que as altas taxas de efluente de esgoto doméstico bruto requerem maior tempo de detenção nas rampas cultivadas com forrageiras. O rendimento aumentou proporcionalmente com in-cremento das aplicações das taxas de esgoto doméstico. O acúmulo de nutrientes para os cultivares Marandu, Tifton 85 e Pojuca estão acima dos mencionados em literatura para nitrogênio, fósforo, enxofre, manganês, ferro e cobre. Já para potássio, cálcio e magnésio estão de acordo com os valores médios relatados para as forrageiras. Esses resultados re-forçam o potencial desses capins quanto ao tratamento de águas residuárias, especialmente efluente de esgoto doméstico bruto / Sewage is the liquid waste with organic and inorganic impurities resulting from in-dustrial and domestic processes. The disposal of sewage in environment without proper treatment causes negative impacts, requiring a proper treatment of this effluent. The dis-posal of agro-industrial and domestic waste water in the soil is a promising residue treat-ment technique, particularly in tropical contries with availability of land such as Brazil. This technique relies on the ability of the soil-plant system to remove pollutants present in the waste water. The goal of the present work was to study the effects of the applied dose of gross domestic sewage (GDS) on the development of different forage species, and to assess the performance of forages to reduce biochemical oxygen demand (BOD) of domes-tic crude sewage production and to evaluate nutrient accumulation by the forage. The ex-periment was conducted in the experimental area of the Agricultural Science Center, Fed-eral University of Espírito Santo (CCAUFES). A masonry structure with 45 ramps, meas-uring 1.0 x 0.2 m each, was set upon a slope of approximately 8%. The experiment was set up in a 3x5x2 split-plot scheme in which we evaluated the following factors: three forage species (Brachiaria brizantha cv. Marandu; Cynodon sp. cv Tifton 85 and Paspalum atra-tum cv. Pojuca), five application rates of domestic sewage (7.91, 15.82, 23.73, 31.64 and 39.55 kg ha-1 day1 for BOD5 of GDS) and two harvest periods of forage, 28 and 56 days after the start of the GDS). The experimental design was completely randomized with three replications. To follow the variation of the organic content of the effluent, samples of ef-fluent were collected at points the entrance and exist of each ramp (top and bottom, respec-tively) for BOD5 analysis. The plant samples were sent to the laboratory where their dry weight was determined. The crude protein was obtained by multiplying the total nitrogen content found in the samples by a factor of 6.25. Nutrient accumulation was obtained by multiplying the contents of nutrients in the samples by the total production of dry matter per hectare. The results showed that the treatment system used reduced the organic content of the effluent from domestic sewage-tor crude in 36% until 28 days and 12% after 28 days after effluent application. However, this reduction in organic content is not sufficient to meet the current legal requirements of disposal of effluents in water bodies, indicating that a proper treatment of gross domestic sewage effluent would require longer long slopes to increase the period of treatment of these effluents. The forage yield increased along with the application rates of sewage. The accumulation of nitrogen, phosphorus, sulfur, manga-nese, iron and copper by the cultivars Marandu, Tifton 85 and Pojuca were higher than the average accumulation reported in the literature. Potassium, calcium and magnesium accu-mulation are in agreement with the average values found for forage. These results empha-size the potential use of these grasses to treat waste water, especially gross domestic sew-age effluent
23

