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EFECTOS HIDROAMBIENTALES DE LA EXTRACCIÓN DE AGUA DEL ACUÍFERO DEL RÍO SINALOA | Hydro-environmental effects of the extraction of water from the Sinaloa River Aquifer Full text
2011
OMAR LLANES CARDENAS | MARIANO NORZAGARAY CAMPOS | YOLANDA LOURDES MAYA DELGADO | NORMA PATRICIA MUÑOZ SEVILLA | ENRIQUE TROYO DIEGUEZ | Bernardo Murillo Amador | Félix Alfredo Beltrán Morales
" La llanura costera del acuífero del Río Sinaloa es vulnerable a la contaminación antropogénica y natural. Dicho impacto es exacerbado por la condición somera de las aguas subterráneas (0.1 a 9.2 m) y la elevada evapotranspiración (834.32 mm año−1), no balanceada por la precipitación promedio anual (577.9 mm año−1). Por lo anterior, los objetivos de este trabajo fueron: (1) determinar la vulnerabilidad del acuífero a la contaminación costera y (2) estimar la vulnerabilidad debida a las actividades antropogénicas, en función del aporte del flujo subterráneo. Se aplicó el método estandarizado DRASTIC a una escala 1:10 000 y se determinó la piezometría de la región mediante la información de 155 pozos. Se registraron la profundidad del nivel freático (D), la recarga neta (R), el material del acuífero (A), el tipo de suelo (S), la cota y pendiente del terreno (T), el impacto de la zona no saturada (I), la conductividad hidráulica (C) y la altura de la superficie piezométrica, y se calculó la carga hidráulica. Los resultados muestran una vulnerabilidad valorada de insignificante (Vi) a alta (Va), con un intervalo de variación de 88 a 166 unidades, amortiguada cuando la fuerza del flujo es alta y acentuada cuando la misma amengua. La costa y zona oeste fueron las más vulnerables, con 35 y 8%, e índices de 140 a 166 y 139 a 157. Los altos índices DRASTIC se atribuyeron a la acumulación de solutos arrastrados hacia la costa por un flujo regional y otro intermedio, que atrapan a los mismos en pequeñas cuencas de escaso espesor. " | " The coastal plain of the Sinaloa River aquifer is vulnerable to anthropogenic and natural pollution. Impacts are increased by the shallowness of the groundwaters (0.1 to 9.2 m) and a high evapotranspiration (834.32 mm year−1) that is not balanced by the annual average rainfall (577.9 mm year−1). According to this scenario, the objectives of this study were: (1) to determine the vulnerability of the aquifer in face of coastal pollution and (2) to estimate the vulnerability as a function of groundwater flow, resulting from anthropogenic activities. The standardized DRASTIC INDEX method was applied at a 1:10 000 scale and the piezometry of the region was determined through the information recorded for 155 wells. The parameters recorded were the depth of the water table (D), the net recharge (R), the aquifer material media (A), the soil type (S), the topography and slope of the land (T), the impact on the unsaturated zone (I), the hydraulic conductivity (C) and the height of the piezometric surface, and the hydraulic head was calculated. The results indicate a vulnerability that varies from insignificant (Vi) to high (Va), with a variation range of 88 to 166 units, mitigated when the force of the aquifer flow is high and accentuated when it is reduced. The coast and the western area were the most vulnerable, with 35 and 8%, and indices of 140 to 166 and 139 to 157. The high DRASTIC indices were attributed to the accumulation of solutes that are transported to the coast by a regional flow and an intermediate flow, which trap them in small basins of reduced thickness. "
Show more [+] Less [-]Água salina nos atributos químicos do solo e no estado nutricional da mandioqueira Saline water on chemical properties of soil and nutritional status of Cassava Full text
2011
Roberto S. F. de Holanda Filho | Delfran B. dos Santos | Carlos A. V. de Azevedo | Eugênio F. Coelho | Vera L. A. de Lima
O objetivo do presente trabalho foi verificar a influência do uso de água salina nos atributos químicos do solo e no estado nutricional da mandioqueira. O trabalho foi conduzido na área experimental de Irrigação e Drenagem do IF Baiano, Campus de Senhor do Bonfim, BA (10o 28’S, 40o 11’W e 550 m). O delineamento experimental utilizado foi o inteiramente casualizado constando de sete tratamentos e três repetições. Os tratamentos consistiram de uma testemunha (sequeiro), um tratamento irrigado com água potável (100% da ETc) e cinco tratamentos irrigados com água salina com CE de 3 dS m-1 variando as lâminas aplicadas: 110, 120, 130, 140 e 150% da ETc. O uso de água salina aumentou a percentagem de sódio trocável, a razão de adsorção de sódio e a condutividade elétrica do solo, tanto na 0-0,20 como na 0,20-0,40 m de profundidade. Quanto ao estado nutricional foliar da mandioqueira, os tratamentos influenciaram apenas nos teores de cálcio, magnésio e cloro.<br>The purpose of this study was to assess the influence of saline water on chemical properties of the soil and nutritional attributes of cassava. The work was conducted in the area of Irrigation and Drainage of IF Baiano, Campus de Senhor do Bonfim, BA (10° 28’S, 40° 11’W and 550 m). The experimental design was completely randomized, consisting of seven treatments and three replicates. The treatments consisted of control (rainfed), a treatment irrigated with drinking water (100% of ETc) and five treatments irrigated with saline water of 3 dS m-1 with varying water depths: 110, 120, 130, 140 and 150% of ETc. The use of saline water increased the exchangeable sodium percentage, the sodium adsortion ratio and the electrical conductivity of the soil in both 0-0.20 and 0.20-0.40 m dephts. Regarding the leaf nutritional status of cassava, the treatments influenced only the contents of calcium, magnesium and chlorine.
