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Estudo do comportamento dos resÃduos sÃlidos urbanos (RSU) em lisÃmetros preenchidos com resÃduos de diferentes caracterÃsticas / Study of the behavior of municipal solid waste (MSW) in lysimeters filled with different waste characteristicsAnna Kelly Moreira da Silva 26 July 2013 (has links)
nÃo hà / O biogÃs gerado nos aterros sanitÃrios apresenta elevado poder calorÃfico, podendo ser
aproveitado energeticamente. Para isso, fazem-se necessÃrios estudos sobre as emissÃes
desses gases para verificar a viabilidade econÃmica de seu reaproveitamento. Assim, esta
pesquisa teve como objetivo avaliar a geraÃÃo dos gases gerados no Aterro SanitÃrio
Metropolitano Oeste de Caucaia-CE, em termos de composiÃÃo e vazÃo, bem como as
caracterÃsticas do lixiviado gerado, por meio de suas propriedades fÃsico-quÃmicas e
microbiolÃgicas, como tambÃm avaliar a massa de lixo presente no aterro, objetivando a
viabilidade energÃtica do aproveitamento do biogÃs produzido pelo aterro e a viabilidade
ambiental do tratamento do lixiviado. As anÃlises foram feitas nos perÃodos seco e chuvoso.
Foram utilizados trÃs LisÃmetros: L1 â preenchido 100 % com os resÃduos sÃlidos na forma
como chegam ao aterro; L2 â preenchido com 50% de resÃduos sÃlidos na forma que chegam
ao aterro e 50% somente com matÃria orgÃnica; L3 â preenchido 100% somente com matÃria
orgÃnica presente nos resÃduos. Os resÃduos foram dispostos desta forma a fim de avaliar as
caracterÃsticas de diferentes composiÃÃes. Como resultados, foi observado que os ensaios
realizados nos LisÃmetros forneceram dados consistentes. Neste estudo, foi possÃvel observar
que os resÃduos se apresentaram com caracterÃsticas altamente degradÃveis no perÃodo seco,
porÃm, com pouca geraÃÃo de biogÃs, apresentando o L1 concentraÃÃo mÃdia de 0,3 % de
CH4, o CO2 com 0,7 % e O2 com 19,4%. O L2 com concentraÃÃo mÃdia de 0,3 % de CH4, o
CO2 com 9,0 % e O2 com 16,0%. E o L3 apresentou concentraÃÃo mÃdia de 1,93 % de CH4,
10,97% de CO2 e O2 com 14,13%. Estes dados foram considerados normais, pois, no perÃodo
seco, as mediÃÃes foram realizadas com pouco tempo de decomposiÃÃo da massa de lixo, com
apenas 4 meses apÃs a instalaÃÃo do experimento, e, devido a isso, ocorre pouca geraÃÃo de
gÃs. No perÃodo chuvoso, determinou-se aumento dessa geraÃÃo de gÃs, com o L1
apresentando concentraÃÃo mÃdia de 0,78 % de CH4, o CO2 com 1,63 % e O2 com 18,6%. O
L2 com concentraÃÃo mÃdia de 1,16 % de CH4, o CO2 com 5,6 % e O2 com 15,8%. E o L3
apresentou concentraÃÃo mÃdia de 2,43 % de CH4, 12,98% de CO2 e O2 com 15,25%. Isto Ã
considerado normal, pois, no perÃodo chuvoso, as mediÃÃes foram realizadas com 12 meses
apÃs a instalaÃÃo do experimento, e, consequentemente, houve uma maior geraÃÃo de gÃs em
relaÃÃo ao perÃodo seco. Em relaÃÃo a vazÃo, o L1 apresentou uma vazÃo de gÃs de 8,64
mÂ/ano, o L2 com vazÃo de 9,72 mÂ/ano e o L3 com vazÃo de 10,92mÂ/ano, possibilitando
conversÃo de energia em mÃdia, de 1,9 KW/mÂ. O material que se apresentou com o maior
potencial de geraÃÃo de biogÃs nos dois perÃodos foi o L3 (100% somente de matÃria
orgÃnica). Este fato se deve ao fato da matÃria orgÃnica, em seu processo de degradaÃÃo, gerar
mais gÃs. Os ensaios fÃsico-quÃmicos e microbiolÃgicos realizados no lixiviado e massa de
lixo, nos dois perÃodos, confirmaram os resultados da mediÃÃo do gÃs, pois indicaram que o
processo de biodegradaÃÃo dos resÃduos se encontrava na fase acidogÃnica no perÃodo seco,
fase inicial de degradaÃÃo da massa de lixo e pouca geraÃÃo de gÃs; no perÃodo chuvoso,
caracterizou-se como fase metanogÃnica, fase intermediÃria de degradaÃÃo, com uma maior
geraÃÃo de gÃs. Em relaÃÃo ao lixiviado gerado, o lisÃmetro que apresentou uma elevada
geraÃÃo nos dois perÃodos foi tambÃm o L3. Em relaÃÃo Ãs anÃlise microbiolÃgicas e de
metais, os lisÃmetros apresentaram pequenos valores, nÃo indicando patogenicidade e nem
toxicidade. Pode-se concluir que à de fundamental importÃncia investir em tÃcnicas de
aproveitamento do biogÃs gerado nos aterros sanitÃrios. / The biogas generated in landfills has a high calorific value and can be used as source of
energy. Therefore, studies on landfill gas emissions became necessaries in order to verify the
economic feasibility of reuse of these gases for energetic proposals. Thus, the present study
aimed to evaluate the emissions of gases generated by a landfill at the Metropolitan West
Caucaia-EC, Brazil. The study involved the following: gas compositions and flow rates, the
characteristics of the leachate released by the physico-chemical and microbiological activities,
as well as evaluating the landfill mass of trash. It was studied the feasibility of the use of the
landfill produced biogas as source of energy, as well as the environmental feasibility of the
treatment of the leachate released. The analyzes were made during the dry and rainy seasons.
