Formation and forecast of the daily price of the electric power in the chain Nare-Guatape-San Carlos

International Nuclear Information System (INIS)

Romero, Alejandro; Carvajal, Luis

2003-01-01

This work shows three different methodologies for the understanding and forecast of the electric energy prices in the chain Nare - Guatape - San Carlos: lineal multivariate model, autoregressive deterministic model and Fourier series decomposition. The electric energy price depends basically of the reservoir level and river flow, not only its own but the reservoir down and up, waters. About prices forecast, they can be modeled with an autoregressive process. Prices forecast follows the tendency and captures with acceptable precision the maximum prices due especially to the low hydrology and price variability for daily and weekly regulation reservoirs

Desarrollo poblacional de Diaspidiotus perniciosus (Hemiptera: Diaspididae en cultivos de manzano de San Carlos, Mendoza, Argentina

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Guillermo P. LOPEZ GARCIA

2011-01-01

Full Text Available Se estudió la bionomía de Diaspidiotus perniciosus Comstock (“escama de San José”, en manzanos de la variedad “Red delicious” de San Carlos, Mendoza, Argentina, durante los ciclos productivos 2007-2008 y 2008-2009. Se determinó el número de generaciones anuales y se estudiaron las fluctuaciones poblacionales asociadas a la integral térmica para la especie en esta región. D. perniciosus presenta dos generaciones superpuestas al ciclo del cultivo, mientras que las ninfas (N1 y N2 de la tercera generación se desarrollan solamente hasta el final de la temporada estival y pasan al estado de quiescencia, en el que permanecen durante el invierno. El desarrollo de D. perniciosus en esta zona coincide con el de esta especie en la zona frutícola del centro de Chile en cuanto al número de generaciones y al periodo de quiescencia invernal. La población quiescente en Chile está integrada predominantemente por ninfas del primer estadio (N1, mientras que en San Carlos, Mendoza, la población quiescente está integrada principalmente por ninfas del segundo estadio (N2. La similitudes entre ambas poblaciones se deben, probablemente, a las coincidencias en latitud, clima y especie hospedera. El impacto económico de D. perniciosus en la zona de estudio tiene mayor relevancia durante los meses de diciembre y enero, cuando se observa una alta incidencia de daños en los frutos y las hojas; este es el momento decisivo para implementar medidas de control fitosanitario. Estas deberán aplicarse en función de los máximos poblacionales de N1 que se producen con 600-650 Grados-Día (oD en diciembre y con 1.170-1.270oD en enero. En las temporadas en las que la densidad poblacional de la plaga es especialmente alta, podrían incorporarse medidas adicionales de control con 1.800-2.000oD durante el mes de abril. Los resultados de estos estudios representan una herramienta predictiva, que permitirá elaborar estrategias para el control de poblaciones de

Formas de participación en procesos democráticos recientes. Sociedad civil en San Carlos de Bariloche

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Paula Núñez

2012-02-01

Full Text Available Este trabajo explora los factores que inciden en los procesos sociales participativos, a partir de experiencias de los sectores vulnerables en San Carlos de Bariloche, Argentina. Los detalles de las formas participativas locales se enmarcan en el proceso de democratización nacional. El mismo ha enfrentado sucesivas crisis económicas y políticas, siendoparticularmente relevante el quiebre del año 2001. La recuperación de la gobernabilidad fue de la mano de discursos oficiales que reivindican la participación social en el diseño de políticas públicas. Exploraremos si las vías institucionales que se inauguran resuelven el ocultamiento proyectado sobre los sectores populares. Pondremos a la luz que, al privilegiar la idea de ciudadanía sobre la de sociedad civil, los prejuicios permanecen y se cristaliza el silencio de las voces populares.This paper explores the factors that affect social participatory processes, based on experiences of vulnerable groups in San Carlos de Bariloche. Details of local forms of participation are part of the Argentinian democratization process. The same has faced successive economic and political crises, being particularly significant the breakthrough of the year 2001. The recovery of capacity of governance is connected with the official argue claiming social participation in the design of public policies. We will explore if institutional initiatives solve the concealment projected over popular sectors. We will point out the fact that, when prioritising citizenship over civil society, prejudices remain and the silence of social voices crystallises.

Los trabajadores de empacadoras de yuca en comunidades de La Fortuna, San Carlos, y Sector Ángeles, San Ramón, Costa Rica. Una aproximación sociológica

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Francisco Rodríguez Barrientos

2012-08-01

Full Text Available El presente artículo se deriva del proyecto de investigación  Mejora en la eficiencia de la cadena productiva de la yuca en el distrito de La Fortuna, San Carlos, Costa Rica. El objetivo fundamental del proyecto consistía en mejorar la eficiencia y la productividad en las diversas etapas del proceso agro productivo de la yuca. La investigación se realizó en una franja territorial que abarcó un sector del distrito de La Fortuna, cantón de San Carlos, provincia de Alajuela, Costa Rica, un importante lugar de producción yuquera, y una porción del distrito de Peñas Blancas (cantón San Ramón, provincia de Alajuela. La franja territorial seleccionada se halla dentro de la Región Huetar Norte costarricense, cuyo sector ligado a la producción, procesamiento y comercialización de yuca constituyó la población meta de la investigación. El proyecto tuvo una duración de tres años (2006-2008. El presente artículo presenta un bosquejo comparativo entre trabajadores costarricenses y migrantes nicaragüenses que laboran en procesadoras de yuca de la franja territorial estudiada respecto a sus condiciones económicas, sociales y laborales. El artículo enfatiza algunas variables fundamentales como los niveles de ingreso y pobreza, los niveles de escolaridad y la tenencia de seguro social. La información ofrecida es una simple aproximación a una realidad compleja y cambiante, cuyos resultados se busca puedan servir de guía o de hipótesis de trabajo para ulteriores estudios que aborden esta problemática de forma más amplia y sistemática.

RELIGIOSIDAD POPULAR: EL CASO DE LA VIRGEN DE URKUPIÑA EN SAN CARLOS DE BARILOCHE.

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Ana Inés Barelli

2011-06-01

Full Text Available En los últimos años, la migración limítrofe en la Argentina no sólo se profundiza sino que inicia un proceso de visibilización social, dónde los aportes culturales y religiosos son percibidos y compartidos por toda la sociedad. La afluencia de estos grupos migratorios, en la Patagonia, dio lugar a un aporte cultural y religioso particular. El presente trabajo tiene como objetivo, poner en discusión el concepto de “religiosidad popular”, a la luz del caso de la devoción a la Virgen de Urkupiña de la comunidad boliviana en San Carlos de Bariloche. Analizaremos cómo las actividades religiosas y festivas de los migrantes bolivianos irrumpen en el espacio público generando nuevas adaptaciones devocionales, creando estrategias identitarias, y formulando nuevas territorialidades.

Efectos de la actividad humana en la cuenca del río San Carlos

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Adolfo Chaves Campos

Full Text Available Se analizó el efecto de las actividades agropecuarias en los recursos hídricos de la cuenca del río San Carlos, ubicado en la región noreste de Costa Rica, cuyo uso es fundamentalmente agropecuario. Los indicadores utilizados fueron: ph, temperatura, fosfatos, nitratos, oxígeno disuelto, sólidos totales, coliformes fecales y totales. Se determinó cuáles son los plaguicidas más utilizados y su impacto en el recurso hídrico; se verificó el arrastre de fertilizantes y partículas sólidas del suelo producto de la escorrentía superficial como consecuencia de las altas precipitaciones en zonas de explotación ganadera y cultivos, principalmente de caña de azúcar, piña, cítricos. Se encontró que existe una alta relación entre el nivel de las precipitaciones y la presencia de contaminantes en el cauce principal y cauces secundarios de la cuenca.

San Carlos: Un modelo de conexión social en medio de la violencia

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Héctor Fabio Guerrero Berrío

2015-12-01

Full Text Available El presente ensayo analiza la dinámica que ha tenido el conflicto armado en el municipio de San Carlos, Antioquía, durante la última década del siglo XX hasta la actualidad. Específicamente, analiza los daños morales, psicológicos y políticos que han generado las masacres de las veredas El Chocó y Dos Quebradas, así como las acciones de resistencia social que ha realizado la comunidad para la construcción de una nueva realidad a pesar de la violencia. Lo anterior sugiere la importancia de comprender el ejercicio de reflexión ética y de la memoria que han realizado las víctimas para configurar lo que, de acuerdo a la óptica de Iris Young, se denominaría un modelo de conexión social, y que les ha permitido asumir responsabilidades colectivas  para hacer frente a las injusticias estructurales que han padecido.

Una colección de esquelas impresas del siglo XVIII: la correspondencia del I Duque de San Carlos

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Lizarraga, Juan Manuel

2010-01-01

Full Text Available La Biblioteca Histórica de la UCM conserva una colección epistolar que reúne en un volumen facticio casi quinientas esquelas impresas con notificaciones, invitaciones y solicitudes remitidas al I Duque de San Carlos (1722-1797. El objeto de este artículo es presentar esta colección de impresos efímeros, su destinatario y remitentes, describir sus características físicas y formales así como apuntar una tipología y clasificación temática y abordar la problemática que presenta su datación cronológica. Esta colección de esquelas ofrece una valiosa información acerca del empleo de este particular género epistolar en la España del último cuarto del siglo XVIII así como de algunas costumbres y convenciones sociales de la nobleza madrileña de la época en lo que a rituales de invitación y notificación se refiereThe Historical Library of the UCM contains a collection of correspondence that gathers in a factitious volume nearly five hundred printed notifications, invitations and requests sent to the Duke of San Carlos (1722-1797. The purpose of this paper is to present this collection of printed ephemera, its recipient and senders, describing their physical and formal characteristics as well as pointing out a typology and thematic classification and address the issues presented by their chronological dating. This collection of printed correspondence provides valuable information on the use of this particular epistolary genre in Spain in the last quarter of the eighteenth century as well as on some of the social customs and conventions of the Madrid nobility as far as the rituals of invitation and notification are concerned.

[Modelling science. The ceroplastics of Ignacio Lacaba in the Colegio de Cirugía de San Carlos, Madrid].

Science.gov (United States)

Morente, Maribel

2016-01-01

Models made of wax had enormous diffusion in the anatomical teaching of the 18th century. It transcended the borders of a science that impregnated with scientific knowledge the artistic expression of beauty. Based on this premise, the San Carlos Royal College of Surgery created in Madrid a large collection of anatomical models, which is currently maintained by the Javier Puerta Anatomy Museum in the School of Medicine at Madrid Complutense University. The collection began in 1786 with Ignacio Lacaba, the first dissector of the Surgery College of Madrid, whose artistic sensibility and deep knowledge of anatomy contributed and facilitated harmonization between the work of the wax sculptors and language and anatomical expression.

76 FR 12720 - City of Escondido, CA, and Vista Irrigation District; Notice of Application Accepted for Filing...

Science.gov (United States)

2011-03-08

..., CA, and Vista Irrigation District; Notice of Application Accepted for Filing, Ready for Environmental...: City of Escondido, California (Escondido) and Vista Irrigation District (Vista). e. Name of Project... owned by the La Jolla, San Pasqual, and Rincon Indian Tribes. g. Filed Pursuant to: Federal Power Act...

25 CFR 137.1 - Water supply.

Science.gov (United States)

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Water supply. 137.1 Section 137.1 Indians BUREAU OF... CARLOS INDIAN IRRIGATION PROJECT, ARIZONA § 137.1 Water supply. The engineering report dealt with in... capacity of the San Carlos reservoir created by the Coolidge Dam and the water supply therefor over a...

The Creation of a Carmeleño Identity:Marriage Practices in the Indian Village at Mission San Carlos Borromeo del Río Carmel

OpenAIRE

Peelo, Sarah

2010-01-01

Indigenous peoples from diverse tribelets lived within the Indian village at Mission San Carlos Borromeo del Río Carmel. In precolonial times, California Indians formed identities tied to their tribelets. In the mission, those identities were reproduced as members of this pluralistic community formed a connection with their new place of residence. In this paper, I illustrate how marriage was one arena within which different indigenous peoples at this mission may have created a shared sense o...

Irrigation management to optimize controlled drainage in a semi-arid area

OpenAIRE

Soppe, R.W.O.; Ayars, J.E.; Christen, E.W.; Shouse, P.J.

2003-01-01

On the west side of the San Joaquin Valley, California, groundwater tables have risen after several decades of irrigation. A regional semi-permeable layer at 100 m depth (Corcoran Clay) combined with over-irrigation and leaching is the major cause of the groundwater rise. Subsurface drain systems were installed from the 60¿s to the 80¿s to remove excess water and maintain an aerated root zone. However, drainage water resulting from these subsurface systems contained trace elements like seleni...

Deficit irrigation of peach trees to reduce water consumption

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Lack of water is a major limiting factor for production tree fruits such as peaches in the San Joaquin Valley of California and many other arid- or semi-arid regions in the world. Deficit irrigation can be used in some cropping systems as a water resource management strategy to reduce non-productiv...

SAN MICHELE. ENTRE CIELO Y MAR / San Michele, between sky and sea

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Pablo Blázquez Jesús

2012-11-01

Full Text Available RESUMEN El cementerio es uno de los tipos arquitectónicos más profundos y metafóricos. El concurso para la ampliación del cementerio de San Michele, convocado en 1998 por la administración Municipal de Venecia, se convierte en un excelente campo de pruebas sobre el que poder analizar el contexto histórico en torno a esta tipología, y su relación con la ciudad y el territorio. El estudio de este caso concreto nos permite descubrir personajes, relaciones casuales y hallazgos que se despliegan a lo largo del texto. La historia del cementerio de San Michele es también la crónica de la transformación de la ciudad de Venecia y su Laguna. Interpretando este concurso como un instrumento de investigación, el objetivo del artículo es el de comprender la realidad contemporánea de la arquitectura funeraria a través de la isla de San Michele, Venecia, y las propuestas finalistas de Carlos Ferrater, Enric Miralles y David Chipperfield. Una historia bajo la cual se vislumbran claves que nos sirven para reflexionar acerca del cementerio contemporáneo, la ciudad y el territorio. SUMMARY The cemetery is one of the most profound and metaphorical kinds of architecture. The competition for the extension of the San Michele Cemetery, called in 1998 by the Venice municipal administration, is an excellent testing ground on which to analyse the historical context surrounding this type of architecture, and its relationship with the city and the region. The study of this particular case allows us to uncover characters, casual relationships and findings that unfold throughout the text. The history of the San Michele cemetery is also the chronicle of the transformation of the city of Venice and its Lagoon. Interpreting this competition as a research tool, the aim of the paper is to understand the contemporary reality of funerary architecture through the island of San Michele, Venice, and the finalist proposals of Carlos Ferrater, Enric Miralles and David

A new record for American Bullfrog (Lithobates catesbeianus in San Juan, Argentina Nuevo registro de rana toro americana (Lithobates catesbeianus en San Juan, Argentina

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Eduardo Sanabria

2011-03-01

Full Text Available We report a new record of Lithobates catesbeianus (American bullfrog from Argentina. L. catesbeianus was first introduced to San Juan Province 11 years ago in Calingasta Department, where the habitat is pre-cordilleran. The new record is for Zonda Department, San Juan Province, in the Monte desert region. Here, L. catesbeianus uses artificial ponds for reproduction and tadpole development. These ponds receive water from an irrigation system that connects the whole agriculture land in the region. The tadpoles use the irrigation canals to move among ponds. We suggest that legislation should be established to prevent future invasions and to achieve sustainable management of the wild American bullfrog populations in San Juan. Prevention of future invasion and management of established populations of this species requires the cooperation of numerous stake holders.Se presenta un nuevo registro de Lithobates catesbeianus (rana toro americana en Argentina. L. catesbeianus fue introducida por primera vez a la provincia de San Juan hace 11 años en el Departamento Calingasta, donde el hábitat es pre-cordillerano. El nuevo registro es para el Departamento Zonda en la provincia de San Juan, en el desierto del Monte. En este sitio, L. catesbeianus usa estanques artificiales para la reproducción y desarrollo del renacuajo. Los estanques reciben agua de un sistema de riego que conecta todas las tierras de la agricultura en la región. Los renacuajos utilizan los canales de riego para moverse entre los estanques. Sugerimos que se establezcan leyes para prevenir invasiones futuras y para lograr un manejo integrado de las poblaciones silvestres de rana toro que se encuentran en San Juan. La prevención de futuras invasiones y el manejo de las poblaciones establecidas de esta especie requieren la cooperación de numerosas entidades tanto gubernamentales como privadas.

Tumores gástricos malignos en el Hospital San Juan de Dios y la Clínica Carlos Lleras Restrepo de Bogotá

OpenAIRE

Viviana L. Arias; Mauricio A. Paláu; Juan José Yunis; Diana Palacios; Orlando Ricaurte

2001-01-01

Se revisaron 9.349 informes de estudios de especímenes quirúrgicos del archivo del Departamento de Patología del Hospital San Juan de Dios y la Clínica Carlos Lleras Restrepo de Bogotá en el tiempo comprendido entre enero 1 de 1999 y mayo 31 de 2000. Se seleccionaron los especímenes con diagnóstico de tumores gástricos que correspondieron al 8,61% de los casos; 2,41% fueron tumores benignos y 6,2% malignos De éstos 91,67% fueron adenocarcinomas, 2,78 % linfomas, 1,85% tumores carcinoides y 1,...

‘Historiography and the retracing of Latin American art history’: The Academy of San Carlos and Mexican Art History by Ray Hernández-Durán, Politics, History, and Art in Nineteenth-Century Mexico, London and New York: Routledge, 2017

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Claudia Mattos Avolese

2017-12-01

Full Text Available The Academy of San Carlos and Mexican Art History presents an account of the cultural and political circumstances that led to the installation of the first gallery of colonial art at the Academy of San Carlos in mid-nineteenth century Mexico City, and to the associated publication of the first art historical account of colonial Mexico. The author proposes that these two endeavors relate closely to the ambitions of the Mexican conservative elite to create a Mexican corporate identity based on the colonial past. Ray Hernández-Durán also argues that the gallery and the associated book can be seen as the starting point for the construction of the field of Latin American art history as we know it today.

Heterogeneous hydrogen distribution in orthopyroxene from veined mantle peridotite (San Carlos, Arizona): Impact of melt-rock interactions

Science.gov (United States)

Denis, Carole M. M.; Demouchy, Sylvie; Alard, Olivier

2018-03-01

Experimental studies have shown that hydrogen embedded as a trace element in mantle mineral structures affects the physical properties of mantle minerals and rocks. Nevertheless, hydrogen concentrations in mantle minerals are much lower than predicted by hydrogen solubilities obtained experimentally at high pressure and temperature. Here, we report textural analyses and major and trace element concentrations (including hydrogen) in upper mantle minerals from a spinel-bearing composite xenolith (dunite and pyroxenite) transported by silica-undersaturated mafic alkaline lavas from the San Carlos volcanic field (Arizona, USA). Our results suggest that the composite xenolith results from the percolation-reaction of a basaltic liquid within dunite channels, and is equilibrated with respect to trace elements. Equilibrium temperatures range between 1011 and 1023 °C. Hydrogen concentrations (expressed in ppm H2O by weight) obtained from unpolarized and polarized Fourier transform infrared spectroscopy are low, with average values water stored in the Earth's upper mantle.

Etiquetado semáforo: estudio del hábito de compras en jugos procesados, en el barrio de San Carlos de la ciudad de Quito

OpenAIRE

Maya Izurieta, María Eugenia

2015-01-01

Este estudio presenta una investigación cualitativa y cuantitativa del hábito de compra de jugos y bebidas de frutas envasadas, en el canal tiendas y micro mercados en el barrio San Carlos, parroquia la Concepción de la ciudad de Quito, luego de un año de la vigencia del Reglamento Sanitario Sustitutivo de Etiquetado de Alimentos Procesados para el Consumo Humano desde el mes de agosto del 2014. El objetivo general conocer si los compradores de jugos y bebidas de frutas procesadas del barrio ...

Remote sensing analysis of vegetation at the San Carlos Apache Reservation, Arizona and surrounding area

Science.gov (United States)

Norman, Laura M.; Middleton, Barry R.; Wilson, Natalie R.

2018-01-01

Mapping of vegetation types is of great importance to the San Carlos Apache Tribe and their management of forestry and fire fuels. Various remote sensing techniques were applied to classify multitemporal Landsat 8 satellite data, vegetation index, and digital elevation model data. A multitiered unsupervised classification generated over 900 classes that were then recoded to one of the 16 generalized vegetation/land cover classes using the Southwest Regional Gap Analysis Project (SWReGAP) map as a guide. A supervised classification was also run using field data collected in the SWReGAP project and our field campaign. Field data were gathered and accuracy assessments were generated to compare outputs. Our hypothesis was that a resulting map would update and potentially improve upon the vegetation/land cover class distributions of the older SWReGAP map over the 24,000  km2 study area. The estimated overall accuracies ranged between 43% and 75%, depending on which method and field dataset were used. The findings demonstrate the complexity of vegetation mapping, the importance of recent, high-quality-field data, and the potential for misleading results when insufficient field data are collected.

Control de Dysmicoccus brevipes (Hemiptera: Pseudococcidae, en el fruto de piña, San Carlos, Costa Rica

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Alexandra Miranda Vindas

2013-01-01

Full Text Available Se evaluaron 6 productos para el control de Dysmicoccus brevipes en piña (Ananas comosus. El ensayo de laboratorio se realizó en el Laboratorio de Biocontroladores de la empresa BioEco Natural S.A., ubicada en Aguas Zarcas, San Carlos, mientras que los ensayos de campo se realizaron en una plantación comercial de piña, en Venecia de San Carlos. En el laboratorio se evaluó Beauveria bassiana (4,0 x 1010 esporas.g-1; Metarhizium anisopliae (1,0 x 1010 esporas.g-1; una mezcla de ambos hongos (0,5 g + 0,5 g.l-1 de agua destilada, de 4,0 x 1010 esporas.g-1 + 1,0 x 1010 esporas.g-1; un jabón líquido de sales potásicas, “Goyca”® (7 ml.l-1; el extracto botánico(Biorep® (mezcla de chile picante, ajo, cebolla, mostaza y gavilana (7 ml.l-1; y agua destilada como testigo. Los resultados más promisorios fueron con el extracto botánico y el jabón líqui do, los que causaron una mortalidad más rápida. Los tratamientos evaluados en la plantacióncomercial de piña, var. MD-2, fueron los mis mos, a excepción del testigo en donde se utilizó los productos utilizados de forma comercial en la finca: Diazinon® 60 EC (diazinon (0,5 ml.l-1 y Sevin® 80 WP (carbaril (1 kg.ha-1. El extrac to botánico resultó en la menor incidencia de cochinillas (X=6,4, < al testigo (X=10,8, < el Goyca® (X=13,7, < M. anisopliae (X=44,4, < B. bassiana (X=45,1, y

Caracterización histórica y socioeconómica de una franja territorial yuquera en el distrito de La Fortuna, San Carlos y Peñas Blancas, San Ramón, región Huetar Norte de Costa Rica

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Francisco Rodríguez-Barrientos

2014-05-01

Full Text Available El presente artículo se deriva del proyecto de investigación “Mejora en la eficiencia de la cadena productiva de la yuca en el distrito de La Fortuna, San Carlos, Costa Rica”. Su objetivo fundamental consistía en mejorar la eficiencia y la productividad en las diversas etapas del proceso agroproductivo de la yuca. La investigación se realizó en una franja territorial que abarcó un sector del distrito de La Fortuna, cantón de San Carlos, provincia de Alajuela, Costa Rica, tradicionalmente un importante lugar de producción yuquera, y otro del distrito de Peñas Blancas (cantón de San Ramón, provincia de Alajuela. Esa franja territorial es parte de la Región Huetar Norte costarricense y su sector ligado a la producción, procesamiento y comercialización de yuca constituyó la población meta de la investigación. El proyecto tuvo una duración de tres años (2006-2008. En este artículo se hace una caracterización histórica, social y económica de dicha franja territorial. Además, se analizan las consecuencias económicas y sociales, tanto para las comunidades ubicadas en la franja territorial estudiada como para la región de la que forman parte, derivadas de los cambios ocurridos en los ámbitos nacional e internacional, sobre todo en los últimos treinta años. De este modo, se intenta perfilar el alcance y la índole de las eventuales transformaciones acaecidas en la franja seleccionada, ubicando siempre el análisis en el contexto de la región Huetar Norte. Posteriormente se publicarán más artículos con los resultados obtenidos en las etapas agrícola, industrial (maquiladoras y empacadoras y social, destacando lo relacionado con la situación de los trabajadores en las empacadoras, haciendo énfasis en los migrantes nicaragüenses.

Economic risk assessment of drought impacts on irrigated agriculture

Science.gov (United States)

Lopez-Nicolas, A.; Pulido-Velazquez, M.; Macian-Sorribes, H.

2017-07-01

In this paper we present an innovative framework for an economic risk analysis of drought impacts on irrigated agriculture. It consists on the integration of three components: stochastic time series modelling for prediction of inflows and future reservoir storages at the beginning of the irrigation season; statistical regression for the evaluation of water deliveries based on projected inflows and storages; and econometric modelling for economic assessment of the production value of agriculture based on irrigation water deliveries and crop prices. Therefore, the effect of the price volatility can be isolated from the losses due to water scarcity in the assessment of the drought impacts. Monte Carlo simulations are applied to generate probability functions of inflows, which are translated into probabilities of storages, deliveries, and finally, production value of agriculture. The framework also allows the assessment of the value of mitigation measures as reduction of economic losses during droughts. The approach was applied to the Jucar river basin, a complex system affected by multiannual severe droughts, with irrigated agriculture as the main consumptive demand. Probability distributions of deliveries and production value were obtained for each irrigation season. In the majority of the irrigation districts, drought causes a significant economic impact. The increase of crop prices can partially offset the losses from the reduction of production due to water scarcity in some districts. Emergency wells contribute to mitigating the droughts' impacts on the Jucar river system.

25 CFR 137.2 - Availability of water.

Science.gov (United States)

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Availability of water. 137.2 Section 137.2 Indians BUREAU... COSTS, SAN CARLOS INDIAN IRRIGATION PROJECT, ARIZONA § 137.2 Availability of water. Pursuant to section... notice to announce when water is actually available for lands in private ownership under the project and...

Un estudio geográfico regional de la inmigración nicaragüense y sus efectos sobre los servicios de obstetricia del Hospital de San Carlos. Provincia de Alajuela. Costa Rica.

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Amalia Carvajal Alvarado

2011-08-01

Full Text Available El presente trabajo de investigación se centrará en realizar un diagnóstico de la población inmigrante de nacionalidad nicaragüense que hace uso de los servicios de salud que brindad el Hospital San Carlos. Se analizará la población nicaragüense que ingresó al servicio de obstetricia del Hospital San Carlos del 01 de octubre de 1995 al 31 noviembre de 1996, en virtud de que el hacerlo a toda la población resultaría altamente complejo y considerándose que este grupo de población tomada para el presente estudio refleja la realidad que viven la mayoría de inmigrantes nicaragüenses al ingresar al país, al diagnosticar un problema que altera silenciosamente el funcionamiento administrativo de la institución y su contexto. Cuando éste supera los límites de la oferta, se provoca una sobre- utilización de los Servicios ( personal médico y de apoyo que origina que el sistema organizativo de la institución colapse en virtud de no contarse con un nivel de planificación adecuado que permita prever situaciones emergentes.

Modeling pesticide loadings from the San Joaquin watershed into the Sacramento-San Joaquin Delta using SWAT

Science.gov (United States)

Chen, H.; Zhang, M.

2016-12-01

The Sacramento-San Joaquin Delta is an ecologically rich, hydrologically complex area that serves as the hub of California's water supply. However, pesticides have been routinely detected in the Delta waterways, with concentrations exceeding the benchmark for the protection of aquatic life. Pesticide loadings into the Delta are partially attributed to the San Joaquin watershed, a highly productive agricultural watershed located upstream. Therefore, this study aims to simulate pesticide loadings to the Delta by applying the Soil and Water Assessment Tool (SWAT) model to the San Joaquin watershed, under the support of the USDA-ARS Delta Area-Wide Pest Management Program. Pesticide use patterns in the San Joaquin watershed were characterized by combining the California Pesticide Use Reporting (PUR) database and GIS analysis. Sensitivity/uncertainty analyses and multi-site calibration were performed in the simulation of stream flow, sediment, and pesticide loads along the San Joaquin River. Model performance was evaluated using a combination of graphic and quantitative measures. Preliminary results indicated that stream flow was satisfactorily simulated along the San Joaquin River and the major eastern tributaries, whereas stream flow was less accurately simulated in the western tributaries, which are ephemeral small streams that peak during winter storm events and are mainly fed by irrigation return flow during the growing season. The most sensitive parameters to stream flow were CN2, SOL_AWC, HRU_SLP, SLSUBBSN, SLSOIL, GWQMN and GW_REVAP. Regionalization of parameters is important as the sensitivity of parameters vary significantly spatially. In terms of evaluation metric, NSE tended to overrate model performance when compared to PBIAS. Anticipated results will include (1) pesticide use pattern analysis, (2) calibration and validation of stream flow, sediment, and pesticide loads, and (3) characterization of spatial patterns and temporal trends of pesticide yield.

