Em muitas partes do mundo o aumento na demanda de água tem estimulado pesquisas relacionadas às práticas de reuso sustentáveis. Dentre as atividades humanas, a irrigação agrícola se revela como uma das práticas de maior consumo de recursos hídricos naturais. Uma alternativa para minimizar este problema é o reuso de efluentes gerados por sistemas biológicos de tratamento de esgotos. O objetivo desta pesquisa foi avaliar os efeitos da irrigação com esgoto tratado na dinâmica do carbono (C) e nitrogênio (N) e na atividade microbiana de um solo sob pastagem. O estudo foi conduzido em uma pastagem de capim-Bermuda Tifton 85 (Lins-SP), onde o delineamento experimental foi o de blocos completos com seis tratamentos: SI (sem irrigação e sem fertilização), A100 (água potável + 520 kg de N ha-1 ano-1); E0, E33, E66 e E100 (irrigação com esgoto tratado + 0, 33, 66 e 100% de 520 kg de N ha-1 ano-1). Os tratamentos receberam entre 420 a 1500 mm de esgoto tratado e água por ano, correspondendo a uma entrada pelo esgoto tratado de 640 a 2300 kg ha-1 ano-1 de C e de 135 a 480 kg ha-1 ano-1 de N. Utilizando como referência os estoques de C e N de SI, o menor decréscimo de C ocorreu em E33 (1,2 Mg ha-1) e o maior em A100 (7,9 Mg ha-1). Alterações no estoque de N do solo ocorreram após quatro anos de irrigação, onde A100 apresentou decréscimo de cerca de 450 kg de N ha-1. Os estoques de N dos tratamentos irrigados com esgoto tratado não foram afetados. A entrada de C e N orgânicos pelo esgoto tratado não afetaram a composição isotópica do C (\'delta\' 13C) e do N (\'delta\' 15N) da fração estável da matéria orgânica do solo (MOS) do solo. A alteração de \'delta\' 13C nos solos dos tratamentos irrigados (-0,7 a -1,2%o ), em relação a SI, foi resultante da mineralização do carbono orgânico remanescente do solo (plantas C3). Os valores de \'delta\' 15N do N da MOS (0 a 5 cm) foram significativamente maiores (+2,2%o) nos tratamentos irrigados com esgoto tratado do que em SI e A100, refletindo diferenciadas taxas e processos de ciclagem de N. A abundância natural de 15N nas folhas do capim-Bermuda refletiu a composição isotópica do N do solo, com enriquecimento de +2,5%o e +4,9%o em relação a A100 e SI, respectivamente. As taxas líquidas de mineralização e nitrificação negativas ou nulas nas épocas Seca-04, Chuvas-05 e Seca-05 indicaram predominância de processos de imobilização do N pela microbiota em virtude uma alta relação C:N da MOS. Nas épocas de Chuvas-06 e Seca-06 as taxas tornaramse positivas indicando a diminuição da relação C:N da MOS, término do efeito priming e, portanto, ciclagem interna de N. Os solos dos tratamentos apresentaram baixo consumo (-0,1kg de C ha-1 sem-1) ou pequena emissão média de CH4 (+0,8 kg de C ha-1 sem-1). A disponibilidade de N e a umidade do solo não representaram fatores limitantes nos tratamentos, assim as emissões de CO2 não diferiram entre si na maior parte das datas de coleta (médias de 14,7 e 12,2 Mg de C ha-1 para épocas de chuvas e seca, respectivamente). Os maiores fluxos de CO2 relacionaram-se com os períodos de maior precipitação e/ou irrigação do que com os tratamentos. Os maiores fluxos de N2O foram observados após a aplicação de N mineral nos tratamentos irrigados com esgoto tratado, sendo proporcionais as maiores quantidades de N adicionado. As relações médias entre o C da biomassa microbiana e o C orgânico total (Cmic:COT) dos tratamentos variaram de 2,3 a 3,8% ao longo das épocas, indicando boa resiliência do agroecossistema, onde os microrganismos apresentaram variações temporárias de biomassa. Interferências positivas do manejo (corte do capim e fertilização com N mineral) resultando em aumento de Cmic foram observadas no 1º ano hidrológico e Seca-06, como resultado da maior umidade do solo e com isso condições mais favoráveis para a disponibilização de C. Na Seca-04, com o aumento da atividade metabólica, e Chuvas-05, sem alteração deste parâmetro, ao longo do manejo, o quociente metabólico (qCO2) apresentou um cenário de eficiente conversão de C-CO2 em biomassa microbiana. No 2º ano hidrológico, com a diminuição das lâminas de irrigação os tratamentos irrigados e fertilizados apresentaram decréscimo de Cmic e respiração mantida (Seca-05) ou aumentada (Chuvas-06) após o manejo, os valores de qCO2 indicaram condições desfavoráveis a microbiota. Com a pouca interferência dos tratamentos, os indicadores eco-fisiológicos não foram suficientemente sensíveis para mostrar o manejo com menor impacto na qualidade do solo, revelando apenas cenários do metabolismo microbiano ao longo das práticas agrícolas. A quantidade de C exportada por E33, como biomassa (15,2 Mg de C ha-1 ano-1) não diferiu das maiores produções, a alteração em seu estoque de C foi inferior aos demais tratamentos irrigados, sugerindo ser o manejo mais sustentável, em termos de C, utilizando esgoto tratado como irrigação. Os tratamentos E100 (Seca-04) e E66 (Chuvas-05) representaram os manejos com as maiores exportações de N, respondendo linearmente até 940 ha-1 de N ano-1. De acordo com as variáveis avaliadas, o manejo com maior sustentabilidade produtiva e ambiental foi o tratamento E100, situação onde as saídas de N não superaram as entradas / In many parts of the world, the increasing demand and, especially in arid regions the natural scarcity of water has stimulated researches in terms of sustainable water reuse practices. Within human activities, common agricultural irrigation reveals one of the most consumptive practices of natural water resources. One alternative to minimize this problem represents the reuse of effluent generated by biological sewage treatment systems. The objective of this study was to investigate the impact of treated wastewater application in the dynamic of carbon (C) and nitrogen (N), and microbial metabolism of a soil under pasture. The study was carried out at Lins, São Paulo State, Brazil on a Tifton 85 bermudagrass pasture irrigated with secondary treated sewage effluent using a randomized complete block design with six treatments: SI (control, without irrigation and fertilization), W100 (potable water irrigation + 520 kg of N ha-1 year-1); E0, E33, E66 and E100 (treated wastewater