Environmental applications of manometric respirometric methods

Roppola, K. (Katri) 22 April 2009 (has links)
Abstract In this work a manometric respirometric measuring system was applied to practical environmental cases related to wastewater management and biodegradation studies of oil-contaminated soils and materials used in landfill structures. Pollution of groundwater, surface water and soils is a worldwide problem. Therefore, tests simulating the biodegradation behaviour of organic compounds in water media and soils have become increasingly important. Respirometric methods provide direct measurement of the oxygen consumed by micro-organisms in biodegradation processes from an air or oxygen-enriched environment in a closed vessel. Biochemical oxygen demand (BOD) is a crucial environmental parameter used to measure the quality of water and treatment results in wastewater. Generally, BOD is measured with standardised methods, which are usually time-consuming as well as laborious. In this work the manometric respirometric test was compared with conventional BOD tests by determining the BOD of pulp and paper mills as well as domestic wastewater samples. The effect of different factors such as type, amount and pre-treatment of inoculum and the effect of dilution of a sample on the BOD values were also tested. A right dilution was noticed to be the most significant factor affecting the BOD values of the industrial wastewater samples. The mathematic estimation of the BOD7 values from the respirometric data was proved to work reliably after a 2–3 day incubation period. Characterisation of organic fractions of the pulp and paper mill wastewater was carried out with methods including filtration, long term BOD measurements and COD analyses. The most significant observation in characterisation analyses was that a remarkable part of the detected oxygen demand was consumed for the biotransformation of biodegradable fractions into new inert decomposition products, not only for mineralisation of the biodegradable COD fraction. Biodegradation behaviour of the peat samples with different decomposition rates was studied in order to evaluate the applicable peat types that can be used in landfill structures. Only minor (BOD/ThOD < 0.4%) biodegradation was observed with compaction peat samples, and the stable state, in which biodegradation stopped, was achieved during a two month period. The manometric respirometric method was also applied for the biodegradation studies in which the effect of the modification of soil properties on biodegradation rates of bio-oils was tested. Modified properties were the nutrient content and the pH of the soil. Fertiliser addition and pH adjustment increased both the BOD/ThOD% values of the model substances and the precision of the measurement. The manometric respirometric method was proved to be an advanced method for simulating biodegradation processes in soil and water media.
24

In-Stream water quality modelling and optimisation by mixed-integer programming : simulation and application in actual system

Mahlathi, Christopher Dumisani January 2013 (has links)
Water scarcity has become a global problem due to diminishing water resource and pollution of the remaining resources. The problems arising fromwater scarcity are exacerbated rapid urbanisation and industrialisation. Water quality management systems are introduced. Numerous water management methods exist some of which, if applied e ectively, can remedy these problems. In South Africa, water management systems are urgently needed to start addressing issues around the longterm sustainability of our limited water resource. Water quality modelling is one of the tools employed to assist in validating decisions made during the planning phase of a water quality management system. It also provides a means of exploring viable options to be considered when these decisions are to be made. A range of management options exist and implementing all of them may prove costly, therefore optimisation techniques are utilised to narrow down options to the most e ective and least costly among the available choices. Commonly, water quality models are used to predict concentrations in the river from which constraint equations are generated. The constraint equations are used in optimisation models to generate feasible solutions by either maximising or minimising the objective function. In this case the objective function is wastewater treatment cost. Constraints equations are based on the set in-stream water quality standard at selected theoretical measuring stations (checkpoints) in the stream and a feasible solution is one that suggests a treatment method that will ensure water quality standards are met at the lowest regional treatment cost. This study focused on the Upper Olifants river catchment near Witbank in Mpumalanga province. This catchment is subjected to extensive wastewater e uents from various mining operations and wastewater treatment plants. The aim here was to develop a water quality model for predicting dissolved oxygen (DO) concentration in the river, and to use a modelling approach to generate constraint equations for the system. A Streeter-Phelps stream simulation model was employed to predict DO concentration in the river. A mixed-integer programming technique was then used to evaluate the impact of nine wastewater treatment facilities discharging e uent into the river. Treatment levels were varied to test model reliability. The coupled stream simulation and optimisation model produced feasible solutions under 2 minutes, with each solution suggesting a range of treatment levels which ensured that the critical DO concentration was above 5 mg/L and the most stringent DO concentration the system could manage without violations anywhere else in the stream was obtained to be 7mg/L. / Dissertation (MEng)--University of Pretoria, 2013. / gm2014 / Chemical Engineering / unrestricted
25

Characteristics and Treatment of Landfill Leachate and Optimization of Leachate Oxidation with Fenton's Reagent