Non-symbiotic bacterial diazotrophs from of agricultural crops of San Carlos. Córdoba, Colombia

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Cecilia Lara Mantilla

2007-07-01

Full Text Available Diazotrophic Azotobacter sp and Azospirrillum sp bacteria were isolated from the rhizosphere of plantain, (Musa paradisiaca, corn, wheat and fallow areas (uncultivated, but covered by fallen leaves in the San Carlos region (in the Sinú valley in the Córdoba department, Colombia. Microbial populations were identified by biochemical tests; physiological characters were examined using Gram reaction in different mediums: Burk’s, Ashby and Jensen’s (Azotobacter sp and Burk’s, NFB and Congo-red medium (Azospirillum sp. The study was aimed at determining ion ammonium production from Azotobacter sp and Azospirrillum sp isolates; ion ammonium was quantified according to Berthelot’s colorimetric technique (phenol-hypochlorite. This method was modified and standardised in line with using a Perkin-Elmer Lamba 11 UV-Vis spectrometer. As a result of this study, 14 isolates have been shown to be ammonium-producers at concentrations ranging from 0.9 mg/l to 5.2 mg/l; A16PG (5.1545 mg/l and A26M1P (5.1743 mg/l yielded the highest ammonium concentrations for Azotobacter sp and A5M1G (4.6741 mg/l for Azospirrillum sp. Biological N2 fixation (BNF by associative diazotrophic bacteria has contributed towards increasing harvest yield, thereby reducing the need for nitrogenised fertilisers and the emission of greenhouse gases (such as N2O and obtaining economic and environmental benefits for farming.

Inferring soil salinity in a drip irrigation system from multi-configuration EMI measurements using adaptive Markov chain Monte Carlo

Science.gov (United States)

Zaib Jadoon, Khan; Umer Altaf, Muhammad; McCabe, Matthew Francis; Hoteit, Ibrahim; Muhammad, Nisar; Moghadas, Davood; Weihermüller, Lutz

2017-10-01

A substantial interpretation of electromagnetic induction (EMI) measurements requires quantifying optimal model parameters and uncertainty of a nonlinear inverse problem. For this purpose, an adaptive Bayesian Markov chain Monte Carlo (MCMC) algorithm is used to assess multi-orientation and multi-offset EMI measurements in an agriculture field with non-saline and saline soil. In MCMC the posterior distribution is computed using Bayes' rule. The electromagnetic forward model based on the full solution of Maxwell's equations was used to simulate the apparent electrical conductivity measured with the configurations of EMI instrument, the CMD Mini-Explorer. Uncertainty in the parameters for the three-layered earth model are investigated by using synthetic data. Our results show that in the scenario of non-saline soil, the parameters of layer thickness as compared to layers electrical conductivity are not very informative and are therefore difficult to resolve. Application of the proposed MCMC-based inversion to field measurements in a drip irrigation system demonstrates that the parameters of the model can be well estimated for the saline soil as compared to the non-saline soil, and provides useful insight about parameter uncertainty for the assessment of the model outputs.

Inferring soil salinity in a drip irrigation system from multi-configuration EMI measurements using adaptive Markov chain Monte Carlo

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K. Z. Jadoon

2017-10-01

Full Text Available A substantial interpretation of electromagnetic induction (EMI measurements requires quantifying optimal model parameters and uncertainty of a nonlinear inverse problem. For this purpose, an adaptive Bayesian Markov chain Monte Carlo (MCMC algorithm is used to assess multi-orientation and multi-offset EMI measurements in an agriculture field with non-saline and saline soil. In MCMC the posterior distribution is computed using Bayes' rule. The electromagnetic forward model based on the full solution of Maxwell's equations was used to simulate the apparent electrical conductivity measured with the configurations of EMI instrument, the CMD Mini-Explorer. Uncertainty in the parameters for the three-layered earth model are investigated by using synthetic data. Our results show that in the scenario of non-saline soil, the parameters of layer thickness as compared to layers electrical conductivity are not very informative and are therefore difficult to resolve. Application of the proposed MCMC-based inversion to field measurements in a drip irrigation system demonstrates that the parameters of the model can be well estimated for the saline soil as compared to the non-saline soil, and provides useful insight about parameter uncertainty for the assessment of the model outputs.

Inferring soil salinity in a drip irrigation system from multi-configuration EMI measurements using adaptive Markov chain Monte Carlo

KAUST Repository

Jadoon, Khan Zaib

2017-10-26

A substantial interpretation of electromagnetic induction (EMI) measurements requires quantifying optimal model parameters and uncertainty of a nonlinear inverse problem. For this purpose, an adaptive Bayesian Markov chain Monte Carlo (MCMC) algorithm is used to assess multi-orientation and multi-offset EMI measurements in an agriculture field with non-saline and saline soil. In MCMC the posterior distribution is computed using Bayes\\' rule. The electromagnetic forward model based on the full solution of Maxwell\\'s equations was used to simulate the apparent electrical conductivity measured with the configurations of EMI instrument, the CMD Mini-Explorer. Uncertainty in the parameters for the three-layered earth model are investigated by using synthetic data. Our results show that in the scenario of non-saline soil, the parameters of layer thickness as compared to layers electrical conductivity are not very informative and are therefore difficult to resolve. Application of the proposed MCMC-based inversion to field measurements in a drip irrigation system demonstrates that the parameters of the model can be well estimated for the saline soil as compared to the non-saline soil, and provides useful insight about parameter uncertainty for the assessment of the model outputs.

Joint irrigation districts hydropower assessment study. Final feasibility assessment report. Volume I

Energy Technology Data Exchange (ETDEWEB)

None

1979-02-01

In August 1978, the United States Department of Energy and the Turlock Irrigation District entered into a cooperative agreement for a Joint District's Low-Head Hydropower Assessment Study. The purpose of the agreement was to carry out a study of the hydropower potential at sites within the borders of the Turlock, Merced, South San Joaquin, and Oakdale Irrigation Districts in California. The required data were gathered and analyzed. The results of this study indicate the total potential small hydropower capacity with the Joint Districts is 19,560 kW installed with an annual energy generation of 68,561,800 kWh. This is equivalent to oil-savings of 118,616 barrels per y.

División social del espacio residencial y migraciones: El caso de San Carlos de Bariloche, Argentina

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Brenda Matossian

2015-09-01

Full Text Available El espacio intraurbano en las ciudades contemporáneas de América Latina acusa profundas divisiones sociales, dado el tipo de desarrollo que han tenido bajo los modelos neoliberales imperantes. En este artículo se analiza la ciudad como parte de un devenir histórico-político particular, desde un enfoque multidimensional en el que se hace especial énfasis en la relación establecida entre las divisiones territoriales internas y el componente migratorio de la población. San Carlos de Bariloche (Patagonia argentina posee una heterogénea composición étnico-cultural, fruto de diversos flujos migratorios internos e internacionales. Profundas y complejas distancias materiales y simbólicas separan la ciudad turística (la "Suiza argentina" asociada a una elite nutrida por migrantes internos urbanos y europeos, de la ciudad de "El Alto", donde migrantes internos rurales y chilenos se han asentado en barrios populares. La relación clase-origen se entrelaza en una división social del espacio residencial, que se profundiza y produce segregación urbana y refuerza las tensiones.

Evaluación y modificación del Sistema de Tratamiento de Aguas Residuales de la Planta de Matanza del ITCR en Santa Clara, San Carlos

OpenAIRE

Deloya Martínez, Alma

2006-01-01

La planta de matanza de ganado vacuno y porcino del ITCR, Sede San Carlos, en Santa Clara, procesa en promedio 23 reses y 11 cerdos por día. El caudal de aguas residuales promedio generado durante el proceso de matanza varió de un máximo de 72 m3/día hasta un mínimo de 12 m3/día. Las aguas residuales son tratadas en un sistema de tratamiento biológico anaerobio, para controlar la contaminación del agua, según el Reglamento de vertido y reúso de aguas residuales. El sistema original consistió ...

Eritrocitosis secundaria a hipoxemia como factor pronóstico en pacientes con neumopatía crónica exacerbada. Fundación Hospital San Carlos. Bogotá D.C., Colombia.

OpenAIRE

Galindo Pedraza, Javier Leonardo

2012-01-01

Objetivo. Establecer si existe relación entre los distintos niveles de hematocrito con el pronóstico a 30 días en pacientes admitidos a la Fundación Hospital San Carlos con impresión diagnóstica de neumopatía crónica exacerbada e hipoxemia secundaria. Contexto y tipo de estudio. Estudio observacional de una única cohorte prospectiva pronóstica, teniendo como unidad de análisis los pacientes admitidos entre marzo de 2011 a octubre de 2011. Materiales y métodos. Se llevó a cab...

Significados en torno a la indemnización y la restitución en víctimas del conflicto armado en el municipio de San Carlos

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Villa Gómez, Juan David

2016-02-01

Full Text Available Resumen. Se resultados de las indagaciones sobre la valoración que las mismas víctimas del conflicto armado, del municipio de San Carlos Antioquia (Colombia, hacen de la implementación de la Ley 1448 (Ley de Victimas; dicho proceso de investigación, evidenció entre otros hallazgos, la contradicción entre el discurso oficial y el relato de las víctimas en relación a los procesos de reparación, discursos contradictorios respecto a la transición, el estado de vulneración e insatisfacción de necesidades básicas de las personas victimizadas así como una alta confusión en la implementación de la Ley. Estos resultados, entre otros, permiten afirmar que, la reparación hoy, dista mucho de ser un proceso que aporte a la reconstrucción del tejido social, a la paz y la reconciliación. Abstract. The results of the inquiries on the valuation that the very victims make of the armed conflict, in the Municipality of San Carlos, Antioquia, Colombia of the implementation of the 1448 Law (Law of victims; such a process of research, made evident among other findings, the contradiction between the official discourse and the story of the victims in relation to the processes of repair, contradictory speeches regarding the transition, the state of infringement and dissatisfaction of victimized people’s basic needs, as well as a high confusion in the implementation of the Law. These findings, among others, allow to affirm that, repair today, is very far from being a process that contributes to the reconstruction of the social fabric, to peace, and reconciliation.

Seroprevalence of Toxoplasma gondii in Cats (Felis catus, Linnaeus 1758 Living in San Carlos (Chile

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Ignacio Eduardo Troncoso Toro

2015-05-01

Full Text Available There are few studies about seroprevalence of toxoplasmosis in Chile; therefore, this article aims to determine seroprevalence in cats in the district of San Carlos, by ELISA Immuno- Comb® serological technique, and, at the same time, to examine association with variables of sex, age, diet, and habitat. To the effect, 60 cats over 2 months old were randomly sampled. Sera were analyzed using the ELISA ImmunoComb® Biogal Toxo & Chlamydia test kit, which detects specific immunoglobulin G-type antibodies against Toxoplasma gondii with a sensitivity of 92.3% and a specificity of 100%. The study evidenced that 29 individuals were positive (48.3% seroprevalence; when broken down by gender this corresponded to 9 males and 20 females (39.1% and 54%, respectively. By age, seropositivity was higher in the “Adult” group (76.7%, followed by groups “Over 7 years” (50% and “Young” (25%. With respect to diet, higher seropositivity was obtained in animals fed on mixed diet, as opposed to commercial diet (60% vs. 47.2%. By variable habitat, 16 indoor and 13 outdoor cats were positive (45.7% and 52%, showing statistically significant difference only for the variable age (p < 0.05. Finally, through relating age with seropositivity, a negative correlation was evidenced (r = –0.3, indicating that older individuals had lower seroprevalence. The results show the presence of antibodies against Toxoplasma gondii in domestic cats.

Use of Ionizing Radiation by the students of the Faculty of Odontology of the Universidad de San Carlos de Guatemala. Radiographic Techniques evaluation

International Nuclear Information System (INIS)

Ramirez Montenegro, E.S. del

2000-01-01

In the present thesis an evaluation of the radiographic techniques was made by the students in the clinics of the Faculty of Odontology in the Universidad de San Carlos. The sample was 56 students of fourth and fifth year, an survey form was designed including information about radiographic technique, pacient, film seting up, cone alineation, furthermore exposure repetitions and its cause. It was conclude that paralelism technique is used by 46% of the students, 41% bicectriz technique, 13% both techniques, 100 % aleta mordible. Regarding to equipment set up previous to exposure 88% of the students sets the equipment in acceptable way, 88% used XCP accesory to hold the film without desinfection procedures and it was not set up properly. A 92% of the evaluated student had to repeat the exposures due to wrong application of radiographic techniques

Occurrence and parasitism of aphids (Hemiptera: Aphididae on cultivars of irrigated oat (Avena spp. in São Carlos, Brazil

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Júlio Cesar Ronquim

2004-06-01

Full Text Available The interactions between aphids and their Hymenopteran parasitoids on irrigated oats as well as the response of different cultivars of cereals regarding the resistance to these aphids and the influence on the host/parasitoid relationships were studied during two years in São Carlos, Brazil. Rhopalosiphum padi (L. was the predominant aphid observed throughout the study, while the other species were rarely found. Five species of parasitic Hymenoptera were found: three primary parasitoids, Lysiphlebus testaceipes (Cresson, Aphidius colemani (Viereck and Diaeretiella rapae (M'Intosh and two hyperparasitoids, Syrphophagus aphidivorus (Myer and Alloxysta brassicae (Ashmead. The UPF 86081 cultivar presented significant results regarding lower Rhopalosiphum padi contamination and higher aphid parasitism rates than those observed on some other cultivars. No significant effect on the percentage variation of parasitoid emergence on the mummified aphids was observed throughout this study.Foram avaliadas as interações entre afídeos e seus himenópteros parasitóides em cultivares de aveia irrigada, como também a resposta de diferentes cultivares em relação resistência à estes afídeos e a influência nas relações hospedeiro/parasitóide durante dois anos em São Carlos, SP, Brasil. Rhopalosiphum padi (L. foi o afídeo predominante ao longo do estudo, enquanto as outras espécies raramente foram encontradas. Foram observadas cinco espécies de himenópteros parasitóides: três parasitóides primários, Lysiphlebus testaceipes (Cresson, Aphidius colemani (Viereck e Diaeretiella rapae (M'Intosh e dois hiperparasitóides, Syrphophagus aphidivorus (Myer and Alloxysta brassicae (Ashmead. A cultivar UPF 86081 apresentou resultados significativos quanto à baixa infestação por Rhopalosiphum padi e maiores taxas de parasitismo que a demais cultivares. Não foi observado efeito significativo na variação de porcentagem de emergência de parasit

Occurrence and distribution of dissolved pesticides in the San Joaquin River basin, California

Science.gov (United States)

Panshin, Sandra Yvonne; Dubrovsky, Neil M.; Gronberg, JoAnn M.; Domagalski, Joseph L.

1998-01-01

generally low percentage of irrigation return flow and contribution of pesticide-free streamflow from reservoir releases. Irrigation return flows in the Orestimba Creek and Salt Slough subbasins generally contained more pesticides at higher concentrations. In addition, the distribution of seven pesticides (alachlor, cyanazine, dacthal, fonofos, molinate, napropamide, and trifluralin) in the subbasins showed a direct spatial correspondence between occurrence and application rates. Temporal patterns of occurrence also were affected by patterns of application and hydrology. Most pesticides showed a clear correspondence between the times of their application and their occurrence. Fourteen pesticides had maximum application and concentrations during the summer irrigation season. However, several pesticides exhibited maximum concentrations during winter storms, although maximum application occurred at some other time of year?the result of differences in precipitation and streamflow between seasons. In some subbasins, precipitation runoff was more effective than irrigation return flows at transporting pesticides from the site of application to the stream. Also, during autumn, when there was neither precipitation nor irrigation, the transport of pesticides to streams was limited. The effect of chemical and physical properties on the occurrence of pesticides was examined for the San Joaquin River Basin as a whole. The runoff potential of each pesticide, calculated from the solubility, water-soil organic carbon partition coefficient Koc, and hydrolysis half-life, is generally consistent with the frequency of detection of pesticides in surface water in relation to the amount applied. These three properties each were generally, and weakly, correlated with the relative load of the pesticides in surface water. Pesticide occurrence and concentrations at the mouth of the basin (the San Joaquin River near Vernalis) was compared with pesticide occurrence and concentration in the three

Optimized Subsurface Irrigation System: The Future of Sugarcane Irrigation

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M. H. J. P. Gunarathna

2018-03-01

Full Text Available Climate change may harm the growth and yield of sugarcane (Saccharum officinarum L. without the introduction of appropriate irrigation facilities. Therefore, new irrigation methods should be developed to maximize water use efficiency and reduce operational costs. OPSIS (optimized subsurface irrigation system is a new solar-powered automatic subsurface irrigation system that creates a phreatic zone below crop roots and relies on capillarity to supply water to the root zone. It is designed for upland crops such as sugarcane. We investigated the performance of OPSIS for irrigating sugarcane and evaluated its performance against sprinkler irrigation under subtropical conditions. We conducted field experiments in Okinawa, Japan, over the period from 2013 to 2016 and took measurements during spring- and summer-planted main crops and two ratoon crops of the spring-planted crop. Compared with sprinkler irrigation, OPSIS produced a significantly higher fresh cane yield, consumed less irrigation water and provided a higher irrigation water use efficiency. We conclude that OPSIS could be adopted as a sustainable solution to sugarcane irrigation in Okinawa and similar environments.

[Responsible ownership of dogs and human health in neighborhoods of San Carlos de Bariloche, Argentina].

Science.gov (United States)

Garibotti, Gilda; Zacharías, Daniela; Flores, Verónica; Catriman, Sebastián; Falconaro, Antonella; Kabaradjian, Surpik; Luque, María L; Macedo, Beatriz; Molina, Juliana; Rauque, Carlos; Soto, Matías; Vázquez, Gabriela; Vega, Rocío; Viozzi, Gustavo

2017-01-01

Human relationship with dogs associates with numerous and varied benefits on human health; however, it also presents significant risks. The goal of this study was to describe demographic parameters and characteristics of dog ownership with possible implications on human health and to evaluate the prevalence of dog bites and traffic accidents due to dogs. Interviews were conducted in the neighborhoods of Nuestras Malvinas and Nahuel Hue in San Carlos de Bariloche. The percentage of homes with at least one dog, the average number of dogs per home, the prevalence of dog bites and traffic accidents due to dogs and the general awareness of the population on dog transmitted zoonoses were estimated. Regarding ownership characteristics, the degree of sterilization, vaccination and parasite control and the percentage of dogs allowed to roam freely in public places were evaluated. A total of 141 interviews were conducted; 87% of the households had at least one dog, with an average of 2.2 dogs. In 26% of the households someone had suffered a traffic accident caused by dogs and in 41% someone had been bitten. Antiparasite treatment was administered to 83% of the dogs in the last 12 months, on average 1.4 times (recommended 6 times), 51% were sterilized, 55% were allowed to roam freely. This study shows a disturbing situation regarding the canine population of the evaluated neighborhoods. The number of dogs allowed to roam freely and the low level of parasite control and sterilization provide suitable conditions for the spread of zoonoses.

Responsible ownership of dogs and human health in neighborhoods of San Carlos de Bariloche, Argentina

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Gilda Garibotti

2017-08-01

Full Text Available Human relationship with dogs associates with numerous and varied benefits on human health; however, it also presents significant risks. The goal of this study was to describe demographic parameters and characteristics of dog ownership with possible implications on human health and to evaluate the prevalence of dog bites and traffic accidents due to dogs. Interviews were conducted in the neighborhoods of Nuestras Malvinas and Nahuel Hue in San Carlos de Bariloche. The percentage of homes with at least one dog, the average number of dogs per home, the prevalence of dog bites and traffic accidents due to dogs and the general awareness of the population on dog transmitted zoonoses were estimated. Regarding ownership characteristics, the degree of sterilization, vaccination and parasite control and the percentage of dogs allowed to roam freely in public places were evaluated. A total of 141 interviews were conducted; 87% of the households had at least one dog, with an average of 2.2 dogs. In 26% of the households someone had suffered a traffic accident caused by dogs and in 41% someone had been bitten. Antiparasite treatment was administered to 83% of the dogs in the last 12 months, on average 1.4 times (recommended 6 times, 51% were sterilized, 55% were allowed to roam freely. This study shows a disturbing situation regarding the canine population of the evaluated neighborhoods. The number of dogs allowed to roam freely and the low level of parasite control and sterilization provide suitable conditions for the spread of zoonoses.

Evaluating two irrigation controllers under subsurface drip irrigated tomato crop

International Nuclear Information System (INIS)

Al-Ghobari, H.M.; Mohammad, F.S.; El Marazky, M.S.A.

2016-01-01

Smart systems could be used to improve irrigation scheduling and save water under Saudi Arabia’s present water crisis scenario. This study investigated two types of evapotranspiration-based smart irrigation controllers, SmartLine and Hunter Pro-C2, as promising tools for scheduling irrigation and quantifying plants’ water requirements to achieve water savings. The effectiveness of these technologies in reducing the amount of irrigation water was compared with the conventional irrigation scheduling method as a control treatment. The two smart irrigation sensors were used for subsurface irrigation of a tomato crop (cv. Nema) in an arid region. The results showed that the smart controllers significantly reduced the amount of applied water and increased the crop yield. In general, the Hunter Pro-C2 system saved the highest amount of water and produced the highest crop yield, resulting in the highest water irrigation efficiency compared with the SmartLine controller and the traditional irrigation schedule. It can be concluded that the application of advanced scheduling irrigation techniques such as the Hunter controller under arid conditions can realise economic benefits by saving large amounts of irrigation water.

Evaluating two irrigation controllers under subsurface drip irrigated tomato crop

Energy Technology Data Exchange (ETDEWEB)

Al-Ghobari, H.M.; Mohammad, F.S.; El Marazky, M.S.A.

2016-07-01

Smart systems could be used to improve irrigation scheduling and save water under Saudi Arabia’s present water crisis scenario. This study investigated two types of evapotranspiration-based smart irrigation controllers, SmartLine and Hunter Pro-C2, as promising tools for scheduling irrigation and quantifying plants’ water requirements to achieve water savings. The effectiveness of these technologies in reducing the amount of irrigation water was compared with the conventional irrigation scheduling method as a control treatment. The two smart irrigation sensors were used for subsurface irrigation of a tomato crop (cv. Nema) in an arid region. The results showed that the smart controllers significantly reduced the amount of applied water and increased the crop yield. In general, the Hunter Pro-C2 system saved the highest amount of water and produced the highest crop yield, resulting in the highest water irrigation efficiency compared with the SmartLine controller and the traditional irrigation schedule. It can be concluded that the application of advanced scheduling irrigation techniques such as the Hunter controller under arid conditions can realise economic benefits by saving large amounts of irrigation water.

Effect of Alternative Irrigation Strategies on Yield and Quality of Fiesta Raisin Grapes Grown in California

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Isabel Abrisqueta

2018-04-01

Full Text Available Traditionally, grapes are fully irrigated, but alternative irrigation strategies to reduce applied irrigation water may be necessary in the future as occurrences of drought increase. This study was conducted in the San Joaquin Valley (SJV of California from 2012 to 2014. Three irrigation treatments were used to study the effects on the yield and quality of Fiesta grapes. The treatments included: grower irrigation (GI weekly irrigation lasting for approximately 65 h; sustained deficit (SD equal to 80% of the GI treatment; and regulated deficit (RD equal to 50% of the GI until fruit set when it was increased to 80% of the GI through harvest and reduced to 50% of the GI after harvest. Average water use across treatments was ≈489 mm. Average yield across all treatments was 7.9 t ha−1, 9.1 t ha−1 and 11.8 t ha−1 in 2012, 2013, and 2014, respectively. Yield was sustained in SD and RD, with up to a 20% reduction in applied water use compared to GI. There were no differences in raisin quality and grade among any of the treatments in any year. The percentage of substandard grapes decreased from an average of 12.6% in 2012 to 3.6% in 2013 and 2014. Growers may use a sustained deficit approach during periods of limited water availability to minimize the effect on yield.

Diferencias innatas y desigualdades socio-espaciales de Calidad de Vida en San Carlos de Bariloche, Argentina = Innate differences and socio-spatial inequalities Quality of Life in San Carlos de Bariloche, Argentina

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Carlos Alberto Abaleron

2016-09-01

Full Text Available El propósito del artículo es mostrar cómo diferencias innatas de la población –sexo, edad y lugar de nacimiento- están altamente asociadas con las desigualdades socio-espaciales de Calidad de Vida (CdV de un grupo de barrios de San Carlos de Bariloche, Patagonia Norte de Argentina, entre la crisis económica de 1997 y la recuperación del 2005. El método principal del análisis está basado en el Enfoque integrado de la Pobreza (EIP que mide tanto la pobreza coyuntural (Líneas de Ingreso como la estructural (Necesidades Básicas Insatisfechas, NBI de la población de acuerdo a las mencionadas diferencias del jefe del hogar. Los resultados de las observaciones hechas arrojan, en general, mejoras en el acceso a bienes y servicios debido a ingresos más altos, y reducción en la tasa de desempleo. Sin embargo, esto es menos evidente en aquellos barrios muy pobres que en otros con ausencia de pobrezas, mayores ingresos, más ocupación plena, y altos niveles de instrucción de los jefes de hogares. La interpretación de estos resultados está basada en nuestro enfoque de CdV, el cuál reconoce al conocimiento o imagen del mundo como la principal capacidad para generar libertad de decisión –sujeta a valores y principios universales que nos dicen qué es justo, mejor y bueno- que permite a las personas, grupos y a la sociedad como un todo funcionar y ser. Por el contrario, lo sucedido en Bariloche muestra que la CdV no es la misma para todos, con la creación de verdaderos campos de desigualdades socio-espaciales, con grupos de personas auto encapsulados por decisión propia, simultáneamente con grupos encerrados por el poder de otros dentro de geografías degradadas, con nulos o escasos grados de libertad para oponerse.The purpose of the article is to show how innate differences such as sex, age and birthplace, are strongly associated with socio-spatial inequalities of Quality of Life (Q&L in a group of neighborhoods

Marcas urbanas y sentidos sociales en disputa. San Carlos de Bariloche, Argentina, 1966-1983

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Paula Gabriela Núñez

2013-07-01

Full Text Available San Carlos de Bariloche es la principal localidad turística de la Patagonia argentina. Representa, por su dimensión, a la ciudad más poblada de la provincia de Río Negro y es la tercera en tamaño en la Patagonia. Su crecimiento demográfico ha estado nutrido por diferentes migraciones nacionales y extranjeras. De estas últimas las principales provienen de países latinoamericanos. El artículo apunta a indagar en  la desvalorización de su migración más importante, la chilena, durante la segunda mitad del siglo XX. Esta exclusión se fortaleció entre 1966 y 1983, por las iniciativas estatales que exacerbaron la xenofobia, las persecuciones políticas, la precarización de las condiciones laborales y los cambios en la organización espacial durante los gobiernos dictatoriales del período, esto es, los que se desarrollaron de 1966 a 1973 y de 1976 a 1983. El presente artículo analiza cómo algunos espacios de Bariloche se constituyeron en marcas urbanas que representaron intereses de los sectores más visibles en nombre de la “nación”, al tiempo que revisa dispositivos de resistencia de sectores excluidos de migrantes chilenos, que tuvieron, paralelamente, componentes de construcción espacial. Para este último punto se aborda la construcción de la Capilla Nuestra Señora del Carmen en 1966, construida en el área conocida como “barrio de los chilenos”, que se levantó como una marca alternativa, tanto material como simbólica, para disputar pertenencia, reconocimiento y visibilidad.

Factores que inciden en el desarrollo de la responsabilidad social empresarial: estudio realizado en el sector hotelero de San Carlos, Costa Rica (Influence factors of the Enterprise's Social Responsibility Development: A case study of the hotel and tourism sector in San Carlos, Costa Rica.