Show more [+] Less [-]AN ASSESSMENT OF WATER QUALITY (NH4+, NO2-, NO3-, TP, SO4, COLIFORM BACTERIA AND HEAVY METALS) OF THE MAIN WATER SUPPLIES IN THE STATE OF CAMPECHE | DIAGNÓSTICO DE LA CALIDAD DEL AGUA (NH4+, NO2-, NO3-, TP, SO4, BACTERIAS COLIFORMES Y METALES PESADOS) DE LAS PRINCIPALES FUENTES DE ABASTECIMIENTO DE AGUA EN EL ESTADO DE CAMPECHE Full text
2011
Benitez, Jorge Arturo | Lara-Flores, Maurilio | Osorio, Victor Manuel | Amabilis, Leonel | Ben-Arie, Joshua | Rendon, Jaime | Vidal-Maldonado, Jimmy | Cen-Poot, Brenda Trinidad | Sonda-Santos, Karina | COMISION NACIONAL DEL AGUA, GOBIERNO DEL ESTADO DE CAMPECHE
Water quality testing (in situ and in laboratory) was conducted on 50 wells across the state of Campeche. Further to this (to aid in water quality management and policy), a GIS was implemented to i) approximate Zones of Contribution (ZOC) for well recharge which in turn supplies water for main cities in the state and ii) perform predictive land change modeling on these ZOC’s to predict the future effect of non-point source pollution. Due to natural geohydrological conditions, values of TDS, pH, and SO4 exceeded Mexican regulations in roughly one third of the wells. Although most wells do not exceed the permissible limits of nutrients and heavy metals, some wells show worryingly high levels of NO2-, TP, and Pb, indicators of pollution from anthropogenic sources. All wells were contaminated by coliform bacteria. Poor water quality in some of the main water sources in the state is mainly due to the proliferation of open dumps and the lack of sewage infrastructure, as well as the ongoing conversion of vegetated land to agriculture into the ZOC’s. It is shown that unless remedial measures are implemented, human activities will continue to extend into these areas, placing the state’s water supply at even higher risk of contamination. | Se analizó la calidad del agua (in situ y laboratorio) de 50 pozos en todo el Estado. Además, se implemento un SIG (para establecer polÃticas y pautas de manejo de la calidad del agua), consistente en i) delimitar de manera preliminar la zona que contribuye agua a los pozos (ZOC) que abastecen las principales ciudades y ii) modelar las tendencias del uso del suelo para predecir el efecto futuro de las fuentes dispersas de contaminación. Debido a condiciones naturales geohidrológicas, los valores de STD, pH y SO4 rebasaron los lÃmites permisibles de la normatividad mexicana en alrededor de un tercio de los pozos. Aunque la mayorÃa de los sitos no excedieron los lÃmites permisibles para nutrientes y metales pesados, algunos pozos mostraron niveles de NO2-, TP, SO4, y Pb preocupantemente altos, lo cual es un indicador de contaminación antropogénica. Todos los pozos presentaron contaminación por bacterias coliformes. La baja calidad del agua en algunas de las principales fuentes de abastecimiento del Estado se debe principalmente a la proliferación de basureros a cielo abierto y la deficiente red de alcantarillado, asà como al cambio de uso del suelo dentro de la ZOC. Si no se implementan las medidas adecuadas, las actividades humanas continuaran extendiéndose dentro de estas áreas colocando a las fuentes de agua en un mayor riesgo de ser contaminadas.Â