Gulati, Loveenia 17 June 2010 (has links)
The purpose of this study was to characterize the leachate from a landfill in Pennsylvania that had been pretreated by activated sludge and propose the most efficient treatment for this effluent. These samples had been pretreated in a sequencing batch reactor that also was operated to remove nitrogen by nitrification/denitrification. The SBR samples were found to have low BOD, high COD, high TOC and a very low BOD/COD ratio. These SBR decant samples have poor UV transmittance and hence quench UV light. Five treatment methods were evaluated, coagulation, ultrafiltration, combined coagulation/ultrafiltration, combined ultrafiltration/oxidation and combined filtration/fentons. These processes were tested for their ability to remove BOD and TOC and also to evaluate the improvement in UV transmittance. It was found that coagulation; Ultrafiltration and Ultrafiltration combined with coagulation do not work in improving the transmittance properties though there is a significant BOD and TOC removal with these processes. Ultrafiltration combined with oxidation was found to work the best in terms of TOC removal. In this study, four oxidants, KMnO?, H?O?, NaOCl and Fenton's reagent were used. It was observed that Fenton's reagent was capable of removing 90% TOC at a dose of 1g/L each of iron salt and hydrogen peroxide at a pH of 4.5. Since Fentons reagent was found to be the most effective method, hence, efforts were made to optimize the oxidation process with Fenton's. The two parameters which were studied were the initial pH and the chemical dosage. The initial pH was varied from a value of 2.5 to 6.5. The range of iron salt and peroxide dose used was from 0.05 to 0.1 g/L. Additional studies were conducted using samples filtered through a 0.45 um filter and oxidized with Fenton's reagent. The Fenton's process for oxidation of filtrates from the 0.45?m filter was also optimized with respect to pH and chemical dosage to determine the most economical operating conditions. The maximum transmittance of 57% was obtained for an iron dose of 0.075 g/L and a peroxide dose of 0.075 g/L at a pH of 4.5. This is in comparison to the transmittance of unoxidized 1K ultrafiltrate which was found to be 21.5%. There was a significant difference in the performance of 1K and 0.45um filtrates in terms of TOC removal and percentage transmittance. The oxidation process for improving the UV transmittance of leachate can therefore be economically optimized depending upon the desired efficiency by varying the operational parameters. / Master of Science
26

Biochemical oxygen demand reduction of semi-chemical neutral sulfite waste by heat hydrolysis

Butler, Robert George 11 May 2010 (has links)
The object or this experiment was to determine if and to what extent the B.O.D. of S.N.W. waste could be reduced by Heat Hydrolysis. This process gave B.O.D. reduction up to 80 percent when used on sulfite waste at Oregon State College and it was hoped that similar results could be obtained using S.N.W. liquor. The exper1mental part of the investigation was conducted to determine (1) it the B.O.D. content of S.N.W. liquor could be reduced by Heat Hydrolysis; (2) if pH, dilution and the addition of oxygen were factors that affected the reduction of B.O.D. These factors were determined by adjusting the raw liquor to the desired concentration and cooking the liquor in a closed container until certain conditions were obtained, namely, that of constant pressure with constant temperature. Ana1ysis of the raw and cooked liquor consisted of determining pH, total solids, and B.O.D., while analysis of the gas created during the cook was limited to the total amount of gas created and the amount of CO₂, CO, O₂ and H₂S in the gas. Four different series of cooks were conducted on each sample. They were, Neutral (raw liquor), Acid (raw liquor pH adjusted, Neutral-Oxygen added (raw liquor with oxygen added) and Ac1d-0xygen added (raw liquor pH adjusted with oxygen added). The samples used were 7OO ml., 465 ml., dilution 1:1 (232 ml. liquor plus 232 ml. distilled water) and dilution 2:1 (310 ml. distilled water plus 155 ml. liquor. / Master of Science
27

Physiological adaptations of microorganisms to high oxygen in two oligotrophic lakes