Directory of Open Access Journals (Sweden)

José Martínez Villavicencio

2015-11-01

Full Text Available En los últimos años, las pequeñas, medianas y grandes empresas de Costa Rica han intensificado su interés en la Responsabilidad Social Empresarial (RSE, debido a que cada vez hay mayor urgencia para la sostenibilidad y sobrevivencia de la sociedad, así como que la actividad comercial asuma acciones de manera responsable e integral para el desarrollo del país. Este estudio tiene por objetivo identificar los factores impulsores de la RSE, identificados, específicamente, como “consumidores”, “proveedores”, “comunidad”, “medio ambiente”, “competitividad” y “financiamiento”, para formular modelos de gestión e indicadores de medición que puedan ejercer influencia y facilitar que una empresa sea responsable. Para esto se realizó un estudio de casos con dieciséis empresas hoteleras de la Fortuna de San Carlos y se aplicó una metodología cualitativa mediante una entrevista semiestructurada. Dentro de los resultados más importantes se encontró, como principal impulsor de RSE, a los “consumidores” y, en segunda instancia, al “ambiente”, mientras que se logró identificar que “proveedores” y “comunidad” no tienen mayor efecto como impulsores de RSE, información que permite apoyar la creación de políticas sociales y sostenibilidad turística a nivel regional.   Abstract: In the last years, small, medium and big companies from Costa Rica have intensified their interest in Corporate Social Responsibility (CSR. Given the sustainability and survival growing urgency in modern society, commercial activity assumes responsible and integral actions on the country development. The aim of this article is to identify the driving factors of CSR, which are, specifically, consumers, suppliers, community, environment, competitiveness and financing, to formulate management models and measurement indicators that could be used to influence and ease the responsible task of a

Utilisation de l'espace dans la communauté de San Juan

Directory of Open Access Journals (Sweden)

1975-01-01

Full Text Available Quelques aspects de la mise en valeur et de l'exploitation agro-pastorale du terroir de San Juan sont présentés à l'aide d'une série de cartes et de tableaux: carte de l'intensité de l'utilisation annuelle de la terre, circuit annuel du bétail, système foncier, évolution de l'irrigation au cours de l'année, rotation des cultures à proximité du village, rotation de terres d'altitude, évolution du bétail et enfin systèmes de mise en valeur du sol, on étudie en conclusion deux types d'évolution possibles de ce village. -Una serie de mapas y de cuadros presenta algunos aspectos del manejo y de 1a explotación agropastoral del terruño de la Comunidad de San Juan, teniendo en cuenta las limitaciones naturales ,y socioculturales: mapa de la intensidad del uso anual de la tierra con respecto al riego, rotación del ganado durante el año, sistema predial, evolución del riego a lo largo del año, rotación de los cultivos entre los corrales ubicados cerca del pueblo, rotación de los cultivos en las tierras de altura, evolución del ganado y sistemas de uso del suelo. Se examinan en conclusión dos tipos de evolución posibles para el pueblo. Some aspects of agro-pastoral management and exploitation in the San Juan lands are presented with a series of maps and tables: map of annual land utilization intensity, annual cattle rotation, land tenure system, irrigation process during the year, rotation of crops near the village, rotation of altitude lands, cattle evolution and soil use systems. Finally, two possible types of evolution for this village are discussed.

Los paisajes de Carlos V : primer viaje a España (1517-1518

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Pilar Bosqued Lacambra

2011-01-01

Full Text Available Laurent Vital escribió la Relación del primer viaje de Carlos V a España, que inició en 1517 cuando salió de Gante para embarcar en Flesinga y emprender por mar la travesía hasta España, donde llegó a Asturias. Durante el verano de aquel año Carlos V disfrutó del paisaje de su tierra natal y recorrió durante el primer mes del otoño una parte de la cornisa cantábrica, desde Villaviciosa hasta San Vicente de la Barquera. Siguiendo el relato, se analizan y describen los paisajes que recorrió y las situaciones y sensaciones que vivió a lo largo del mencionado trayecto, tanto en sus territorios flamencos como en tierras españolas, a las que vino para ser proclamado como rey.Laurent Vital wrote the report of the first journey of Carlos V to Spain, that started in 1517 when he departed from Ghent to embark in Vlissingen and undertake through sea the crossing until Spain, arriving in Asturias. During that year’s summer, Carlos V enjoyed the landscape of his native land and roamed part of the Cantabric coast during the first month of that year’s Autumn , from Villaviciosa to San Vicente de la Barquera. In the story, the landscapes that he travelled through were analysed and described as well as the situations and feelings that he lived during the mentioned travel through his Flemish territories and Spanish grounds to which he became appointed as king.

Condensation irrigation a system for desalination and irrigation

International Nuclear Information System (INIS)

Lindblom, J.; Nordell, B

2006-01-01

condensation irrigation is a system for both desalination and irrigation. The principles is that humidified air is let into an underground horizontal pipe system, where the air is cooled by the ground and humidity falls out as fresh water. The humidification could e.g. be achieved by evaporation of seawater in solar stills or any other heat source. By using drainage pipes for underground air transportation the water percolates into the soil, thereby irrigating the land. This study focuses on drinking water production, which means that humid air is led into plan pipes where the condensed water is collected at the pipe endings. Numerical simulations gave a study-state diurnal mean water production of 1.8 kg per meter of pipe over a 50 m pipe. Shorter pipes result in a greater mean production rate. Since the heat transfer of drainage pipes would be greater, current study indicates that condensation irrigation is a promising method for desalination and irrigation. Performed studies in condensation irrigation started at LTU in 2003. Current paper reports the initial theoretical work on the system.(Author)

Interparticle interactions and structure in nonideal solutions of human serum albumin studied by small-angle neutron scattering and Monte Carlo simulation

DEFF Research Database (Denmark)

Sjöberg, B.; Mortensen, K.

1994-01-01

of human serum albumin (HSA) up to a concentration of 0.26 g/cm(3) in 1.08 M NaCl. In order to obtain a model for the interactions we have combined the SANS data with results obtained by Monte Carlo simulations where we calculate the structure factor S(Q) and the pair correlation function g......Moderately or highly concentrated nonideal solutions of macromolecules are very important systems e.g. in biology and in many technical processes. In this work we have used the small-angle neutron scattering technique (SANS) to study the interactions and interparticle structure in solutions......(r). The advantage of using the Monte Carlo method is that completely general models for the particle shape and the interactions can be considered. It is found that the SANS data can be explained by a model where the shape of the HSA molecule is approximated by an ellipsoid of revolution with semiaxes a = 6.8 nm...

Review of ultrasonic irrigation in endodontics: increasing action of irrigating solutions

Science.gov (United States)

Mozo, Sandra; Llena, Carmen

2012-01-01

Introduction: Effective irrigant delivery and agitation are prerequisites for successful endodontic treatment. Ultrasonic irrigation can be performed with or without simultaneous ultrasonic instrumentation. Existing literature reveals that ultrasonic irrigation may have a very positive effect on chemical, biological and physical debridement of the root canal system as investigated in many in vitro studies. Objective: The purpose of this review article was to summarize and discuss the available information concerning ultrasonic irrigation in endodontics. Methods: This article presents an overview of ultrasonic irrigation methods and their debridement efficacy. In this paper the relevant literature on passive ultrasonic irrigation is reviewed. Information from original scientific papers or reviews listed in MEDLINE and Cochrane were included in the review. Results: The use of ultrasound in the irrigation procedure results in improved canal cleanliness, better irrigant transfer to the canal system, soft tissue debridement, and removal of smear layer and bacteria. There are many in vitro studies, but there is a need to standardize protocols, and correlate the clinical efficacy of ultrasonic devices with improved treatment outcomes. Understanding the basis of ultrasonic irrigation is fundamental for clinicians and researchers to improve the design and use of ultrasonic irrigation. Key words:Ultrasonic irrigation, ultrasound, smear layer, endodontics. PMID:22143738

Irrigation and Autocracy

DEFF Research Database (Denmark)

Bentzen, Jeanet Sinding; Kaarsen, Nicolai; Wingender, Asger Moll

We show that societies with a history of irrigation-based agriculture have been less likely to adopt democracy than societies with a history of rainfed agriculture. Rather than actual irrigation, the empirical analysis is based on how much irrigation potentially can increase yields.Irrigation pot...

Drip irrigation using a PLC based adaptive irrigation system

OpenAIRE

Shahidian, S.; Serralheiro, R. P.; Teixeira, J. L.; Santos, F. L.; Oliveira, M. R. G.; Costa, J. L.; Toureiro, C.; Haie, Naim; Machado, R. M.

2009-01-01

Most of the water used by man goes to irrigation. A major part of this water is used to irrigate small plots where it is not feasible to implement full-scale Evapotranspiration based irrigation controllers. During the growth season crop water needs do not remain constant and varies depending on the canopy, growth stage and climate conditions such as temperature, wind, relative humidity and solar radiation. Thus, it is necessary to find an economic irrigation controller that can adapt the dail...

Normas de control interno recogidas en el reglamento de la dirección del giro del Banco de San Carlos (1789

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Francisco Mayordomo García-Chicote

2009-12-01

Full Text Available En el Reglamento de la Dirección del Giro, de 1789, se resumieron todas las disposiciones relativas a esta sección del Banco de San Carlos emitidas con posterioridad a la publicación de su Real Cédula fundacional de 1782; observándose en dicho Reglamento que en él se abordaron los aspectos básicos del control interno, tales como, la asignación de funciones y su reparto entre el personal, el establecimiento de normas y procedimientos operativos, describiendo las funciones del personal de correspondencia y de libros, y el detalle las tareas de autorización, ejecución, registro y custodia confiadas a dicho personal; de lo cual se deduce que los objetivos de esta norma —como los de cualquier manual de control interno— fueron los de optimizar la gestión de la Dirección del Giro, prevenir errores en sus registros contables y conferir fiabilidad a la información final que se derivaba de ellos, así como la protección de los activos vinculados a esta Dirección.

ROOT CANAL IRRIGANTS AND IRRIGATION TECHNIQUES: A REVIEW

OpenAIRE

Aniketh; Mohamed; Geeta; Nandakishore; Gourav Kumar; Patrick Timothy; Jayson Mathew; Sahle Abdul

2015-01-01

Root canal irrigation is not much emphasised in endodontic therapy. Most articles discussed are on root canal shaping and obturation not much emphasis is given for irrigation. There are many irrigation solutions which are introduced into market. The primary objective of root canal therapy is the ret ention of the pulpless or pulpally involved tooth with its associated periapical tissues in a healthy state. Achievement of this objective requires that the pulpal spaces and con...

Analysis of Irrigation Water Quality at Kadawa Irrigation Project for Improved Productivity

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AR Sanda

2014-09-01

Full Text Available In the face of water scarcity and the several negative consequences, such as water wastage, flooding, water logging, soil losses and production losses, conserving the finite amount of fresh water is a must. The quality of irrigation water must therefore be ascertained. The chemical quality of three sources of irrigation water from canal and drainage water, namely drainage water, fresh irrigation water from canal, and drainage/irrigation water mixture, were analyzed from Kadawa irrigation Project for year 2013 and 2014 cropping seasons, with the view to evaluating the potential risks associated with their use in irrigation and hence their suitability or otherwise for irrigation purposes. The analysis revealed that the use of drainage water alone for irrigation may result in problems associated with salinity, while a blend of drainage/irrigation water in the ratio of 1:1 is a viable means of water conservation and a good means of crop production. DOI: http://dx.doi.org/10.3126/ije.v3i3.11082 International Journal of Environment Vol.3(3 2014: 235-240

Green and blue water footprint reduction in irrigated agriculture: effect of irrigation techniques, irrigation strategies and mulching

Science.gov (United States)

Chukalla, A. D.; Krol, M. S.; Hoekstra, A. Y.

2015-12-01

Consumptive water footprint (WF) reduction in irrigated crop production is essential given the increasing competition for freshwater. This study explores the effect of three management practices on the soil water balance and plant growth, specifically on evapotranspiration (ET) and yield (Y) and thus the consumptive WF of crops (ET / Y). The management practices are four irrigation techniques (furrow, sprinkler, drip and subsurface drip (SSD)), four irrigation strategies (full (FI), deficit (DI), supplementary (SI) and no irrigation), and three mulching practices (no mulching, organic (OML) and synthetic (SML) mulching). Various cases were considered: arid, semi-arid, sub-humid and humid environments in Israel, Spain, Italy and the UK, respectively; wet, normal and dry years; three soil types (sand, sandy loam and silty clay loam); and three crops (maize, potato and tomato). The AquaCrop model and the global WF accounting standard were used to relate the management practices to effects on ET, Y and WF. For each management practice, the associated green, blue and total consumptive WF were compared to the reference case (furrow irrigation, full irrigation, no mulching). The average reduction in the consumptive WF is 8-10 % if we change from the reference to drip or SSD, 13 % when changing to OML, 17-18 % when moving to drip or SSD in combination with OML, and 28 % for drip or SSD in combination with SML. All before-mentioned reductions increase by one or a few per cent when moving from full to deficit irrigation. Reduction in overall consumptive WF always goes together with an increasing ratio of green to blue WF. The WF of growing a crop for a particular environment is smallest under DI, followed by FI, SI and rain-fed. Growing crops with sprinkler irrigation has the largest consumptive WF, followed by furrow, drip and SSD. Furrow irrigation has a smaller consumptive WF compared with sprinkler, even though the classical measure of "irrigation efficiency" for furrow

Root canal irrigants

OpenAIRE

Kandaswamy, Deivanayagam; Venkateshbabu, Nagendrababu

2010-01-01

Successful root canal therapy relies on the combination of proper instrumentation, irrigation, and obturation of the root canal. Of these three essential steps of root canal therapy, irrigation of the root canal is the most important determinant in the healing of the periapical tissues. The primary endodontic treatment goal must thus be to optimize root canal disinfection and to prevent reinfection. In this review of the literature, various irrigants and the interactions between irrigants are...

La leyenda madrileña del reloj de las monjas de San Plácido y el Semanario Pintoresco Español

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Labrador Ben, Julia M.ª

2012-10-01

Full Text Available Many researchers and writers have written about the legend of the Monastery de la Encarnación, formerly the convent of San Plácido, starting, in many cases, with the text published by Carlos García Doncel in the Semanario Pintoresco Español . The sect of the Illuminati, the convent’s “possessed”, Felipe IV’s love affair with the novice Margarita, and the clock that the King bought her as a present, which sounded a death knell each quarter, are the core narrative elements of the legend of the clock of San Plácido.El madrileño Monasterio de la Encarnación, antes Convento de San Plácido, ha hecho correr ríos de tinta tanto por parte de investigadores como de numerosos literatos que partieron, en muchos casos, del texto publicado en el Semanario Pintoresco Español, escrito por Carlos García Doncel. La secta de los iluminati, las endemoniadas del convento, los amores de Felipe IV con la novicia Margarita y el reloj que regaló el Rey, que durante todos los cuartos sonaba a toque de difuntos, son los elementos narrativos nucleares de la leyenda del reloj de San Plácido.

Quantifying runoff water quality characteristics from nurseries and avocado groves subjected to altered irrigation and fertilizer regimes

Science.gov (United States)

Samant, S. A.; Beighley, R. E.

2007-12-01

In agriculture, improper, excessive or poorly timed irrigation and fertilizer applications can result in increased pollutants in runoff and degraded water quality. Specifically, the cultivation of salt sensitive plants and nurseries require significant irrigation and fertilizer that leads to high nutrient leaching. In southern California, a large producer of Avocados and nursery plant, waterways are often subjected to elevated nutrient concentrations, which stress the aquatic ecosystem. In this research, the specific objectives are to determine optimal irrigation and fertilizer application rates for minimizing nutrient and sediment export from avocado groves and nurseries. Altered irrigation and fertilizer application experiments will be implemented and monitored at the San Diego State University's Santa Margarita Ecological Reserve, which contains a 12 ha avocado grove and newly constructed 0.4 ha nursery. The study will last for twelve months, with runoff from natural rainfall or irrigation sampled and analyzed for nutrient concentrations on a monthly basis. The growth rate, leaf nutrient content and plant yield will also be monitored monthly. The nursery site is divided into eight plots (13.5-m x 13.5-m), with each plot containing 1200 plants consisting of four commonly used landscaping varieties in southern California. The avocado grove of the Hass variety is divided into four 1-ha plots. The experimental plots represent combinations of irrigation and fertilization practices with different methods and rates. In all cases, irrigation is fully automated based on soil moisture. To assess the effectiveness of the altered irrigation and fertilizer strategies, runoff water quality and plant yield will be compared to controlled treatments. This research is intended to provide a better understanding of how irrigation and fertilizer management can be used for the long-term reduction of nutrients in the Santa Margarita Watershed, which in turn will lead to improved

Factors affecting irrigant extrusion during root canal irrigation: a systematic review

NARCIS (Netherlands)

Boutsioukis, C.; Psimma, Z.; van der Sluis, L.W.M.

2013-01-01

The aim of the present study was to conduct a systematic review and critical analysis of published data on irrigant extrusion to identify factors causing, affecting or predisposing to irrigant extrusion during root canal irrigation of human mature permanent teeth. An electronic search was conducted

Significados en torno a la reparación, la ayuda humanitaria, la indemnización y la restitución en víctimas del conflicto armado en el municipio de San Carlos

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Juan David Villa Gómez

2015-08-01

Full Text Available Se presentan los primeros resultados de las indagaciones sobre la valoración que las mismas víctimas del conflicto armado, del municipio de San Carlos Antioquia (Colombia, hacen de la implementación de la Ley 1448 (Ley de Victimas; dicho proceso de investigación, en esta primera entrega, evidenció entre otros hallazgos, la contradicción entre el discurso oficial y el relato de las víctimas en relación a los procesos de reparación, discursos contradictorios respecto a la transición, el estado de vulneración e insatisfacción de necesidades básicas de las personas victimizadas así como una alta confusión en la implementación de la Ley. Estos resultados, entre otros, permiten afirmar que, la reparación hoy, dista mucho de ser un proceso que aporte a la reconstrucción del tejido social, a la paz y la reconciliación. The first results of the inquiries on the valuation made by the very victims of the armed conflict, in the municipality of San Carlos Antioquia (Colombia are shown in this paper, which are part of the implementation of the 1448 Law (Law of Victims; such a research process of, in this first installment, evidenced among other findings, the contradiction between the official discourse and the story of the victims in relation to the reparation processes, contradictory speeches regarding the transition, the state of infringement and dissatisfaction of victimized people’s basic needs, as well as a high confusion as for the implementation of the Law. These findings, among others, allow to affirm that reparation today, is far from being a process that contributes to the reconstruction of the social fabric, to peace, and reconciliation.

Characterization of the hydrologic resources of San Miguel County, New Mexico, and identification of hydrologic data gaps, 2011

Science.gov (United States)

Matherne, Anne Marie; Stewart, Anne M.

2012-01-01

The U.S. Geological Survey (USGS), in cooperation with San Miguel County, New Mexico, conducted a study to assess publicly available information regarding the hydrologic resources of San Miguel County and to identify data gaps in that information and hydrologic information that could aid in the management of available water resources. The USGS operates four continuous annual streamgages in San Miguel County. Monthly discharge at these streamgages is generally bimodally distributed, with most runoff corresponding to spring runoff and to summer monsoonal rains. Data compiled since 1951 on the geology and groundwater resources of San Miguel County are generally consistent with the original characterization of depth and availability of groundwater resources and of source aquifers. Subsequent exploratory drilling identified deep available groundwater in some locations. Most current (2011) development of groundwater resources is in western San Miguel County, particularly in the vicinity of El Creston hogback, the hogback ridge just west of Las Vegas, where USGS groundwater-monitoring wells indicate that groundwater levels are declining. Regarding future studies to address identified data gaps, the ability to evaluate and quantify surface-water resources, both as runoff and as potential groundwater recharge, could be enhanced by expanding the network of streamgages and groundwater-monitoring wells throughout the county. A series of seepage surveys along the lengths of the rivers could help to determine locations of surface-water losses to and gains from the local groundwater system and could help to quantify the component of streamflow attributable to irrigation return flow; associated synoptic water-quality sampling could help to identify potential effects to water quality attributable to irrigation return flow. Effects of groundwater withdrawals on streamflow could be assessed by constructing monitoring wells along transects between production wells and stream reaches

Sustainable management after irrigation system transfer : experiences in Colombia - the RUT irrigation district

NARCIS (Netherlands)

Urrutia Cobo, N.

2006-01-01

Colombiais a tropical country located in South America. It has a total area of 114 million ha. In Colombia two irrigation sectors are distinguished: the small-scale irrigation and the large-scale irrigation sector. The small-scale irrigation sector is developed on lands

Quantifying anthropogenic contributions to century-scale groundwater salinity changes, San Joaquin Valley, California, USA

Science.gov (United States)

Hansen, Jeffrey; Jurgens, Bryant; Fram, Miranda S.

2018-01-01

Total dissolved solids (TDS) concentrations in groundwater tapped for beneficial uses (drinking water, irrigation, freshwater industrial) have increased on average by about 100 mg/L over the last 100 years in the San Joaquin Valley, California (SJV). During this period land use in the SJV changed from natural vegetation and dryland agriculture to dominantly irrigated agriculture with growing urban areas. Century-scale salinity trends were evaluated by comparing TDS concentrations and major ion compositions of groundwater from wells sampled in 1910 (Historic) to data from wells sampled in 1993-2015 (Modern). TDS concentrations in subregions of the SJV, the southern (SSJV), western (WSJV), northeastern (NESJV), and southeastern (SESJV) were calculated using a cell-declustering method. TDS concentrations increased in all regions, with the greatest increases found in the SSJV and SESJV. Evaluation of the Modern data from the NESJV and SESJV found higher TDS concentrations in recently recharged (post-1950) groundwater from shallow (soil amendments combined. Bicarbonate showed the greatest increase among major ions, resulting from enhanced silicate weathering due to recharge of irrigation water enriched in CO2 during the growing season. The results of this study demonstrate that large anthropogenic changes to the hydrologic regime, like massive development of irrigated agriculture in semi-arid areas like the SJV, can cause large changes in groundwater quality on a regional scale.

Irrigation Training Manual. Planning, Design, Operation, and Management of Small-Scale Irrigation Systems [and] Irrigation Reference Manual. A Technical Reference to Be Used with the Peace Corps Irrigation Training Manual T0076 in the Selection, Planning, Design, Operation, and Management of Small-Scale Irrigation Systems.

Science.gov (United States)

Salazar, LeRoy; And Others

This resource for trainers involved in irrigated agriculture training for Peace Corps volunteers consists of two parts: irrigation training manual and irrigation reference manual. The complete course should fully prepare volunteers serving as irrigation, specialists to plan, implement, evaluate and manage small-scale irrigation projects in arid,…

An Integrated Modeling System for Water Resource Management Under Climate Change, Socio-Economic Development and Irrigation Management

Science.gov (United States)

SU, Q.; Karthikeyan, R.; Lin, Y.

2017-12-01

Water resources across the world have been increasingly stressed in the past few decades due to the population and economic growth and climate change. Consequently, the competing use of water among agricultural, domestic and industrial sectors is expected to be increasing. In this study, the water stresses under various climate change, socio-economic development and irrigation management scenarios are predicted over the period of 2015-2050 using an integrated model, in which the changes in water supply and demand induced by climate change, socio-economic development and irrigation management are dynamically parameterized. Simulations on the case of Texas, Southwest U.S. were performed using the newly developed integrated model, showing that the water stress is projected to be elevated in 2050 over most areas of Texas, particularly at Northern and Southern Plain and metropolitan areas. Climate change represents the most pronounce factor affecting the water supply and irrigation water demand in Texas. The water supply over East Texas is largely reduced in future because of the less precipitation and higher temperature under the climate change scenario, resulting in an elevated irrigation water demand and thus a higher water stress in this region. In contrast, the severity of water shortage in West Texas would be alleviated in future because of climate change. The water shortage index over metropolitan areas would increase by 50-90% under 1.0% migration scenario, suggesting that the population growth in future could also greatly stress the water supply, especially megacities like Dallas, Houston, Austin and San Antonio. The projected increase in manufacturing water demand shows little effects on the water stress. Increasing irrigation rate exacerbates the water stress over irrigated agricultural areas of Texas.

Effect of Climate Extremes, Seasonal Change, and Agronomic Practices on Measured Evapotranspiration and CO2 Exchange in Sacramento-San Joaquin River Delta Alfalfa Fields

Science.gov (United States)

Clay, J.; Kent, E. R.; Leinfelder-Miles, M.; Paw U, K. T.; Little, C.; Lambert, J. J.

2017-12-01

Evapotranspiration and CO2 exchange was measured in five alfalfa fields in the Sacramento-San Joaquin River Delta region from 2016 to 2017 using eddy covariance and surface renewal methods. Seasonal changes of evapotranspiration and CO2 fluxes were compared between 2016, a drought year, and 2017, a high rainfall year. Additionally, changes in evapotranspiration and CO2 flux were investigated across various agronomic considerations, such as irrigation methods (border-check flood and sub-surface), stand life, and herbicide programs. Components of the energy balance, including net radiation, latent heat, ground heat flux, and sensible heat, were evaluated considering correlations to wind speed measured by three sonic anemometers, irrigation frequency, and crop cutting cycle. Comparisons between two different types of radiometers were also carried out. Under drought conditions, we observed higher amounts of evapotranspiration in a field having a stand life of less than two years of age compared to older stands, and in a sub-surface irrigated field compared to flood irrigated fields.

A dynamic model of soil salinity and drainage generation in irrigated agriculture: A framework for policy analysis

Science.gov (United States)

Dinar, Ariel; Aillery, Marcel P.; Moore, Michael R.

1993-06-01

This paper presents a dynamic model of irrigated agriculture that accounts for drainage generation and salinity accumulation. Critical model relationships involving crop production, soil salinity, and irrigation drainage are based on newly estimated functions derived from lysimeter field tests. The model allocates land and water inputs over time based on an intertemporal profit maximization objective function and soil salinity accumulation process. The model is applied to conditions in the San Joaquin Valley of California, where environmental degradation from irrigation drainage has become a policy issue. Findings indicate that in the absence of regulation, drainage volumes increase over time before reaching a steady state as increased quantities of water are allocated to leaching soil salts. The model is used to evaluate alternative drainage abatement scenarios involving drainage quotas and taxes, water supply quotas and taxes, and irrigation technology subsidies. In our example, direct drainage policies are more cost-effective in reducing drainage than policies operating indirectly through surface water use, although differences in cost efficiency are relatively small. In some cases, efforts to control drainage may result in increased soil salinity accumulation, with implications for long-term cropland productivity. While policy adjustments may alter the direction and duration of convergence to a steady state, findings suggest that a dynamic model specification may not be necessary due to rapid convergence to a comon steady state under selected scenarios.

Use of ground-water reservoirs for storage of surface water in the San Joaquin Valley, California

Science.gov (United States)

Davis, G.H.; Lofgren, B.E.; Mack, Seymour

1964-01-01

The San Joaquin Valley includes roughly the southern two-thirds of the Central Valley of California, extending 250 miles from Stockton on the north to Grapevine at the foot of the Tehachapi Mountains. The valley floor ranges in width from 25 miles near Bakersfield to about 55 miles near Visalia; it has a surface area of about 10,000 square miles. More than one-quarter of all the ground water pumped for irrigation in the United States is used in this highly productive valley. Withdrawal of ground water from storage by heavy pumping not only provides a needed irrigation water supply, but it also lowers the ground-water level and makes storage space available in which to conserve excess water during periods of heavy runoff. A storage capacity estimated to be 93 million acre-feet to a depth of 200 feet is available in this ground-water reservoir. This is about nine times the combined capacity of the existing and proposed surface-water reservoirs in the San Joaquin Valley under the California Water Plan. The landforms of the San Joaquin Valley include dissected uplands, low plains and fans, river flood plains and channels, and overflow lands and lake bottoms. Below the land surface, unconsolidated sediments derived from the surrounding mountain highlands extend downward for hundreds of feet. These unconsolidated deposits, consisting chiefly of alluvial deposits, but including some widespread lacustrine sediments, are the principal source of ground water in the valley. Ground water occurs under confined and unconfined conditions in the San Joaquin Valley. In much of the western, central, and southeastern parts of the valley, three distinct ground-water reservoirs are present. In downward succession these are 1) a body of unconfined and semiconfined fresh water in alluvial deposits of Recent, Pleistocene, and possibly later Pliocene age, overlying the Corcoran clay member of the Tulare formation; 2) a body of fresh water confined beneath the Corcoran clay member, which

Quantitative microbial risk assessment for spray irrigation of dairy manure based on an empirical fate and transport model

Science.gov (United States)

Burch, Tucker R; Spencer, Susan K.; Stokdyk, Joel; Kieke, Burney A; Larson, Rebecca A; Firnstahl, Aaron; Rule, Ana M; Borchardt, Mark A.