Three types of lysimeters were used: L1 - 100% filled with waste solids as it arrives in the
landfill site; L2 - filled with 50% of solid waste in the form as it arrives in the landfill and
50% as organic matter; L3 - 100% filled only with organic matter present in the waste. The
residues were disposed in this way in order to evaluate the characteristics of the different
organic compositions. As a result, it was observed that the tests carried out with the lysimeters
provided consistent data. In this study, it was observed that the waste in the dry season
presented a highly degradable characteristic, but with little production of biogas, with the L1
presenting the following average concentrations: 0.3% CH4, 0.7% CO2 and 19.4% O2 . The
L2 average concentration were: of 0.3% CH4, 9,0 CO2 and 16% O2. And L3 showed
average concentrations: 1.93% CH4, 10.97% CO2 and 14.13%O2. These data were
considered normal, because in the dry period measurements were made with in a small period
of decomposition of the waste mass, with only four months after the experiment. Due to this,
there was small amount of gas generated. In the rainy season, it was determined an increased
gas generation, with the L1 showing an average concentration of 0.78% CH4, 1.63% CO2 and
18.6% O2. The L2 average concentration of 1.16% CH4, CO2, 5.6% and 15.8% O2. And L3
showed average concentration of 2.43% CH4, 12,98% CO2 and 15.25% O2. This data were
considered normal, because in the rainy season, the measurements were carried out 12 months
after the experiment was concluded, and, therefore, there was a higher gas generation
compared with the dry period. Regarding the L1, the flow showed a value of 8.64 m / year;
the L2 the flow was of 9.72 m / year and L3 the flow was 10.92 m / year, enabling energy
conversion averaged of 1.9 KW / mÂ. The material that presented the greatest potential for
biogas generation, in the two periods, was the L3 (with 100% organic matter). This fact is due
to the organic matter in the process of degradation which generated more gas. The physicochemical
and microbiological leaching assays conducted with the waste mass during the two
periods reaffirmed the results of the gas measurement, indicating that the biodegradation
process waste was in the acidogenic phase during the dry period, which was the initial stage
of mass garbage degradation with little gas generation; in the rainy season, which was
characterized as a methanogenic phase, an intermediate phase of degradation, occurred an
increased gas generation. With regard to the leachate produced, the material had a high
generation in both periods was also the L3. Regarding the microbiological and metals
analysis, the lysimeters showed small values, indicating no toxicity nor pathogenicity. It can
be concluded that it is of fundamental importance to invest in techniques aiming the use of the
biogas generated in the landfills.
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AvaliaÃÃo do comportamento de lisÃmetros preenchidos com resÃduos sÃlidos com diferentes caracterÃsticas / Lysimeters of performance evaluation filled with solid waste with different characteristicsFrancisco Amilcar Moreira JÃnior 02 February 2015 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / Esta pesquisa teve como objetivo avaliar o comportamento da massa de resÃduos sÃlidos em termos de produÃÃo de lixiviado, geraÃÃo de gases, avaliaÃÃo das propriedades fÃsico quÃmicas do efluente, caracterizaÃÃo dos resÃduos e recalque, para trÃs lisÃmetros em uma Ãrea pertencente ao Aterro SanitÃrio Metropolitano Oeste de Caucaia â CE. A pesquisa foi realizada durante os meses de janeiro a junho de 2014, dando continuidade ao monitoramento e caracterizaÃÃo das propriedades que ocorriam internamente aos LisÃmetros desde a sua implantaÃÃo em maio de 2012. Foram utilizados, para a avaliaÃÃo, trÃs LisÃmetros: L01 - preenchido com 100% de resÃduos na forma como chegam ao aterro sanitÃrio; L02 â preenchido com 50% de resÃduos orgÃnicos e 50% como chegam ao aterro sanitÃrio; L03- preenchido 100% com resÃduos orgÃnicos. Durante o perÃodo da pesquisa foi realizado um levantamento das precipitaÃÃes ocorridas no municÃpio pertencente ao aterro sanitÃrio, de forma a verificar a possÃvel interferÃncia desta na geraÃÃo dos gases e produÃÃo de efluentes. Como resultado foi observado a consistÃncia na produÃÃo de biogÃs, principalmente nos