Mikell, Alfred Thomas January 1984 (has links)
Dissolved oxygen at four times normal saturation inhibited growth and metabolism of summer planktobacteria in surface waters of alpine oligotrophic Mountain Lake (Giles County, Virginia). Data included viable colony counts, D-[U-¹⁴C]glucose incorporation into extractable lipid of colonies, and respiration-assimilation of D-[U-¹⁴C]glucose by lake water samples. Significant (P<0.05) differences were not detected in either colony counts or ¹⁴C-lipid when superoxide dismutase (30 U ml⁻¹) or catalase (130 U ml⁻¹) were added to the medium. The upper waters of Lake Hoare, Antarctica, contain dissolved oxygen at ≥42 mg liter⁻¹ (=HDO). HDO did inhibit D-[U-¹⁴C]glucose assimilation-respiration compared with normal atmospheric dissolved oxygen (=ADO) in Lake Hoare water. D-[U-¹⁴C]glucose was assimilated and respired optimally at 12°C in Lake Hoare. Colony formation was inhibited in both lakes. Colonies represented <1% of the fluorochrome-stained direct counts in Lake Hoare. Lake Hoare planktobacteria were smaller than the planktobacteria in Mountain Lake. ATP size fractionation revealed that 39% of ATP biomass was <0.5 Hm in Lake Hoare. Five microbial isolates were selected from Lake Hoare by growth under very high oxygen (=VHO, 4.6x in situ HDO, 55 lb in⁻² of added oxygen). One isolate was selected under ADO from shallow benthic mat underlying HDO waters. Isolates were examined for physiological characteristics which might enhance their survival in the HDO environment. While HDO incubation produced <36% of ADO incubated CFU, VHO was more selective producing <1%. Bacterial isolates were motile Gram negative rods, catalase and oxidase positive, differing in their growth response to temperature and nutrient concentration. One VHO isolate was a yeast. HDO reduced the maximal cell density in three isolates tested at higher nutrient concentrations, however, all three exhibited less repression as nutrients were lowered from 1000-10 mg liter⁻¹ in comparison to ADO grown controls. One isolate actually produced a cell density 3x that of the ADO control. Four of five bacterial isolates demonstrated HDO inducible superoxide dismutase (SOD). The inducible and constitutive SOD were the manganese type and had the same electrophoretic mobilities in respective isolates. All VHO isolates contained carotenoids. Pigmentation of the bacterial isolates differed due to the types and relative proportions of the constituent carotenoids. A carotenoid-negative mutant of one isolate grown under HDO exhibited a lengthened lag phase, decreased growth rate, maximal cell density and thereafter increased lysis compared to the same ADO grown strain and the carotenoid containing parent strain. The mutant and parent strain produced catalase and indistinguishable specific activities of SOD. Microorganisms in the high oxygen Lake Hoare waters may be protected from oxygen toxicity by the lake’s oligotrophic nature as well as a combination of cellular defenses. / Ph. D.
28

Remoção microbiológica de nitrogênio, fósforo, DQO e DBO em uma estação de tratamento de efluentes numa fábrica de concentrados de bebidas

