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Consumo de água e perdas de nutrientes e de sedimentos na água de drenagem inicial do arroz irrigado
Machado Sérgio Luiz de Oliveira,Marchezan Enio,Righes Afranio Almir,Carlesso Reimar
Ciência Rural , 2006,
Abstract: No Rio Grande do Sul (Brasil), a lavoura arrozeira é grande consumidora de água e apresenta potencial de contamina o de mananciais hídricos quando a drenagem inicial é realizada. Este trabalho teve como objetivo quantificar o consumo de água do arroz irrigado submetido a sistemas de cultivo (Experimento I) bem como verificar a concentra o de nutrientes e de sedimentos em suspens o na água de drenagem inicial no pré-germinado, mix de pré-germinado e transplante de mudas (Experimento II). Os experimentos foram conduzidos em 2000/01 e 2001/02 (Experimento I) e 1999/00, 2000/01 e 2001/02 (Experimento II) em área de várzea em Planossolo Hidromórfico Eutrófico, arênico na Universidade Federal de Santa Maria (UFSM), Santa Maria (RS). No experimento I, o consumo de água no sistema convencional, cultivo mínimo, pré-germinado, mix de pré-germinado e transplante de mudas foi analisado no delineamento experimental em blocos ao acaso, com quatro repeti es. O consumo de água n o foi afetado pelos sistemas de cultivo variando de 5.431 a 6.422 e de 5.374 a 5.852m3 ha-1, respectivamente para 2000/01 e 2001/02. A quantidade de água necessária para o preparo inicial do solo no pré-germinado e transplante de mudas ou para a forma o da lamina d?água no mix de pré-germinado foi de 1.285m3 ha-1. No experimento II, os três anos agrícolas (1999/00, 2000/01 e 2001/02) com os três sistemas de cultivo (pré-germinado, mix de pré-germinado e transplante de mudas) foram comparados para quantificar as perdas de nutrientes e de sedimentos na água de drenagem inicial. As concentra es de nitrato, fósforo e magnésio na água foram similares entre os sistemas de cultivo. No mix de pré-germinado, a concentra o de am nio e potássio foram maiores que no pré-germinado e transplante de mudas, com 3,85 e 7,70mg L-1 respectivamente. Contudo as perdas de nutrientes verificadas estiveram dentro de limites aceitáveis de acordo com a legisla o vigente. A turbidez e a presen a de sedimentos na água de drenagem inicial foi menor no mix de pré-germinado em compara o com o pré-germinado e transplante de mudas, indicando que a manuten o da água na lavoura nestes sistemas de cultivo é importante para sustentabilidade do ecossistema arroz irrigado e manuten o do potencial produtivo da cultura.
Consumo de água e perdas de nutrientes e de sedimentos na água de drenagem inicial do arroz irrigado
Machado, Sérgio Luiz de Oliveira;Marchezan, Enio;Righes, Afranio Almir;Carlesso, Reimar;Villa, Silvio Carlos Cazarrotto;Camargo, Edinalvo Rabaiolli;
Ciência Rural , 2006, DOI: 10.1590/S0103-84782006000100010
Abstract: in rio grande do sul, brazil, irrigated rice fields use large amount of water and have the potential of contaminate surface water bodies when drainage is performed. the objective of this experiment was to quantify the amount of water in flooded rice fields under different cropping systems (experiment i) and to measure the concentration of nutrients in the initial drainage water of pre-germinated, pre-germinated mix and seedling transplanting systems (experiment ii). the research was conducted during 2000/01 and 2001/02 (experiment i) and during 1999/00, 2000/01 and 2001/02 (experiment ii) in a lowland area of a planosoil located at the federal university of santa maria-rs, brazil. in the years 2000/01 and 2001/02 (experiment i) five cropping systems (conventional, minimum tillage, pre-germinated, mix of pre-germinated and seedling transplanting) randomized block experimental design with four replications were used. the cropping systems did not influence the use of water by flooded rice, varying from 5,431 to 6,422 and 5,347 to 5,852m3 ha-1 for the years 2000/01 and 2001/02, respectively. the amount of water used for flooding the soil in the pre-germinated and seedling transplanting systems or form stablishing a layer of water in the mix pre-germinated was 1,285m3 ha-1. in experiment ii, three cropping systems (pre-germinated, mix of pre-germinated and seedling transplanting) were compared. nitrate, phosphorus and magnesium concentrations in the initial drainage water were similar in the different cropping systems. in the mix of pre-germinated system, ammonium and potassium concentrations were higher when compared with the pre-germinated and seedling transplanting systems with averages of 3.85 and 7.70mg l-1, respectively. recorded nutrient losses were within the range allowed by the currente legislation. the concentration of sediments in the drainage water was lower in the mix of pre-germinated system when compared to pre-germinated and seedling transplanting system
Water infiltration and time to recharge the profile of three soils Rio Grande do Sul, Brazil  [PDF]
Afranio Almir Righes, Galileo Adeli Buriol, Valduino Estefanel
Agricultural Sciences (AS) , 2013, DOI: 10.4236/as.2013.411A002
Abstract:

The Rio Grande do Sul-RS State, even with average annual rainfall of 1.721 mm, has shown a lack of water in the soil for crop production. The study aimed to determine the variation of annual and seasonal precipitation over the time; determine the year seasons that can provide the recharge of water into the soil profile and estimate the time needed to fulfill the soil pore space with water from effective rainfall with different scenarios of water infiltration. The soil uses were: oxisol; Red Yellow Podzolic and Planosolo Hydromorphic Eutrophic respectively in the North, Centre and South of RS State. We determined the total variation of annual rainfall, mean annual potential evapotranspiration and the time required to refill the soil profile for three infiltration scenarios: with fractions 1/2, 2/3 and 3/4 of effective rainfall. In the regions of Passo Fundo, Santa Maria and Santa Vitóriado Palmar, from 1914 to 2004 there was no reduction in the annual volume of rainfall. Considering that 50% of soil volume and water storage are met and that the fraction 1/2, 2/3 and 3/4 of the effective rainfall infiltrates into the soil, the recharging time profile varies from 3.7 to 16.6 years, infiltrating 2/3 range from 1.8 to 6.6 years and infiltrating 3/4 of effective precipitation range from 1.2 to 5.1 years, the time required to refill the entire soil porous space. The recovery of water storage in the soil profile must occur mainly during winter, followed by spring and fall.

Vertical Mulching e manejo da água em semeadura direta
Garcia, Sandra Maria;Righes, Afranio Almir;
Revista Brasileira de Ciência do Solo , 2008, DOI: 10.1590/S0100-06832008000200037
Abstract: intensive soil mobilization in the conventional tillage system has caused soil structure degradation, soil compaction below the arable layer, and decreased macroporosity. these changes resulted in reduced soil water infiltration rate and increased runoff, soil erosion and sedimentation in rivers and reservoirs. in the no tillage system the water erosion from the soil surface is practically controlled, and the terraces were eliminated by the farmers. nevertheless, the surface flow is higher than it was in the conventional tillage system. with the objective of evaluating the hydrological behavior of vertical mulching in no tillage systems as related to runoff, this study was developed in the growing seasons of 2002/2003 and 2003/2004 on a red latosol (oxisol) in the planalto médio region of rio grande do sul state, brazil. a field experiment was installed using plots without vertical mulching, with vertical mulching at every 10 m and with vertical mulching at every 5 m. it was used a randomized block design with three replications. leveled furrows of vertical mulching, perpendicular to the soil slope (0.08 m wide by 0.38 m deep) were dug and filled with straw compacted enough to stabilize the furrow sides. rainfall intensities of 70 and 106 mm h-1 were simulated on soybean and wheat to determine runoff, soil water infiltration rate, and nutrient and organic carbon concentration in the runoff. the results showed that vertical mulching in no tillage significantly reduces surface runoff and increases the water infiltration rate into the soil. it also reduces the total nutrient and organic carbon losses due to the reduction of water runoff.
Rendimento do arroz e manejo da irriga??o e da palha de azevém no sistema mix de pré-germinado
Pinto, Eduardo González;Righes, Afranio Almir;Marchezan, Enio;
Ciência Rural , 2003, DOI: 10.1590/S0103-84782003000200008
Abstract: the incidence of red rice on flooded rice production is a limiting factor in many agricultural areas, when high productivity is the objective. alternative system of crop cultivation using no tillage on flooded water seed system can be used to minimize the problem. although this system has technical and economical advantages on the production chain, especially on red rice control, anaerobic process of ryegrass straw decomposition may produce toxic substances to rice plants establishment. the objective of this work was to evaluate the effect of different water irrigation management and the amount of ryegrass straw on grain yield and yield components on paddy rice cultivated. the experiment was conducted in greenhouse, during the 1998/99 crop growing season, on hidromorphy planosoil, sandy eutrophic, soil mapping unit "vacacaí", over ryegrass crop residue at the federal university of santa maria, santa maria, rs. the rice cultivar irga 417 was used. a completely randomized design factorial (3x3), three water management (with neither vertical nor surface in-out water flow over the soil, with drainage and surface water flow) and three amount of ryegrass straw (0.0 t ha-1, 3.43 t ha-1 and 6.86 t ha-1). the data demonstrated that a permanent flooding with neither vertical nor surface in-out water flow reduce dry matter above ground and grain yield when compared to the treatments with drainage and surface in-out water flow. increasing the amount of ryegrass straw on the no-tillage water seed system, with neither vertical nor surface in-out water flow, on the flooded water the grain yield is reduced.