2017-01-01

BACKGROUND: Spray irrigation for land-applying livestock manure is increasing in the United States as farms become larger and economies of scale make manure irrigation affordable. Human health risks from exposure to zoonotic pathogens aerosolized during manure irrigation are not well understood. OBJECTIVES: We aimed to a) estimate human health risks due to aerosolized zoonotic pathogens downwind of spray-irrigated dairy manure; and b) determine which factors (e.g., distance, weather conditions) have the greatest influence on risk estimates. METHODS: We sampled downwind air concentrations of manure-borne fecal indicators and zoonotic pathogens during 21 full-scale dairy manure irri- gation events at three farms. We fit these data to hierarchical empirical models and used model outputs in a quantitative microbial risk assessment (QMRA) to estimate risk [probability of acute gastrointestinal illness (AGI)] for individuals exposed to spray-irrigated dairy manure containing Campylobacter jejuni, enterohemorrhagic Escherichia coli (EHEC), or Salmonella spp. RESULTS: Median risk estimates from Monte Carlo simulations ranged from 10−5 to 10−2 and decreased with distance from the source. Risk estimates for Salmonella or EHEC-related AGI were most sensitive to the assumed level of pathogen prevalence in dairy manure, while risk estimates for C. jejuni were not sensitive to any single variable. Airborne microbe concentrations were negatively associated with distance and positively associated with wind speed, both of which were retained in models as a significant predictor more often than relative humidity, solar irradiation, or temperature. CONCLUSIONS: Our model-based estimates suggest that reducing pathogen prevalence and concentration in source manure would reduce the risk of AGI from exposure to manure irrigation, and that increasing the distance from irrigated manure (i.e., setbacks) and limiting irrigation to times of low wind speed may also reduce risk.

New Concept of Cultivation Using Limited Strip-Tillage with Strip Shallow Irrigation

Directory of Open Access Journals (Sweden)

Yazid Ismi Intara

2014-04-01

Full Text Available Normal 0 false false false IN X-NONE X-NONE Dry land is one of land resources which potentially used for food crop cultivation, especially in the areas which have light to medium technical obstacles. The development of technology to improve soil quality in marginal lands to be productive lands is still widely open for agricultural development in Indonesia. Rooting medium quality can be improved by changing soil tillage method and observing the proper crop irrigation technology. It can be the solution for crop cultivation in clay loam soil. This study aimed to obtain water movement model in a minimally-tilled clay soil with strip shallow irrigation. The concept is limited soil-tillage with strip shallow irrigation method, water supply technique, and crop water requirement. Method used in this study includes developing water movement model (software development in a minimally-tilled clay soil with subsurface irrigation. In the final stages, research also conducted water movement analysis testing apparatus in the laboratory, field validation of the subsurface irrigation performance, and cultivation technique testing to chili pepper growth (Capsicum annuumL.. The development of water movement simulation on a limited strip-tillage with subsurface irrigation uses the concept to quantify the amount of water in the soil. The analysis of movement pattern was demonstrated on contour patterns. It showed that the wetting process can reach depth zone – 5 cm to the rooting zone. It was an important discovery on the development of minimum stripe tillage soil with subsurface irrigation. Specifically, it can be concluded that: the result of fitting by eyes to diffusivity graphic and water content obtained the required parameter values for soil physical properties. It was then simulated on horizontal water movement model on a minimum strip-tillage with strip shallow irrigation /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso

San Francisco folio, California, Tamalpais, San Francisco, Concord, San Mateo, and Haywards quadrangles

Science.gov (United States)

Lawson, Andrew Cowper

1914-01-01

The five sheets of the San Francisco folio the Tamalpais, Ban Francisco, Concord, Ban Mateo, and Haywards sheets map a territory lying between latitude 37° 30' and 38° and longitude 122° and 122° 45'. Large parts of four of these sheets cover the waters of the Bay of San Francisco or of the adjacent Pacific Ocean. (See fig. 1.) Within the area mapped are the cities of San Francisco, Oakland, Berkeley, Alameda, Ban Rafael, and San Mateo, and many smaller towns and villages. These cities, which have a population aggregating about 750,000, together form the largest and most important center of commercial and industrial activity on the west coast of the United States. The natural advantages afforded by a great harbor, where the railways from the east meet the ships from all ports of the world, have determined the site of a flourishing cosmopolitan, commercial city on the shores of San Francisco Bay. The bay is encircled by hilly and mountainous country diversified by fertile valley lands and divides the territory mapped into two rather contrasted parts, the western part being again divided by the Golden Gate. It will therefore be convenient to sketch the geographic features under four headings (1) the area east of San Francisco Bay; (2) the San Francisco Peninsula; (3) the Marin Peninsula; (4) San Francisco Bay. (See fig. 2.)

The Temporal Variation of Leaf Water Potential in Pistachio under Irrigated and Non-Irrigated Conditions

Directory of Open Access Journals (Sweden)

Yusuf AYDIN

2014-09-01

Full Text Available The present study was carried out in the experimental field of Pistachio Research Institute on pistachio trees which has uzun variety that was 30 years old. The aim of this research was to determine the Leaf Water Potential (LWP of Pistacia vera L. under irrigated and non-irrigated conditions. In the study, the leaf water potential of pistachio was investigated under fully irrigated and non irrigated conditions. The leaf water potential values were measured one day before and after irrigation by using pressure chamber technique at the beginning, mid and end of irrigation season. According to the results obtained from measurements, the LWP value at the beginning of the irrigation season was -3.7 MPa at noon time due to relatively high temperature for both treatments. At the time of pre-dawn and sunset, this value increased and reached to - 1.6 MPa due to relatively low temperature. In general, the LWP values during the mid of irrigation season, in the irrigated treatments, reached to almost -2.5 MPa in the non-irrigated treatment and the value was measured as -3.68 MPa.

Effect of low-cost irrigation methods on microbial contamination of lettuce irrigated with untreated wastewater

DEFF Research Database (Denmark)

Keraita, Bernard; Konradsen, Flemming; Drechsel, P.

2007-01-01

OBJECTIVE: To assess the effectiveness of simple irrigation methods such as drip irrigation kits, furrow irrigation and use of watering cans in reducing contamination of lettuce irrigated with polluted water in urban farming in Ghana. METHODS: Trials on drip kits, furrow irrigation and watering...... cans were conducted with urban vegetable farmers. Trials were arranged in a completely randomised block design with each plot having all three irrigation methods tested. This was conducted in both dry and wet seasons. Three hundred and ninety-six lettuce, 72 soil, 15 poultry manure and 32 water samples...... were analysed for thermotolerant coliforms and helminth eggs. RESULTS: Lettuce irrigated with drip kits had the lowest levels of contamination, with, on average, 4 log units per 100 g, fewer thermotolerant coliforms than that irrigated with watering cans. However, drip kits often got clogged, required...

IRRIGATION USING SOLAR PUMP

OpenAIRE

Prof. Nitin P.Choudhary*1 & Ms. Komal Singne2

2017-01-01

In this report the described design of a PV and soil moisture sensor based automated irrigation system is introduced. This project aims to provide a human friendly, economical and automated water pumping system which eliminates the problems of over irrigation and helps in irrigation water optimization and manage it in accordance with the availability of water. Our project not only tries to modernize the irrigation practices and ensure the optimum yield by carefully fulfilling the requirements...

Contribution to the improvement of irrigation management practices through water - deficit irrigation

International Nuclear Information System (INIS)

Bazza, M.

1995-01-01

The study aimed at identifying irrigation management practices which could result in water savings through -water deficit irrigation. Two field experiments, one on wheat and the other on sugar beet, were conducted and consisted of refraining from supplying water during specific stages of the cycle so as to identy the period(s) during which water deficit would have a limited effect on crop production. In the case of wheat, high water deficit occurred during the early and during these stages was the most beneficial for the crop. However, one water application during the tillering stage allowed the yield to be lower only to that of the treatement with three irrigations. Irrigation during the stage of grain filling caused the kernel weight to be as high as under three irrigations. The lowest value corresponded to the treatement with one irrigation during grain filling and that under rainfed conditions. For sugar beet, when water stress was was applied early in the crop cycle, its effect could be almost entirely recovered with adequate watering during the rest of the growing season. On the opposite, good watering early in cycle, followed by a stress, resulted in the second lowest yield. Water deficit during the maturity stage had also a limited effect on yield. The most crucial periods for adequate watering were which correspond to late filiar development and root growth which coincided with the highest water requirements period. For the same amount of water savings through deficit irrigation, it was better to partition the stress throughout the cycle than during the critical stages of the crop. However, at the national level, it would have been more important to practice deficit irrigation and the irrigated area. For both crops, high yields as high as water - use efficiency values could have been obtained. 8 tabs; 5 refs ( Author )

Automation of irrigation systems to control irrigation applications and crop water use efficiency

Science.gov (United States)

Agricultural irrigation management to slow water withdrawals from non-replenishing quality water resources is a global endeavor and vital to sustaining irrigated agriculture and dependent rural economies. Research in site-specific irrigation management has shown that water use efficiency, and crop p...

Ghana - Agriculture - Irrigation

Data.gov (United States)

Millennium Challenge Corporation — The Millennium Development Authority (MiDA) financed the construction of a new irrigation scheme in Kpong and the renovation of two irrigation schemes in Botanga and...

Formación y pronóstico del precio diario de la energía eléctrica en la cadena Nare-Guatapé-San Carlos

Directory of Open Access Journals (Sweden)

Alejandro Romero

2003-01-01

Full Text Available Este trabajo plantea tres tipos de metodologías para la comprensión y pronóstico de los precios diarios de la energía eléctrica de la cadena Nare-Guatapé-San Carlos: modelo lineal multivariado, modelo autorregresivo determinístico y descomposición en series de Fourier. El precio de la energía eléctrica de una central depende no solamente del nivel del embalse y del caudal del río propio, sino también del embalse y sus respectivos afluentes aguas abajo o aguas arriba. En cuanto al pronóstico de los precios estos se pueden modelar con un proceso autorregreviso. El pronóstico sigue la tendencia y captura de los precios con aceptable precisión, especialmente para los valores máximos debido a los bajos caudales y volúmenes de embalse y teniendo en cuenta la variabilidad del precio para embalses de regulación diaria, semanal y mensual.

Demanda de irrigação da cultura da uva na Bacia do Rio São Francisco Irrigation demand for grape crop in San Francisco River Basin

Directory of Open Access Journals (Sweden)

Wallisson da S. Freitas

2006-09-01

Full Text Available Visando subsidiar o planejamento de projetos agrícolas para o dimensionamento de projetos de irrigação e a gestão de recursos hídricos, estimou-se e se espacializou a demanda de irrigação da videira (Vitis vinifera L., cv. Itália, na bacia do Rio São Francisco. Utilizaram-se séries históricas de dados de 81 estações climáticas distribuídas na bacia. Para cada estação calculou-se os valores, máximos diários e o total anual, da evapotranspiração de referência (ETo, da evapotranspiração da cultura (ETc, da demanda suplementar da cultura e da demanda suplementar de irrigação (este com eficiência de 70%. Com base nos resultados obtidos, concluiu-se que: (a a ETc máxima diária variou, em grande parte da bacia, de 4,5 a 5,7 mm d-1, tendo média anual de 943 mm; (b em média, a demanda anual suplementar da cultura foi 839,5 mm, equivalente a 103,5 mm inferior à ETc; (c o fato do sistema funcionar com 70% de eficiência, em vez de 90%, implica em acréscimo estimado de 18.808.755 m³ de água por ano, somente nas microrregiões de Juazeiro, BA e Petrolina, PE.The irrigation water demand of the grapevine (Vitis vinifera L. cv. Italy was estimated and spatialized in San Francisco River Basin, in order to subsidize the agricultural project planning and water resource management. Historical data series relative to 81 climatic stations distributed throughout the basin were used. The maximum daily values and the annual total values of the reference evapotranspiration (ETo, crop evapotranspiration (ETc, supplementary demand of the crop and the supplementary irrigation demand (70% efficiency were calculated for each station. According to the results, the following conclusions were drawn: (a in a large area of the basin, the maximum daily ETc varied from 4.5 to 5.7 mm d-1, with an annual mean of 943 mm; (b the supplementary annual demand of the crop averaged 839.5 mm, corresponding to 103.5 mm less than ETc; and (c the irrigation

Traditional Irrigation Management in Betmera-Hiwane, Ethiopia: The Main Peculiarities for the Persistence of Irrigation Practices

Institute of Scientific and Technical Information of China (English)

Solomon Habtu; Kitamura Yoshinobu

2006-01-01

Traditional irrigation, as part of the ancient agricultural practices in northern Ethiopia (Tigray), has persisted for long time since 500 B.C.,while many newly introduced irrigation projects have usually failed there. The main objective of this study is thus to investigate the peculiarities pertinent to irrigation management and those having contributed for the persistence of traditional irrigation practices for a long period of time. The experience gained from such areas can definitely help make irrigation management system of new irrigation schemes sustainable. Betmera-Hiwane, one of the ancient traditional irrigation areas in Tigray region, was selected for the field study. Direct observations through field visits accompanied by interviews to farmers, local officials, local knowledgeable individuals and higher officials were made. After analyzing the collected primary and secondary information, the main peculiarities that contributed to the persistence of traditional irrigation areas were identified, and they are: the presence of communally constructed local rules, locally designed hydraulic control structures, ownership feeling of the irrigators and accountability of water distributors to the irrigation management, the culture for mobilizing communal resources and the culture of self-initiating local water management strategies.

Modernized Irrigation Technologies in West Africa

Directory of Open Access Journals (Sweden)

Hakan Büyükcangaz

2017-12-01

Full Text Available Crop production in West Africa is mostly dependent upon rainfed agriculture. Irrigation is a vital need due to uneven distribution of rainfall and seasonality of water resources. However, management and sustainability of irrigation are under risk due to notably weak database, excessive cost, unappropriate soil or land use, environmental problems and extreme pessimism in some quarters since rainfed agriculture is seen as potentially able to support the present population. This paper focuses on modernized irrigation technologies and systems that utilize less water. Information about irrigation systems in Ghana and Liberia were gathered through: 1 Irrigation development authorities in both countries, by reviewing past literatures, online publications, reports and files about irrigation in West Africa, specifically Ghana and Liberia; 2 International Food Policy Research Institute (IFPRI; 3 Collation of information, reports and data from Ghana Irrigation Development Authority (GIDA and 4 International Water Management Institute (IWMI. The result shows that both countries have higher irrigation potential. However, the areas developed for irrigation is still a small portion as compare to the total land available for irrigation. On the other hand, as seen in the result, Liberia as compare to Ghana has even low level of irrigation development.

Irrigation in endodontic treatment.

Science.gov (United States)

Basrani, Bettina

2011-01-01

The primary endodontic treatment goal is to optimize root canal disinfection and to prevent reinfection. Successful root canal therapy relies on the combination of proper instrumentation, irrigation, and obturation of the root canal system. In this review of the literature, various irrigants and the interactions between irrigants are discussed and new delivery systems are introduced.

The effect of irrigation time and type of irrigation fluid on cartilage surface friction.

Science.gov (United States)

Stärke, F; Awiszus, F; Lohmann, C H; Stärke, C

2018-01-01

It is known that fluid irrigation used during arthroscopic procedures causes a wash-out of lubricating substances from the articular cartilage surface and leads to increased friction. It was the goal of this study to investigate whether this effect depends on the time of irrigation and type of fluid used. Rabbit hind legs were used for the tests. The knees were dissected and the friction coefficient of the femoral cartilage measured against glass in a boundary lubrication state. To determine the influence of irrigation time and fluid, groups of 12 knees received either no irrigation (control), 15, 60 or 120min of irrigation with lactated Ringer's solution or 60min of irrigation with normal saline or a sorbitol/mannitol solution. The time of irrigation had a significant effect on the static and kinetic coefficient of friction (CoF), as had the type of fluid. Longer irrigation time with Ringer's solution was associated with increased friction coefficients (relative increase of the kinetic CoF compared to the control after 15, 60 and 120min: 16%, 76% and 88% respectively). The sorbitol/mannitol solution affected the static and kinetic CoF significantly less than either Ringer's or normal saline. The washout of lubricating glycoproteins from the cartilage surface and the associated increase of friction can be effectively influenced by controlling the time of irrigation and type of fluid used. The time of exposure to the irrigation fluid should be as short as possible and monosaccharide solutions might offer a benefit compared to salt solutions in terms of the resultant friction. Copyright © 2017 Elsevier Ltd. All rights reserved.

Carbon and water footprints of irrigated corn and non-irrigated wheat in Northeast Spain.

Science.gov (United States)

Abrahão, Raphael; Carvalho, Monica; Causapé, Jesús

2017-02-01

Irrigation increases yields and allows several crops to be produced in regions where it would be naturally impossible due to limited rainfall. However, irrigation can cause several negative environmental impacts, and it is important to understand these in depth for the correct application of mitigation measures. The life cycle assessment methodology was applied herein to compare the main irrigated and non-irrigated crops in Northeast Spain (corn and wheat, respectively), identifying those processes with greater contribution to environmental impacts (carbon and water footprint categories) and providing scientifically-sound information to facilitate government decisions. Due to concerns about climate change and water availability, the methods selected for evaluation of environmental impacts were IPCC 2013 GWP (carbon footprint) and water scarcity indicator (water footprint). The area studied, a 7.38-km 2 basin, was monitored for 12 years, including the period before, during, and after the implementation of irrigation. The functional unit, to which all material and energy flows were associated with, was the cultivation of 1 ha, throughout 1 year. The overall carbon footprint for irrigated corn was higher, but when considering the higher productivity achieved with irrigation, the emissions per kilogram of corn decrease and finally favor this irrigated crop. When considering the water footprint, the volumes of irrigation water applied were so high that productivity could not compensate for the negative impacts associated with water use in the case of corn. Nevertheless, consideration of productivities and gross incomes brings the results closer. Fertilizer use (carbon footprint) and irrigation water (water footprint) were the main contributors to the negative impacts detected.

Making the user visible: analysing irrigation practices and farmers’ logic to explain actual drip irrigation performance

NARCIS (Netherlands)

Benouniche, M.; Kuper, M.; Hammani, A.; Boesveld, H.

2014-01-01

The actual performance of drip irrigation (irrigation efficiency, distribution uniformity) in the field is often quite different from that obtained in experimental stations. We developed an approach to explain the actual irrigation performance of drip irrigation systems by linking measured

The use of a rubble chimney for denitrification of irrigation return waters

Energy Technology Data Exchange (ETDEWEB)

Evans, Roy B; Kruger, Paul [Civil Engineering Department, Stanford University (United States)

1970-05-15

Biological denitrification has been proposed as a means of removing nitrates from waste waters to control eutrophication in receiving waters. A potential use for this method is the treatment of irrigation return waters containing high concentrations of nitrate-nitrogen, since direct discharge of such wastes may cause objectionable algal growth in the receiving waters. For example, the process may be used to treat agricultural waste waters in the San Joaquin Valley in California, where an estimated 580,000 acre-feet/year of return waters, containing 20 mg/l of nitrate-nitrogen, will require disposal by A.D. 2020. Two methods of biological denitrification are presently under study for possible use in the San Joaquin Valley. In one method nitrates are reduced to nitrogen gas by bacterial action in deep ponds; in the other method bacterial denitrification takes place in biological filters. In biological filters, bacteria are grown on columns of submerged stones. A possible alternative to the conventional construction of these filters is the creation of a rubble chimney by a contained nuclear explosion. This paper presents the results of a preliminary investigation of the feasibility of using a rubble chimney as a biological filter for denitrification. (author)

The use of a rubble chimney for denitrification of irrigation return waters

International Nuclear Information System (INIS)

Evans, Roy B.; Kruger, Paul

1970-01-01

Biological denitrification has been proposed as a means of removing nitrates from waste waters to control eutrophication in receiving waters. A potential use for this method is the treatment of irrigation return waters containing high concentrations of nitrate-nitrogen, since direct discharge of such wastes may cause objectionable algal growth in the receiving waters. For example, the process may be used to treat agricultural waste waters in the San Joaquin Valley in California, where an estimated 580,000 acre-feet/year of return waters, containing 20 mg/l of nitrate-nitrogen, will require disposal by A.D. 2020. Two methods of biological denitrification are presently under study for possible use in the San Joaquin Valley. In one method nitrates are reduced to nitrogen gas by bacterial action in deep ponds; in the other method bacterial denitrification takes place in biological filters. In biological filters, bacteria are grown on columns of submerged stones. A possible alternative to the conventional construction of these filters is the creation of a rubble chimney by a contained nuclear explosion. This paper presents the results of a preliminary investigation of the feasibility of using a rubble chimney as a biological filter for denitrification. (author)

How Patients Experience Antral Irrigation

Directory of Open Access Journals (Sweden)

Karin Blomgren

2015-01-01

Full Text Available Background Antral irrigation earlier had an important role in the diagnosis and treatment of rhinosinusitis. Nowadays, it is often considered too unpleasant. However, the experience of patients of this procedure has been very seldom evaluated. Nor has the effect on pain in rhinosinusitis been evaluated. The aim of this study was to evaluate patients’ experience of discomfort and pain during antral irrigation. We also assessed facial pain caused by rhinosinusitis before the procedure and pain soon after the procedure. Methods Doctors and 121 patients completed their questionnaires independently after antral irrigation in a university clinic, in a private hospital, and at a communal health center. Results Patients experienced mild pain during antral irrigation (mean and median visual analog scale score: <3. Their experience of pain during antral irrigation was closely comparable to pain during dental calculus scaling. Facial pain assessed before antral irrigation decreased quickly after the procedure. Conclusions Antral irrigation was well tolerated as an outpatient procedure. The procedure seems to relieve facial pain caused by the disease quickly. The role of antral irrigation in the treatment of acute rhinosinusitis will need further investigation.

Modernisation Strategy for National Irrigation Systems in the Philippines: Balanac and Sta. Maria River Irrigation Systems

NARCIS (Netherlands)

Delos Reyes, M.L.F.

2017-01-01

This book examines the nature and impact of irrigation system rehabilitation on increasing the actual area irrigated by the publicly funded canal irrigation systems of the Philippines. It proposes a system diagnosis approach for the development of a more appropriate and climate-smart irrigation

Monte Carlo codes and Monte Carlo simulator program

International Nuclear Information System (INIS)

Higuchi, Kenji; Asai, Kiyoshi; Suganuma, Masayuki.

1990-03-01

Four typical Monte Carlo codes KENO-IV, MORSE, MCNP and VIM have been vectorized on VP-100 at Computing Center, JAERI. The problems in vector processing of Monte Carlo codes on vector processors have become clear through the work. As the result, it is recognized that these are difficulties to obtain good performance in vector processing of Monte Carlo codes. A Monte Carlo computing machine, which processes the Monte Carlo codes with high performances is being developed at our Computing Center since 1987. The concept of Monte Carlo computing machine and its performance have been investigated and estimated by using a software simulator. In this report the problems in vectorization of Monte Carlo codes, Monte Carlo pipelines proposed to mitigate these difficulties and the results of the performance estimation of the Monte Carlo computing machine by the simulator are described. (author)

Year-Round Irrigation Schedule for a Tomato–Maize Rotation System in Reservoir-Based Irrigation Schemes in Ghana

Directory of Open Access Journals (Sweden)

Ephraim Sekyi-Annan

2018-05-01

Full Text Available Improving irrigation management in semi-arid regions of Sub-Saharan Africa is crucial to respond to increasing variability in rainfall and overcome deficits in current irrigation schemes. In small-scale and medium-scale reservoir-based irrigation schemes in the Upper East region of Ghana, we explored options for improving the traditional, dry season irrigation practices and assessed the potential for supplemental irrigation in the rainy season. The AquaCrop model was used to (i assess current water management in the typical tomato-maize rotational system; (ii develop an improved irrigation schedule for dry season cultivation of tomato; and (iii determine the requirement for supplemental irrigation of maize in the rainy season under different climate scenarios. The improved irrigation schedule for dry season tomato cultivation would result in a water saving of 130–1325 mm compared to traditional irrigation practices, accompanied by approximately a 4–14% increase in tomato yield. The supplemental irrigation of maize would require 107–126 mm of water in periods of low rainfall and frequent dry spells, and 88–105 mm in periods of high rainfall and rare dry spells. Therefore, year-round irrigated crop production may be feasible, using water saved during dry season tomato cultivation for supplemental irrigation of maize in the rainy season.

75 FR 38412 - Safety Zone; San Diego POPS Fireworks, San Diego, CA

Science.gov (United States)

2010-07-02

...-AA00 Safety Zone; San Diego POPS Fireworks, San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary... waters of San Diego Bay in support of the San Diego POPS Fireworks. This safety zone is necessary to... San Diego POPS Fireworks, which will include fireworks presentations conducted from a barge in San...

POBLACIÓN DE NEMATODOS EN FORRAJES TROPICALES EN DOS RANGOS DE ALTURA EN EL CANTÓN DE SAN CARLOS, ALAJUELA

Directory of Open Access Journals (Sweden)

Rodolfo WingChing-Jones

2011-01-01

Full Text Available Se caracterizó la población de nematodos fitoparásitos presente en los pastos Sorgo negro (Sorghum almus, Camerún (Pennisetum purpureum var Camerun, King grass (Pennisetum purpureum var King grass, Tanzania (Panicum maximum var Tanzania, Brizantha (Brachiaria brizantha, Toledo (Brachiaria brizantha var Toledo, Estrella africana (Cynodon nlemfuensis, Mombaza (Panicum maximum var Mombaza, Ratana (Ischaemum ciliare y la leguminosa maní forrajero (Arachis pintoi en la localidad de San Carlos, Alajuela, de junio a noviembre del 2003. Se tomaron 5 muestras compuestas de suelo y de las raíces contenidas en el volumen de suelo para los forrajes evaluados, excepto para el pasto King grass, el Ratana y el Maní forrajero, en donde el número de muestras compuestas fue de 10 para cada material. Los nematodos Pratylenchus sp., Helicotylenchus sp., Tylenchus sp., Criconemella sp., se identificaron en 8 de los pastos y en la leguminosa evaluada. El género Psilenchus sp., solo se presentó en el pasto Tanzania, mientras que el género Xiphinema sp., en los forrajes Tanzania, Brizantha, Ratana y en el maní forrajero. El género Paratylenchus sp., se contabilizó con los forrajes Tanzania, Brizantha y Ratana. En el pasto Toledo, Camerún y en el maní forrajero se observó Hemicycliophora sp. En cambio, Meloidogyne sp., se encontró en los pastos Brizantha y Ratana. Los nematodos no fitoparásitos se identificaron en los 9 pastos y la leguminosa evaluada.

Irrigation water sources and irrigation application methods used by U.S. plant nursery producers

Science.gov (United States)

Paudel, Krishna P.; Pandit, Mahesh; Hinson, Roger

2016-02-01

We examine irrigation water sources and irrigation methods used by U.S. nursery plant producers using nested multinomial fractional regression models. We use data collected from the National Nursery Survey (2009) to identify effects of different firm and sales characteristics on the fraction of water sources and irrigation methods used. We find that regions, sales of plants types, farm income, and farm age have significant roles in what water source is used. Given the fraction of alternative water sources used, results indicated that use of computer, annual sales, region, and the number of IPM practices adopted play an important role in the choice of irrigation method. Based on the findings from this study, government can provide subsidies to nursery producers in water deficit regions to adopt drip irrigation method or use recycled water or combination of both. Additionally, encouraging farmers to adopt IPM may enhance the use of drip irrigation and recycled water in nursery plant production.

Wireless sensor networks for irrigation management

Science.gov (United States)

Sustaining an adequate food supply for the world's population will require advancements in irrigation technology and improved irrigation management. Site-specific irrigation and automatic irrigation scheduling are examples of strategies to deal with declining arable land and limited fresh water reso...

PREFACE: Polycrystal Modelling with Experimental Integration: A Symposium Honoring Carlos Tomé (San Diego, CA, USA, February 27-March 3 2011) Polycrystal Modelling with Experimental Integration: A Symposium Honoring Carlos Tomé (San Diego, CA, USA, February 27-March 3 2011)

Science.gov (United States)

Lebensohn, Ricardo A.