irrigation + 0, 33, 66 and 100% of 520 kg of N ha-1 year-1). Samples of treated effluent/water, soil, plant (litter fall), and gases were taken from January 2004 through October 2007 and the treatments were kept under irrigation management receiving between 420 and 1,500 mm of water and treated sewage corresponding to an input of 640 to 2,300 kg ha-1 yr-1 of C and 135 to 480 kg ha-1 year-1 of N . Soil C stocks decreased slightly in the E33 treatment (-1.3 Mg ha-1) and a larger decrease was observed in W100 (-7.9 Mg ha-1). The inputs of organic C by the treated sewage did not affect the soil carbon isotopic composition (\'delta\' 13C), and in the irrigated treatments measured shifts in the isotopic signature (-0,7 a -1,2%o ) were caused by the mineralization of the remaining soil organic matter (SOC) (C3 plants). After 4 years of irrigation the only significant changes in soil N stocks were found in the W100 treatment (-450 kg de N ha-1). The \'deta\' 15N signature of the soil organic matter (0-5 cm depth) in the treatments irrigated with treated sewage was significantly higher (+2,2%o) than WI and W100, this suggests higher nitrogen cycling. The \'delta\' 15N signature of grass was enriched relative to the soil of W100 and WI +2,5%o and +4,9%o respectively). Negative or null rates of mineralization and nitrification occurred in the dry season of 2004, rainy and dry season of 2005 indicated an immobilization by the microorganisms, as a result of a high C:N ratio in the SOC. In the dry and wet seasons of 2006, mineralization and nitrification rates became positive suggesting a decrease of the C:N ratio, and the end of both priming effect and, thus the beginning of N cycling in the soil organic matter. Soils in the treatments showed low CH4 consumption rates (-0.1 kg de C ha-1 semester-1) and in some cases low emissions (+0.8 kg de C ha-1 emester-1). Nitrogen availability and soil moisture did not appear to be limiting factors for the treatments, thus CO2 emissions did not differ from each other over the collections (averages of 14.7 e 12.2 Mg of C ha-1 for wet and dry season, respectively). The highest CO2 fluxes were more related to periods of high precipitation and/or irrigation than to the applied treatments. The highest emissions of nitrous oxide were observed after the application of mineral N to the treatments irrigated with treated sewage, and the emissions were straightly related to the N addition. Values of Cmic:TOC (microbial C : Total Organic C) in the treatments averaged between 2.3 and 3.8 % through the seasons which means a significant resilience of the ecosystem, indicating that soil microbial community varied seasonally in their Cmic. Addition of mineral nitrogen and grass cutting practices influenced positively resulting in increase of Cmic in the first hydrological year and in the dry season in 2006, as well as an increase of soil moisture resulting in good conditions for C availability. With the increase metabolic activity in the dry season of 2004 and a continuous metabolic activity in the rainy season in 2005, the metabolic quotient (qCO2) resulted in an efficient scenario of conversion of C-CO2 into microbial biomass. In the second year, with a decrease of the irrigation depths and an increase in salts concentration after fertilization, the treatments irrigated with treated sewage and fertilizers presented decrease of Cmic with stable respiration (dry season 2005) or increase respiration (wet season 2006) after the management, and as a result qCO2 indicated inappropriate conditions for the microorganisms. In the dry season (2006) the physiological profile of the soil remained instable with no stress and Cmic increased and soil respiration remained inaltered. According to these results, the microbial indicators were not efficiently sensitive for revealing the more impacting management to the soil. The co-physiological indicators showed only the regular microbial metabolism along the agricultural practices. Carbon biomass exported by the grass in the E33 (15.2 Mg C ha-1 yr-1) did not differ from the biomass produced in the other treatments and the alterations in its C stocks were low compared to the other treatments. As a result, E33 seems to be the more sustainable and efficient practice for treated sewage use. Both the E66 and E100 treatments had high measured rates of N export, responding linearly up to 940 kg of N ha-1 yr-1. Thus, according to the variables studied, the management with highest sustainability was E100 where N outputs did not surpass the inputs

A crescente demanda de água nas cidades tem feito o homem buscar diferentes fontes de irrigação de culturas na agricultura, em se tratando de uma atividade que requer um grande montante de água. Neste contexto, o uso de efluente de esgoto tratado (EET), industrial ou doméstico, substituindo a água utilizada na irrigação de várias culturas, tem se mostrado ser uma medida promissora para preservá-la para o consumo humano.O propósito deste trabalho foi avaliar através de técnicas espectroscópicas (Infravermelho com Transformada de Fourier - FTIR, Espectroscopia de Fluorescência, Espectroscopia de Absorção de UV-Visível, Ressonância Paramagnética Eletrônica - RPE), as mudanças na matéria orgânica do solo (MOS) e ácidos húmicos (AH) extraídos de solo irrigado ou não com efluente de esgoto tratado, nas seguintes condições de irrigação: SI (sem irrigação com EET), 100 (irrigação com EET e umidade de solo na capacidade de campo) e 200 (irrigação com EET e umidade de solo 100% acima da capacidade de solo). Além dessas técnicas foi determinada a porcentagem de carbono e utilizada a espectroscopia de Fluorescência Induzida por Laser (FIL) para medir o grau de humificação de amostras de solo intacto, irrigados ou não com EET. As amostras de solo, sob cultura de cana-de-açúcar, foram coletadas em campo experimental situado em Lins-SP, em diferentes profundidades até 100 cm. As análises das amostras de solo demonstraram um decréscimo de porcentagem de carbono na faixa de 2 a 15% para as condições de irrigação com EET. O resultado é preocupante considerando tratar-se de solos com menos de 1% de conteúdo de carbono, e que tem com a aplicação do EET