valores observados para metano na base dos lisÃmetros, de forma mais intensa, no L03, assim como a grande geraÃÃo de lixiviado, com o inconveniente do odor produzido pelo gÃs sulfÃdrico. Por jà se encontrarem hà aproximadamente dois anos em operaÃÃo, foram verificados altos valores de recalque dos resÃduos, sendo alcanÃada a mÃdia de 92 cm para o L01, 130,5 cm para o L02 e de 123,75 cm para o L03. Em termos de produÃÃo de metano, os valores mÃdios obtidos foram de 0,726% e 0,667 % para a base e o meio do L01, de 2,81% e 0,69% na base e no meio do L02, e de 4,8% e 1,966% no entorno da base e do meio do L03. Para os valores de diÃxido de carbono os valores alcanÃados, em mÃdia, para a base e o meio dos LisÃmetros foram de 2,041% e 0,132% no L01, 3,28% e 0,4% no L02 e 7,8% e 2,778% no L03. Jà quanto ao gÃs sulfÃdrico, foram obtidos os valores de 0,866 ppm e 0,917 ppm para o L01, de 5,14 ppm e 0,87 ppm para o L02, e de 164,2 ppm e 4,377 ppm na base e no meio do L03, respectivamente. Em termos das caracterÃsticas fÃsico-quÃmicas do lixiviado, foram encontradas variaÃÃes para determinados parÃmetros, principalmente durante os meses de maiores Ãndices de chuvas, afetando, desta forma, as caracterÃsticas da massa de resÃduos, na atividade dos microrganismos e na geraÃÃo do efluente, o qual se apresentou com valores bem acima do permitido em legislaÃÃo especÃfica para o lanÃamento em corpos hÃdricos. Mesmo com a presenÃa de adversidades, como o recalque excessivo, forte produÃÃo de lÃquidos, dois anos em decomposiÃÃo, e de fissuras na camada de cobertura, foi constatada, ainda, uma boa produÃÃo de gases, indicando a viabilidade e a importÃncia de se investir em tÃcnicas de aproveitamento de biogÃs em aterros sanitÃrios. / This research aimed to evaluate the behavior of the mass of solid waste in terms of leachate production, gas generation, evaluation of the physicochemical properties of the effluent, waste characterization and discharge for three lysimeters in an area belonging to the Landfill Metropolitan West Caucaia - CE. The survey was conducted during the months from January to June 2014, continuing the monitoring and characterization of the properties occurring internally to lysimeters since its inception in May 2012. It was used to evaluate three lysimeters: L01 - filled with 100% of waste in the way reach the landfill; L02 - filled with 50% of organic waste and 50% as they arrive to the landfill; L03- 100% filled with organic waste. During the research period was a survey of rain in the city belonging to the landfill in order to verify the possible interference in the generation of gases and waste production. As a result was observed consistency in the production of biogas, especially in the observed values of methane at the base of the lysimeters, more intensely, the L03, as well as the great generation of leachate, with the drawback of odor produced by hydrogen sulfide gas. As they were already there about two years in operation were high discharge values of waste, and achieved an average of 92 cm for the L01, 130.5 cm to L02 and 123.75 cm for the L03. In terms of methane production, the values obtained were 0.726% and 0.667% for the base and the middle of L01, 2.81% and 0.69% at the base and in the middle of L02, and 4.8 % and 1,966% in the vicinity of the base and the middle of the L03. For carbon dioxide the values obtained, on average, to the base of the lysimeters and the middle was 2.041% and 0.132% in the L01, and 3.28% to 0.4% and 7.8% and L02 2,778 % in the L03. As for the hydrogen sulfide was obtained values of 0.866 ppm and 0.917 ppm for L01, 5.14 ppm and 0.87 ppm for L02, and 164.2 ppm to 4,377 ppm at the bottom and in the middle of L03 respectively. In terms of physical and chemical characteristics of the leachate, variations were found for certain parameters, especially during the months of highest rates of rainfall, affecting in this way, the waste mass characteristics, the activity of microorganisms and the effluent generation, which performed with values well above the permitted in specific legislation for the release in water bodies. Even with the presence of adversity, such as excessive repression, strong production of liquid two years to decompose, and cracks in the cover layer, was found also a good gas production, indicating the viability and importance of investing in biogas production technologies in landfills.