2012-03-01

This special issue contains selected contributions from invited speakers to the 'Polycrystal Modelling with Experimental Integration: A Symposium Honoring Carlos Tomé', held as part of the 2011 TMS Annual Meeting and Exhibition, that took place on February 27-March 3, 2011 in San Diego, CA, USA. This symposium honored the remarkable contributions of Dr Carlos N Tomé to the field of mechanical behavior of polycrystalline materials, on the occasion of his 60th birthday. Throughout his career, Dr Tomé has pioneered the theoretical and numerical development of models of polycrystal mechanical behavior, with emphasis on the role played by texture and microstructure on the anisotropic behavior of engineering materials. His many contributions have been critical in establishing a strong connection between models and experiments, and in bridging different scales in the pursuit of robust multiscale models with experimental integration. Among his achievements, the numerical codes that Dr Tomé and co-workers have developed are extensively used in the materials science and engineering community as predictive tools for parameter identification, interpretation of experiments, and multiscale calculations in academia, national laboratories and industry. The symposium brought together materials scientists and engineers to address current theoretical, computational and experimental issues related to microstructure-property relationships in polycrystalline materials deforming in different regimes, including the effects of single crystal anisotropy, texture and microstructure evolution. Synergetic studies, involving different crystal plasticity-based models, including multiscale implementations of the latter, and measurements of global and local textures, internal strains, dislocation structures, twinning, phase distribution, etc, were discussed in more than 90 presentations. The papers in this issue are representative of the different length-scales, materials, and experimental and

Scintigraphic assessment of colostomy irrigation.

Science.gov (United States)

Christensen, P.; Olsen, N.; Krogh, K.; Laurberg, S.

2002-09-01

OBJECTIVE: This study aims to evaluate colonic transport following colostomy irrigation with a new scintigraphic technique. MATERIALS AND METHODS: To label the bowel contents 19 patients (11 uncomplicated colostomy irrigation, 8 complicated colostomy irrigation) took 111In-labelled polystyrene pellets one and two days before investigation. 99mTc-DTPA was mixed with the irrigation fluid to assess its extent within the bowel. Scintigraphy was performed before and after a standardized washout procedure. The colon was divided into three segments 1: the caecum andascending colon; 2: the transverse colon; 3: the descending and sigmoid colon. Assuming ordered evacuation of the colon, the contribution of each colonic segment to the total evacuation was expressed as a percentage of the original segmental counts. These were added to reach a total defaecation score (range: 0-300). RESULTS: In uncomplicated colostomy irrigation, the median defaecation score was 235 (range: 145-289) corresponding to complete evacuation of the descending and transverse colon and 35% evacuation of the caecum/ascending colon. In complicated colostomy irrigation it was possible to distinguish specific emptying patterns. The retained irrigation fluid reached the caecum in all but one patient. CONCLUSION: Scintigraphy can be used to evaluate colonic emptying following colostomy irrigation.

Modeling irrigation behavior in groundwater systems

Science.gov (United States)

Foster, Timothy; Brozović, Nicholas; Butler, Adrian P.

2014-08-01

Integrated hydro-economic models have been widely applied to water management problems in regions of intensive groundwater-fed irrigation. However, policy interpretations may be limited as most existing models do not explicitly consider two important aspects of observed irrigation decision making, namely the limits on instantaneous irrigation rates imposed by well yield and the intraseasonal structure of irrigation planning. We develop a new modeling approach for determining irrigation demand that is based on observed farmer behavior and captures the impacts on production and water use of both well yield and climate. Through a case study of irrigated corn production in the Texas High Plains region of the United States we predict optimal irrigation strategies under variable levels of groundwater supply, and assess the limits of existing models for predicting land and groundwater use decisions by farmers. Our results show that irrigation behavior exhibits complex nonlinear responses to changes in groundwater availability. Declining well yields induce large reductions in the optimal size of irrigated area and irrigation use as constraints on instantaneous application rates limit the ability to maintain sufficient soil moisture to avoid negative impacts on crop yield. We demonstrate that this important behavioral response to limited groundwater availability is not captured by existing modeling approaches, which therefore may be unreliable predictors of irrigation demand, agricultural profitability, and resilience to climate change and aquifer depletion.

Assessment of Irrigation Water Quality and Suitability for Irrigation in ...

African Journals Online (AJOL)

A number of factors like geology, soil, effluents, sewage disposal and other environmental conditions in which the water stays or moves and interacts are among the factors that affect the quality of irrigation water. This study was conducted to determine the quality and suitability of different water sources for irrigation purpose ...

Effect of irrigation on heavy metals content of wastewater irrigated ...

African Journals Online (AJOL)

There is an urgent need to educate farmers on the dangers of the presence of heavy metals in soils as well as the quality of irrigation water especially if it comes from tanning industries for increased crop production. Accordingly, soil and irrigation wastewater study was conducted to assess the concentrations of heavy ...

An assessment of colostomy irrigation.

Science.gov (United States)

Laucks, S S; Mazier, W P; Milsom, J W; Buffin, S E; Anderson, J M; Warwick, M K; Surrell, J A

1988-04-01

One hundred patients with permanent sigmoid colostomies were surveyed to determine their satisfaction and success with the "irrigation" technique of colostomy management. Most patients who irrigate their colostomies achieve continence. Odors and skin irritation are minimized. The irrigation method is economical, time efficient, and allows a reasonably liberal diet. It avoids bulky appliances and is safe. In appropriately selected patients, the irrigation technique is the method of choice for management of an end-sigmoid colostomy.

Irrigation and Autocracy

DEFF Research Database (Denmark)

Bentzen, Jeanet Sinding; Kaarsen, Nicolai; Wingender, Asger Moll

2017-01-01

. We argue that the effect has historical origins: irrigation allowed landed elites in arid areas to monopolize water and arable land. This made elites more powerful and better able to oppose democratization. Consistent with this conjecture, we show that irrigation dependence predicts land inequality...

STUDY ON MICROBIAL COMMUNITIES AND SOIL ORGANIC MATTER IN IRRIGATED AND NON-IRRIGATED VERTISOL FROM BOIANU

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Sorina Dumitru

2012-12-01

Full Text Available Irrigation, when administered correctly, confers the producers the possibility to overcome drought effects and obtain higher yields, supplementing the quality of food for animals or human consumers. In the mean time, soil erosion, pathogens attack and nutrients or pesticides spreading can be prevented by an adequate management of irrigation water. As a consequence, soil microbial community structure, composition and activities, as well as the organic matter quality can be different from those in non-irrigated soil. Research have been carried out in order to assess changes in bacterial and fungal communities and activity in irrigated Vertisol from Boianu, as compared with non-irrigated. The paper presents the results concerning the taxonomical composition of bacterial and fungalmicroflora in the horizons of the two soil profiles, as well as the level of CO2 released by microorganisms. Chromatographic aspects of humus fractions were used to characterize the organic matter in irrigated and nonirrigated soil. Increased moisture and lowered temperature in Ap horizon of irrigated soil increased bacterial counts(18 x106 viable cells x g-1 dry soil and their metabolic activity expressed by carbon dioxide released (46.838mg CO2 x g-1 dry soil comparatively with non- irrigated soil. Fungal microflora was more abundant after 25-50cm under irrigation. Species diversity slightly increased under irrigation in both upper and lower part of soil profile. In irrigated soil, associations of species belonging to bacterial genera Pseudomonas and Bacillus were dominant in surface and white actinomycetes in the depth. Fungal consortia of Penicillium, Aspergillus and Fusarium dominated in both soil profiles.Irrigation induced changes in the quantity and quality of soil organic matter, as well as in the aspect of their migration pattern, as revealed on circular chromatograms.

Are There Infinite Irrigation Trees?

Science.gov (United States)

Bernot, M.; Caselles, V.; Morel, J. M.

2006-08-01

In many natural or artificial flow systems, a fluid flow network succeeds in irrigating every point of a volume from a source. Examples are the blood vessels, the bronchial tree and many irrigation and draining systems. Such systems have raised recently a lot of interest and some attempts have been made to formalize their description, as a finite tree of tubes, and their scaling laws [25], [26]. In contrast, several mathematical models [5], [22], [10], propose an idealization of these irrigation trees, where a countable set of tubes irrigates any point of a volume with positive Lebesgue measure. There is no geometric obstruction to this infinitesimal model and general existence and structure theorems have been proved. As we show, there may instead be an energetic obstruction. Under Poiseuille law R(s) = s -2 for the resistance of tubes with section s, the dissipated power of a volume irrigating tree cannot be finite. In other terms, infinite irrigation trees seem to be impossible from the fluid mechanics viewpoint. This also implies that the usual principle analysis performed for the biological models needs not to impose a minimal size for the tubes of an irrigating tree; the existence of the minimal size can be proven from the only two obvious conditions for such irrigation trees, namely the Kirchhoff and Poiseuille laws.

Local land-atmosphere feedbacks limit irrigation demand

Science.gov (United States)

Decker, Mark; Ma, Shaoxiu; Pitman, Andy

2017-05-01

Irrigation is known to influence regional climate but most studies forecast and simulate irrigation with offline (i.e. land only) models. Using south eastern Australia as a test bed, we demonstrate that irrigation demand is fundamentally different between land only and land-atmosphere simulations. While irrigation only has a small impact on maximum temperature, the semi-arid environment experiences near surface moistening in coupled simulations over the irrigated regions, a feedback that is prevented in offline simulations. In land only simulations that neglect the local feedbacks, the simulated irrigation demand is 25% higher and the standard deviation of the mean irrigation rate is 60% smaller. These local-scale irrigation-driven feedbacks are not resolved in coarse-resolution climate models implying that use of these tools will overestimate irrigation demand. Future studies of irrigation demand must therefore account for the local land-atmosphere interactions by using coupled frameworks, at a spatial resolution that captures the key feedbacks.

Carlos Alberto Seguín: paradigma docente de la Facultad de Medicina de San Fernando, a 100 años de su nacimiento

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Alberto Perales

2008-03-01

Full Text Available A propósito del primer centenario del nacimiento (1907-2007, de Carlos Alberto Seguín, describimos tres facetas de su ejemplar trayectoria: sus años formativos, su presencia en la Facultad de Medicina de San Fernando, en el difícil periodo de los 60, y su digna actitud ante la muerte. Las avanzadas ideas sobre la nueva formación médica que Seguín postulaba, insistiendo en la necesidad de estudiar, diagnosticar y tratar tanto el área psicológica cuanto física del ser humano y no solo ‘su enfermedad’. Además, su propuesta metodológica de los ‘grupos formativos’, para que los estudiantes tuvieran la oportunidad de elaborar sus vivencias de contacto con el enfermo, no fueron bien comprendidas en la época que las formulara, creándose conflictos que el profesor prefirió evitar por el bien de la institución y porque comprendió que el estudiante de esa época no estaba dispuesto a realizar el esfuerzo necesario para tal logro. Su digna actitud ante la muerte se grafica en un verso que escribiera poco antes de morir. Seguín falleció el sábado 26 de agosto de 1995. Debe ser recordado como un paradigma docente sanmarquino.

Monte Carlo and Quasi-Monte Carlo Sampling

CERN Document Server

Lemieux, Christiane

2009-01-01

Presents essential tools for using quasi-Monte Carlo sampling in practice. This book focuses on issues related to Monte Carlo methods - uniform and non-uniform random number generation, variance reduction techniques. It covers several aspects of quasi-Monte Carlo methods.

Irrigation of steppe soils in the south of Russia: Problems and solutions (Analysis of Irrigation Practices in 1950-1990)

Science.gov (United States)

Minashina, N. G.

2009-07-01

Experience in irrigation of chernozems in the steppe zone of Russia for a period from 1950 to 1990 is analyzed. By the end of this period and in the subsequent years, the areas under irrigation reduced considerably, and the soil productivity worsened. This was caused by the improper design of irrigation systems, on the one hand, and by the low tolerance of chernozems toward increased moistening upon irrigation, on the other hand. The analysis of the factors and regimes of soil formation under irrigation conditions shows that irrigation-induced changes in the soil hydrology also lead to changes in the soil physicochemical, biochemical, and other properties. In particular, changes in the composition of exchangeable cations lead to the development of solonetzic process. In many areas, irrigation of chernozems was accompanied by the appearance of solonetzic, vertic, saline, and eroded soils. The development of soil degradation processes is described. In general, the deterioration of irrigated chernozems was related to the absence of adequate experience in irrigation of steppe soils, unskilled personnel, improper regime of irrigation, and excessively high rates of watering. In some cases, the poor quality of irrigation water resulted in the development of soil salinization and alkalization. To improve the situation, the training of personnel is necessary; the strategy of continuous irrigation should be replaced by the strategy of supplementary irrigation in the critical periods of crop development.

Irrigation management of sigmoid colostomy.

Science.gov (United States)

Jao, S W; Beart, R W; Wendorf, L J; Ilstrup, D M

1985-08-01

Questionnaires were sent to 270 patients who had undergone abdominoperineal resection and sigmoid colostomy at the Mayo Clinic, Rochester, Minn, during the ten years from 1972 to 1982; 223 patients returned their questionnaires with evaluable data. Sixty percent of the patients were continent with irrigation, and 22% were incontinent with irrigation. Eighteen percent had discontinued irrigation for various reasons. The proportion continent was higher in women, younger patients, and previously constipated patients. A poorly constructed colostomy may cause acute angle, parastoma hernia, stomal prolapse, or stenosis and thus be the cause of failure of irrigation.

Assessing the changes of groundwater recharge / irrigation water use between SRI and traditional irrigation schemes in Central Taiwan

Science.gov (United States)

Chen, Shih-Kai; Jang, Cheng-Shin; Tsai, Cheng-Bin

2015-04-01

To respond to agricultural water shortage impacted by climate change without affecting rice yield in the future, the application of water-saving irrigation, such as SRI methodology, is considered to be adopted in rice-cultivation in Taiwan. However, the flooded paddy fields could be considered as an important source of groundwater recharge in Central Taiwan. The water-saving benefit of this new methodology and its impact on the reducing of groundwater recharge should be integrally assessed in this area. The objective of this study was to evaluate the changes of groundwater recharge/ irrigation water use between the SRI and traditional irrigation schemes (continuous irrigation, rotational irrigation). An experimental paddy field located in the proximal area of the Choushui River alluvial fan (the largest groundwater pumping region in Taiwan) was chosen as the study area. The 3-D finite element groundwater model (FEMWATER) with the variable boundary condition analog functions, was applied in simulating groundwater recharge process and amount under traditional irrigation schemes and SRI methodology. The use of effective rainfall was taken into account or not in different simulation scenarios for each irrigation scheme. The simulation results showed that there were no significant variations of infiltration rate in the use of effective rainfall or not, but the low soil moisture setting in deep soil layers resulted in higher infiltration rate. Taking the use of effective rainfall into account, the average infiltration rate for continuous irrigation, rotational irrigation, and SRI methodology in the first crop season of 2013 were 4.04 mm/day, 4.00 mm/day and 3.92 mm/day, respectively. The groundwater recharge amount of SRI methodology was slightly lower than those of traditional irrigation schemes, reducing 4% and 2% compared with continuous irrigation and rotational irrigation, respectively. The field irrigation requirement amount of SRI methodology was significantly

Irrigation water management: Basic principles and applications

OpenAIRE

Ella, Victor B.

2007-01-01

This presentation defines the term, irrigation, as well as explains the common methods of irrigation in attempt to define the fundamental principles needed to wisely design an irrigation system. It outlines a typical drip irrigation set-up, and discusses management of an irrigation system, including water volume application suggestions. LTRA-5 (Agroforestry and Sustainable Vegetable Production)

Irrigation-based livelihood challenges and opportunities : a gendered technology of irrigation development intervention in the Lower Moshi irrigation scheme Tanzania

NARCIS (Netherlands)

Kissawike, K.

2008-01-01

This thesis is a study of a modernised irrigation scheme in Tanzania. It aims to
understand how irrigation and agricultural technologies have interacted with local
society to transform production, paying particular attention to gender relations and
changes for women farmers. The

Comparative study of irrigation water use and groundwater recharge under various irrigation schemes in an agricultural region, central Taiwan

Science.gov (United States)

Chen, Shih-Kai; Jang, Cheng-Shin; Tsai, Cheng-Bin

2016-04-01

The risk of rice production has increased notably due to climate change in Taiwan. To respond to growing agricultural water shortage without affecting normal food production in the future, the application of water-saving irrigation will be a substantial resolution. However, the adoption of water-saving irrigation may result in the reducing of groundwater recharge because continuous flooding in the paddy fields could be regarded as an important source for groundwater recharge. The aim of this study was to evaluate the irrigation water-saving benefit and groundwater recharge deficit when adopting the System of Rice Intensification, known as SRI methodology, in the Choushui River alluvial fan (the largest groundwater pumping and the most important rice-cropping region in central Taiwan). The three-dimensional finite element groundwater model, FEMWATER, was applied to simulate the infiltration process and groundwater recharge under SRI methodology and traditional irrigation schemes including continuous irrigation, and rotational irrigation in two rice-crop periods with hydro-climatic data of 2013. The irrigation water use was then calculated by water balance. The results showed that groundwater recharge amount of SRI methodology was slightly lower than those of traditional irrigation schemes, reduced 3.6% and 1.6% in the first crop period, and reduced 3.2% and 1.6% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. However, the SRI methodology achieved notably water-saving benefit compared to the disadvantage of reducing the groundwater recharge amount. The field irrigation requirement amount of SRI methodology was significantly lower than those of traditional irrigation schemes, saving 37% and 20% of irrigation water in the first crop period, and saving 53% and 35% in the second crop period, compared with continuous irrigation and rotational irrigation, respectively. Therefore, the amount of groundwater pumping for

Where Does the Irrigation Water Go? An Estimate of the Contribution of Irrigation to Precipitation Using MERRA

Science.gov (United States)

Wei, Jiangfeng; Dirmeyer, Paul A.; Wisser, Dominik; Bosilovich, Michael G.; Mocko, David M.

2013-01-01

Irrigation is an important human activity that may impact local and regional climate, but current climate model simulations and data assimilation systems generally do not explicitly include it. The European Centre for Medium-Range Weather Forecasts (ECMWF) Interim Re-Analysis (ERA-Interim) shows more irrigation signal in surface evapotranspiration (ET) than the Modern-Era Retrospective Analysis for Research and Applications (MERRA) because ERA-Interim adjusts soil moisture according to the observed surface temperature and humidity while MERRA has no explicit consideration of irrigation at the surface. But, when compared with the results from a hydrological model with detailed considerations of agriculture, the ET from both reanalyses show large deficiencies in capturing the impact of irrigation. Here, a back-trajectory method is used to estimate the contribution of irrigation to precipitation over local and surrounding regions, using MERRA with observation-based corrections and added irrigation-caused ET increase from the hydrological model. Results show substantial contributions of irrigation to precipitation over heavily irrigated regions in Asia, but the precipitation increase is much less than the ET increase over most areas, indicating that irrigation could lead to water deficits over these regions. For the same increase in ET, precipitation increases are larger over wetter areas where convection is more easily triggered, but the percentage increase in precipitation is similar for different areas. There are substantial regional differences in the patterns of irrigation impact, but, for all the studied regions, the highest percentage contribution to precipitation is over local land.

Effective colostomy irrigation.

Science.gov (United States)

Mazier, W P; Dignan, R D; Capehart, R J; Smith, B G

1976-06-01

The ultimate goal of the cone method of colostomy irrigation is to return patients with colostomies to their former role in society with confidence in themselves to the extent that having a colostomy is not considered a handicap. The results have generally been excellent. We believe all patients with stomas should be afforded the opportunity to attempt colostomy irrigation.

Potato yield and yield structure depending on irrigation

Directory of Open Access Journals (Sweden)

Milić Stanko

2010-01-01

Full Text Available In the agroclimatic conditions of the Vojvodina Province, the application of an economic water regime and modern technology is necessary for stable and intensive potato production. A two-year experiment on calcareous chernozem was carried out to determine how irrigation and different pre-irrigation soil moisture affect potato yield and distribution of tuber fraction in the potato yield. The block-design trial had four replicates and was adapted for sprinkler irrigation conditions. It included four treatments: irrigation with pre-irrigation moisture levels of 60 % of field water capacity (FC, irrigation with pre-irrigation moisture levels of 70 % (FC, irrigation with pre-irrigation moisture levels of 80% (FC, and a non-irrigated control treatment. Irrigation significantly increased the yield of potato, which increased from 37.27 % to 75.86 %. Under irrigation, the percentage of small fractions decreased in favour of the 55 mm one, or fractions above the 45-55 mm range. On average, irrigated treatments produced significantly more tubers than the conditions of natural water supply. .

Modelamiento del flujo y transporte de metales pesado en acuífero superior de la zona urbana de la parroquia de San Carlos provincia de Orellana a través de la caracterización In Situ del subsuelo y de las aguas subterráneas someras

OpenAIRE

Bonifaz García, Hugo Fabián

2015-01-01

Se sabe que algunos acuíferos Oriente Ecuatoriano están contaminados con metales pesados provenientes de los hidrocarburos de la industria petrolera, por lo que en las zonas rurales cercanas a los campos explotación de petróleo, los colonos beben agua subterránea contaminada. La parroquia de San Carlos, provincia de Orellana, ha sido objeto de varios estudios relacionados con la contaminación por petróleo y las enfermedades asociadas. No obstante, ninguno de los estudios incluyó el análisis d...

78 FR 19103 - Safety Zone; Spanish Navy School Ship San Sebastian El Cano Escort; Bahia de San Juan; San Juan, PR

Science.gov (United States)

2013-03-29

...-AA00 Safety Zone; Spanish Navy School Ship San Sebastian El Cano Escort; Bahia de San Juan; San Juan... temporary moving safety zone on the waters of Bahia de San Juan during the transit of the Spanish Navy... Channel entrance, and to protect the high ranking officials on board the Spanish Navy School Ship San...

Sustainability of coastal resource use in San Quintin, Mexico.

Science.gov (United States)

Aguirre-Muñoz, A; Buddemeier, R W; Camacho-Ibar, V; Carriquiry, J D; Ibarra-Obando, S E; Massey, B W; Smith, S V; Wulff, F

2001-05-01

San Quintin, Mexico, provides a useful site for integrated analyses of material fluxes and socioeconomic constraints in a geographically isolated system. Natural resource utilization on the land is dominated by groundwater exploitation for cultivation of horticulture crops (primarily tomatoes). Irrigation exceeds water recharge minus export by a factor of 6. Resource utilization in the bay is dominated by oyster culture; food for the oysters is provided by tidal exchange of bay and ocean water. Consideration of oyster respiration and system respiration suggests that the present level of aquaculture is about 40% of the sustainable level. A "physical unsustainability index" (PhUI) was developed to measure the proportional departure of utilization of the most limiting resource for sustainability: 6 on land; 0.4 in the bay. Based on PhUI and measures of economic development, we conclude that aquaculture is more viable than agriculture.

Performing drip irrigation by the farmer managed Seguia Khrichfa irrigation system, Morocco

NARCIS (Netherlands)

Kooij, van der S.

2016-01-01

Drip irrigation is represented in literature and agricultural policies as a modern and water saving technology. Because this technology is often associated with ‘modern’ agriculture and development, it seems out-of-place in ‘traditional’ farmer managed irrigation systems (FMIS). Thinking along

Scheduling of Irrigation and Leaching Requirements

Directory of Open Access Journals (Sweden)

Amer Hassan Al-haddad

2015-03-01

Full Text Available Iraq depends mainly on Tigris and Euphrates Rivers to provide high percentage of agricultural water use for thousands years. At last years, Iraq is suffering from shortage in water resources due to global climate changes and unfair water politics of the neighboring countries, which affected the future of agriculture plans for irrigation, added to that the lack of developed systems of water management in the irrigation projects and improper allocation of irrigation water, which reduces water use efficiency and lead to losing irrigation water and decreasing in agricultural yield. This study aims at studying the usability of irrigation and leaching scheduling within the irrigating projects and putting a complete annual or seasonal irrigation program as a solution for the scarcity of irrigation water, the increase of irrigation efficiency, lessening the salinity in the projects and preparing an integral irrigation calendar through field measurements of soil physical properties and chemical for project selected and compared to the results of the irrigation scheduling and leaching with what is proposed by the designers. The process is accomplished by using a computer program which was designed by Water Resources Department at the University of Baghdad, with some modification to generalize it and made it applicable to various climatic zone and different soil types. Study area represented by large project located at the Tigris River, and this project was (Al-Amara irrigation project. Sufficient samples of project's soil were collected so as to identify soil physical and chemical properties and the salinity of soil and water as well as identifying the agrarian cycles virtually applied to this project. Finally, a comparison was conducted between the calculated water quantities and the suggested ones by the designers. The research results showed that using this kind of scheduling (previously prepared irrigation and leaching scheduling with its properties

Compact High Resolution SANS using very cold neutrons (VCN-SANS)

International Nuclear Information System (INIS)

Kennedy, S.; Yamada, M.; Iwashita, Y.; Geltenbort, P.; Bleuel, M.; Shimizu, H.

2011-01-01

SANS (Small Angle Neutron Scattering) is a popular method for elucidation of nano-scale structures. However science continually challenges SANS for higher performance, prompting exploration of ever-more exotic and expensive technologies. We propose a compact high resolution SANS, using very cold neutrons, magnetic focusing lens and a wide-angle spherical detector. This system will compete with modern 40 m pinhole SANS in one tenth of the length, matching minimum Q, Q-resolution and dynamic range. It will also probe dynamics using the MIEZE method. Our prototype lens (a rotating permanent-magnet sextupole), focuses a pulsed neutron beam over 3-5 nm wavelength and has measured SANS from micelles and polymer blends. (authors)

Biological degradation of chernozems under irrigation

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Oksana Naydyonova

2014-12-01

Full Text Available We studied the changes in the state of microbial cenosis of Ukraine’s chernozems under irrigation. Considerable part of Ukraine’s chernozems is located in the areas where humidification is insufficient and unstable. Irrigation is a soil-reclamation measure for chernozems of Ukrainian Forest-steppe and Steppe which enables getting the assured yield, especially vegetable and fodder crops. At the same time, irrigation is a powerful anthropogenic factor that affects the soil, causes a significant transformation of many of its properties and regimes including biological ones. Often these changes are negative. The purpose of our investigation was to identify changes in the state of microbial cenoses of chernozem soils under irrigation which depend on such factors as the quality of irrigation water, the duration and intensity of irrigation, the initial properties of soil, the structure of crop rotation, usage of fertilizing systems and agroameliorative techniques. We identified direction and evaluated a degree of changes in biological properties of chernozems under influence of irrigation in different agro-irrigational and soil-climatic conditions. In the long-term stationary field experiments we identified the following biological indices of irrigated soils and their non-irrigated analogues: a number of microorganisms which belong to main ecological-trophic groups, activity of soil enzymes (dehydrogenase, invertase, phenol oxidase, soil phytotoxic activity, cellulose destroying capacity of soil, indices of oligotrophy and mineralization, summary biological index (SBI and index of biological degradation (BDI. Results of researches showed that irrigation unbalanced the soil ecosystem and stipulated the forming of microbial cenosis with new parameters. Long-term intensive irrigation of typical chernozem (Kharkiv Region with fresh water under condition of 4-fields vegetable crop rotation led to the degradation changes of its microbial cenosis such as

Irrigation Analysis Based on Long-Term Weather Data

Directory of Open Access Journals (Sweden)

James R. Mahan

2016-08-01

Full Text Available Irrigation management is based upon delivery of water to a crop in the correct amount and time, and the crop’s water need is determined by calculating evapotranspiration (ET using weather data. In 1994, an ET-network was established in the Texas High Plains to manage irrigation on a regional scale. Though producers used the ET-network, by 2010 public access was discontinued. Why did producers allow a valuable irrigation-management tool to be eliminated? Our objective was to analyze the effect of declining well capacities on the usefulness of cotton ET (ETc for irrigation. Thirty years (1975–2004 of daily ETc data were used to compare irrigation demand vs. irrigation responses at four locations, analyzed for multiple years and range of well capacities for three irrigation-intervals. Results indicated that when well capacities declined to the point that over-irrigation was not possible, the lower well capacities reduced the value of ETc in terms of the number of irrigations and total amount of water applied. At well capacities <1514 L·min−1 the fraction of irrigations for which ETc information was used to determine the irrigation amount was <35% across years and irrigation intervals. The value of an ETc-based irrigation may fall into disuse when irrigation-water supplies decline.

Evaluation of hydraulic performance of downstream-controlled Maira-PHLC irrigation canals under crop-based irrigation operations

NARCIS (Netherlands)

Munir, S.; Schultz, B.; Suryadi, F.X.; Bharati, L.

2012-01-01

Demand-based irrigation systems are operated according to crop water requirements. As crop water requirements remain variable throughout the growing season, the discharges in the canal also vary to meet demands. The irrigation system under study is a demand-based semi-automatic irrigation system,

Role of sediment in the design and management of irrigation canals : Sunsari Morang Irrigation Scheme, Nepal

NARCIS (Netherlands)

Paudel, K.