uma diminuição adicional na MOS, o que pode ser altamente limitante para a fertilidade e estrutura do solo. Os resultados obtidos por FIL para as mesmas amostras mostraram um aumento no grau de humificação variando de 9 a 30% nas áreas irrigadas com EET em relação às áreas não irrigadas com EET. Esse aumento do grau de humificação MOS é consistente com a diminuição de carbono do solo que mais provavelmente perde frações mais lábeis, permanecendo as mais recalcitrantes. Os espectros obtidos pela espectroscopia de FTIR para os AH analisados foram típicos, não mostrando diferença significativa, considerando as diferentes camadas de profundidade e irrigação ou não com EET. Os resultados obtidos por espectroscopia de fluorescência, usando três diferentes metodologias, de AH em solução mostraram, assim como a espectroscopia de FIL para amostras de solo, aumento no grau de humificação conforme aplicação de EET Assim como no caso da MOS, tal aumento no grau de humificação pode ser atribuído à degradação de frações de carbono mais lábeis e permanência das mais recalcitrantes dos ácidos húmicos analisados. Os resultados de razão E4/E6 (razão entre as intensidades de absorbância em 465 e 665 nm) para os AH analisados obtidos através da espectroscopia de absorção de UV-Visível denotaram decréscimo em seus valores nas camadas superficiais, comparando-se as três condições analisadas. Os resultados obtidos pela espectroscopia de RPE mostraram um aumento na concentração de RLS (radicais livres semiquinona) nos AH nas duas condições de irrigação, 100 e 200, sendo mais pronunciado na segunda. Corroborando com os resultados obtidos através das demais espectroscopias utilizadas, tal aumento da concentração de RLS provavelmente é oriundo de aumento de grau de humificação. Dessa forma, de acordo com os dados obtidos, o emprego de ET como fonte de irrigação em substituição à água, nas condições de solo analisadas são preocupantes, pois pode trazer limitações para a fertilidade e estrutura do solo, conforme evidenciado pelo decréscimo no conteúdo de MOS.Contudo, os experimentos devem ser continuados para confirmar e validar as tendências iniciais detectadas, bem como para buscar as alternativas de manejo dos solos e culturas para viabilizar a aplicação do EET em condições que sejam sustentáveis. / The increasing demand of water sources in the cities has done the man search for other different sources for irrigation of cultures in agricultural fields, hence it\'s an activity that demands a large amount of water. In this context, the use of treated sewage effluent (TSE), industrial or domestic, instead of water for irrigation of several cultures, has been shown to be a very promising way to save water for human consume.The purpose of this study is to evaluate by spectroscopic techniques (Fourier Transformed Infra-Red - FTIR, Fluorescence Spectroscopy, UV-Visible Spectroscopy and Electron Paramagnetic Resonance - EPR) the changes in the soil organic matter (SOM) and humic acids (HA) extracted from soils irrigated or not with treated sewage effluent, in the following concentrations of irrigation: SI (soil non-irrigated with TSE), 100 (soil irrigated with TSE and soil humidity in the same level of field capacity) and 200 (soil irrigated with TSE and soil humidity 100 % above field capacity). Besides these techniques, it was also determined the carbon percentage and used the Laser-Induced Fluorescence (LIF) spectroscopy to measure the degree of humification in samples of whole soil, irrigated or not with TSE. The soil samples analyzed in this study were collected from an experimental field in the city of Lins - SP, from a sugarcane culture soil, in the depth till 100 cm. The analysis of samples of whole soil showed a decrease in the carbon percentage in the range of 2 to 15% in the irrigation conditions comparing with the non - irrigated area. These results are preoccupying considering that it\'s a soil with less of 1% of carbon content, and has an additional decrease in the SOM when irrigated with TSE, what may cause limiting in the soil fertility and structure. The results obtained by LIF for the same samples, showed an increase in the humification degree varying from 9 to 30% in the irrigated area. This increase in the humification degree of soil organic matter (SOM) is consistent with carbon percentage decreasing in soil, which probably loses more labile fractions, remaining the most recalcitrant ones. The spectra obtained by the FTIR spectroscopy for HA analyzed were typical, not showing a significative difference, considering different layers of depth and treatment or not with TSE. The data obtained by fluorescence spectroscopy, using three different methodologies, of HA in solution showed, as well as the LIF spectroscopy for whole soils, an increment in the humification degree according to application of TSE. At the same way that happens with SOM, this increase in the humification degree may be attributed to degradation of carbon more labile fractions and remaining of the most recalcitrant ones in the humic acids. The results of E4/E6 ratio (ratio between the absorbance intensities at 465 and 665 nm) obtained by UV-Visible spectroscopy showed a decrease in the superficial layers, comparing the three conditions analyzed. The results obtained by the EPR spectroscopy showed an increase in the concentration of SFR (semiquinone free-radicals) in the HA with the increase of depth in the two conditions of irrigation, 100 and 200, being more pronunciated in the second treatment. Corroborating with the results obtained by the others spectroscopies, this increase in the SFR concentration probably may be attributed to the increase in the humification degree. In this manner, according with the obtained data, the use of TSE as source of irrigation replacing the water in the soil condition analyzed are preoccupying, hence it may cause limitations in soil fertility and structure, as evidenced by the decrease of the SOM content. However, the experiments must continue to confirm and validate the initials tendencies detected, and to search new alternatives for soil and culture tillage to make possible the TSE application in sustainable conditions.