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Valoração do impacto ambiental de cavas de mineração de areia e argila com base na evapotranspiração / Evaluation of the environmental impact of sand and clay mining pits based on evapotranspirationManoel Camilo Moleiro Cabrera 17 March 2016 (has links)
A atividade mineradora causa alterações na superfície, as quais influenciam a perda de água para atmosfera. Antes da instalação das cavas de mineração, há uma perda natural de água (evapotranspiração) da superfície. Com o aprofundamento da cava, essa área se torna uma lagoa, devido à surgência de água na cava proveniente do aquífero, e a evapotranspiração é alterada para evaporação. A quantificação da alteração no balanço hídrico devido às cavas é importante para se avaliar o impacto da mineração nos estoques hídricos subterrâneos e auxiliar no licenciamento e programas de recuperação de áreas degradadas pelas cavas. Este trabalho tem como objetivo quantificar experimentalmente as modificações nas variáveis do balanço hídrico; fornecer uma ferramenta de previsão das perdas evaporativas para o licenciamento ambiental em cavas de mineração e valorar economicamente o impacto dessa perda nas reservas hídricas subterrâneas. Para isso, foi utilizado um experimento composto por um lisímetro de drenagem com nível constante contendo solo argiloso (lis-arg) e outro arenoso (lis-aren), um tanque de evaporação com nível constante enterrado no solo (tenc), tanque de 20 m2 e o método de Penman-Monteith FAO-56. O monitoramento dos lisímetros foi feito durante 56 meses. Considerando períodos de quatro meses e fazendo a variação de armazenamento de água nos lisímetros igual a zero, conclui-se que a evapotranspiração da grama batatais nos lisímetros foi inferior a evaporação dos tanques e a evapotranspiração estimada pelo método padrão de Penman-Monteith FAO-56. A taxa de cobertura vegetal na área dos lisímetros que no inverno apresentava baixos índices, 50% da superfície evaporante, e a estimativa do saldo de radiação adotada pela FAO-56 que superestima o valor são as causas. A evapotranspiração do lisímetro com solo arenoso atinge uma relação unitária com a metodologia da FAO-56 quando se muda a forma de estimar o saldo de radiação, adotando este como 48% da irradiância solar global e apenas no período de novembro a fevereiro (exceto março a junho de 2015). A drenagem dos lisímetros com solo argiloso e com solo arenoso apresentaram valores semelhantes, e ambos foram em média 50% da precipitação. Para a fase de licenciamento ambiental de cavas de mineração a relação linear 0,9ND, sendo ND o número de dias após o surgimento da área alagada na cava, pode ser utilizado para prever a lamina de água perdida do armazenamento subterrâneo para a atmosfera. A relação citada foi obtida em uma superfície gramada com solo arenoso e outra de água livre num clima tropical úmido, com baixa deficiência hídrica no inverno, e com uma evapotranspiração média de 3,3 mm/dia. Durante o licenciamento ambiental essa metodologia pode prever impactos (perdas evaporativas) devido à instalação e aumento das cavas de mineração. Nos programas de recuperação de áreas degradadas o impacto nos recursos hídricos subterrâneos devido à mudança de superfície feito durante a atividade minerária pode ser quantificado com essa simples relação (0,9ND). O método requer apenas a medição da área convertida em superfície de água livre, para isto podem ser usadas imagens de satélite e a relação acima descrita. Aplicou-se o método nas cavas de mineração de areia na bacia hidrográfica do Paraíba do Sul e em Campo Grande – MS. O incremento de evaporação (0,9ND) aliado com o valor cobrado de R$ 0,02/m3 e a área alagada das cavas permitiram quantificar economicamente o valor do impacto. / The mining activity causes changes in the surface, which influence water loss to the atmosphere. Before installation of the pit mining, there is a natural water loss (evapotranspiration) of the surface. With the deepening of the pit, the area becomes a pond due to water upwelling in the pit from the aquifer, and evapotranspiration is changed to evaporation. The quantification of the change in water balance due to the pit is important to assess the impact of mining on groundwater reserves, and assist in licensing and degraded areas recovery programs for pits. This study aims: experimentally quantify the changes in the variables of the water balance; provide a predictive tool of evaporative losses for environmental licensing in mining pits and economically valuate the impact of that loss on groundwater reserves. For this, we used an experiment consisting of a drainage lysimeter with constant water table containing clay soil (lys-clay) and other sandy (lys-sand), an evaporation tank with constant water level buried in the ground, 20 m2 tank and the Penman-Monteith FAO-56. The monitoring of lysimeters was made for 56 months. Considering four-month periods and making the lysimeters water storage variation equal to zero, it is concluded that the evapotranspiration bahia grass in the lysimeters was less evaporation tanks and evapotranspiration estimated by the standard method of Penman-Monteith FAO-56. The vegetation coverage rate in the area of lysimeters in winter had lower rates, 50% of the evaporating surface, and estimate the net radiation adopted by the FAO-56 that overestimates the value are the causes. Evapotranspiration the lysimeter with sandy soil reaches a unitary relationship with the FAO-56 methodology when using it changes the way of estimating the net radiation, adopting the net radiation as 48% of global solar irradiance and only in the period from November to February (except March-June 2015). The drainage lysimeters with clay soil and sandy soil were very similar, and both were on average 50% of the rainfall. For environmental licensing phase mining pits 0.9ND the linear relationship being ND the number of days after the onset of the open water area in the pit, it can be used to predict water lost groundwater blade to the atmosphere. The above ratio was obtained in a grassy area with sandy soil and other free water in a humid tropical climate, with low water deficiency in the winter, with an average evapotranspiration of 3.3 mm/day. During the environmental licensing this methodology can predict impacts (evaporative losses) due to installation and increased mining pits. In degraded areas recovery programs the impact on underground water resources due to surface changes made during the mining activity can be quantified with this simple relationship (0.9ND). The method requires only the measurement area converted into free water surface, it can be used for satellite images and the above-described relationship. It was used the method in sand mining pits in the watershed of the Paraíba do Sul and city Campo Grande - MS. The increase evaporation (0.9ND) allied with the charge of R$ 0.02/ m3 and the area flooded the pits allowed economically quantify the value of impact.