2010-01-01

Sediment transport in irrigation canals The sediment transport aspect is a major factor in irrigation development as it determines to a large extent the sustainability of an irrigation scheme, particularly in case of unlined canals in alluvial soils. Investigations in this respect started since

Newer Root Canal Irrigants in Horizon: A Review

Directory of Open Access Journals (Sweden)

Sushma Jaju

2011-01-01

Full Text Available Sodium hypochloride is the most commonly used endodontic irrigant, despite limitations. None of the presently available root canal irrigants satisfy the requirements of ideal root canal irrigant. Newer root canal irrigants are studied for potential replacement of sodium hypochloride. This article reviews the potential irrigants with their advantages and limitations with their future in endodontic irrigation.

Irrigation Water Management in Latin America

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Aureo S de Oliveira

2009-12-01

Full Text Available Latin American countries show a great potential for expanding their irrigated areas. Irrigation is important for strengthening local and regional economy and for enhancing food security. The present paper aimed at providing a brief review on key aspects of irrigation management in Latin America. Poor irrigation management can have great impact on crop production and on environment while good management reduces the waste of soil and water and help farmers maximizing their profits. It was found that additional research is needed to allow a better understanding of crop water requirements under Latin American conditions as well as to provide farmers with local derived information for irrigation scheduling. The advantages of deficit irrigation practices and the present and future opportunities with the application of remote sensing tools for water management were also considered. It is clear that due to the importance of irrigated agriculture, collaborative work among Latin American researchers and institutions is of paramount importance to face the challenges imposed by a growing population, environment degradation, and competition in the global market.

[Irrigants and intracanal medicaments in endodontics].

Science.gov (United States)

Zehnder, Matthias; Lehnert, Birgit; Schönenberger, Kathrin; Waltimo, Tuomas

2003-01-01

Modern, biologic root canal therapy should be performed with suitable irrigating solutions and intracanal medicaments. The goal of endodontic treatment is to free the treated tooth from infection and prevent reinfection as thoroughly as possible by means which do not put the organism at risk. In this review of the literature, an evidence-based concept for irrigation and medication of root canal systems is presented. Irrigants and medicaments are discussed with respect to their antimicrobial, tissue-dissolving and endotoxin-decontaminating capacity in relation to their systemic toxicity. Recent findings pertaining to interactions of root canal medicaments and irrigating solutions and their impact on a sound irrigating and medicating concept are discussed.

Irrigation in dose assessments models

Energy Technology Data Exchange (ETDEWEB)

Bergstroem, Ulla; Barkefors, Catarina [Studsvik RadWaste AB, Nykoeping (Sweden)

2004-05-01

SKB has carried out several safety analyses for repositories for radioactive waste, one of which was SR 97, a multi-site study concerned with a future deep bedrock repository for high-level waste. In case of future releases due to unforeseen failure of the protective multiple barrier system, radionuclides may be transported with groundwater and may reach the biosphere. Assessments of doses have to be carried out with a long-term perspective. Specific models are therefore employed to estimate consequences to man. It has been determined that the main pathway for nuclides from groundwater or surface water to soil is via irrigation. Irrigation may cause contamination of crops directly by e.g. interception or rain-splash, and indirectly via root-uptake from contaminated soil. The exposed people are in many safety assessments assumed to be self-sufficient, i.e. their food is produced locally where the concentration of radionuclides may be the highest. Irrigation therefore plays an important role when estimating consequences. The present study is therefore concerned with a more extensive analysis of the role of irrigation for possible future doses to people living in the area surrounding a repository. Current irrigation practices in Sweden are summarised, showing that vegetables and potatoes are the most common crops for irrigation. In general, however, irrigation is not so common in Sweden. The irrigation model used in the latest assessments is described. A sensitivity analysis is performed showing that, as expected, interception of irrigation water and retention on vegetation surfaces are important parameters. The parameters used to describe this are discussed. A summary is also given how irrigation is proposed to be handled in the international BIOMASS (BIOsphere Modelling and ASSessment) project and in models like TAME and BIOTRAC. Similarities and differences are pointed out. Some numerical results are presented showing that surface contamination in general gives the

Irrigation in dose assessments models

International Nuclear Information System (INIS)

Bergstroem, Ulla; Barkefors, Catarina

2004-05-01

SKB has carried out several safety analyses for repositories for radioactive waste, one of which was SR 97, a multi-site study concerned with a future deep bedrock repository for high-level waste. In case of future releases due to unforeseen failure of the protective multiple barrier system, radionuclides may be transported with groundwater and may reach the biosphere. Assessments of doses have to be carried out with a long-term perspective. Specific models are therefore employed to estimate consequences to man. It has been determined that the main pathway for nuclides from groundwater or surface water to soil is via irrigation. Irrigation may cause contamination of crops directly by e.g. interception or rain-splash, and indirectly via root-uptake from contaminated soil. The exposed people are in many safety assessments assumed to be self-sufficient, i.e. their food is produced locally where the concentration of radionuclides may be the highest. Irrigation therefore plays an important role when estimating consequences. The present study is therefore concerned with a more extensive analysis of the role of irrigation for possible future doses to people living in the area surrounding a repository. Current irrigation practices in Sweden are summarised, showing that vegetables and potatoes are the most common crops for irrigation. In general, however, irrigation is not so common in Sweden. The irrigation model used in the latest assessments is described. A sensitivity analysis is performed showing that, as expected, interception of irrigation water and retention on vegetation surfaces are important parameters. The parameters used to describe this are discussed. A summary is also given how irrigation is proposed to be handled in the international BIOMASS (BIOsphere Modelling and ASSessment) project and in models like TAME and BIOTRAC. Similarities and differences are pointed out. Some numerical results are presented showing that surface contamination in general gives the

Sediment Transport Model for a Surface Irrigation System

Directory of Open Access Journals (Sweden)

Damodhara R. Mailapalli

2013-01-01

Full Text Available Controlling irrigation-induced soil erosion is one of the important issues of irrigation management and surface water impairment. Irrigation models are useful in managing the irrigation and the associated ill effects on agricultural environment. In this paper, a physically based surface irrigation model was developed to predict sediment transport in irrigated furrows by integrating an irrigation hydraulic model with a quasi-steady state sediment transport model to predict sediment load in furrow irrigation. The irrigation hydraulic model simulates flow in a furrow irrigation system using the analytically solved zero-inertial overland flow equations and 1D-Green-Ampt, 2D-Fok, and Kostiakov-Lewis infiltration equations. Performance of the sediment transport model was evaluated for bare and cropped furrow fields. The results indicated that the sediment transport model can predict the initial sediment rate adequately, but the simulated sediment rate was less accurate for the later part of the irrigation event. Sensitivity analysis of the parameters of the sediment module showed that the soil erodibility coefficient was the most influential parameter for determining sediment load in furrow irrigation. The developed modeling tool can be used as a water management tool for mitigating sediment loss from the surface irrigated fields.

Bayesian Belief Networks Approach for Modeling Irrigation Behavior

Science.gov (United States)

Andriyas, S.; McKee, M.

2012-12-01

Canal operators need information to manage water deliveries to irrigators. Short-term irrigation demand forecasts can potentially valuable information for a canal operator who must manage an on-demand system. Such forecasts could be generated by using information about the decision-making processes of irrigators. Bayesian models of irrigation behavior can provide insight into the likely criteria which farmers use to make irrigation decisions. This paper develops a Bayesian belief network (BBN) to learn irrigation decision-making behavior of farmers and utilizes the resulting model to make forecasts of future irrigation decisions based on factor interaction and posterior probabilities. Models for studying irrigation behavior have been rarely explored in the past. The model discussed here was built from a combination of data about biotic, climatic, and edaphic conditions under which observed irrigation decisions were made. The paper includes a case study using data collected from the Canal B region of the Sevier River, near Delta, Utah. Alfalfa, barley and corn are the main crops of the location. The model has been tested with a portion of the data to affirm the model predictive capabilities. Irrigation rules were deduced in the process of learning and verified in the testing phase. It was found that most of the farmers used consistent rules throughout all years and across different types of crops. Soil moisture stress, which indicates the level of water available to the plant in the soil profile, was found to be one of the most significant likely driving forces for irrigation. Irrigations appeared to be triggered by a farmer's perception of soil stress, or by a perception of combined factors such as information about a neighbor irrigating or an apparent preference to irrigate on a weekend. Soil stress resulted in irrigation probabilities of 94.4% for alfalfa. With additional factors like weekend and irrigating when a neighbor irrigates, alfalfa irrigation

Evaluation model development for sprinkler irrigation uniformity ...

African Journals Online (AJOL)

use

Sprinkle and trickle irrigation. The. Blackburn Press, New Jersey, USA. Li JS, Rao MJ (1999). Evaluation method of sprinkler irrigation nonuniformity. Trans. CSAE. 15(4): 78-82. Lin Z, Merkley GP (2011). Relationships between common irrigation application uniformity indicators. Irrig Sci. Online First™, 27 January. 2011.

76 FR 45693 - Safety Zone; San Diego POPS Fireworks, San Diego, CA

Science.gov (United States)

2011-08-01

...-AA00 Safety Zone; San Diego POPS Fireworks, San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary... San Diego Bay in support of the San Diego POPS Fireworks. This safety zone is necessary to provide for... of the waterway during scheduled fireworks events. Persons and vessels will be prohibited from...

Survey the Effects of Partial Root Zone Deficit Irrigation and Deficit Irrigation on Quantitative, Qualitative and Water Use Efficiency of Pomegranate

Directory of Open Access Journals (Sweden)

mohammad saeed tadaion

2017-12-01

Full Text Available Introduction: One of the latest efficient methods on increment of water use efficiency that confirmed by many scientists all over the world is deficit and alternative partial root zone deficit irrigation. In this experiment the effect of deficit and alternative partial root zone deficit irrigation on fruit yield, quality and water use efficiency of pomegranate (Punicagranatum (L. cv. Zarde-anar were investigatedin Arsenjan semi-arid region. Materials and Methods: The experiment was carried out in a constant plots and randomized complete block design (RCBD with four replicationsin five years.Treatmentswere 1- full flood irrigation (100 percent crop water requirement (T1 2- flood irrigation with 100 percent crop water requirement as alternate partial root-zone irrigation(every irrigation conducted on one side of tree (T2 3- flood irrigation with 50 percent crop water requirement as regular deficit irrigation (T3 4- full two-side drip irrigation(with regard to crop water requirement (eight drippers with twolit/hour flow by two different individual networks (T4 5- alternate partial root-zone drip irrigation with 100 percent crop water requirement (T5 6- regular deficit drip irrigation with 50 percent crop water requirement (T6 in every irrigation period. Each experimental treatment includes four trees and 96 similar twelve years old trees overall. Cultivation practice was conducted similarly on all of the trees. Results and Discussion: Results showed that the highest yield and water use efficiency based on statistical analysis belong to both PRD treatments i.e. alternate partial root-zone drip irrigation with 100 percent crop water requirement and alternate partial root-zone flood irrigation with 100 percent crop water requirement, respectively, that both of them decreased water requirement for irrigation up to 35 and 50 percent in comparison tocontrol. Application of partial root drying irrigation on both traditional flood irrigation and drip

Irrigation as an Historical Climate Forcing

Science.gov (United States)

Cook, Benjamin I.; Shukla, Sonali P.; Puma, Michael J.; Nazarenko, Larissa S.

2014-01-01

Irrigation is the single largest anthropogenic water use, a modification of the land surface that significantly affects surface energy budgets, the water cycle, and climate. Irrigation, however, is typically not included in standard historical general circulation model (GCM) simulations along with other anthropogenic and natural forcings. To investigate the importance of irrigation as an anthropogenic climate forcing, we conduct two 5-member ensemble GCM experiments. Both are setup identical to the historical forced (anthropogenic plus natural) scenario used in version 5 of the Coupled Model Intercomparison Project, but in one experiment we also add water to the land surface using a dataset of historically estimated irrigation rates. Irrigation has a negligible effect on the global average radiative balance at the top of the atmosphere, but causes significant cooling of global average surface air temperatures over land and dampens regional warming trends. This cooling is regionally focused and is especially strong in Western North America, the Mediterranean, the Middle East, and Asia. Irrigation enhances cloud cover and precipitation in these same regions, except for summer in parts of Monsoon Asia, where irrigation causes a reduction in monsoon season precipitation. Irrigation cools the surface, reducing upward fluxes of longwave radiation (increasing net longwave), and increases cloud cover, enhancing shortwave reflection (reducing net shortwave). The relative magnitude of these two processes causes regional increases (northern India) or decreases (Central Asia, China) in energy availability at the surface and top of the atmosphere. Despite these changes in net radiation, however, climate responses are due primarily to larger magnitude shifts in the Bowen ratio from sensible to latent heating. Irrigation impacts on temperature, precipitation, and other climate variables are regionally significant, even while other anthropogenic forcings (anthropogenic aerosols

33 CFR 165.754 - Safety Zone: San Juan Harbor, San Juan, PR.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety Zone: San Juan Harbor, San Juan, PR. 165.754 Section 165.754 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Zone: San Juan Harbor, San Juan, PR. (a) Regulated area. A moving safety zone is established in the...

Colostomy irrigation: are we offering it enough?

Science.gov (United States)

Woodhouse, Fran

This article discusses the use of irrigation for suitable colostomists and reasons why it can have a very positive effect on lifestyle. While it is evidence-based it also includes anecdotal tips from patients who irrigate. The suitability of patients to irrigate and ways to 'get started' with irrigation are discussed.

A scintigraphic study of colostomy irrigation

Energy Technology Data Exchange (ETDEWEB)

Yasuda, Shinji; Fujii, Hisao; Nakano, Hiroshige (Nara Medical Univ., Kashihara (Japan))

1991-09-01

Colostomy irrigation was investigated by colonoscintigraphy. Twelve rectal cancer and one sigmoid colon cancer patients were examined. The tepid water whose volume was determined by barium enema was mixed with {sup 99m}Tc-DTPA. Dynamic scanning was started on commencement of colostomy irrigation. The sampling time was 3 seconds and scanning was performed for 30 minutes. The mean volume of remnant colon as measured by barium enema was 650 ml. The mean number of mass movements was 4.3. The mean evacuation time was 11 minutes 56 seconds and the mean half emptying time was calculated to be 9.5 minutes. The evacuation time in the patients who underwent colostomy irrigation for more than 2 years was greater than that in the patients who underwent irrigation for less than 2 years. Colonic motility was thought to have weakened. The half emptying time and the number of mass movements in the patients whose irrigation water went into the terminal ileum was more than that in the patients whose irrigation water was within the colon and cecum. Irrigation water which went into the terminal ileum was caused evacuation after the contents of the remnant colon were washed out. In conclusion, patients should have their colostomy irrigated with the tepid water, volume is determined by barium enema. Furthermore single infusion of the water is recommended. (author).

A scintigraphic study of colostomy irrigation

International Nuclear Information System (INIS)

Yasuda, Shinji; Fujii, Hisao; Nakano, Hiroshige

1991-01-01

Colostomy irrigation was investigated by colonoscintigraphy. Twelve rectal cancer and one sigmoid colon cancer patients were examined. The tepid water whose volume was determined by barium enema was mixed with 99m Tc-DTPA. Dynamic scanning was started on commencement of colostomy irrigation. The sampling time was 3 seconds and scanning was performed for 30 minutes. The mean volume of remnant colon as measured by barium enema was 650 ml. The mean number of mass movements was 4.3. The mean evacuation time was 11 minutes 56 seconds and the mean half emptying time was calculated to be 9.5 minutes. The evacuation time in the patients who underwent colostomy irrigation for more than 2 years was greater than that in the patients who underwent irrigation for less than 2 years. Colonic motility was thought to have weakened. The half emptying time and the number of mass movements in the patients whose irrigation water went into the terminal ileum was more than that in the patients whose irrigation water was within the colon and cecum. Irrigation water which went into the terminal ileum was caused evacuation after the contents of the remnant colon were washed out. In conclusion, patients should have their colostomy irrigated with the tepid water, volume is determined by barium enema. Furthermore single infusion of the water is recommended. (author)

Alleviating dam impacts along the transboundary Se San River in northeast Cambodia : a review of the rapid environmental impact assessment on the Cambodian part of the Se San River due to hydropower development in Vietnam (July 2007 version)

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-02-15

Probe International has reviewed 2 reports regarding the environmental impact assessment (EIA) on the Cambodian part of the Se San River resulting from hydropower development in Vietnam. Both reports were prepared for Electricity of Vietnam (EVN), the project owner and developer. The operation of 3 large hydro dams on the upper Se San River has disrupted flow in downstream Cambodia where more than 28,000 people depend on the river for drinking water, irrigation, fishing, livestock watering and transportation. Probe International's focus is on mitigating and compensating for affected communities in downstream Cambodia. Their review of the EIAs recommends that Electricity of Vietnam consider switching from peaking to base load operations at its upper Se San hydro dams to mitigate the impacts in downstream Cambodia. The downstream impacts of EVN dams on the Se San River include loss of life, property, livelihood and habitat; malnutrition; loss of wet season rice production; reduced fish catches; food security at risk; loss of fish protein; loss of river bank agriculture; reduced availability of plants for food and medicine; river bank erosion; reservoir erosion and downstream turbidity; increased transportation risks; loss of fisheries habitat; increased pressure on upland forests; disrupted riverine ecosystem; and disrupted fish migration. The EIA recommendations include the re-regulation of the Se San 4A reservoir; operational changes to reduce downstream fluctuations and erosion; monitoring impact of operations on water quantity and quality downstream; algal monitoring; establishment of early warning system for spillway release; prolonging the wet season filling of the reservoir; reducing nutrient inputs to the rivers and reservoirs and a fish stocking program. 6 figs., 1 appendix.

Impacts of Irrigation on the Heat Fluxes and Near-Surface Temperature in an Inland Irrigation Area of Northern China

Directory of Open Access Journals (Sweden)

Li Jiang

2014-03-01

Full Text Available Irrigated agriculture has the potential to alter regional to global climate significantly. We investigate how irrigation will affect regional climate in the future in an inland irrigation area of northern China, focusing on its effects on heat fluxes and near-surface temperature. Using the Weather Research and Forecasting (WRF model, we compare simulations among three land cover scenarios: the control scenario (CON, the irrigation scenario (IRR, and the irrigated cropland expansion scenario (ICE. Our results show that the surface energy budgets and temperature are sensitive to changes in the extent and spatial pattern of irrigated land. Conversion to irrigated agriculture at the contemporary scale leads to an increase in annual mean latent heat fluxes of 12.10 W m−2, a decrease in annual mean sensible heat fluxes of 8.85 W m−2, and a decrease in annual mean temperature of 1.3 °C across the study region. Further expansion of irrigated land increases annual mean latent heat fluxes by 18.08 W m−2, decreases annual mean sensible heat fluxes by 12.31 W m−2, and decreases annual mean temperature by 1.7 °C. Our simulated effects of irrigation show that changes in land use management such as irrigation can be an important component of climate change and need to be considered together with greenhouse forcing in climate change assessments.

Agriculture Irrigation and Water Use

OpenAIRE

Bajwa, Rajinder S.; Crosswhite, William M.; Hostetler, John E.; Wright, Olivia W.; United States Department of Agriculture, Economic Research Service

1992-01-01

The 17 Western States, plus Arkansas, Florida, and Louisiana, account for 91 percent of all U.S. irrigated acreage, with the Western States alone contributing over 85 percent. This report integrates data on the distribution, characteristics, uses, and management of water resources from a wide variety of data sources. The report includes charts and tables on water use in irrigation; farm data comparing selected characteristics of irrigated and nonirrigated farms; and data on water applicatio...

Online decision support system for surface irrigation management

Science.gov (United States)

Wang, Wenchao; Cui, Yuanlai

2017-04-01

Irrigation has played an important role in agricultural production. Irrigation decision support system is developed for irrigation water management, which can raise irrigation efficiency with few added engineering services. An online irrigation decision support system (OIDSS), in consist of in-field sensors and central computer system, is designed for surface irrigation management in large irrigation district. Many functions have acquired in OIDSS, such as data acquisition and detection, real-time irrigation forecast, water allocation decision and irrigation information management. The OIDSS contains four parts: Data acquisition terminals, Web server, Client browser and Communication system. Data acquisition terminals are designed to measure paddy water level, soil water content in dry land, ponds water level, underground water level, and canals water level. A web server is responsible for collecting meteorological data, weather forecast data, the real-time field data, and manager's feedback data. Water allocation decisions are made in the web server. Client browser is responsible for friendly displaying, interacting with managers, and collecting managers' irrigation intention. Communication system includes internet and the GPRS network used by monitoring stations. The OIDSS's model is based on water balance approach for both lowland paddy and upland crops. Considering basic database of different crops water demands in the whole growth stages and irrigation system engineering information, the OIDSS can make efficient decision of water allocation with the help of real-time field water detection and weather forecast. This system uses technical methods to reduce requirements of user's specialized knowledge and can also take user's managerial experience into account. As the system is developed by the Browser/Server model, it is possible to make full use of the internet resources, to facilitate users at any place where internet exists. The OIDSS has been applied in

Colonic irrigation for defecation disorders after dynamic graciloplasty.

Science.gov (United States)

Koch, Sacha M; Uludağ, Ozenç; El Naggar, Kadri; van Gemert, Wim G; Baeten, Cor G

2008-02-01

Dynamic graciloplasty (DGP) improves anal continence and quality of life for most patients. However, in some patients, DGP fails and fecal incontinence is unsolved or only partially improved. Constipation is also a significant problem after DGP, occurring in 13-90%. Colonic irrigation can be considered as an additional or salvage treatment for defecation disorders after unsuccessful or partially successful DGP. In this study, the effectiveness of colonic irrigation for the treatment of persistent fecal incontinence and/or constipation after DGP is investigated. Patients with defecation disorders after DGP visiting the outpatient clinic of the University Hospital Maastricht were selected for colonic irrigation as additional therapy or salvage therapy in the period between January 1999 and June 2003. The Biotrol(R) Irrimatic pump or the irrigation bag was used for colonic irrigation. Relevant physical and medical history was collected. The patients were asked to fill out a detailed questionnaire about colonic irrigation. Forty-six patients were included in the study with a mean age of 59.3 +/- 12.4 years (80% female). On average, the patients started the irrigation 21.39 +/- 38.77 months after the DGP. Eight patients started irrigation before the DGP. Fifty-two percent of the patients used the irrigation as additional therapy for fecal incontinence, 24% for constipation, and 24% for both. Irrigation was usually performed in the morning. The mean frequency of irrigation was 0.90 +/- 0.40 times per day. The mean amount of water used for the irrigation was 2.27 +/- 1.75 l with a mean duration of 39 +/- 23 min. Four patients performed antegrade irrigation through a colostomy or appendicostomy, with good results. Overall, 81% of the patients were satisfied with the irrigation. Thirty-seven percent of the patients with fecal incontinence reached (pseudo-)continence, and in 30% of the patients, the constipation completely resolved. Side effects of the irrigation were

The Impact of Regular and Periodic Irrigation on the Fertility and Productivity of an Ordinary Chernozem of the Azov Irrigation System

Science.gov (United States)

Shchedrin, V. N.

2016-02-01

The effect of regular and periodic irrigation on the fertility and productivity of an ordinary chernozem cultivated under different conditions within the same cereal-fodder crop rotation is discussed. The investigation object is located in the area of the Azov irrigation system on the second terrace of the Don River in Rostov oblast. Irrigation water for the system is taken from the Veselovsk water reservoir. Its salinity is 1.7-2.1 g/dm3, and the salt composition is sulfate-sodium. The field experiments were performed in 2006-2013 on three experimental plots. Two of them were regularly irrigated; the third plot was periodically irrigated with alternation of 2-year-long periods with and without irrigation. Our study proved that periodic irrigation could be applied in the chernozemic zone. This new irrigation mode contributes to the preservation of the natural soil-forming process and stops the development of unfavorable processes typical of the lands irrigated with water of inadequate quality. In eight years of cultivation of the ordinary chernozem with periodic irrigation, the soil humus content increased by 10% (from 3.80 to 4.15%), and the yield reached 66.0 t/ha of fodder units. This was 9% higher than the yield obtained upon regular irrigation without agroameliorative measures and 12% lower than the yield upon regular irrigation in combination with soil-protective measures. Our data suggest that periodic irrigation is promising for the chernozemic zone, because it ensures lower water loads and preservation of the irrigated chernozems.

Fluctuación poblacional del picudo negro (Cosmopolites sordidus Germar del plátano (Musa AAB en San Carlos, Costa Rica

Directory of Open Access Journals (Sweden)

Carlos Muñoz Ruiz

2007-05-01

Full Text Available Se evaluó el efecto de las lesiones provocadas por el picudo negro (Cosmopolites sordidus, Germar en una plantación de plátano “Curraré”, según dos sistemas de producción: el tradicional y el convencional, en la zona de San Carlos, Costa Rica. El proyecto se ordenó en un diseño experimental irrestricto al azar, con cuatro repeticiones. Se evaluaron las variables vegetativas (altura de la planta, diámetro del pseudotallo, durante el desarrollo de la plantación (primer año y las variables productivas (peso del racimo, calibre y longitud del dedo central de la segunda mano en el momento de cosechar los racimos. También se evalúo la eficiencia de dos métodos de muestreo y captura de adultos del picudo negro, la trampa tipo “disco” y con feromona Cosmolure ®, de Chem Tica S A. en potes de plástico enterradas en el suelo. No hubo diferencias significativas en el número de captura en ambos métodos de muestreo. Tampoco se pudo encontrar ninguna relación del clima con el número de individuos capturados en este experimento. El daño del insecto en el cultivo de plátano fue evaluado según la metodología o escala de Vilardebo (1971, y se obtuvieron resultados de lesiones inferiores al 5%, los que se consideraron no perjudiciales económicamente para la actividad platanera en la zona de influencia del estudio. Se utilizó también la escala de Bridge, la cual no fue funcional en este estudio.

21 CFR 876.5895 - Ostomy irrigator.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ostomy irrigator. 876.5895 Section 876.5895 Food... DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Therapeutic Devices § 876.5895 Ostomy irrigator. (a) Identification. An ostomy irrigator is a device that consists of a container for fluid, tubing with a cone-shaped...

Structure and thermodynamics of nonideal solutions of colloidal particles. Investigation of salt-free solutions of human serum albumin by using small-angle neutron scattering and Monte Carlo simulation

DEFF Research Database (Denmark)

Sjøberg, B.; Mortensen, K.

1997-01-01

Carlo simulation, to study salt-free solutions of human serum albumin (HSA) in the concentration range up to 0.26 g ml(-1). The model calculations of the theoretical SANS intensities are quite general, thus avoiding the approximation that the relative positions and orientations of the particles......-shaped potential which is spherically oriented around the particles. The combination of SANS and statistical thermodynamics also allows a determination of the nonideal part of the chemical potential and the activity coefficient of HSA. As expected the activity coefficient deviates strongly from the value one...

Comparison of traditional and ET-based irrigation scheduling of surface-irrigated cotton in the arid southwestern USA

Science.gov (United States)

The use of irrigation scheduling tools to produce cotton under-surface irrigation in the arid southwesternUSA is minimal. In the State of Arizona, where traditional irrigation scheduling is the norm, producersuse an average of 1460 mm annually to grow a cotton crop. The purpose of this paper was to ...