Show more [+] Less [-]EVALUACIÓN DE LA CINÉTICA DE LA ACUMULACIÓN DE CROMO EN EL BUCHÓN DE AGUA (Eichhornia crassipes) AVALIAÇÃO DA CINÉTICA DE ACUMULAÇÃO DE CROMO EM JACINTO DE AGUA (Eichhornia crassipes) EVALUATION OF THE KINETICS OF ACCUMULATION OF CHROMIUM IN WATER HYACINTH (Eichhornia crassipes) Full text
2011
RICARDO BENÍTEZ | VÍCTOR CALERO | ENRIQUE PEÑA | JAIME MARTÍN
Eichhornia crassipes es una planta de rápido crecimiento distribuida en casi todos los países tropicales, que puede tolerar condiciones de contaminación por metales o por eutrificación de cuerpos de aguas lénticos y lóticos. Esta planta se ha convertido en un problema ambiental; no obstante, ha despertado interés en el tratamiento de la contaminación por metales en suelos agrarios y cuerpos de agua. La toxicidad de los metales es un serio inconveniente en esta motivación, ya que influye en la capacidad de acumulación y la transmisión en la cadena trófica. En esta investigación se evaluó el comportamiento de las tasas de acumulación de cromo en la macrófita acuática Eichhornia crassipes, a concentraciones de 30, 60 y 90 mg/L, utilizando un diseño experimental aleatorio, con control y tres repeticiones por nivel. Los estudios llevados a cabo en acuarios de vidrio, evidenciaron sitios de acumulación de cromo en la planta, estableciéndose la cinética de acumulación.<br>Eichhornia crassipes é uma planta de rápido crescimento distribuídas em quase todos os países tropicais, que podem tolerar condições de contaminação por metáis ou de eutrofização das massas de águas lênticos e lóticos. Essa planta tornou-se um problema ambiental, no entanto, despertou o interesse no tratamento da poluição por metais em solos agrícolas e corpos d'água. A toxicidade dos metais é um problema serio com esse raciocínio, uma vez que afeta a capacidade de armazenamento e transmissão na cadeia alimentar. Neste estudo avaliou o comportamento das taxas de acúmulo de cromo em macrófitas aquáticas Eichhornia crassipes, em concentrações de 30, 60 e 90 mg/L, utilizando um delineamento inteiramente casualizado, com controle e três repetições por nível. Estudos realizados em aquários de vidro, apresentaram sítios de acumulação de crómio na planta, que institui a cinética de acumulação.<br>Eichhornia crassipes is a fast growing plant distributed in almost all tropical countries, which can tolerate conditions of metal contamination or eutrophication of bodies of lentic and lotic waters. This plant has become an environmental problem, however, has sparked interest in the treatment of metal pollution in agricultural soils and water bodies. The toxicity of metals is a serious problem with this reasoning, since it affects the storage capacity and transmission into the food chain. In this study we evaluated the behavior of the rates of accumulation of chromium in aquatic macrophyte Eichhornia crassipes, at concentrations of 30, 60 and 90 mg/L, using a randomized experimental design with control and three replicates per level. Studies carried out in glass aquaria, showed sites of accumulation of chromium in the plant, establishing the kinetics of accumulation.