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Construção, instalação e calibração de lisímetros para a determinação da evapotranspiração de referência na região do litoral de PernambucoLIMA, Nidielan da Silva 11 October 2012 (has links)
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Previous issue date: 2012-10-11 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Financiadora de Estudos e Projetos - Finep / Among the direct methods employed for estimating evapotranspiration lysimeters are more employees, as well as allow its direct determination, serve as instrument calibration and validation of empirical methods. This paper describes the procedures for construction, installation and calibration of two lysimeters in the experimental area in the coastal region of Pernambuco State, with tropical climate. Two lysimeters were built, the first drain and the second hydraulic weighing in an area completely surrounded by bahiagrass (Paspalum notatum) totaling 252 m². Lysimeter both, consist of an internal tank-type glass fiber with a water tank having circular edge area of 1,32 m² and a volume of 1 m³, being planted on the surface of the same program of the surrounding area. This tank is inserted into another, dug in the ground and walls of concrete and masonry. Lysimeters have a free drainage system, which is collected by the water level difference. The weighing system in the second lysimeter consists of three hydraulic pillows constructed with segments of flexible hose of butyl rubber nylon 100 mm in diameter, filled with water and interconnected by flexible tubes made of nylon, ending in the reading system composed of mercury column and sensing the hydrostatic pressure, which automates the readings lysimetric. The calibration of the weighing lysimeter consisted in the addition and removal of standard weights, equivalent to 1 mm layer of water at the same time sequences. This procedure was performed in the center and four quadrants of the lysimeter. The relationship between the difference of standard weights and the reading recorded in both the gauge and the sensor, were highly linear (R² in the range of 0,999) in all quadrants and the center of the weighing lysimeter. The average positional error in the manometer and the pressure sensor was 1,34 and 0,97%. This reflects high stability of readings even in situations of possible side slopes. The accuracy of the weighing lysimeter was 0,135 mm ETo registered by pressure gauge and up to 0,061 mm ETo registered in the pressure sensor, showing that the said sensor sensitive to variations in efficiency of the system mass lysimeter. / Dentre os métodos diretos empregados na estimativa da evapotranspiração os lisímetros são os mais empregados, pois além de permitirem a sua determinação direta, servem de instrumento de calibração e validação de métodos empíricos. O presente trabalho descreve os procedimentos de construção, instalação e calibração de dois lisímetros em área experimental na região do litoral do estado de Pernambuco, com clima tropical. Foram construídos dois lisímetros, o primeiro de drenagem e o segundo de pesagem hidráulica em uma área totalmente cercada de grama Batatais (Paspalum notatum) que totaliza 252 m². Ambos os lisímetros, são compostos de um tanque interno em fibra de vidro tipo caixa d’água com borda circular possuindo área de 1,32 m² e volume de 1 m³, sendo plantada na sua superfície a mesma grama da área circundante. Este tanque é inserido em outro, escavado no solo e com paredes de concreto e alvenaria. Os lisímetros possuem um sistema de drenagem livre, o qual a água é coletada por diferença de nível. O sistema de pesagem do segundo lisímetro, consiste de três travesseiros hidráulicos construídos com segmentos de mangueira flexível de borracha de butil-nylon de 100 mm de diâmetro, preenchidos com água e ligados entre si por tubos de nylon flexíveis, terminando no sistema de leitura composto por coluna de mercúrio e por sensor de pressão hidrostática, que automatiza as leituras lisimétricas. A calibração do lisímetro de pesagem consistiu na adição e retirada de pesos padrão, equivalente a 1 mm de lâmina de água, em sequências de tempo iguais. Este procedimento foi realizado na parte central e nos quatro quadrantes do lisímetro. A relação entre a diferença de pesos padrão e a leitura registrada tanto no manômetro quanto no sensor, foram altamente lineares (r² na faixa de 0,999) em todos os quadrantes e centro do lisímetro de pesagem. O erro médio posicional no manômetro e no sensor de pressão foi de 1,34 e 0,97 %. Isso reflete em alta estabilidade das leituras mesmo em situações de possíveis inclinações laterais. A precisão do lisímetro de pesagem foi de 0,135 mm de ETo registrado pelo manômetro e de até 0,061 mm de ETo registrado no sensor de pressão, mostrando que o sensor respondeu com eficiência a minúsculas variações de massa no sistema lisimétrico.