Manejo de Sigatoka negra (Mycosphaerella Fijiensis var. Difformis Morelet en plátano cv. “Curraré” en San Carlos, Zona Norte

Directory of Open Access Journals (Sweden)

Carlos Muñoz Ruiz

2005-05-01

Full Text Available Se evaluaron los diferentes productos químicos, utilizados en el control de Sigatoka negra en banano, en el cultivo de plátano, en la zona de Santa Clara de San Carlos. Uno de los principales objetivos fue generar un programa de manejo químico de la enfermedad para la zona de San Carlos, posible de ser transferido a otras zonas plataneras del país; el otro objetivo fue establecer las bases para automatizar las actividades culturales de manejo de plantaciones de musáceas, mediante la creación de un Software para computadora y asequible por internet. Para el primer objetivo, se logró establecer que genéticamente el plátano es más resistente a la enfermedad y, por ser un cultivo donde hasta el momento, no se ha sobrepasado el uso de funguicidas como sucede en el banano, se pueden utilizar sin problema los productos protectantes mas comunes, como el Vondozeb y el Ridodur, tanto en aceite como en agua, así como el aceite puro a 7 litros/ha, presentando un efecto aceptable en el control de la infección de Mycospharella. Los productos sistémicos utilizados mostraron su eficiencia aunque, por su costo, no se sugiere su uso en plátano, solo para casos de emergencia. La mezcla de protectantes con sistémicos y aceite (cocteles, se consideran muy efectivos pero innecesarios para ser utilizados en plátano en forma comercial. Para esta evaluación se hicieron 35 aplicaciones o semanas de evaluación, en dos periodos climatológicos (verano e invierno de enero a septiembre del 2001, combinadas con las prácticas culturales tradicionales de deshoja, deshija, fertilización, y el monitoreo, utilizando la escala de signos visuales de 6 puntos de Stover y el método francés. Se evaluaron las variables: Hojas por planta (H/P, Hoja mas joven enferma (HMJE y Porcentaje ponderado de infecci��n (PPI, para cada tipo de grupo químico evaluado. La variable H/P, en la mayoría de los grupos se inició con un mínimo de 3 hojas hasta un máximo de 14

75 FR 43958 - Turlock Irrigation District and Modesto Irrigation District; Notice of Application for Amendment...

Science.gov (United States)

2010-07-27

... to the Turlock Irrigation District's Tuolumne Substation; (2) 23-mile-long, 69-kV Don Pedro-Hawkins Line extending from the Don Pedro switchyard to the Turlock Irrigation District's Hawkins Substation...

Measuring Transpiration to Regulate Winter Irrigation Rates

Energy Technology Data Exchange (ETDEWEB)

Samuelson, Lisa [Auburn University

2006-11-08

Periodic transpiration (monthly sums) in a young loblolly pine plantation between ages 3 and 6 was measured using thermal dissipation probes. Fertilization and fertilization with irrigation were better than irrigation alone in increasing transpiration of young loblolly pines during winter months, apparently because of increased leaf area in fertilized trees. Irrigation alone did not significantly increase transpiration compared with the non-fertilized and non-irrigated control plots.

Transformaciones del modelo Neogranadino de parroquialización. El caso de la Parroquia San Francisco Xavier de Piedecuesta

Directory of Open Access Journals (Sweden)

Luis Rubén Pérez Pinzón

2013-01-01

Full Text Available El artículo analiza los fundamentos canónigos, las razones virreinales y los rituales eclesiásticos que justificaron las fundaciones parroquiales del siglo XVIII. Para ello se enfatiza en el modelo de urbanismo de las autoridades borbónicas que sustituyó la práctica de fundaciones de ciudades y villas de los siglos XVI y XVII a partir de capitulaciones. Modelo de necesidades demostradas, visitas a las instituciones virreinales y verificación de méritos que se puede comprobar desde el caso de la parroquia moderna de San Francisco Xavier del Pie de la Cuesta (Santander, Colombia, la cual pasó de ser un sitio irregular a la próspera Villa de San Carlos del siglo XIX.

Management of poor quality irrigation water

International Nuclear Information System (INIS)

Change, M.H.; Leghari, A.M.; Sipio, Q.A.

2000-01-01

The effect of poor quality drainage effluent on moderately saline sodic, medium textured soil at different growth stages of wheat and cotton is reported. The irrigation treatments were: I) All canal irrigations, II) one irrigation of 75 mm with saline drainage effluent (EC = 3 dS m1) after four weeks sowing of the crop, III) one irrigation of 75 mm with saline drainage effluent after seven weeks sowing of the crop, and IV) one irrigation of 75 mm with saline drainage effluent after ten weeks sowing of the crop. The treatments receiving saline water gave significant decrease in crop yields as compared to canal irrigation treatment. The higher yield of wheat and seed cotton was recorded T1 followed by T2, T3 and T4. The trend of produce was T1< T2< T3< T4 respectively. Electrical conductivity of the soil (Ece) in T1 was decreased and in other three treatments was increased, whereas, pH decreased in T1 and T2. The SAR of soil decreased in all the treatments as compared with initial values. Treatment receiving an irrigation with saline water after four weeks of sowing (T2) was better in reducing soil salinity as compared to treatments receiving such water after 7 or 10 weeks os sowing. Poor quality water (EC = 3 d Sm/sup -1/) can be managed for irrigation after four weeks of swing of crops provided certain soil and water management practices like good seed bed preparation and proper drainage measures are adopted. (author)

Uncertainties in modelling the climate impact of irrigation

Science.gov (United States)

de Vrese, Philipp; Hagemann, Stefan

2017-11-01

Irrigation-based agriculture constitutes an essential factor for food security as well as fresh water resources and has a distinct impact on regional and global climate. Many issues related to irrigation's climate impact are addressed in studies that apply a wide range of models. These involve substantial uncertainties related to differences in the model's structure and its parametrizations on the one hand and the need for simplifying assumptions for the representation of irrigation on the other hand. To address these uncertainties, we used the Max Planck Institute for Meteorology's Earth System model into which a simple irrigation scheme was implemented. In order to estimate possible uncertainties with regard to the model's more general structure, we compared the climate impact of irrigation between three simulations that use different schemes for the land-surface-atmosphere coupling. Here, it can be shown that the choice of coupling scheme does not only affect the magnitude of possible impacts but even their direction. For example, when using a scheme that does not explicitly resolve spatial subgrid scale heterogeneity at the surface, irrigation reduces the atmospheric water content, even in heavily irrigated regions. Contrarily, in simulations that use a coupling scheme that resolves heterogeneity at the surface or even within the lowest layers of the atmosphere, irrigation increases the average atmospheric specific humidity. A second experiment targeted possible uncertainties related to the representation of irrigation characteristics. Here, in four simulations the irrigation effectiveness (controlled by the target soil moisture and the non-vegetated fraction of the grid box that receives irrigation) and the timing of delivery were varied. The second experiment shows that uncertainties related to the modelled irrigation characteristics, especially the irrigation effectiveness, are also substantial. In general the impact of irrigation on the state of the land

Modeling a Sustainable Salt Tolerant Grass-Livestock Production System under Saline Conditions in the Western San Joaquin Valley of California

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Stephen R. Kaffka

2013-09-01

Full Text Available Salinity and trace mineral accumulation threaten the sustainability of crop production in many semi-arid parts of the world, including California’s western San Joaquin Valley (WSJV. We used data from a multi-year field-scale trial in Kings County and related container trials to simulate a forage-grazing system under saline conditions. The model uses rainfall and irrigation water amounts, irrigation water quality, soil, plant, and atmospheric variables to predict Bermuda grass (Cynodon dactylon (L. Pers. growth, quality, and use by cattle. Simulations based on field measurements and a related container study indicate that although soil chemical composition is affected by irrigation water quality, irrigation timing and frequency can be used to mitigate salt and trace mineral accumulation. Bermuda grass yields of up to 12 Mg dry matter (DM·ha−1 were observed at the field site and predicted by the model. Forage yield and quality supports un-supplemented cattle stocking rates of 1.0 to 1.2 animal units (AU·ha−1. However, a balance must be achieved between stocking rate, desired average daily gain, accumulation of salts in the soil profile, and potential pollution of ground water from drainage and leaching. Using available weather data, crop-specific parameter values and field scale measurements of soil salinity and nitrogen levels, the model can be used by farmers growing forages on saline soils elsewhere, to sustain forage and livestock production under similarly marginal conditions.

Evaluation of Modern Irrigation Techniques with Brackish Water

OpenAIRE

Aboulila, Tarek Selim

2012-01-01

Modern irrigation techniques are becoming increasingly important in water-scarce countries especially in arid and semiarid regions. Higher crop production and better water use efficiency are usually achieved by drip irrigation as compared to other irrigation methods. Furthermore, by using drip irrigation simultaneously with brackish irrigation water, some of the water stress due to shortage of fresh water resources can be managed. The objective of the current study was to investigate the infl...

Exportación a Nueva España de manufacturas de la Real Fábrica de Cristales de San Ildefonso (1760-1763

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María Teresa Ruiz Alcón

1994-01-01

Full Text Available La Real Fábrica de Cristales de San Ildefonso, cuyos orígenes se remontan al año 1727, fecha en la que Felipe V concedió una licencia a los maestros catalanes Buena Ventura Sit y Carlos Sac para instalar un taller de manufactura de vidrio en el Real Sitio de San Ildefonso, pasó a ser Real Fábrica de Cristales y Espejos en 1745 por iniciativa del monarca, con el ánimo de fomentar la producción nacional y evitar la importación de productos extranjeros. La fábrica dependía directamente de la Corona y administrativamente, de la Secretaría de Estado.

Evaluation some Forage Legumes in Limited Irrigation Condition

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Hassan Moniri Far

2015-11-01

Full Text Available Forage legumes respond differently to limited irrigation regimes. Their evaluation may, thus, help to select drought tolerant types for limited irrigation conditions. In this study four type of forage legume were studied for two years in Tikma-Dash Research Station of East Azarbaijan Agricultural and Natural Research Center, Tabriz, Iran, in a randomized complete block design using split-plot experiment in 2011-2013 years. Irrigation regimes (without irrigation, one irrigation and two irrigations were assigned to main plots and four forage types (hairy vetch, grass pea, Pannonica sativa and lathyrus were assigned to subplots. The results of analysis of variance showed that the effect of irrigation on plant height, number of shoots, leaf area and plant fresh and dry weights were not significant. Howere, legume types affected these traits significantly (P≤0.01. The effect of irrigation levels and legume types on protein content of hay were significant (P

Optimization of modern irrigation for biosaline agriculture

International Nuclear Information System (INIS)

Shahid, S.A.; Hasbini, B.

2007-01-01

Supplementation water is a must to offset the water requirement to produce profitable crops in most arid and semiarid zones, where fresh water resources are insufficient to meet the pressure of irrigated agriculture. This necessitates the use of poor quality water resources. These waters if not properly managed and used can cause serious soil related problems (salinity, sodicity, destruction of soil structure) in addition to decline in crop yields. Biosaline agriculture (using saline water on saline soils to grow salt-tolerant crops) becomes the only option for the farmer when both soil and water resources are saline and the water resource is scarce. In this regards key design considerations must be taken into account when irrigating with salty waters to optimize water uses and to reduce subsequent soil salinity development. Sprinkler irrigation systems are commonly used in irrigation of large-scale irrigational production systems. However they tend to concentrate salts on the leaves of plants. For this reason discharge and degree of overlap between consecutive sprinkler heads, are key design parameters when applying salty waters. Trickle irrigation is the most efficient system and is gaining importance in the GCC countries in the agriculture and landscape irrigation. The objective of this study was to optimize modern irrigation systems through development of design standards for drip (emitters spacing) and sprinkler irrigation systems (single head jet and overlapping) by applying saline water. The effect of emitter spacing (drip) and overlapping (sprinkler) were tested for the formation of salt contours in soil. The leaching ratio (LR) is the overall soil sanity within rhizosphere divided by the average irrigation water salinity. In this study LR is used to evaluate the effectiveness of irrigation systems in developing soil sanity. From the present investigations it is concluded that when using saline water for irrigation, the soil sanity development can be

Ancestral irrigation method by kanis in Bolivia

Science.gov (United States)

Roldán-Cañas, José; Chipana, René; Fátima Moreno-Pérez, María

2015-04-01

Irrigation in the Andean region is an ancient practice. For centuries, farmers were able to use the waters of rivers, lakes and springs to complement or supplement the scarce rainfall regime. The inter-Andean valleys of the Department of La Paz are the best areas for the study of traditional irrigation systems. This work has been carried out in the community of Jatichulaya located in te town of Charazani, 300 km from the city of La Paz, which lies 3250 meters above sea level. The annual rainfall ranges around 450 mm distributed mainly between the months of December to March. Therefore, water is needed to achieve adequate crop yields. The traditional irrigation system is done by the method of Kanis, consisting of a surface irrigation already developed by traditional Andean cultures of the country, in harmony with the ecological and productive characteristics of the area. Water enters the irrigation plot through a main channel (mama kani) from which the secondary channels (juchuy kanis) are derived. The fundamental characteristic of this irrigation is that these channels are open at the same time the water enters into the plot. The system works properly, adapting to the topography of the area. The irrigation method practiced in this community does not cause water erosion of soils because water management within the plot is based on the ancient knowledge of farmers following the contour lines. This practice allows good irrigation development and soil protection without causing any problems. However, it was evident a high use of labor in irrigation practice. Irrigation scheduling is done according to requests made by the irrigators in a given period. Delivering of water to the farmers is made by the so-called Water Agent (Agente de Aguas) or person in charge of the distribution of water. The Water Agent is elected annually and its functions include the maintenance and care of all system waterworks. The period between August and January is the highest water demand and

Converting Surface Irrigation to Pressurized Irrigation Systems and its Effecton Yield of OrangeTrees (Case Study:North of Khouzestan

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M. Khorramian

2017-01-01

Full Text Available Introduction: North of the Khouzestan is one of the most important citrus production center. Usually border irrigation is used to irrigate citrus in this area. This system has generally low application efficiency. Several investigations in other arid region have demonstrated in addition to improved irrigation efficiency with low-volume pressurized irrigation systems, citrus trees have adapted with these new irrigation systems. However limited information exists on the performance of mature orchards converted from border surface irrigation to pressurized irrigation systems. Therefore, the current research was conducted to evaluate the feasibility of converting surface irrigation to pressurized irrigation systems on mature citrus trees in climate conditions of North Khouzestan. Materials and Methods: This study was conducted during three years at Safiabad Agricultural Research Center to evaluate the yield of citrus trees and the quality of fruits for two Marss and Valencia varieties which grow 7 years previously with surface irrigation and converted to pressurized irrigation systems. The treatments consisted of six irrigation methods including Overhead sprinkle irrigation (OHSI, Under tree sprinkle irrigation(UTSI, Trickle irrigation(TI(six 8 L/h Netafim emitters, Microjet irrigation (MI(two 180 microjet were located under canopy near of the trunk at opposite sides of trunk,Bubbler irrigation(BI(a single located under the canopy of each treeandSurface irrigation(SI method.Soil texture was clay loam well drained without salinity(ECe=0.69ds m-1, with 1.25 percent organic carbon. The experimental design was completely randomized design. The trees were irrigated during spring and summer seasons. For calculating irrigation water depth in TI, MI and BI systems, daily evaporation from a class A evaporation pan of the Safiabad weather station (nearby the experimental field was collected, and evapotranspiration of the citrus trees was calculated applying a

GSM BASED IRRIGATION CONTROL AND MONITORING SYSTEM

OpenAIRE

GODFREY A. MILLS; STEPHEN K. ARMOO; AGYEMAN K. ROCKSON; ROBERT A. SOWAH; MOSES A. ACQUAH

2013-01-01

Irrigated agriculture is one of the primary water consumers in most parts of the world. With developments in technology, efforts are being channeled into automation of irrigation systems to facilitate remote control of the irrigation system and optimize crop production and cost effectiveness. This paper describes an on-going work on GSM based irrigation monitoring and control systems. The objective of the work is to provide an approach that helps farmers to easily access, manage and regulate ...

Comparative efficiency of trickle and furrow irrigation

International Nuclear Information System (INIS)

Hanif, M.; Qureshi, R.H.; Sandhu, G.R.

1976-01-01

Comparison of furrow and trickle methods of irrigation to know their relative efficiency with respect to water applied and fertilizer used on tomatoes, cauliflower and lettuce as test crops using canal water, showed a significant saving of about 44 and 41 per cent respectively for irrigation water and fertilizer applied with trickle as compared to furrow irrigation. Trickle irrigated crops also showed a better response as regards the rate of survival, crop growth and time of maturity

Minería, conflicto y mediadores locales: Minera San Xavier en Cerro de San Pedro, México Mineira, conflito e mediadores locais: Minera San Xavier em Cerro de San Pedro Mining, conflict and local brokers: Minera San Xavier in Cerro de San Pedro

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Hernán Horacio Schiaffini

2011-12-01

Full Text Available Este trabajo indaga en las instancias de mediación que intervienen en la articulación de procesos económicos de gran escala y su puesta en práctica local. Basándonos en el conflicto que se produjo en el Municipio de Cerro de San Pedro (San Luis Potosí, México entre la empresa Minera San Xavier y el Frente Amplio Opositor (FAO a la misma, aplicamos el método etnográfico con el objetivo de describir las estructuras locales de mediación política y analizar sus prácticas y racionalidad. Intentamos demostrar así la importancia de los factores políticos locales en las vinculaciones entre estado, empresa y población.Este trabalho indaga nas instâncias de mediação que intervêm em processos econômicos de grande escala e sua posta em prática local. Baseando-nos no conflito no Cerro de San Pedro (San Luis Potosí, México entre a empresa Minera San Xavier e a Frente Amplio Opositor (FAO aplicamos o método etnográfico pra descrever as estruturas de mediação política locais e analisar suas práticas e racionalidade. Tenta-se demonstrar assim a importância dos fatores políticos locais nas vinculações entre estado, empresa e população.This paper investigates in instances of mediation involved in large-scale economic processes and local implementation. Analyzing the conflict in Cerro de San Pedro (San Luis Potosí, México among San Xavier mining company and the Frente Amplio Opositor (FAO, it applies an ethnographic approach to describe the local structures of political mediation and its practices and rationality. The work shows the relevance of local factors in the relationships between State, company and people.

Simón Rodríguez Laso, un clérigo ilustrado en el colegio de San Clemente de los españoles

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Nieto Sánchez, Carlos

2013-06-01

Full Text Available Simón Rodríguez Laso (Montejo, Salamanca, 1751, Bologna, 1821 Doctor of Law for the University of Bologna, Dignity of the Maestrecuela of the Cathedral of Ciudad Rodrigo, Knight of the Order of Carlos III and Rector of the College of San Clemente (Bolonga, Italy from 1788 until his death, in 1821. This article seeks to highlight the Italian stage of a Spanish Enlightenment men, who fought for the survival of a characteristic institution of the Ancien Regime, San Clemente of the Spaniards College, which resisted the offensive of liberalism. The article also underlines Laso´s personality, learned and regalist, he saw off his reformist thinking because of the new ideas that emerged from French Revolution and devoted his life to the Hispanic College of Bologna.Simón Rodríguez Laso (Montejo, Salamanca, 1751, Bolonia, 1821 Doctor en Cánones por la Universidad de Bolonia, dignidad de de maestrescuela de la S. I. catedral de Ciudad Rodrigo, caballero de la Orden de Carlos III y rector del Colegio de San Clemente de Bolonia desde 1788 hasta su muerte en 1821. En este artículo se pretende dar a conocer la etapa italiana de un ilustrado español, que luchó por la supervivencia de una institución característica del Antiguo Régimen, el Colegio de San Clemente de los españoles de Bolonia, que resistió a la ofensiva del liberalismo. En el artículo se quieren también destacar algunos rasgos de la personalidad de Laso, ilustrado y regalista, que vio mitigado su pensamiento reformista por las nuevas ideas que surgieron de la Revolución Francesa y que consagró su vida al Colegio hispánico de Bolonia.

Energy performance of sprinkler irrigated maize, wheat and sunflower in Vigia irrigation district

Energy Technology Data Exchange (ETDEWEB)

Carvalho, Sandra; Rodrigues, Goncalo Caleia; Paredes, Paula; Pereira, Luis S. [Centro de Engenharia dos Biossistemas (CEER/ISA), Lisboa (Portugal)], E-mail: lspereira@isa.utl.pt

2008-07-01

The energy potential of a crop may be evaluated through life cycle assessment methodologies. These refer to the computation of the crop's energy balance and other related indicators, such as the energy ratio and the energetic efficiency, that may be used as to assess how a given irrigated crop may be used for production of biofuel. This study concerns sprinkler irrigated sunflower, wheat and maize crops using data relative to the campaign of 2007 in the Vigia Irrigation District, Alentejo. A model was developed and various scenarios were considered. The modelling results lead to the conclusion that the maize crop is the most efficient in producing energy and sunflower is the least one for all the alternative scenarios considered. (author)

Scenario Studies on Effects of Soil Infiltration Rates, Land Slope, and Furrow Irrigation Characteristics on Furrow Irrigation-Induced Erosion.

Science.gov (United States)

Dibal, Jibrin M; Ramalan, A A; Mudiare, O J; Igbadun, H E

2014-01-01

Furrow irrigation proceeds under several soil-water-furrow hydraulics interaction dynamics. The soil erosion consequences from such interactions in furrow irrigation in Samaru had remained uncertain. A furrow irrigation-induced erosion (FIIE) model was used to simulate the potential severity of soil erosion in irrigated furrows due to interactive effects of infiltration rates, land slope, and some furrow irrigation characteristics under different scenarios. The furrow irrigation characteristics considered were furrow lengths, widths, and stream sizes. The model itself was developed using the dimensional analysis approach. The scenarios studied were the interactive effects of furrow lengths, furrow widths, and slopes steepness; infiltration rates and furrow lengths; and stream sizes, furrow lengths, and slopes steepness on potential furrow irrigation-induced erosion, respectively. The severity of FIIE was found to relate somewhat linearly with slope and stream size, and inversely with furrow lengths and furrow width. The worst soil erosion (378.05 t/ha/yr) was found as a result of the interactive effects of 0.65 m furrow width, 50 m furrow length, and 0.25% slope steepness; and the least soil erosion (0.013 t/ha/yr) was induced by the combined effects of 0.5 l/s, 200 m furrow length, and 0.05% slope steepness. Evidently considering longer furrows in furrow irrigation designs would be a better alternative of averting excessive FIIE.

Irrigation management in organic greenhouse

NARCIS (Netherlands)

Voogt, W.; Balendonck, J.; Berkelmans, R.; Enthoven, N.

2017-01-01

Irrigation in protected cultivation is essential due to the absence of natural precipitation. High evapotranspiration, due to higher temperature and prolonged cropping period, requires ample an adequate supply of water. The water supply in a greenhouse is solely carried out by irrigation and thus

Trash-polluted irrigation: characteristics and impact on agriculture

Science.gov (United States)

Sulaeman, D.; Arif, SS; Sudarmadji

2018-04-01

Trash pollution has been a problem in sustainable water resources management. Trash pollutes not only rivers, lakes and seas, but also irrigation canals and rice fields. This study aimed to identify the characteristics of solid waste (type, time of occurrence and sources of trash) and its impact on agriculture. The study was conducted in four irrigation areas, namely Gamping, Merdiko, Nglaren and Karangploso in Bantul District, Yogyakarta Special Region. We applied the Irrigation Rapid Trash Assessment (IRTA) as our field survey instrument. The results showed that trash was found throughout irrigation canals and rice fields, and the occurrence was influenced by water flow, time and farmer activities. The irrigation was dominantly polluted by plastic trash (52.2%), biodegradable waste (17.91%) and miscellaneous trash (12.3%). The IRTA score showed that Gamping Irrigation Area was at marginal condition, bearing a high risk of disturbing the operation and maintenance of the irrigation canals as well as farmers’ health. Trash in irrigation also generated technical impact of the irrigation operation and maintenance, environmental quality, and social life. This research also offered environmental policy integration approach and water-garbage governance approach as an alternative solution to manage water resources and agriculture in a sustainable manner, under the pressure of increasing amount of trash.

[Optimal irrigation index for cotton drip irrigation under film mulching based on the evaporation from pan with constant water level].

Science.gov (United States)

Shen, Xiao-Jun; Zhang, Ji-Yang; Sun, Jing-Sheng; Gao, Yang; Li, Ming-Si; Liu, Hao; Yang, Gui-Sen

2013-11-01

A field experiment with two irrigation cycles and two irrigating water quotas at squaring stage and blossoming-boll forming stage was conducted in Urumqi of Xinjiang Autonomous Region, Northwest China in 2008-2009, aimed to explore the high-efficient irrigation index of cotton drip irrigation under film mulching. The effects of different water treatments on the seed yield, water consumption, and water use efficiency (WUE) of cotton were analyzed. In all treatments, there was a high correlation between the cotton water use and the evaporation from pan installed above the plant canopy. In high-yield cotton field (including the treatment T4 which had 10 days and 7 days of irrigation cycle with 30.0 mm and 37.5 mm of irrigating water quota at squaring stage and blossoming-boll forming stage, respectively in 2008, and the treatment T1 having 7 days of irrigation cycle with 22.5 mm and 37.5 mm of irrigating water quota at squaring stage and blossoming-boll forming stage, respectively in 2009), the pan-crop coefficient (Kp) at seedling stage, squaring stage, blossoming-boll forming stage, and boll opening stage was 0.29-0.30, 0.52-0.53, 0.74-0.88, and 0.19-0.20, respectively. As compared with the other treatments, T4 had the highest seed cotton yield (5060 kg x hm(-2)) and the highest WUE (1.00 kg x m(-3)) in 2008, whereas T1 had the highest seed cotton yield (4467 kg x hm(-2)) and the highest WUE (0.99 kg x m(-3)) in 2009. The averaged cumulative pan evaporation in 7 days and 10 days at squaring stage was 40-50 mm and 60-70 mm, respectively, and that in 7 days at blossoming-boll forming stage was 40-50 mm. It was suggested that in Xinjiang cotton area, irrigating 45 mm water for seedling emergence, no irrigation both at seedling stage and at boll opening stage, and irrigation was started when the pan evaporation reached 45-65 mm and 45 mm at squaring stage and blossoming-boll stage, respectively, the irrigating water quota could be determined by multiplying cumulative

performance evaluation of sprinkler irrigation system at mambilla

African Journals Online (AJOL)

HOD

ratio (DPR), irrigation productivity (IP), labour requirements and water quality. Standard procedure was ... The exchangeable cations analysis of Kakara irrigation ... Keywords: Tea, irrigation System, Performance Evaluation. 1. INTRODUCTION.

Expanding the Annual Irrigation Maps (AIM) Product to the entire High Plains Aquifer (HPA): Addressing the Challenges of Cotton and Deficit-Irrigated Fields

Science.gov (United States)

Rapp, J. R.; Deines, J. M.; Kendall, A. D.; Hyndman, D. W.

2017-12-01

The High Plains Aquifer (HPA) is the most extensively irrigated aquifer in the continental United States and is the largest major aquifer in North America with an area of 500,000 km2. Increased demand for agricultural products has led to expanded irrigation extent, but brought with it declining groundwater levels that have made irrigation unsustainable in some locations. Understanding these irrigation dynamics and mapping irrigated areas through time are essential for future sustainable agricultural practices and hydrological modeling. Map products using remote sensing have only recently been able to track annual dynamics at relatively high spatial resolution (30 m) for a large portion of the northern HPA. However follow-on efforts to expand these maps to the entire HPA have met with difficulty due to the challenge of distinguishing irrigation in crop types that are commonly deficit- or partially-irrigated. Expanding these maps to the full HPA requires addressing unique features of partially irrigated fields and irrigated cotton, a major water user in the southern HPA. Working in Google Earth Engine, we used all available Landsat imagery to generate annual time series of vegetation indices. We combined this information with climate covariables, planting dates, and crop specific training data to algorithmically separate fully irrigated, partially irrigated, and non-irrigated field locations. The classification scheme was then applied to produce annual maps of irrigation across the entire HPA. The extensive use of ancillary data and the "greenness" time series for the algorithmic classification generally increased accuracy relative to previous efforts. High-accuracy, representative map products of irrigation extent capable of detecting crop type and irrigation intensity within aquifers will be an essential tool to monitor the sustainability of global aquifers and to provide a scientific bases for political and economic decisions affecting those aquifers.

Managing Water Resources for Environmentally Sustainable Irrigated Agriculture in Pakistan

OpenAIRE

Muhammad Afzal

1996-01-01

Pakistan’s agriculture is almost wholly dependent on irrigation and irrigated land supplies more than 90 percent of agricultural production. Irrigation is central to Pakistan’s economy. Massive investments in irrigation contributed to the development of one of the largest Indus Basin Irrigation System. Despite heavy budgetary inputs in irrigation system, it is facing shortage of resources and suffering from operational problems. The sustainability of irrigated agriculture is threatened due to...

An improved delivery system for bladder irrigation.