This thesis reports on research from a full-scale demonstration project to recharge a depleted aquifer with treated sewage effluent from the Paphos (Cyprus) wastewater treatment plant. The project artificially recharged the Ezousas river basin, located in the south-western coastal plain of Cyprus, with tertiary treated, disinfected effluent through a network of artificial infiltration ponds. The aims of the research were to determine the capacity of the aquifer to provide a suitable buffer for the flow from the wastewater without flooding and to measure the changes in reclaimed water quality. The aquifer hydraulics and treatment capacity, including recharge basins, were analysed using field and laboratory measurements. A geological field survey and modelling was used to assess, both by practice and theory the effectiveness of the Ezousas river aquifer for storage and recovery of the reclaimed water. The aquifer was found to be mainly composed of alluvium with typical hydraulic characteristics. The average porosity was 20% and hydraulic conductivity around 90 m/day, it was concluded the aquifer would be able to accept all the annual output of the treatment plant which was 5 Mm3 /a. The recharge network consisted of five groups of infiltration basins arranged on both banks of the River Ezousas about 2km upstream of the wastewater treatment plant. Each infiltration basin contained two, four or six recharge ponds, each basin was 2,000m2 in area with a depth of 1.5 m. A recharge pattern consisting of alternating weeks of wet-fill and drying cycles was found necessary to maintain the unsaturated zone below the ponds in order to maximise the amount of water that could be recharged whilst optimising water quality. The hydraulic impact of the artificial recharge and extraction from the field measurements of borehole water levels indicated recharged water down to 15m below the surface. Tracer tests on the groundwater flow, capture zone, residence times and mass balances of recharged and native waters gave widely varying residence times between 30 days and 5 years, these were attributed to the complex flow patterns found. Recharged water was sampled using a series of extraction wells located along the downstream river basin, starting at the infiltration ponds and then at stages downstream. Eight production and monitoring wells were tested including control samples up-gradient (upstream) from the ponds, to about 7km down-gradient (downstream). Water quality was analyzed for the standard wastewater constituents including indicator organisms, organic matter, nutrients N and P and the metals. It was one of the recommendations of the thesis however that attention also be paid to the persistent organics, including the pesticides, biocides, plasticizers and pharma residues. The chemical data was used to build and validate a solute transport model of the ponds and surrounding area to predict the transport and fate of priority contaminants. In this way, the geo-chemical potential for the retardation, attenuation and chemical or biochemical degradation processes taking place in the unsaturated and saturated zone were assessed. From the results it was concluded that for most analytes, which included metals, nitrate and common salts, the main processes were mixing and dilution by the native ground water. The extracted water was then a mix of waters according to the different residence times and flow of natural groundwater, giving a stable water quality for irrigation. A third reaction involving cation exchange with the local geology was however identified which reduced the concentrations of copper and phosphate beyond what was expected from just mixing. It was also concluded that denitrification did not occur because of a combination of the high quality of the effluent, the operational cycling of the ponds and the high porosity of the vadose zone. Previous work has found denitrification if the recycled water still contains organic matter, further work was recommended to determine the critical organic concentrations. The renovated water from the Ezousas wastewater reuse Project was able to meet the health and agronomic requirements for unrestricted irrigation. The risk of flooding with sewage effluent resulting from hydraulic mounding was also investigated to define the growth and decay of the mound. It was possible to report that after more than fifteen years of operation and a total infiltration of 40Mm3, there have been no signs of reduced hydraulic capacity or water quality.

<p>The aim of this study was to compare the water quality of raw wastewater and treated sewage effluents from three different sewage treatment plants in the Western Cape, South Africa. The treatment plants investigated are on the same river system. Sewage treatment plant 1 and 2 use older technologies, while sewage treatment plant 3 has been upgraded and new technologies (membrane bioreactor) were incorporated in the treatment processes. The first objective was to determine the occurrence of total coliforms, Escherichia coli (E. coli) and fluoroquinolone and sulfamethoxazole antibiotic residues in raw wastewater and treated sewage effluents. Bacteria in treated sewage effluents can result in diseases such as dysentery, gastroenteritis, and typhoid upon exposure. A chromogenic test was used to screen for coliforms and E. coli. Enzyme linked Immunosorbent Assays (ELISA) were used to quantitate antibiotic residues (fluoroquinolones and sulfamethoxazole) in raw wastewater and treated sewage effluents. This study showed that bacteria are present in raw wastewater and residual bacteria are released with treated sewage effluents from sewage treatment plants.</p>

<p>The aim of this study was to compare the water quality of raw wastewater and treated sewage effluents from three different sewage treatment plants in the Western Cape, South Africa. The treatment plants investigated are on the same river system. Sewage treatment plant 1 and 2 use older technologies, while sewage treatment plant 3 has been upgraded and new technologies (membrane bioreactor) were incorporated in the treatment processes. The first objective was to determine the occurrence of total coliforms, Escherichia coli (E. coli) and fluoroquinolone and sulfamethoxazole antibiotic residues in raw wastewater and treated sewage effluents. Bacteria in treated sewage effluents can result in diseases such as dysentery, gastroenteritis, and typhoid upon exposure. A chromogenic test was used to screen for coliforms and E. coli. Enzyme linked Immunosorbent Assays (ELISA) were used to quantitate antibiotic residues (fluoroquinolones and sulfamethoxazole) in raw wastewater and treated sewage effluents. This study showed that bacteria are present in raw wastewater and residual bacteria are released with treated sewage effluents from sewage treatment plants.</p>