Oliveira, Suzane Silva de 16 April 2012 (has links)
Made available in DSpace on 2015-04-22T22:01:57Z (GMT). No. of bitstreams: 1 Suzane Oliveira.pdf: 2048877 bytes, checksum: 869e28ee9b61636d46a277f139c576e3 (MD5) Previous issue date: 2012-04-16 / It is essential that there is proper treatment of industrial wastewater before its release to the receiving body. Therefore, it is necessary to know which type of treatment to suit particular type of effluent generated, so that it can comply with the environmental regulations to prevent damage to the environment, such as water pollution. This study aimed to evaluate the efficiency of microorganisms to reduce the amount of organic matter (COD, BOD), nitrogen and phosphorus in an activated sludge system in an industry concentrates of non-alcoholic beverages during the period 2009 and 2010, featuring the effluent before and after analyzing the treatment, assessing also the major classes of microorganisms that participated in the process of removing nitrogen and phosphorus loads, BOD and COD, and statistically evaluate the process variables determining the ratio of the organic load factor / microorganisms. The physico-chemical analyzes were performed according to methods described in Standard Methods for the Examination of Water and Wastewater, 20th Edition (1998) and 21st Edition (2005). For data analysis techniques were used for statistical analysis of variance, and trend graphs and efficiency in order to check the possibility of optimizing the treatment. All data were tabulated and statistical methods were applied using Minitab software version 14.0. The results were analyzed using boxplots for the years 2009 and 2010, where there was greater removal efficiency for the parameters of color, COD, BOD and phosphorus. Correlated result Nitrogen ammonia versus Total Nitrogen, in which we observed greater efficiency in removing Total Nitrogen. Exploratory analysis of data for the two years studied show dendograms characterized by formation of groups have different type and characteristic result of the effluent generated during the production process in particular. The average efficiency station for removal of solids, COD, BOD, color, and phosphorus was 91%, 94%, 88%, 98% and 99% in 2009 and 95%, 95%, 95%, 99% and 98% in 2010, respectively, even with parameters ranging entry in the system was able to reduce them to values that met the legal requirements of CONAMA Resolution 357/2005. / É indispensável que haja o tratamento adequado dos efluentes industriais antes do seu lançamento ao corpo receptor. Para tanto, torna-se necessário saber qual tipo de tratamento se adequa a determinado tipo de efluente gerado, a fim de que se possa cumprir com a legislação ambiental vigente para evitar danos ao meio ambiente, como a poluição das águas. Este trabalho teve como objetivo avaliar a eficiência dos microorganismos em reduzir a quantidade de matéria orgânica (DQO, DBO), nitrogênio e fósforo em um sistema de lodos ativados em uma indústria de concentrados de bebidas não alcoólicas durante o período de 2009 e 2010, caracterizando o efluente antes e analisando-o após o tratamento, avaliando também as principais classes de microorganismos que participaram do processo de remoção das cargas de Nitrogênio e Fósforo, DBO e DQO, e avaliar estatisticamente as variáveis do processo determinando a relação do fator carga orgânica/microorganismos. As análises físico-químicas foram realizadas segundo as metodologias descritas no Standard Methods for the Examination of Water and Wastewater, 20th Edition (1998) and 21st Edition (2005). Para a análise dos dados usaram-se as técnicas estatísticas de análise de variâncias, além de gráficos de tendência e eficiência a fim de verificar a possibilidade de otimização do tratamento. Todos os dados foram tabulados e os métodos estatísticos foram aplicados usando programas do MINITAB versão 14.0. Os resultados obtidos foram analisados através de boxplots referentes aos anos de 2009 e 2010, onde observou-se maior eficiência de remoção para os parâmetros de cor, DQO, DBO e fósforo. Correlacionou-se resultado de Nitrogênio amoniacal versus Nitrogênio Total, no qual foi possível verificar maior eficiência em remoção de Nitrogênio Total. A análise exploratória dos dados relativos aos dois anos estudados mostram dendogramas caracterizados por ter a formação de grupos diferentes resultado do tipo e característica do efluente gerado pelo processo produtivo no período em específico. A eficiência média da estação para remoção de SST, DQO, DBO, cor e fósforo foi de 91%, 94%, 88%, 98% e 99% no ano de 2009 e 95%, 95%, 95%, 99% e 98% no ano de 2010, respectivamente, mesmo com parâmetros variando na entrada o sistema foi capaz de reduzi-los a valores que atendessem aos requisitos legais da Resolução CONAMA 357/2005.
29

Removal of wastewater cod and nitrogen using fibrous packing media

楊龍元, Yeong, Lung-yuen, Christopher. January 1991 (has links)
published_or_final_version / Civil and Structural Engineering / Master / Master of Philosophy
30

Produção e teor de nutrientes minerais de forrageiras cultivadas em rampas de tratamento de esgoto doméstico / Production and content of the mineral nutrient of forages grown on ramps treatment of domestic sewage