Show more [+] Less [-]Custos de disponibilização e disposição a pagar pela água de rega: metodologia de análise | Costs of delivery and willingness to pay for irrigation water: methodology Full text
2011
Avillez, Francisco | Silva, Francisco Gomes da
Sustainable use of water resources should include the recognition that water has a social value, an environmental value and an economic value. The economic value of irrigation water should be expressed based on its price, which in turn is determined by the interplay of three factors: the cost of irrigation water (supply side), the willingness to pay for irrigation water (demand side) and public policies. This paper presents an analysis of the key methodological issues involved ineach of the above mentioned factors and how they influence the economic value of water
Show more [+] Less [-]Adaptação de equipamento de geração de gases oxidantes para aplicação na desinfecção de água | Adaptation of generator oxidant gases equipament to aplication in water disinfection Full text
2011 | 2009
Oliveira, Silvestre Zechinelli de | Tinôco, Adelson Luiz Araújo | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4787553U8 | Borges, Alisson Carraro | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4706302U9 | Souza, Cecília de Fátima | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4784862P9 | Tinôco, Ilda de Fátima Ferreira | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4783628D6 | Nascimento, José Wallace Barbosa do | http://lattes.cnpq.br/9274991135144621 | Rezende, Ana Augusta Passos | http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4786153D5
Human consumption of water outside of the microbiological standards for drinking constitutes a health and disease risk factor. Through the process of infiltration in the soil, groundwater may be contaminated by the waste generated by human activity and deposited in the soil, waterways or air. The consumption of water in natura, captured in a spring, may lead to the risk of disease. One of the alternative technologies for disinfecting water that has shown promise is the generation of an oxidant solution in loco. The electrochemical reaction of sodium chloride produces oxidizing gases, which reacts with the water to produce the hypochlorite ion in balance with hypochlorous acid, along with traces of other oxidants. In the present study the development of a device based on an imported model that uses this type of technology wassought in order to reduce the cost of acquisition and makeit more available to disadvantaged communities with water quality issues. The evaluation of the efficiency of this technology in disinfecting water with different qualities (color and turbidity) was also sought, using total coliforms and Escherichia coli as indicator organisms of contamination. In each experimentthe quality of untreated water, and water after adding the oxidant was examined on turbidity, true color, residual chlorine, pH, temperature, and quantification of microorganism indicators. In the experiments performed we found that the adapted equipment showed to be as efficient in the production of disinfectant agents as the original equipment. In the microbiological assays performed on water contaminated with E. coli (synthesized water in a laboratory and natural) and total coliforms (natural water), the inactivation of these organisms was observed to be effective with the use of gases that came from the adapted equipment, taking into account the content of chlorine in water treated with the equipment. | Human consumption of water outside of the microbiological standards for drinking constitutes a health and disease risk factor. Through the process of infiltration in the soil, groundwater may be contaminated by the waste generated by human activity and deposited in the soil, waterways or air. The consumption of water in natura, captured in a spring, may lead to the risk of disease. One of the alternative technologies for disinfecting water that has shown promise is the generation of an oxidant solution in loco. The electrochemical reaction of sodium chloride produces oxidizing gases, which reacts with the water to produce the hypochlorite ion in balance with hypochlorous acid, along with traces of other oxidants. In the present study the development of a device based on an imported model that uses this type of technology wassought in order to reduce the cost of acquisition and makeit more available to disadvantaged communities with water quality issues. The evaluation of the efficiency of this technology in disinfecting water with different qualities (color and turbidity) was also sought, using total coliforms and Escherichia coli as indicator organisms of contamination. In each experimentthe quality of untreated water, and water after adding the oxidant was examined on turbidity, true color, residual chlorine, pH, temperature, and quantification of microorganism indicators. In the experiments performed we found that the adapted equipment showed to be as efficient in the production of disinfectant agents as the original equipment. In the microbiological assays performed on water contaminated with E. coli (synthesized water in a laboratory and natural) and total coliforms (natural water), the inactivation of these organisms was observed to be effective with the use of gases that came from the adapted equipment, taking into account the content of chlorine in water treated with the equipment. | Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Show more [+] Less [-]Custos de disponibilização e disposição a pagar pela água de rega: metodologia de análise | Costs of delivery and willingness to pay for irrigation water: methodology Full text