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No. of bitstreams: 1 louzada_isb_me_bot.pdf: 1671597 bytes, checksum: 1f1840203317416aa8d58af8cd8f3b90 (MD5) Previous issue date: 2016-09-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O uso de efluente de esgoto tratado e de lodo de esgoto compostado representam uma boa oportunidade para o setor agrícola de suprimento hídrico e nutricional às plantas, além da agricultura ser um destino adequado, seguro e benéfico desses resíduos quando corretamente manejados. Assim, objetivou-se com esse estudo avaliar o efeito da água residuária tratada e do lodo de esgoto compostado como substituto parcial, total e em doses superiores à adubação nitrogenada convencional, no solo e na cultura do crambe. O experimento foi conduzido em ambiente protegido em vasos de PVC com volume útil de 45,5 L, no Departamento de Solos e Recursos Ambientais, pertencente à Faculdade de Ciências Agronômicas da Universidade Estadual Paulista "Júlio de Mesquita Filho" (FCA/UNESP), Botucatu/SP, no período de julho à outubro de 2015. Foi utilizado um delineamento inteiramente casualizado em arranjo de parcelas subdivididas; nas parcelas foram empregados dois tipos de água para irrigação, água potável e efluente de esgoto tratado, e nas subparcelas sete níveis de adubação nitrogenada, totalizando quatorze tratamentos com dez repetições. Os tratamentos dentro de cada parcela são representados por: T0 – sem adubação nitrogenada; T1 – 100% de adubação nitrogenada mineral; T2 – 50% de adubação nitrogenada mineral + 50% adubação nitrogenada proveniente do lodo de esgoto compostado; e T3, T4, T5 e T6 correspondem à 100%, 150%, 200% e 250% da adubação nitrogenada proveniente do lodo de esgoto compostado, respectivamente. Os dados relativos às variáveis estudadas foram analisados estatisticamente por meio do software SISVAR e submetidos à análise de variância à 5% de probabilidade, sendo as médias comparadas pelo teste de Tukey a 5% de significância. Optou-se por refazer a análise estatística dos tratamentos que receberam somente lodo de esgoto compostado, adotando-se a análise de regressão. O uso de efluente de esgoto tratado proporcionou incremento dos componentes desenvolvimento, rendimento e teor de óleo da semente. A substituição da adubação nitrogenada convencional pela adubação via lodo de esgoto compostado elevou o rendimento de grãos-planta, com melhor rendimento proporcionado pela dose máxima de N aplicada via lodo de esgoto compostado. O aumento das doses de lodo de esgoto no solo elevou o pH, a CTC, SB, V%, os teores de matéria orgânica, P, K, Ca, S, B, Cu, Fe, Mn e Zn, e o uso de efluente de esgoto tratado os teores de Mg, S e Mn. / The usage of treated sewage effluent and composted sewage sludge represents a good opportunity for the agricultural sector of water supply and plant nutrition, besides being an adequate, safe and beneficial end for the agricultural for these residues when correctly handled. Thus, this study was aimed to evaluate the treated sewage effluent and the composted sewage sludge as a partial substitute, total and in doses superior to the conventional nitrogen fertilization, on the soil and on the crambe culture. The experiment was conducted in a protected environment of PVC vases with useful volume of 45,5L, at the Department of Soils and Environmental Resources of Agricultural Sciences Faculty, belonging to Universidade Estadual Paulista "Júlio de Mesquita Filho" (FCA/UNESP), Botucatu/SP, between July and October of 2015. The experimental design was completely randomized in a split plot arrangement; using the plots two types of irrigation water, potable water and treated sewage effluent and the subplots seven levels of nitrogen fertilization, adding up fourteen treatments with ten repetitions. The treatments within each parcel are represented by: T0 – no nitrogen fertilization; T1 – 100% mineral nitrogen fertilization; T2 – 50% mineral nitrogen fertilizer; + 50% composted sewage sludge; and T3, T4, T5, T6 corresponding to 100%, 150%, 200% and 250% of nitrogen fertilizer from the composted sewage sludge, respectively. The data concerning the variables were analyzed statistically through the SISVAR software and were submitted to a variance analysis to 5% of probability, being those averages compared using the Tukey test to 5% of significance. It was opted to redo the statistical analysis of the treatments that only had received the composted sewage sludge, adopting the regression analysis. The use of treated sewage effluent provided increment of components development and production. The conventional nitrogen fertilization substitution by the composted sewage sludge fertilizer elevated the yield of grains–plant, with a better yield provided by the maximum dose of N applied through the composted sludge. In the soil, the increasing doses of sewage sludge elevated the pH, the CTC, SB, V%, content of organic matter, P, K, Ca, S, B, Cu, Fe, Mn and Zn, and the usage of treated sewage effluent elevated the levels of Mg, S and Mn.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / The reuse of treated sewage on watermelon irrigation, variety Crimson Sweet, was investigated not only considering the sanitary aspects but also the productivity and final product quality. The experiment was conducted in the Research Centre on Wastewater Treatment and Reuse, owned by the Company of Water and Wastewater of CearÃ, in Aquiraz-CE. The experimental delimitation was randomized blocks, with four repetitions and four treatments: raw water and soil fertilization (T1); treated wastewater and soil fertilization (T2); treated wastewater without external soil fertilization (T3); and treated wastewater and half of soil fertilization (T4). The irrigation waters used (raw water and effluent of a stabilization pond) were characterized by the physical-chemical and microbiological aspects. Both waters were in the limits normalized by the World Health Organization (WHO) for unrestricted irrigation. The irrigation methods drip and furrow were compared in verifying of which one is more suitable for effluent reuse on watermelon production. The productivity data indicated that there was no significative difference among the treatments on drip irrigation, where the biggest productivities were obtained on T1 and T2 treatments. For the furrow system, no satisfactory productivity was achieved. The study revealed a significative difference among the treatments regarding the physical-chemical characteristics of the fruits. However, the microbiological quality was never compromised. Sensorial tests revealed that only the treatment T2 (treated wastewater and soil fertilization) did not present a different flavour, significative on 5% level, compared to the treatment T1 (control), and that the irrigation systems drip and furrow could be indifferently used without compromising the product flavour. / Investigou-se o reÃso de esgoto sanitÃrio tratado na irrigaÃÃo da cultura da melancia, variedade Crimson Sweet, tanto relacionado aos aspectos sanitÃrios como tambÃm à produtividade e à qualidade do produto final. O estudo foi realizado no Centro de Pesquisa sobre Tratamento de Esgoto e ReÃso de Ãguas da Companhia de Ãgua e Esgoto do Cearà em Aquiraz-CE. O delineamento experimental foi em blocos ao acaso, com quatro repetiÃÃes e quatro tratamentos: T1 - Ãgua do poÃo mais adubaÃÃo; T2 - efluente mais adubaÃÃo; T3 - efluente e T4 - efluente mais a metade da adubaÃÃo. As Ãguas de irrigaÃÃo utilizadas (Ãgua de poÃo e efluente de lagoas de estabilizaÃÃo) foram caracterizadas sob os aspectos fÃsico-quÃmicos e microbiolÃgicos, em que ambas estavam dentro dos limites estabelecidos pela OMS para irrigaÃÃo irrestrita. Os mÃtodos de irrigaÃÃo por gotejamento e sulco foram comparados para a verificaÃÃo do mais indicado para o reÃso com efluentes na cultura da melancia. Por meio de anÃlise dos dados de produtividade da cultura observou-se que nÃo houve diferenÃa significativa entre os tratamentos na irrigaÃÃo por gotejamento, sendo que os melhores resultados foram obtidos nos tratamentos T1 e T2. Para o sistema de sulco, nÃo foram obtidas produtividades satisfatÃrias. . O estudo indicou que houve diferenÃa significativa entre os tratamentos em relaÃÃo Ãs caracterÃsticas fÃsico-quÃmicas dos frutos produzidos, contudo, nÃo houve comprometimento da qualidade microbiolÃgica dos mesmos em nenhum dos tratamentos avaliados. Em relaÃÃo Ãs caracterÃsticas sensoriais observou-se, que somente as amostras que receberam o tratamento T2 (irrigaÃÃo com efluente mais adubaÃÃo) nÃo apresentaram sabor diferente, significativo ao nÃvel de 5%, quando comparadas Ãquelas submetidas ao tratamento controle (T1), e que os sistemas de irrigaÃÃo, sulco e gotejo, podem ser utilizados, indiferentemente, sem comprometer o sabor dos frutos produzidos