Tratamento do lixiviado de aterro de resíduos sólidos urbanos por processo Fenton
Victor Wegner Maus,Adilson Ben da Costa,Afranio Almir Righes
Tecno-Lógica , 2009,
Abstract: O lixiviado gerado em aterros sanitários pela decomposi o dos resíduos sólidos com presen a de água de infiltra o possuigrande potencial poluidor, devido à elevada concentra o de substancias tóxicas e a sua baixa biodegradabilidade. A coagula oquímica pode ser uma alternativa para o tratamento de efluentes com essas características. O trabalho teve como objetivo avaliar aeficiência do processo Fenton no tratamento de lixiviado gerado em aterros sanitários de resíduos sólidos urbanos. As amostras delixiviado foram coletadas no aterro controlado do município de Santa Maria – RS. No experimento foram testados cincotratamentos com diferentes propor es de reagentes (H2O2 e FeSO4) TH2O2/FeSO4: T0,8, T2,0, T3,0, T4,0 e T6,0. Pelos resultados doexperimento com processo Fenton verifica-se uma eficiência média na remo o da demanda química de oxigênio (DQO) de47,9%, na turbidez de 53,0% e na cor de 70,7%. Os valores médios da demanda bioquímica de oxigênio (DBO) e dacondutividade elétrica aumentaram em 31,3% e 27,1%, respectivamente. No tratamento T0,8 constatou-se a maior remo o daDQO e o maior aumento da biodegradabilidade. O processo Fenton aplicado no tratamento de lixiviado reduz a DQO e aumenta aDBO, em outras palavras, aumenta a biodegradabilidade do efluente. Esse processo pode ser utilizado como pré-tratamento de umsistema biológico para efluentes de aterros sanitários. Abstract The leachate generated on sanitary landfill bysolid waste decomposition with rainfall water infiltration hashigh potential of pollution, due to high concentration oftoxic substances and low biodegradability. The chemistrycoagulation can be an alternative to treat effluents with thesecharacteristics. The work aimed to evaluate the efficiency ofFenton process in the treatment of leachate landfill fromurban solid waste. The leachate samples were collected fromthe controlled landfill of Santa Maria Council – RS. In theexperiment were tested five treatments with differentproportions of reagents (H2O2 e FeSO4) TH2O2/FeSO4: T0,8,T2,0, T3,0, T4,0 and T6,0. The experimental data with Fentonprocess showed an average removing efficiency on chemicaloxygen demand (COD) of 47.9%, on the turbidity 53.0%and 70.7% for color. The average values of biochemicaloxygen demand (BOD) and electric conductivity increasedon 31.3% and 27.1%, respectively. On the leachate treatmentwith T0,8 notes the largest removal COD and higher increase biodegradability. The Fenton process applied to leachatetreatment reduces the COD and increases the BOD, in theother words, increase the effluent biodegradability. T
Manejo da palha de azevém, da aduba o de base e da água de drenagem na produ o de arroz irrigado
Swarowsky Alexandre,Righes Afranio Almir,Marchezan Enio,Rhoden Anderson Clayton
Ciência Rural , 2004,
Abstract: Sistemas com mínimo revolvimento do solo s o favoráveis ao controle de plantas daninhas, à utiliza o mais intensiva dos solos de várzea e à rentabilidade do orizicultor, mas apresentam algumas limita es, como a produ o de substancias que podem ser tóxicas ao arroz, bem como altera es na disponibilidade de nutrientes em ambientes alagados. O trabalho teve como objetivo comparar diferentes sistemas de manejo da palha de azevém, da aduba o de base, e da drenagem, no rendimento de gr os de arroz e nos componentes da produ o. O experimento foi conduzido na Universidade Federal de Santa Maria. Foram avaliados três níveis de manejo da resteva de azevém (planta de azevém em pé, planta de azevém incorporada e sem a planta de azevém), três condi es de aduba o (sem aduba o, aduba o do arroz 100% aplicada na semeadura do azevém e aduba o do arroz 100% aplicada na semeadura do arroz) e dois manejos da água de drenagem (inunda o convencional em condi es de campo e inunda o sem drenagem). Os resultados obtidos permitem concluir que, na cultura do arroz irrigado por inunda o, a incorpora o da palha de azevém e a aplica o da aduba o para o arroz na semeadura do azevém n o afetam o rendimento de gr os e os componentes da produ o. Entretanto, a ausência de drenagem interna no solo reduz o rendimento de gr os de arroz, o número de panículas e o número de gr os por panícula.