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Short-Term Water Use Dynamics in Drainage LysimetersDlamini, Musa V. 01 May 2003 (has links)
Turfgrass water use (seasonal turfET) and crop coefficients were determined and a mathematical soil-water balance model for non-weighing drainage lysimeters, which simulates the occurrence (timing and amount) of drainage, was developed. Pairs of non-weighing drainage lysimeters were used to determine crop coefficients for turfgrass in four locations in the state of Utah: Logan Golf and Country Club, Murray Golf Course, Brigham Young University (Spanish Fork) Experiment Farm, and Sunbrook Golf Course (St. George).
Daily weather data including air temperature, relative humidity, average wind travel, total solar radiation, precipitation, and average soil temperature were collected with an electronic weather station at each site. Daily precipitation was measured in three sites throughout the season: Murray, Spanish Fork, and Sunbrook. At Logan Golf and Country Club, precipitation was measured to November 10,2002.
Water use (averages of two lysimeters) during the growing season varied from 684 to 732 mm for three years (2000- 2002) for the mid-April through late-October observation period at Logan Golf Course; 699 mm for May through October at Murray; 469 mm at Spanish Fork; and 896 mm for late-February through early November at Sunbrook, for 2002 growing season. Calculated seasonal Etr using the 82 Kimberly Penman equation with a 1 00-miles-per-day wind travel limit varied from 1166 to 1229 mm at Logan Golf and Country Club, 1067 mm at Murray, 839 mm at Spanish Fork, and 1574 mm at Sunbrook. Seasonal Etr calculated using the PM ASCE std Etr equation was greater than the 82 Kimberly Peru11an . Seasonal Eto calculated using the FAO#56 Eto equation was less than both the 82 Kimberly Penman and the PM ASCE std Etr equations.
Calculated crop coefficients (as a ratio of measured crop water use and calculated potential evapotranspiration) based on alfalfa reference evapotranspiration with the 1982 Kimberly-Penman equation averaged 0.58 for the three years at Logan. Seasonal averages varied from 0.57 to 0.60. Seasonal crop coefficients (2002) were 0.57 for Logan, Spanish Fork, and Sunbrook, and 0.65 for Murray. Short-period crop coefficients also varied within a given season. Short-term crop coefficients derived from a time of wetting and drainage experiment averaged 0.55 at Logan, 0.56 at Murray, 0.60 at Spanish Fork, and 0.56 at Sunbrook.
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Microbial and Chemical Affects on Leachate from Calcareous Soils Treated with Wastewater EffluentPaul, Craig M. 06 July 2005 (has links) (PDF)
Increasing human populations are placing greater strain on water resources, prompting the use of treated wastewater effluent for irrigation in some areas, including the desert regions of the Western United States. To determine the potential effects of using secondary effluent for irrigation, we applied wastewater effluent and irrigation waters to natural and artificially constructed calcareous soils in greenhouse and field lysimeters, and in soil columns. The leachate from one field lysimeter contained increased fecal coliform counts than the effluent. Leachate coliform counts were decreased or not significantly changed in two field lysimeters. Electrical conductivity (EC), sodium adsorption ratio (SAR), chloride and nitrate concentrations also increased significantly in the leachate of the three field lysimeters however. Samples collected from the greenhouse lysimeters showed a significant decrease in all categories except EC, was not significantly changed. Soil column drainage samples showed a decrease in coliform counts, and increase in EC and chloride levels while SAR and nitrate levels varied with clay content. Preferential flow of coliform bacteria and high EC and SAR values could indicate long term effects that may affect the sustainability of the practice.
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Assessment of microbial health hazards associated with wastewater application to willow coppice, coniferous forest and wetland systems /Carlander, Anneli, January 2006 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2006. / Härtill 5 uppsatser.
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Effects of long- and short-term crop management on soil biological properties and nitrogen dynamicsStark, Christine January 2005 (has links)
To date, there has been little research into the role of microbial community structure in the functioning of the soil ecosystem and on the links between microbial biomass size, microbial activity and key soil processes that drive nutrient availability. The maintenance of structural and functional diversity of the soil microbial community is essential to ensure the sustainability of agricultural production systems. Soils of the same type with similar fertility that had been under long-term organic and conventional crop management in Canterbury, New Zealand, were selected to investigate relationships between microbial community composition, function and potential environmental impacts. The effects of different fertilisation strategies on soil biology and nitrogen (N) dynamics were investigated under field (farm site comparison), semi-controlled (lysimeter study) and controlled (incubation experiments) conditions by determining soil microbial biomass carbon (C) and N, enzyme activities (dehydrogenase, arginine deaminase, fluorescein diacetate hydrolysis), microbial community structure (denaturing gradient gel electrophoresis following PCR amplification of 16S and 18S rDNA fragments using selected primer sets) and N dynamics (mineralisation and leaching). The farm site comparison revealed distinct differences between the soils in microbial community structure, microbial biomass C (conventional > organic) and arginine deaminase activity (organic > conventional). In the lysimeter study, the soils were subjected to the same crop rotation (barley (Hordeum vulgare L.), maize (Zea mays L.), rape (Brassica napus L. ssp. oleifera (Moench)) plus a lupin green manure (Lupinus angustifolius L.) and two fertiliser regimes (following common organic and conventional practice). Soil biological properties, microbial community structure and mineral N leaching losses were determined over 2½ years. Differences in mineral leaching losses were not significant between treatments (total organic management: 24.2 kg N per ha; conventional management: 28.6 kg N per ha). Crop rotation and plant type had a larger influence on the microbial biomass, activity and community structure than fertilisation. Initial differences between soils decreased over time for most biological soil properties, while they persisted for the enzyme activities (e.g. dehydrogenase activity: 4.0 and 2.9 µg per g and h for organic and conventional management history, respectively). A lack of consistent positive links between enzyme activities and microbial biomass size indicated that similarly sized and structured microbial communities can express varying rates of activity.