A crescente demanda de água nas cidades tem feito o homem buscar diferentes fontes de irrigação de culturas na agricultura, em se tratando de uma atividade que requer um grande montante de água. Neste contexto, o uso de efluente de esgoto tratado (EET), industrial ou doméstico, substituindo a água utilizada na irrigação de várias culturas, tem se mostrado ser uma medida promissora para preservá-la para o consumo humano.O propósito deste trabalho foi avaliar através de técnicas espectroscópicas (Infravermelho com Transformada de Fourier - FTIR, Espectroscopia de Fluorescência, Espectroscopia de Absorção de UV-Visível, Ressonância Paramagnética Eletrônica - RPE), as mudanças na matéria orgânica do solo (MOS) e ácidos húmicos (AH) extraídos de solo irrigado ou não com efluente de esgoto tratado, nas seguintes condições de irrigação: SI (sem irrigação com EET), 100 (irrigação com EET e umidade de solo na capacidade de campo) e 200 (irrigação com EET e umidade de solo 100% acima da capacidade de solo). Além dessas técnicas foi determinada a porcentagem de carbono e utilizada a espectroscopia de Fluorescência Induzida por Laser (FIL) para medir o grau de humificação de amostras de solo intacto, irrigados ou não com EET. As amostras de solo, sob cultura de cana-de-açúcar, foram coletadas em campo experimental situado em Lins-SP, em diferentes profundidades até 100 cm. As análises das amostras de solo demonstraram um decréscimo de porcentagem de carbono na faixa de 2 a 15% para as condições de irrigação com EET. O resultado é preocupante considerando tratar-se de solos com menos de 1% de conteúdo de carbono, e que tem com a aplicação do EET uma diminuição adicional na MOS, o que pode ser altamente limitante para a fertilidade e estrutura do solo. Os resultados obtidos por FIL para as mesmas amostras mostraram um aumento no grau de humificação variando de 9 a 30% nas áreas irrigadas com EET em relação às áreas não irrigadas com EET. Esse aumento do grau de humificação MOS é consistente com a diminuição de carbono do solo que mais provavelmente perde frações mais lábeis, permanecendo as mais recalcitrantes. Os espectros obtidos pela espectroscopia de FTIR para os AH analisados foram típicos, não mostrando diferença significativa, considerando as diferentes camadas de profundidade e irrigação ou não com EET. Os resultados obtidos por espectroscopia de fluorescência, usando três diferentes metodologias, de AH em solução mostraram, assim como a espectroscopia de FIL para amostras de solo, aumento no grau de humificação conforme aplicação de EET Assim como no caso da MOS, tal aumento no grau de humificação pode ser atribuído à degradação de frações de carbono mais lábeis e permanência das mais recalcitrantes dos ácidos húmicos analisados. Os resultados de razão E4/E6 (razão entre as intensidades de absorbância em 465 e 665 nm) para os AH analisados obtidos através da espectroscopia de absorção de UV-Visível denotaram decréscimo em seus valores nas camadas superficiais, comparando-se as três condições analisadas. Os resultados obtidos pela espectroscopia de RPE mostraram um aumento na concentração de RLS (radicais livres semiquinona) nos AH nas duas condições de irrigação, 100 e 200, sendo mais pronunciado na segunda. Corroborando com os resultados obtidos através das demais espectroscopias utilizadas, tal aumento da concentração de RLS provavelmente é oriundo de aumento de grau de humificação. Dessa forma, de acordo com os dados obtidos, o emprego de ET como fonte de irrigação em substituição à água, nas condições de solo analisadas são preocupantes, pois pode trazer limitações para a fertilidade e estrutura do solo, conforme evidenciado pelo decréscimo no conteúdo de MOS.Contudo, os experimentos devem ser continuados para confirmar e validar as tendências iniciais detectadas, bem como para buscar as alternativas de manejo dos solos e culturas para viabilizar a aplicação do EET em condições que sejam sustentáveis. / The increasing demand of water sources in the cities has done the man search for other different sources for irrigation of cultures in agricultural fields, hence it\'s an activity that demands a large amount of water. In this context, the use of treated sewage effluent (TSE), industrial or domestic, instead of water for irrigation of several cultures, has been shown to be a very promising way to save water for human consume.The purpose of this study is to evaluate by spectroscopic techniques (Fourier Transformed Infra-Red - FTIR, Fluorescence Spectroscopy, UV-Visible Spectroscopy and Electron Paramagnetic Resonance - EPR) the changes in the soil organic matter (SOM) and humic acids (HA) extracted from soils irrigated or not with treated sewage effluent, in the following concentrations of irrigation: SI (soil non-irrigated with TSE), 100 (soil irrigated with TSE and soil humidity in the same level of field capacity) and 200 (soil irrigated with TSE and soil humidity 100 % above field capacity). Besides these techniques, it was also determined the carbon percentage and used the Laser-Induced Fluorescence (LIF) spectroscopy to measure the degree of humification in samples of whole soil, irrigated or not with TSE. The soil samples analyzed in this study were collected from an experimental field in the city of Lins - SP, from a sugarcane culture soil, in the depth till 100 cm. The analysis of samples of whole soil showed a decrease in the carbon percentage in the range of 2 to 15% in the irrigation conditions comparing with the non - irrigated area. These results are preoccupying considering that it\'s a soil with less of 1% of carbon content, and has an additional decrease in the SOM when irrigated with TSE, what may cause limiting in the soil fertility and structure. The results obtained by LIF for the same samples, showed an increase in the humification degree varying from 9 to 30% in the irrigated area. This increase in the humification degree of soil organic matter (SOM) is consistent with carbon percentage decreasing in soil, which probably loses more labile fractions, remaining the most recalcitrant ones. The spectra obtained by the FTIR spectroscopy for HA analyzed were typical, not showing a significative difference, considering different layers of depth and treatment or not with TSE. The data obtained by fluorescence spectroscopy, using three different methodologies, of HA in solution showed, as well as the LIF spectroscopy for whole soils, an increment in the humification degree according to application of TSE. At the same way that happens with SOM, this increase in the humification degree may be attributed to degradation of carbon more labile fractions and remaining of the most recalcitrant ones in the humic acids. The results of E4/E6 ratio (ratio between the absorbance intensities at 465 and 665 nm) obtained by UV-Visible spectroscopy showed a decrease in the superficial layers, comparing the three conditions analyzed. The results obtained by the EPR spectroscopy showed an increase in the concentration of SFR (semiquinone free-radicals) in the HA with the increase of depth in the two conditions of irrigation, 100 and 200, being more pronunciated in the second treatment. Corroborating with the results obtained by the others spectroscopies, this increase in the SFR concentration probably may be attributed to the increase in the humification degree. In this manner, according with the obtained data, the use of TSE as source of irrigation replacing the water in the soil condition analyzed are preoccupying, hence it may cause limitations in soil fertility and structure, as evidenced by the decrease of the SOM content. However, the experiments must continue to confirm and validate the initials tendencies detected, and to search new alternatives for soil and culture tillage to make possible the TSE application in sustainable conditions.