2011
Avillez, Francisco | Silva, Francisco Gomes da
Sustainable use of water resources should include the recognition that water has a social value, an environmental value and an economic value. The economic value of irrigation water should be expressed based on its price, which in turn is determined by the interplay of three factors: the cost of irrigation water (supply side), the willingness to pay for irrigation water (demand side) and public policies. This paper presents an analysis of the key methodological issues involved ineach of the above mentioned factors and how they influence the economic value of water
Show more [+] Less [-]Produção de aquênio do girassol irrigado com água salobra Full text
2011
Travassos, Kaline D.(Universidade Federal de Campina Grande Unidade Acadêmica de Engenharia Agrícola) | Soares, Frederico A. L.(IFGO) | Gheyi, Hans R.(Universidade Federal do Recôncavo da Bahia Núcleo de Engenharia de Água e Solo) | Silva, Débora R. S.(UFCG) | Nascimento, Ana K. S. do(Escola Superior de Agricultura Luiz de Queiroz Instituto Nacional de Ciência e Tecnologia em Engenharia da Irrigação) | Dias, Nildo da S.(UFERSA Departamento de Ciências Ambientais)
The aim of this study was to determine yield components and achene production of sunflower (Helianthus annuus L.) variety Embrapa 122/V-2000 irrigated with water of different salinities in a greenhouse. The treatments consisted of six levels of salinity of irrigation water (ECw), N1 - 0.5, N2 - 1.0; N3 - 2.0; N4 - 3.0; N5 - 4.0 and N6 - 5.0 dS m-1 at 25 oC in a randomized design with five replications. The internal diameter of the chapter, number of seeds, weight of 100 seeds, the total mass of seeds, dry weight of shoot and root, ratio of dry weight of root and shoot, water consumption, electrical conductivity of drainage water and the saturation extract of soil. The total mass of seeds and number of seeds decreased 11.39 and 9.64%, respectively, with per unit increase in electrical conductivity of irrigation water, the root dry mass was more affected by salinity of irrigation water than dry mass of aerial parts, salinity levels of drainage water at the end of experiment were about 2.2 times of electrical conductivity of saturation extract. | Objetivou-se com este trabalho verificar os componentes de produção e a produção de aquênios do girassol (Helianthus annuus L., variedade Embrapa 122/V-2000), sob irrigação com diferentes níveis de salinidade de água em ambiente protegido. Os tratamentos foram compostos de seis níveis de salinidade da água de irrigação (CEa): N1 - 0,5; N2 - 1,0; N3 - 2,0; N4 - 3,0; N5 - 4,0 e N6 - 5,0 dS m-1 a 25 oC, em delineamento inteiramente casualizado com 5 repetições. Avaliaram-se: o diâmetro interno do capítulo, número de aquênios, massa de 100 aquênios, massa total de aquênios, fitomassa seca da parte aérea e da raiz, relação fitomassa seca da raiz e da parte aérea, consumo de água, condutividade elétrica da água drenada e do extrato de saturação do solo. A massa total de aquênios e o número de aquênios decresceram de 11,39 e 9,64%, respectivamente, por aumento unitário da condutividade elétrica da água de irrigação; a fitomassa seca da raiz foi mais afetada pela salinidade da água de irrigação que a fitomassa seca da parte aérea, os níveis de salinidade da água de drenagem no final do experimento foi cerca de 2,2 vezes da condutividade elétrica do extrato de saturação.
Show more [+] Less [-]Novas formas de governança na política nacional da água Full text
2011
Rodrigues, Miguel
Comunicação apresentada no 8º Congresso Nacional de Administração Pública – Desafios e Soluções, em Carcavelos de 21 a 22 de Novembro de 2011.
Show more [+] Less [-]Efectividad del Nicosulfuron al cambiar el pH del agua Full text
2011
Sánchez M., Marcos T. | Pitty, Abelino | Pineda, Renán
Sánchez Medina, M.T. 2011. Efectividad del Nicosulfuron al cambiar el pH del agua. Proyecto especial de graduación del programa de Ingeniería Agronómica, Escuela Agrícola Panamericana, Zamorano. Honduras. 12 p. El uso de herbicidas es una de las prácticas principales para el manejo de malezas y está aumentando en los países en desarrollo. La calidad del agua es uno de los factores más importantes para la efectividad de los herbicidas. Uno de los aspectos importantes de la calidad del agua es el pH. El objetivo de este estudio fue evaluar la efectividad del herbicida Nicosulfuron (Accent® 75 WG) al modificar el pH del agua, usando dos dosis comerciales del mismo. Los pH utilizados fueron ácido, 3.3, y alcalino, 8.5. Las dosis utilizadas para cada pH fueron 50 y 70 g/ha. Como reguladores de pH se utilizó hidróxido de sodio y pH+®, como surfactante se utilizó ADSEE® 775. Se utilizó diseño de Bloques Completos al Azar (BCA) con cinco repeticiones. La efectividad del herbicida Nicosulfuron no aumentó al modificar el pH del agua, La dosis que tuvo más control sobre las malezas fue la de 70 g/ha. El efecto observado que el herbicida causó sobre las malezas fue una descoloración moderada, una marcada distorsión y recuperación esperada. También se realizó otro experimento para comparar el efecto de residualidad de dos lotes del herbicida, un lote vencido y un lote nuevo. El lote nuevo tuvo mayor efecto de residualidad que el lite vencido siendo 23% a los 7 días después de la aplicación y 16% a los 14 días después de la aplicación. | 1. Índice de cuadros,figuras y anexos 2. Introducción 3. Materiales y métodos 4. Resultados y discusión 5. Conclusiones 6. Recomendaciones 7. Literatura citada 8. Anexos
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