In two successive incubation experiments, the soils were amended with different rates of a lupin green manure (4 or 8t dry matter per ha), and different forms of N at 100 kg per ha (urea and lupin) and incubated for 3 months. Samples were taken periodically, and in addition to soil biological properties and community structure, gross N mineralisation was determined. The form of N had a strong effect on microbial soil properties. Organic amendment resulted in a 2 to 5-fold increase in microbial biomass and enzyme activities, while microbial community structure was influenced by the addition or lack of C or N substrate. Correlation analyses suggested treatment-related differences in nutrient availability, microbial structural diversity (species richness or evenness) and physiological properties of the microbial community. The findings of this thesis showed that using green manures and crop rotations improved soil biology in both production systems, that no relationships existed between microbial structure, enzyme activities and N mineralisation, and that enzyme activities and microbial community structure are more closely associated with inherent soil and environmental factors, which makes them less useful as early indicators of changes in soil quality.
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Assessment of biogeochemical deposits in landfill leachate drainage systems phase IISaleh, Abdul R. Mulla 01 June 2006 (has links)
Land disposal of solid waste is a vital component of any solid waste management system. Design, operation and closure of municipal solid waste (MSW) landfills are required by regulations to control leachate and gases generated during the life, closure,and post-closure of the facility. Clogging of leachate drainage and removal systems in landfills is a common phenomenon and has been acknowledged in several landfills throughout the United States and abroad. This project was conducted in two phases. Phase I was completed in February of 2005 and Phase II was completed in August of 2006. Leachate characteristics data obtained in Phase I was processed and analyzed, along with supplementary data obtained in Phase II on liquid and solid phase testing. Leachate samples from the landfill and lysimeters indicated the presence of iron and sulfate-reducing bacteria. These bacteria are known to facilitate biologically induced precipitate formation.The mechanism by which biologically ind
uced precipitate may form begins with oxidizing acetate by iron and sulfate-reducing bacteria, reducing sulfate to sulfide and ferric iron to ferrous, and then forming calcium carbonate, iron sulfate, and possibly dolomite and other minerals.The results show that the clogging mechanism is driven by two major processes: transformation of volatile acids to substrates by iron and sulfate-reducing bacteria causing local pH and total carbonate to increase, which accelerate calcium carbonate precipitation, and thermodynamically favored reactions in supersaturated conditions based on saturation indices of calcium, sulfide, iron, and other species with respect to minerals. For each 1 mg of consumed volatile acids there were 1.7 mg of calcium, 0.28 mg of sulfate, and 0.03 mg of iron removed. Field and lysimeter precipitate samples were analyzed (using X-Ray Diffraction, Scanning Electron microscopy, and Electron Dispersive Spectroscopy) and correlated with geochemical modeling of leachate const
ituents. Precipitate analyses showed the presence of calcium carbonate, brushite (calcium phosphate),and dolomite, where as geochemical modeling showed that calcium carbonate, hydroxyapatite (complex of calcium phosphate), dolomite, pyrite, and siderite may be formed from field and lysimeter leachate constituents. The results also showed that submerged and stagnant conditions in the leachate collction systems accelerate the precipitation process.