Em muitas partes do mundo o aumento na demanda de água tem estimulado pesquisas relacionadas às práticas de reuso sustentáveis. Dentre as atividades humanas, a irrigação agrícola se revela como uma das práticas de maior consumo de recursos hídricos naturais. Uma alternativa para minimizar este problema é o reuso de efluentes gerados por sistemas biológicos de tratamento de esgotos. O objetivo desta pesquisa foi avaliar os efeitos da irrigação com esgoto tratado na dinâmica do carbono (C) e nitrogênio (N) e na atividade microbiana de um solo sob pastagem. O estudo foi conduzido em uma pastagem de capim-Bermuda Tifton 85 (Lins-SP), onde o delineamento experimental foi o de blocos completos com seis tratamentos: SI (sem irrigação e sem fertilização), A100 (água potável + 520 kg de N ha-1 ano-1); E0, E33, E66 e E100 (irrigação com esgoto tratado + 0, 33, 66 e 100% de 520 kg de N ha-1 ano-1). Os tratamentos receberam entre 420 a 1500 mm de esgoto tratado e água por ano, correspondendo a uma entrada pelo esgoto tratado de 640 a 2300 kg ha-1 ano-1 de C e de 135 a 480 kg ha-1 ano-1 de N. Utilizando como referência os estoques de C e N de SI, o menor decréscimo de C ocorreu em E33 (1,2 Mg ha-1) e o maior em A100 (7,9 Mg ha-1). Alterações no estoque de N do solo ocorreram após quatro anos de irrigação, onde A100 apresentou decréscimo de cerca de 450 kg de N ha-1. Os estoques de N dos tratamentos irrigados com esgoto tratado não foram afetados. A entrada de C e N orgânicos pelo esgoto tratado não afetaram a composição isotópica do C (\'delta\' 13C) e do N (\'delta\' 15N) da fração estável da matéria orgânica do solo (MOS) do solo. A alteração de \'delta\' 13C nos solos dos tratamentos irrigados (-0,7 a -1,2%o ), em relação a SI, foi resultante da mineralização do carbono orgânico remanescente do solo (plantas C3). Os valores de \'delta\' 15N do N da MOS (0 a 5 cm) foram significativamente maiores (+2,2%o) nos tratamentos irrigados com esgoto tratado do que em SI e A100, refletindo diferenciadas taxas e processos de ciclagem de N. A abundância natural de 15N nas folhas do capim-Bermuda refletiu a composição isotópica do N do solo, com enriquecimento de +2,5%o e +4,9%o em relação a A100 e SI, respectivamente. As taxas líquidas de mineralização e nitrificação negativas ou nulas nas épocas Seca-04, Chuvas-05 e Seca-05 indicaram predominância de processos de imobilização do N pela microbiota em virtude uma alta relação C:N da MOS. Nas épocas de Chuvas-06 e Seca-06 as taxas tornaramse positivas indicando a diminuição da relação C:N da MOS, término do efeito priming e, portanto, ciclagem interna de N. Os solos dos tratamentos apresentaram baixo consumo (-0,1kg de C ha-1 sem-1) ou pequena emissão média de CH4 (+0,8 kg de C ha-1 sem-1). A disponibilidade de N e a umidade do solo não representaram fatores limitantes nos tratamentos, assim as emissões de CO2 não diferiram entre si na maior parte das datas de coleta (médias de 14,7 e 12,2 Mg de C ha-1 para épocas de chuvas e seca, respectivamente). Os maiores fluxos de CO2 relacionaram-se com os períodos de maior precipitação e/ou irrigação do que com os tratamentos. Os maiores fluxos de N2O foram observados após a aplicação de N mineral nos tratamentos irrigados com esgoto tratado, sendo proporcionais as maiores quantidades de N adicionado. As relações médias entre o C da biomassa microbiana e o C orgânico total (Cmic:COT) dos tratamentos variaram de 2,3 a 3,8% ao longo das épocas, indicando boa resiliência do agroecossistema, onde os microrganismos apresentaram variações temporárias de biomassa. Interferências positivas do manejo (corte do capim e fertilização com N mineral) resultando em aumento de Cmic foram observadas no 1º ano hidrológico e Seca-06, como resultado da maior umidade do solo e com isso condições mais favoráveis para a disponibilização de C. Na Seca-04, com o aumento da atividade metabólica, e Chuvas-05, sem alteração deste parâmetro, ao longo do manejo, o quociente metabólico (qCO2) apresentou um cenário de eficiente conversão de C-CO2 em biomassa microbiana. No 2º ano hidrológico, com a diminuição das lâminas de irrigação os tratamentos irrigados e fertilizados apresentaram decréscimo de Cmic e respiração mantida (Seca-05) ou aumentada (Chuvas-06) após o manejo, os valores de qCO2 indicaram condições desfavoráveis a microbiota. Com a pouca interferência dos tratamentos, os indicadores eco-fisiológicos não foram suficientemente sensíveis para mostrar o manejo com menor impacto na qualidade do solo, revelando apenas cenários do metabolismo microbiano ao longo das práticas agrícolas. A quantidade de C exportada por E33, como biomassa (15,2 Mg de C ha-1 ano-1) não diferiu das maiores produções, a alteração em seu estoque de C foi inferior aos demais tratamentos irrigados, sugerindo ser o manejo mais sustentável, em termos de C, utilizando esgoto tratado como irrigação. Os tratamentos E100 (Seca-04) e E66 (Chuvas-05) representaram os manejos com as maiores exportações de N, respondendo linearmente até 940 ha-1 de N ano-1. De acordo com as variáveis avaliadas, o manejo com maior sustentabilidade produtiva e ambiental foi o tratamento E100, situação onde as saídas de N não superaram as entradas / In many parts of the world, the increasing demand and, especially in arid regions the natural scarcity of water has stimulated researches in terms of sustainable water reuse practices. Within human activities, common agricultural irrigation reveals one of the most consumptive practices of natural water resources. One alternative to minimize this problem represents the reuse of effluent generated by biological sewage treatment systems. The objective of this study was to investigate the impact of treated wastewater application in the dynamic of carbon (C) and nitrogen (N), and microbial metabolism of a soil under pasture. The study was carried out at Lins, São Paulo State, Brazil on a Tifton 85 bermudagrass pasture irrigated with secondary treated sewage