Rendimento do arroz e manejo da irriga o e da palha de azevém no sistema mix de pré-germinado
Pinto Eduardo González,Righes Afranio Almir,Marchezan Enio
Ciência Rural , 2003,
Abstract: A incidência de arroz vermelho na cultura do arroz irrigado tem praticamente inviabilizado o cultivo em muitas áreas do Rio Grande do Sul, destacando-se como um dos principais entraves ao aumento da produtividade. Uma alternativa para minimizar o problema é o sistema mix de pré-germinado, que consiste em utilizar sementes pré-germinadas, em área com vegeta o dessecada e previamente inundada. O sistema apresenta vantagens técnicas e econ micas na cadeia de produ o. Entretanto, a decomposi o anaeróbia da palha presente na área, após o alagamento, pode provocar a forma o de substancias tóxicas afetando o estabelecimento das plantulas. Este trabalho teve como objetivo determinar o efeito do manejo da água de irriga o e das quantidades de palha de azevém no rendimento de gr os e componentes de produ o do arroz irrigado no sistema mix de pré-germinado. O experimento foi conduzido em casa de vegeta o, no ano agrícola 1998/99, em PLANOSSOLO HIDROMóRFICO Eutrófico arênico, pertencente à unidade de mapeamento Vacacaí, na Universidade Federal de Santa Maria, em Santa Maria. - RS, utilizando-se a cultivar IRGA 417, em resteva de azevém. Os tratamentos foram avaliados em delineamento inteiramente casualizado, no arranjo fatorial (3x3), com dois fatores: (i) manejo da água em três níveis (lamina estagnada, com drenagem e com fluxo de superfície) e (ii) palha de azevém em três quantidades (0,00 t ha-1, 3,43 t ha-1 e 6,86 t ha-1). Os resultados evidenciam que, no sistema mix de pré-germinado, mantendo-se uma lamina estagnada sobre o solo, reduz-se a massa seca total e o rendimento de gr os de arroz em rela o ao manejo da água com drenagem e com fluxo de superfície. O aumento na quantidade de palha de azevém na cultura do arroz no sistema de cultivo mix de pré-germinado, sem fluxo de água em superfície ou drenagem, reduz o rendimento de gr os.
Manejo da palha de azevém, da aduba??o de base e da água de drenagem na produ??o de arroz irrigado
Swarowsky, Alexandre;Righes, Afranio Almir;Marchezan, Enio;Rhoden, Anderson Clayton;Gubiani, Ezio Itamar;
Ciência Rural , 2004, DOI: 10.1590/S0103-84782004000200009
Abstract: cultivation systems with minimum tillage are used to minimize red rice incidence, improving crop yield and the agricultural exploration of lowland soils. however, some limitations are present such as toxic substances due to anaerobic straw decomposition (prejudicial to rice plant establishment), as well as alterations on some available nutrients under flooded soil water conditions. the objective of this work was to compare different drainage systems; ryegrass straw management and time of fertilizer application on yield and yield components of rice plants. the experiment was conducted at the federal university of santa maria, rio grande do sul state-brazil. three ryegrass straw levels (no-tillage with ryegrass were evaluated, ryegrass plant incorporated with rotary tilling and without ryegrass plant), three fertilization conditions (without fertilizer; fertilizer applied at the ryegrass sowing time and fertilizer applied at rice sowing time) and two drainage management (conventional flooded and flooded without drainage). results demonstrated that yield and yield components of rice production was not affected by fertilizer application at ryegrass sowing or at rice sowing. meanwhile, deep-water drainage suppression reduces the grain yield and yield components.
Sand Filter for Rainfall Water with Reverse Flow
Hilton Ruoso Junior,Pedro Daniel da Cunha Kemerich,Afranio Almir Righes
Engenharia Ambiental : Pesquisa e Tecnologia , 2010,
Abstract: The use of drinking water in activities that require no potable water is a waste of resources that could be avoided by using clean water, as the rainfall water. This procedure saves the amount spend on toilet discharges in washing cars, sidewalks, clothes and general irrigation as well as on the reduction of floods, helping to minimize environmental impacts on urban areas. This work aims to design, develop and test a sand filter to retain solid waste material from the rain water, allowing the improvement of their quality. The experimental work was developed in the laboratory of Environmental Engineering at the “Centro Universitário Franciscano”, using sand as a filter for a water reservoir of 250 liters, with filter materials such as gravel, sand, and geotextil and a electrical water-pump to test the system of reverse flow. By the results obtained the maximum flow filtration rate estimated is 11,800 L h-1. The filter controls 100% of particles larger than 0.15 mm. Filtered water in 75% of particles not removed by the filter has diameter less than 0.075 mm. The filter also provides efficiency of 79.12% in the removal of turbidity, 77.04% of color, electrical conductivity and 55.86% in 85.96% of total solids.
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