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Nitrato na solução do solo e na água de fontes para consumo humano numa microbacia hidrográfica produtora de fumo / Nitrate in the soil solution and in the water of wells used for human consumption in a tobacco producing watershedKaiser, Douglas Rodrigo 24 November 2006 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The tobacco production system in Rio Grande do Sul state is mainly developed in small farms, using shallow soils in steep slope. In these areas rivers are born forming small
watersheds. The areas are fragilized by use of inappropriate tillage systems causing soil degradation. To compensate this, new areas are included in the production system, after
deforestation and not following environmental legislations rules. In order to maintain yield of the degraded areas is needed high fertilization rates and agrochemical application, following a technology package recommended by tobacco industry. Adding to this the fact, that tobacco has a low efficiency of nutrient use. The objective of this study, was monitored the nitrate concentration of soil solution in several soil management and use and in two domestic well used for drinking water. The study was carried out at Arroio Lino watershed, located in Nova Boemia district of Agudo county, state of Rio Grande do Sul. The area of the watershed presents high steepness and it prevails Entisols and mollisols.The soil solution was extracted with tension lysimeters equipped with ceramic porous cup installed at rooting depth (0,15 or 0,2 m) and below this depth (0,3 or 0,5 m), after the main rains happened during the tobacco cycle.The precipitation data were obtained from an automated
meteorological station installed at central part of watershed. In 2004/2005 agricultural year, the nitrate concentration was measured in lysimeters installed in a soil management experiment, in an Entisol, including tobacco no-tillage (NT), minimum tillage (MT) and conventional tillage (CT). In 2005/2006 agricultural year, the nitrate concentration was measured in five transects distributed in several places of the watershed, including tobacco plantation, forest and grass field. Two domestic wells located at lower position of landscape were monitored to nitrate concentration. One of those was located at a position which had above it 15 m stripe of forest and after had tobacco plantation, and the other had no tobacco plantation at position above it. At the points of each transect was evaluated bulk density, soil
porosity, saturated hydraulic conductivity and soil water retention curve. The soil tillage systems experiment showed higher value of nitrate concentration after starter fertilization application and decreased along of plant cycle, with content varying from 8 to 226 mg L-1. The highest concentration was observed at MT and lowest at NT. The average nitrate concentration in the rooting zone (0,2 m) was 75 for PD, 95 for MT and 49 mg L-1 for CT. Below the rooting zone, the average was 58 for NT, 108 for MT and 36 mg L-1 for CT. The soil in the transects presented low bulk density, low water storage, high porosity and high saturated hydraulic conductivity. The nitrate reached depths bellow rooting zone and its concentration was higher at tobacco plantation than at forest and grass field, reaching values as high as 80 mg L-1 in tobacco plantation. The well located below tobacco plantation had higher nitrate concentration, overcoming the critical limit of 10 mg L-1 in some periods. / A fumicultura no Rio Grande do Sul é desenvolvida em propriedades familiares em regiões ecologicamente frágeis, com solos rasos e alta declividade. Nessas regiões nascem rios e ocorre a formação de pequenas bacias hidrográficas. As áreas são fragilizadas por sistemas de manejo do solo impróprios para aquelas condições e, para manter a capacidade produtiva, recebem anualmente altas doses de fertilizantes e agrotóxicos, seguindo-se um pacote tecnológico difundido pelas agroindústrias fumageiras, que desconsidera as condições ambientais e os atributos do solo. O objetivo deste trabalho foi monitorar a concentração de nitrato na solução do solo, sob diferentes condições de uso e manejo, e na água de duas fontes usadas para o abastecimento doméstico, e relacioná-las com a influência antrópica. O estudo foi conduzido na microbacia hidrografia do Arroio Lino, localizada no distrito de Nova Boêmia, Agudo-RS. A área da microbacia apresenta alta declividade e nela predominam Neossolos e Chernossolos. A solução do solo foi extraída com lisímetros de tensão com cápsulas porosas na região da zona radicular do fumo (0,15 a 0,20 m) e abaixo dessa (0,30 a 0,50 m), logo após as principais chuvas ocorridas durante o ciclo do fumo. Os dados de precipitação foram obtidos de uma micro-estação meteorológica
automatizada instalada na microbacia. Na safra de 2004/2005, os lisímetros foram instalados num experimento, sob Neossolo Litólico, com sistemas de manejo para a implantação da cultura do fumo, sendo monitorado o sistema plantio direto (PD), cultivo mínimo (CM) e preparo convencional (PC). Na safra de 2005/2006, os lisímetros foram instalados em cinco transeções distribuídos na paisagem, abrangendo lavouras de fumo, mata e campo nativo. As duas fontes monitoradas estavam localizadas na encosta, sendo que uma delas apresentava uma faixa de 15 m de mata na sua volta e, acima dessa, era cultivado fumo. A outra fonte estava protegida pela mata e não apresentava influência antrópica nas suas proximidades. Nos pontos de cada transeção, avaliaram-se a densidade do solo, porosidade do solo, condutividade hidráulica saturada e curva de retenção de água. Nos sistemas de manejo do solo os teores de nitrato variaram de 8 a 226 mg L-1 e foram maiores após a adubação de base e decresceram ao longo do ciclo. Os níveis mais altos foram obtidos no CM e os menores no PD. Os teores médios de nitrato na zona radicular foram de 75 no PD, 95 no CM e 49 mg L-1 no PC. Abaixo da zona radicular os teores médios
foram de 58 no PD, 108 no CM e 36 mg L-1 de nitrato no PC. O solo nas transeções apresentou baixa densidade, baixa capacidade de armazenamento de água, alta porosidade
e alta condutividade hidráulica saturada. O nitrato atingiu profundidades abaixo da zona de exploração radicular (0,5m). Os teores de nitrato foram superiores nas lavouras em relação
ao campo e à mata nativa, atingindo 80 mg L-1 nas áreas com fumo. A fonte (poço) que se encontrava abaixo das lavouras de fumo teve maiores concentrações de nitrato, superando o limite crítico de 10 mg L-1 em alguns períodos.
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