effluent using a randomized complete block design with six treatments: SI (control, without irrigation and fertilization), W100 (potable water irrigation + 520 kg of N ha-1 year-1); E0, E33, E66 and E100 (treated wastewater irrigation + 0, 33, 66 and 100% of 520 kg of N ha-1 year-1). Samples of treated effluent/water, soil, plant (litter fall), and gases were taken from January 2004 through October 2007 and the treatments were kept under irrigation management receiving between 420 and 1,500 mm of water and treated sewage corresponding to an input of 640 to 2,300 kg ha-1 yr-1 of C and 135 to 480 kg ha-1 year-1 of N . Soil C stocks decreased slightly in the E33 treatment (-1.3 Mg ha-1) and a larger decrease was observed in W100 (-7.9 Mg ha-1). The inputs of organic C by the treated sewage did not affect the soil carbon isotopic composition (\'delta\' 13C), and in the irrigated treatments measured shifts in the isotopic signature (-0,7 a -1,2%o ) were caused by the mineralization of the remaining soil organic matter (SOC) (C3 plants). After 4 years of irrigation the only significant changes in soil N stocks were found in the W100 treatment (-450 kg de N ha-1). The \'deta\' 15N signature of the soil organic matter (0-5 cm depth) in the treatments irrigated with treated sewage was significantly higher (+2,2%o) than WI and W100, this suggests higher nitrogen cycling. The \'delta\' 15N signature of grass was enriched relative to the soil of W100 and WI +2,5%o and +4,9%o respectively). Negative or null rates of mineralization and nitrification occurred in the dry season of 2004, rainy and dry season of 2005 indicated an immobilization by the microorganisms, as a result of a high C:N ratio in the SOC. In the dry and wet seasons of 2006, mineralization and nitrification rates became positive suggesting a decrease of the C:N ratio, and the end of both priming effect and, thus the beginning of N cycling in the soil organic matter. Soils in the treatments showed low CH4 consumption rates (-0.1 kg de C ha-1 semester-1) and in some cases low emissions (+0.8 kg de C ha-1 emester-1). Nitrogen availability and soil moisture did not appear to be limiting factors for the treatments, thus CO2 emissions did not differ from each other over the collections (averages of 14.7 e 12.2 Mg of C ha-1 for wet and dry season, respectively). The highest CO2 fluxes were more related to periods of high precipitation and/or irrigation than to the applied treatments. The highest emissions of nitrous oxide were observed after the application of mineral N to the treatments irrigated with treated sewage, and the emissions were straightly related to the N addition. Values of Cmic:TOC (microbial C : Total Organic C) in the treatments averaged between 2.3 and 3.8 % through the seasons which means a significant resilience of the ecosystem, indicating that soil microbial community varied seasonally in their Cmic. Addition of mineral nitrogen and grass cutting practices influenced positively resulting in increase of Cmic in the first hydrological year and in the dry season in 2006, as well as an increase of soil moisture resulting in good conditions for C availability. With the increase metabolic activity in the dry season of 2004 and a continuous metabolic activity in the rainy season in 2005, the metabolic quotient (qCO2) resulted in an efficient scenario of conversion of C-CO2 into microbial biomass. In the second year, with a decrease of the irrigation depths and an increase in salts concentration after fertilization, the treatments irrigated with treated sewage and fertilizers presented decrease of Cmic with stable respiration (dry season 2005) or increase respiration (wet season 2006) after the management, and as a result qCO2 indicated inappropriate conditions for the microorganisms. In the dry season (2006) the physiological profile of the soil remained instable with no stress and Cmic increased and soil respiration remained inaltered. According to these results, the microbial indicators were not efficiently sensitive for revealing the more impacting management to the soil. The co-physiological indicators showed only the regular microbial metabolism along the agricultural practices. Carbon biomass exported by the grass in the E33 (15.2 Mg C ha-1 yr-1) did not differ from the biomass produced in the other treatments and the alterations in its C stocks were low compared to the other treatments. As a result, E33 seems to be the more sustainable and efficient practice for treated sewage use. Both the E66 and E100 treatments had high measured rates of N export, responding linearly up to 940 kg of N ha-1 yr-1. Thus, according to the variables studied, the management with highest sustainability was E100 where N outputs did not surpass the inputs

Philosophy of Doctor - PHD / The aim of this study was to compare the water quality of raw wastewater and treated sewage effluents from three different sewage treatment plants in the Western Cape, South Africa. The treatment plants investigated are on the same river system. Sewage treatment plant 1 and 2 use older technologies, while sewage treatment plant 3 has been upgraded and new technologies (membrane bioreactor) were incorporated in the treatment processes. The first objective was to determine the occurrence of total coliforms, Escherichia coli (E. coli) and fluoroquinolone and sulfamethoxazole antibiotic residues in raw wastewater and treated sewage effluents. Bacteria in treated sewage effluents can result in diseases such as dysentery, gastroenteritis, and typhoid upon exposure. A chromogenic test was used to screen for coliforms and E. coli. Enzyme linked Immunosorbent Assays (ELISA) were used to quantitate antibiotic residues (fluoroquinolones and sulfamethoxazole) in raw wastewater and treated sewage effluents. This study showed that bacteria are present in raw wastewater and residual bacteria are released with treated sewage effluents from sewage treatment plants. / South Africa