Milen, Larissa Cabral 31 July 2014 (has links)
Submitted by Morgana Andrade (morgana.andrade@ufes.br) on 2016-06-30T14:35:29Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Larissa Cabral Milen.pdf: 666421 bytes, checksum: 48d74190c050473dfe1b7d32a9089ebb (MD5) / Approved for entry into archive by Patricia Barros (patricia.barros@ufes.br) on 2016-07-11T19:05:02Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Larissa Cabral Milen.pdf: 666421 bytes, checksum: 48d74190c050473dfe1b7d32a9089ebb (MD5) / Made available in DSpace on 2016-07-11T19:05:02Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Larissa Cabral Milen.pdf: 666421 bytes, checksum: 48d74190c050473dfe1b7d32a9089ebb (MD5) / CAPES / A disposição de águas residuárias no solo é um método de tratamento que envolve mecanismos físicos, químicos e biológicos na remoção da carga orgânica e nutrientes contidos no efluente. Entre as técnicas de disposição no solo tem-se o escoamento superficial em rampas vegetadas, que se baseia na capacidade depuradora do sistema solo-planta para a remoção dos poluentes. Diante do exposto, objetivou-se com a realização deste trabalho estudar os efeitos da aplicação de esgoto doméstico bruto na produção e teor de nutrientes minerais em duas espécies de forrageiras adaptadas ao cultivo no outono/inverno. O experimento foi conduzido na área experimental do Centro de Ciências Agrárias da Universidade Federal do Espírito Santo (CCA-UFES) e montado no esquema de parcelas sub-subdivididas 2 x 2 x 3, sendo nas parcelas espécies de forrageiras em dois níveis: aveia preta (Avena strigosa Schreb.) e azevém (Lolium multiflorum Lam.), nas subparcelas taxas de aplicação de efluentes em dois níveis: 50 e 100 kg/ha/dia de demanda bioquímica de oxigênio (DBO5) e nas subsubparcelas seções da rampa de tratamento em três níveis: terço superior, terço intermediário e terço inferior, em um delineamento inteiramente casualizado com cinco repetições. O plantio das forrageiras foi feito em rampas de tratamento de 3,0 x 0,9 x 0,25 metros (comprimento, largura e profundidade), dispostas a uma declividade de 5%. As rampas foram preenchidas com um solo retirado do perfil natural de um Latossolo Vermelho-Amarelo. O material vegetal foi cortado após 30 dias de aplicação do efluente e encaminhado para o laboratório onde foi determinada massa seca e determinação dos teores foliares de nutrientes. De acordo com os resultados obtidos conclui-se que não houve efeito significativo para as variáveis analisadas na interação forrageira x taxa x seções da rampa. A aveia preta apresentou maior produção em massa seca, e obteve resposta positiva em relação ao aumento da taxa de esgoto doméstico aplicada; por sua vez, o azevém apresentou maior absorção de nutrientes, com exceção para o fósforo e manganês. A menor taxa de efluente aplicada proporcionou incremento no teor da maior parte dos nutrientes pelas forrageiras. No geral, as plantas apresentaram maior produção nas primeiras seções da rampa de tratamento, no entanto, este comportamento não foi observado no teor de todos os nutrientes. / The disposal of wastewater in the soil is a treatment method that involves physical, chemical and biological mechanisms in the removal of organic load and nutrients in the wastewater. Among the techniques disposal in the soil has the superficial runoff in vegetated ramps, based on the scrubbing capacity of the plant-soil system for the removal of pollutants. Given the above, the aim with this work was to study the effects of the application of raw domestic sewage in the production and content of the minerals nutrients in two grass species adapted to cultivation in the fall/winter. The experiment was conducted at experimental area of the CCAUFES and mounted on the sub-plot scheme 2 x 2 x 3 subdivided, and forage species in the plots of at two levels: black oat (Avena strigosa Schreb.) and ryegrass (Lolium multiflorum Lam.), the subplots application rates of effluent on two levels: 50 and 100 kg/ha/day biochemical oxygen demand (BOD5) and the sub-subplots of the ramp sections treatment at three levels: upper, middle and lower third, in a completely randomized with five replications. The planting of forage was done on the ramps of 3.0 x 0.9 x 0.25 meters (length, width and depth), disposed at a slope of 5%. The ramps were filled with soil taken from the natural profile of a Red-Yellow. The plant material was cut after 30 days of application of effluent and sent to the laboratory where it was determined dry mass and of foliar nutrients concentrations. According to the results it was concluded that there was no significant effect for any variable in interaction rate x forage x sections of the ramp. The oats showed higher dry matter production, and obtained positive response regarding the increasing rate of applied sewage; turn ryegrass showed higher absorption of nutrients, except for phosphorus and manganese. The lowest rate applied effluent provided an increase in the concentration of most of the nutrients by the forage. Overall, the plants showed higher production in the first sections of the ramp treatment, however, this behavior was not observed in the levels of all nutrients .

Page generated in 0.0464 seconds