Science.gov (United States)

Moslemi, Mohammad K; Rajaei, Mojtaba

2010-10-05

Occasionally, urologists may see patients requiring temporary bladder irrigation at hospitals without stocks of specialist irrigation apparatus. One option is to transfer the patient to a urology ward, but often there are outstanding medical issues that require continued specialist input. Here, we describe an improved system for delivering temporary bladder irrigation by utilizing readily available components and the novel modification of a sphygmomanometer blub. This option is good for bladder irrigation in patients with moderate or severe gross hematuria due to various causes. In this prospective study from March 2007 to April 2009, we used our new system in eligible cases. In this system, an irrigant bag with 1 L of normal saline was suspended 80 cm above the indwelled 3-way Foley catheter, and its drainage tube was inserted into the irrigant port of the catheter. To increase the flow rate of the irrigant system, we inserted a traditional sphygmomanometer bulb at the top of the irrigant bag. This closed system was used for continuous bladder irrigation (CBI) in patients who underwent open prostatectomy, transurethral resection of the prostate (TURP), or transurethral resection of the bladder (TURB). This high-pressure system is also used for irrigation during cystourethroscopy, internal urethrotomy, and transurethral lithotripsy. Our 831 eligible cases were divided into two groups: group 1 were endourologic cases and group 2 were open prostatectomy, TURP, and TURB cases. The maximum and average flow rates were evaluated. The efficacy of our new system was compared prospectively with the previous traditional system used in 545 cases. In group 1, we had clear vision at the time of endourologic procedures. The success rate of this system was 99.5%. In group 2, the incidence of clot retention decreased two fold in comparison to traditional gravity-dependent bladder flow system. These changes were statistically significant (P = 0.001). We did not observe any adverse

Review of root canal irrigant delivery techniques and devices

Directory of Open Access Journals (Sweden)

Yeon-Jee Yoo

2011-05-01

Full Text Available Introduction Eliminating the residual debris and bacteria in the root canal system is one of the main purposes of the endodontic treatment. However, the complexity on the anatomy of the root canal system makes it difficult to eliminate the bacterial biofilm existing along the root canal surface and necrotic pulp tissue by mechanical instrumentation and chemical irrigation. Recently, more effective irrigant delivery systems for root canal irrigation have been developed. The purpose of this review was to present an overview of root canal irrigant delivery techniques and devices available in endodontics. Review The contents of this paper include as follows; - syringe-needle irrigation, manual dynamic irrigation, brushes - sonic and ultrasonic irrigation, passive ultrasonic irrigation, rotary brush, RinsEndo, EndoVac, Laser Conclusion Though technological advances during the last decade have brought to fruition new agitation devices that rely on various mechanisms, there are few evidence based study to correlate the clinical efficacy of these devices with improved outcomes except syringe irrigation with needle and ultrasonic irrigation. The clinicians should try their best efforts to deliver antimicrobial and tissue solvent solutions in predictable volumes safely to working length.

Size and stochasticity in irrigated social-ecological systems

Science.gov (United States)

Puy, Arnald; Muneepeerakul, Rachata; Balbo, Andrea L.

2017-03-01

This paper presents a systematic study of the relation between the size of irrigation systems and the management of uncertainty. We specifically focus on studying, through a stylized theoretical model, how stochasticity in water availability and taxation interacts with the stochastic behavior of the population within irrigation systems. Our results indicate the existence of two key population thresholds for the sustainability of any irrigation system: or the critical population size required to keep the irrigation system operative, and N* or the population threshold at which the incentive to work inside the irrigation system equals the incentives to work elsewhere. Crossing irretrievably leads to system collapse. N* is the population level with a sub-optimal per capita payoff towards which irrigation systems tend to gravitate. When subjected to strong stochasticity in water availability or taxation, irrigation systems might suffer sharp population drops and irreversibly disintegrate into a system collapse, via a mechanism we dub ‘collapse trap’. Our conceptual study establishes the basis for further work aiming at appraising the dynamics between size and stochasticity in irrigation systems, whose understanding is key for devising mitigation and adaptation measures to ensure their sustainability in the face of increasing and inevitable uncertainty.

Assessing the Efficacy of the SWAT Auto-Irrigation Function to Simulate Irrigation, Evapotranspiration, and Crop Response to Management Strategies of the Texas High Plains

Directory of Open Access Journals (Sweden)

Yong Chen

2017-07-01

Full Text Available In the semi-arid Texas High Plains, the underlying Ogallala Aquifer is experiencing continuing decline due to long-term pumping for irrigation with limited recharge. Accurate simulation of irrigation and other associated water balance components are critical for meaningful evaluation of the effects of irrigation management strategies. Modelers often employ auto-irrigation functions within models such as the Soil and Water Assessment Tool (SWAT. However, some studies have raised concerns as to whether the function is able to adequately simulate representative irrigation practices. In this study, observations of climate, irrigation, evapotranspiration (ET, leaf area index (LAI, and crop yield derived from an irrigated lysimeter field at the USDA-ARS Conservation and Production Research Laboratory at Bushland, Texas were used to evaluate the efficacy of the SWAT auto-irrigation functions. Results indicated good agreement between simulated and observed daily ET during both model calibration (2001–2005 and validation (2006–2010 periods for the baseline scenario (Nash-Sutcliffe efficiency; NSE ≥ 0.80. The auto-irrigation scenarios resulted in reasonable ET simulations under all the thresholds of soil water deficit (SWD triggers as indicated by NSE values > 0.5. However, the auto-irrigation function did not adequately represent field practices, due to the continuation of irrigation after crop maturity and excessive irrigation when SWD triggers were less than the static irrigation amount.

76 FR 1386 - Safety Zone; Centennial of Naval Aviation Kickoff, San Diego Bay, San Diego, CA

Science.gov (United States)

2011-01-10

...-AA00 Safety Zone; Centennial of Naval Aviation Kickoff, San Diego Bay, San Diego, CA AGENCY: Coast... zone on the navigable waters of San Diego Bay in San Diego, CA in support of the Centennial of Naval... February 12, 2010, the Centennial of Naval Aviation Kickoff will take place in San Diego Bay. In support of...

Sensing technologies for precision irrigation

CERN Document Server

Ćulibrk, Dubravko; Minic, Vladan; Alonso Fernandez, Marta; Alvarez Osuna, Javier; Crnojevic, Vladimir

2014-01-01

This brief provides an overview of state-of-the-art sensing technologies relevant to the problem of precision irrigation, an emerging field within the domain of precision agriculture. Applications of wireless sensor networks, satellite data and geographic information systems in the domain are covered. This brief presents the basic concepts of the technologies and emphasizes the practical aspects that enable the implementation of intelligent irrigation systems. The authors target a broad audience interested in this theme and organize the content in five chapters, each concerned with a specific technology needed to address the problem of optimal crop irrigation. Professionals and researchers will find the text a thorough survey with practical applications.

Intervention processes and irrigation institutions : sustainability of farmer managed irrigation systems in Nepal

OpenAIRE

Pant, D.R.

2000-01-01

With the support from various donors, His Majesty's Government of Nepal has implemented support programmes with a view to transform water availability, improve production, and increase the institutional capabilities of farmers to develop and sustain efficient, fair and reliable irrigation management practices in irrigation systems in Nepal. In this respect, this study aimed to understand the social, administrative and political processes involved in the social and institutional chang...

Untangling the effects of shallow groundwater and deficit irrigation on irrigation water productivity in arid region: New conceptual model.

Science.gov (United States)

Xue, Jingyuan; Huo, Zailin; Wang, Fengxin; Kang, Shaozhong; Huang, Guanhua

2018-04-01

Water scarcity and salt stress are two main limitations for agricultural production. Groundwater evapotranspiration (ET g ) with upward salt movement plays an important role in crop water use and water productivity in arid regions, and it can compensate the impact of deficit irrigation on crop production. Thus, comprehensive impacts of shallow groundwater and deficit irrigation on crop water use results in an improvement of irrigation water productivity (IWP). However, it is difficult to quantify the effects of groundwater and deficit irrigation on IWP. In this study, we built an IWP evaluation model coupled with a water and salt balance model and a crop yield estimation model. As a valuable tool of IWP simulation, the calibrated model was used to investigate the coupling response of sunflower IWP to irrigation water depths (IWDs), groundwater table depth (GTDs) and groundwater salinities (GSs). A total of 210 scenarios were run in which five irrigation water depths (IWDs) and seven groundwater table depths (GTDs) and six groundwater salinities (GSs) were used. Results indicate that increasing GS clearly increases the negative effect on a crop's actual evapotranspiration (ET a ) as salt accumulation in root zone. When GS is low (0.5-1g/L), increasing GTD produces more positive effect than negative effect. In regard to relatively high GS (2-5g/L), the negative effect of shallow-saline groundwater reaches a maximum at 2m GTD. Additionally, the salt concentration in the root zone maximizes its value at 2.0m GTD. In most cases, increasing GTD and GS reduces the benefits of irrigation water and IWP. The IWP increases with decreasing irrigation water. Overall, in arid regions, capillary rise of shallow groundwater can compensate for the lack of irrigation water and improve IWP. By improving irrigation schedules and taking advantages of shallow saline groundwater, we can obtain higher IWP. Copyright © 2017 Elsevier B.V. All rights reserved.

San Marino.

Science.gov (United States)

1985-02-01

San Marino, an independent republic located in north central Italy, in 1983 had a population of 22,206 growing at an annual rate of .9%. The literacy rate is 97% and the infant mortality rate is 9.6/1000. The terrain is mountainous and the climate is moderate. According to local tradition, San Marino was founded by a Christian stonecutter in the 4th century A.D. as a refuge against religious persecution. Its recorded history began in the 9th century, and it has survived assaults on its independence by the papacy, the Malatesta lords of Rimini, Cesare Borgia, Napoleon, and Mussolini. An 1862 treaty with the newly formed Kingdom of Italy has been periodically renewed and amended. The present government is an alliance between the socialists and communists. San Marino has had its own statutes and governmental institutions since the 11th century. Legislative authority at present is vested in a 60-member unicameral parliament. Executive authority is exercised by the 11-member Congress of State, the members of which head the various administrative departments of the goverment. The posts are divided among the parties which form the coalition government. Judicial authority is partly exercised by Italian magistrates in civil and criminal cases. San Marino's policies are tied to Italy's and political organizations and labor unions active in Italy are also active in San Marino. Since World War II, there has been intense rivalry between 2 political coalitions, the Popular Alliance composed of the Christian Democratic Party and the Independent Social Democratic Party, and the Liberty Committee, coalition of the Communist Party and the Socialist Party. San Marino's gross domestic product was $137 million and its per capita income was $6290 in 1980. The principal economic activities are farming and livestock raising, along with some light manufacturing. Foreign transactions are dominated by tourism. The government derives most of its revenue from the sale of postage stamps to

San Francisco District Laboratory (SAN)

Data.gov (United States)

Federal Laboratory Consortium — Program CapabilitiesFood Analysis SAN-DO Laboratory has an expert in elemental analysis who frequently performs field inspections of materials. A recently acquired...

Irrigation and avifaunal change in coastal Northwest Mexico: has irrigated habit attracted threatened migratory species?

Science.gov (United States)

Grason, Emily; Navarro-Sigüenza, Adolfo G.

2015-01-01

Irrigation in desert ecosystems can either reduce or increase species diversity. Groundwater pumping often lowers water tables and reduces natural wetlands, whereas canal irrigation often creates mesic habitat, resulting in great increases in avian diversity from irrigation. Here we compare a dataset of potential natural vegetation to recent datasets from areal and satellite imagery to show that 60% of the land in the coastal plain of southern Sonora and northern Sinaloa lying below 200 m elevation has been converted by irrigation to more mesic habitats. We then use the record of bird specimens in the world’s museums from this same region of Mexico to examine the avian community before and after the development of extensive irrigation. In general these museum records show an increase in the abundance and diversity of breeding birds associated with mesic habitats. Although thorn forest birds have likely decreased in total numbers, most are common enough in the remaining thorn forest that collection records did not indicate their probable decline. Four migrants having most of their breeding ranges in the US or Canada, Yellow-billed Cuckoo, Cliff Swallow, Bell’s Vireo, and Orchard Oriole, apparently have increased dramatically as breeders in irrigated habitats of NW Mexico. Because these species have decreased or even largely disappeared as breeding birds in parts of the US or Canada, further research should assess whether their increases in new mesic habitats of NW Mexico are linked to their declines as breeding birds in Canada and the US For Bell’s Vireo recent specimens from Sinaloa suggest its new breeding population in NW Mexico may be composed partly of the endangered Least Bell’s Vireo. PMID:26312181

ASPECTS OF DRIP IRRIGATION ON SLOPES

Directory of Open Access Journals (Sweden)

Oprea Radu

2010-01-01

Full Text Available Nowadays, water and its supply raise problems of strategic importance, of great complexity, being considered one of the keys to sustainable human development. Drip irrigation consists in the slow and controlled administration of water in the area of the root system of the plants for the purposes of fulfilling their physiological needs and is considered to be one of the variants of localized irrigation. Water is distributed in a uniform and slow manner, drop by drop, in a quantity and with a frequency that depend on the needs of the plant, thanks to the exact regulation of the water flow rate and pressure, as well as to the activation of the irrigation based on the information recorded by the tensiometer with regard to soil humidity. This method enables the exact dosage of the water quantity necessary in the various evolution stages of the plant, thus eliminating losses. By applying the irrigation with 5 liters of water per linear meter, at a 7 days interval, in the month of august, for a vine cultivated on a slope, in layers covered with black film and irrigated via dropping, soil humidity immediately after irrigation reaches its highest level, but within the limits of active humidity, on the line of the irrigation band. Three days later, the water content of the soil in the layer is relatively uniform, and, after this interval, it is higher in the points situated at the basis of the film. This technology of cultivation on slopes favors the accumulation, in the soil, of the water resulted from heavy rains and reduces soil losses as a result of erosion.

improving of irrigation management: a learning based approach

African Journals Online (AJOL)

p2333147

Irrigation farms are small businesses and like any other business, the managers or ... human factors and constraints that impact on the adoption of irrigation ... Informal interaction with other irrigation farmers and social networks played a ...

Saline water irrigation for crop production

Energy Technology Data Exchange (ETDEWEB)

Khan, A R [Directorate of Water Management Research, Indian Council of Agricultural Research (ICAR), Walmi Complex, P.O. - Phulwari Sharif, Patna (India); [Abdus Salam International Centre for Theoretical Physics, Trieste (Italy); Singh, S S; Singh, S R [Directorate of Water Management Research, Indian Council of Agricultural Research (ICAR), Walmi Complex, P.O. - Phulwari Sharif, Patna (India)

2001-05-01

Salinity is one of agriculture's most complex production problems. Excessive salts from irrigation water or high water tables can severely limit crop production. Years of saline water irrigation on poorly drained soils can eventually make economic crop production impossible. About 10% of all land are affected by salinity problems. They occur in every continent in different proportions, more frequently in arid and semi-arid areas. This paper discusses a range of problems related to use of saline water for crop irrigation.

Saline water irrigation for crop production

International Nuclear Information System (INIS)

Khan, A.R.; Singh, S.S.; Singh, S.R.

2001-05-01

Salinity is one of agriculture's most complex production problems. Excessive salts from irrigation water or high water tables can severely limit crop production. Years of saline water irrigation on poorly drained soils can eventually make economic crop production impossible. About 10% of all land are affected by salinity problems. They occur in every continent in different proportions, more frequently in arid and semi-arid areas. This paper discusses a range of problems related to use of saline water for crop irrigation

Evaluation of the Effect of Different Irrigation Levels of Drip Irrigation (Tape on Yield and Yield Components of Corn

Directory of Open Access Journals (Sweden)

mohammad karimi

2016-02-01

Full Text Available Introduction: One of the serious problems in the further development of maize cultivation is increasing irrigation efficiency. Using conventional irrigation causes a shortage of water resources to increase the acreage of the crop. With regard to the development of maize cultivation, agronomic and executable methods must be studied to reduce water consumption. Using drip irrigation system is most suitable for row crops. Hamedi et al. (2005 compared drip (tape and surface irrigation systems on yield of maize in different levels of water requirement and indicated that drip irrigation increases the amount of yield to 2015 kg/ha and water use efficiency to 3 time. Kohi et al. (2005 investigated the effects of deficit irrigation use of drip (tape irrigation on water use efficiency on maize in planting of one and two rows. The results showed that maximum water use efficiency related to crop density, water requirement and planting pattern 85000, 125% and two rows, respectively with 1.46 kg/m3. Jafari and Ashrafi (2011 studied the effects of irrigation levels, plant density and planting pattern in drip irrigation (tape on corn. The results showed that the amount of irrigation water and crop density on the level of 1% and their interactions and method of planting were significant at the 5 and 10% on water use efficiency, respectively. The yield was measured under different levels of irrigation, crop density and method of planting and the difference was significant on the level of 1%. Lamm et al. (1995 studied water requirement of maize in field with silt loam texture under sub drip irrigation and reported that water use reduced to 75%; but yield of maize remained at maximum amount of 12.5 t/ha. The objective of this study was to evaluate the drip (tape irrigation method for corn production practices in the Qazvin province in Iran. Materials and Methods: In this study, yield and yield components of corn (SC 704 were investigated under different levels of

Orígenes del control de los proyectos de obras públicas por la Academia de San Fernando (1768-1777

Directory of Open Access Journals (Sweden)

José Enrique García Melero

1998-01-01

Full Text Available Trata sobre los orígenes de la censura de obras públicas en España por la Academia madrileña entre los años 1768 y 1777. Se estudian a través de la documentación hallada en su Archivo y la bibliografía paralela complementaria. Se hallan en una serie de representaciones de los académicos al Rey Carlos III, fechadas en los años 1768 y 1777, sobre la actividad gremial. Entonces se criticaba el empleo del estilo barroco por los gremios. La crítica se centró, sobre todo, en el retablo. En su realización participaban tanto los maestros gremiales como los arquitectos, escultores y pintores académicos. En este artículo se destaca la influencia indirecta de la Academia de San Carlos de Valencia en las reales órdenes de 1777. Con ellas se cumplió el ideal político de centralización de las obras públicas en la Corte, tan del agrado de los reyes españoles de la Ilustración.This article treats about the origins ofthe censure ofpublic works in Spain done by the Madrilenian Academy from 1786 to 1777. The studies done in this article are based on the documentation found in the own Academy's Archive and in other complementary sources. We can find these origins in a serie ofrequests made by the academics to the king Carlos III and that are dated between the years 1768 and 1777, about the guild activity. By this time it was criticised the use of the Baroque style by the guilds. The critic was basically focusedin the retablo. Its realization not only was a task of the guild masters but also architects, painters and sculptors take part. In this work we point out the indirect influence ofthe San Carlos Academy, from Valencia, in the roya! orders made in 1777.

Introduction: Panda or Hydra? The untold stories of drip irrigation

NARCIS (Netherlands)

Kuper, M.; Venot, J.P.; Zwarteveen, M.; Venot, J.P.; Kuper, M.; Zwarteveen, M.

2017-01-01

Irrigated areas in the world are witnessing a transformation from open canal systems to more ‘modern’ irrigation methods such as drip irrigation that convey water through closed pipe systems. Initially associated with hi-tech irrigated agriculture, drip irrigation is now being used by a wide range

[Ecological risks of reclaimed water irrigation: a review].

Science.gov (United States)

Chen, Wei-Ping; Zhang, Wei-Ling; Pan, Neng; Jiao, Wen-Tao

2012-12-01

Wastewater reclamation and reuse have become an important approach to alleviate the water crisis in China because of its social, economic and ecological benefits. The irrigation on urban green space and farmland is the primary utilization of reclaimed water, which has been practiced world widely. To understand the risk of reclaimed water irrigation, we summarized and reviewed the publications associated with typical pollutants in reclaimed water including salts, nitrogen, heavy metals, emerging pollutants and pathogens, systematically analyzed the ecological risk posed by reclaimed water irrigation regarding plant growth, groundwater quality and public health. Studies showed that salt and salt ions were the major risk sources of reclaimed water irrigation, spreading disease was another potential risk of using reclaimed water, and emerging pollutants was the hot topic in researches of ecological risk. Based on overseas experiences, risk control measures on reclaimed water irrigation in urban green space and farmland were proposed. Five recommendations were given to promote the safe use of reclaimed water irrigation including (1) strengthen long-term in situ monitoring, (2) promote the modeling studies, (3) build up the connections of reclaimed water quality, irrigation management and ecological risk, (4) evaluate the soil bearing capacity of reclaimed water irrigation, (5) and establish risk management system of reclaimed water reuse.

Maps of the Bonsall area of the San Luis Rey River valley, San Diego County, California, showing geology, hydrology, and ground-water quality

Science.gov (United States)

Izbicki, John A.

1985-01-01

In November 1984, 84 wells and 1 spring in the Bonsall area of the San Luis Rey River valley were inventoried by U.S. Geological Survey personnel. Depth to water in 38 wells ranged from 1.3 to 38 ft and 23 wells had depths to water less than 10 feet. Dissolved solids concentration of water from 29 wells and 1 spring sampled in autumn 1983 and spring 1984 ranged from 574 to 2,370 mgs/L. Groundwater with a dissolved solids concentration less than 1,000 mgs/L was generally restricted to the eastern part of the aquifer. The total volume of alluvial fill in the Bonsall area is 113,000 acre-feet; the amount of groundwater storage available in the alluvial aquifer is 18,000 acre-feet. The alluvial aquifer is, in part, surrounded and underlain by colluvium and weathered crystalline rock that add some additional groundwater storage capacity to the system. Data in this report are presented on five maps showing well locations , thickness of alluvial fill, water level contours in November 1983 and hydrographs of selected wells, groundwater quality in spring 1960 and graphs showing changes in dissolved solids concentrations of water from selected wells with time, and groundwater quality in spring 1984. This report is part of a larger cooperative project between the Rainbow Municipal Irrigation District and the U.S. Geological Survey. The purpose of the larger project is to develop an appropriate groundwater management plan for the Bonsall area of the San Luis Rey River valley. (USGS)

Ocean-Atmosphere Interactions Modulate Irrigation's Climate Impacts

Science.gov (United States)

Krakauer, Nir Y.; Puma, Michael J.; Cook, Benjamin I.; Gentine, Pierre; Nazarenko, Larissa

2016-01-01

Numerous studies have focused on the local and regional climate effects of irrigated agriculture and other land cover and land use change (LCLUC) phenomena, but there are few studies on the role of ocean- atmosphere interaction in modulating irrigation climate impacts. Here, we compare simulations with and without interactive sea surface temperatures of the equilibrium effect on climate of contemporary (year 2000) irrigation geographic extent and intensity. We find that ocean-atmosphere interaction does impact the magnitude of global-mean and spatially varying climate impacts, greatly increasing their global reach. Local climate effects in the irrigated regions remain broadly similar, while non-local effects, particularly over the oceans, tend to be larger. The interaction amplifies irrigation-driven standing wave patterns in the tropics and mid-latitudes in our simulations, approximately doubling the global-mean amplitude of surface temperature changes due to irrigation. The fractions of global area experiencing significant annual-mean surface air temperature and precipitation change also approximately double with ocean-atmosphere interaction. Subject to confirmation with other models, these findings imply that LCLUC is an important contributor to climate change even in remote areas such as the Southern Ocean, and that attribution studies should include interactive oceans and need to consider LCLUC, including irrigation, as a truly global forcing that affects climate and the water cycle over ocean as well as land areas.

Mapping Irrigation Potential in the Upper East Region of Ghana

Science.gov (United States)

Akomeah, E.; Odai, S. N.; Annor, F. O.; Adjei, K. A.; Barry, B.

2009-04-01

The Upper East Region together with the other two regions in Northern Ghana (Upper West and Northern Region) is seen as the locus of perennial food deficit (GPRS, 2003). Despite, the provision of over 200 small scale dams and various mechanisms aimed at poverty alleviation, the region is still plagued with poverty and yearly food shortages. To achieve food security and alleviate poverty in the region however, modernization of agriculture through irrigation is deemed inevitable. While it is true that considerable potential still exists for future expansion of irrigation, it cannot be refuted that water is becoming scarcer in the regions where the need for irrigation is most important, hence mapping the irrigation potential of the region will be the first step toward ensuring sound planning and sustainability of the irrigation developments. In this study, an attempt has been made to map out the irrigation potential of the Upper East Region. The river basin approach was used in assessing the irrigation potential. The catchments drained by The White Volta river, Red volta river, River Sissili and River Kulpawn were considered in the assessment. The irrigation potential for the sub basins was computed by combining information on gross irrigation water requirements for the selected cash crops, area of soil suitable for irrigation and available water resources. The capacity of 80%, 70%, 60% and 50% time of exceedance flow of the available surface water resources in the respective sub basins was estimated. The area that can be irrigated with this flow was computed with selected cropping pattern. Combining the results of the potential irrigable areas and the land use map of the respective sub basins, an irrigation potential map has been generated showing potential sites in the upper east region that can be brought under irrigation. Keywords: Irrigation potential, irrigation water requirement, land evaluation, dependable flow

Irrigation ponds: Possibility and potentials for the treatment of drainage water from paddy fields in Zhanghe Irrigation System

Institute of Scientific and Technical Information of China (English)

DONG Bin; MAO Zhi; BROWN Larry; CHEN XiuHong; PENG LiYuan; WANG JianZhang

2009-01-01

Excessive application of fertilizers and pesticides as well as discharge of undecontaminated and un-recycled waste of livestock and poultry into farmland has caused serious non-point source pollution (NSP) of farmland in China.With the traditional mode of irrigation and drainage in rice-based irrigation systems, the pollution of farmland drainage water has become more and more serious.Traditional ir-rigation and drainage systems only focus on issues concerning water quantity, i.e.the capacity of irri-gation in drought and drainage in waterlogging period, yet have no requirement on water quality im-provement, how to clean the water quality of farmland drainage through remodeling the existing irriga-tion and drainage systems has a very important realistic meaning.Pond is an important irrigation facil-ity in rice-based irrigation systems in southern China, which has the functions of not only a storage of water from canals but also collections of surface runoffs and farmland drainage for recycling use.Such water storage features of pond provide the possibility and potential capacity for drainage water treat-ment by managing such features as treatment basins as the growth of aquatic plants as well as living of fishes, batrachia and microorganisms in pond forms a soil-plant-microorganism ecological system.To explore the potential capacity of pond for drainage water nutrient reduction, the Zhanghe Irrigation System of Hubei, a typical "melon-on-the-vine" system in southern China is selected as the research site.The results of pond survey and field experiments demonstrate that plenty of ponds are suitable for collecting and cleaning paddy field drainage, and the ponds are favorable in reducing N, P nutrients in the drainage water.Other issues, e.g.how to maximize such capacity and what strategies should be sought to make existing treatment basins hydraulically more efficient, are also discussed.

Irrigation ponds:Possibility and potentials for the treatment of drainage water from paddy fields in Zhanghe Irrigation System

Institute of Scientific and Technical Information of China (English)

BROWN; Larry

2009-01-01

Excessive application of fertilizers and pesticides as well as discharge of undecontaminated and unrecycled waste of livestock and poultry into farmland has caused serious non-point source pollution (NSP) of farmland in China. With the traditional mode of irrigation and drainage in rice-based irrigation systems, the pollution of farmland drainage water has become more and more serious. Traditional irrigation and drainage systems only focus on issues concerning water quantity, i.e. the capacity of irrigation in drought and drainage in waterlogging period, yet have no requirement on water quality improvement. how to clean the water quality of farmland drainage through remodeling the existing irrigation and drainage systems has a very important realistic meaning. Pond is an important irrigation facility in rice-based irrigation systems in southern China, which has the functions of not only a storage of water from canals but also collections of surface runoffs and farmland drainage for recycling use. Such water storage features of pond provide the possibility and potential capacity for drainage water treatment by managing such features as treatment basins as the growth of aquatic plants as well as living of fishes, batrachia and microorganisms in pond forms a soil-plant-microorganism ecological system. To explore the potential capacity of pond for drainage water nutrient reduction, the Zhanghe Irrigation System of Hubei, a typical "melon-on-the-vine" system in southern China is selected as the research site. The results of pond survey and field experiments demonstrate that plenty of ponds are suitable for collecting and cleaning paddy field drainage, and the ponds are favorable in reducing N, P nutrients in the drainage water. Other issues, e.g. how to maximize such capacity and what strategies should be sought to make existing treatment basins hydraulically more efficient, are also discussed.

Sustainable irrigation in fruit trees

Directory of Open Access Journals (Sweden)

Cristos Xiloyannis

2010-09-01

Full Text Available Water management in fruit growing, particularly in areas with high water deficit, low rainfall and limited availability of water for irrigation should aid to save water by: i the choice of high efficiency irrigation methods and their correct management; ii the proper choice of the specie, cultivar and rootstock to optimise plant water use; iii the proper choice of the architecture of the canopy and it’s correct management in order to improve water use efficiency; iv the application of regulated deficit irrigation at growth stages less sensitive to water deficit; v strengthening the role of technical assistance for a rapid transfer of knowledge to the growers on the sustainable use of water in fruit growing.

Sustainable irrigation in fruit trees

Directory of Open Access Journals (Sweden)

Cristos Xiloyannis

Full Text Available Water management in fruit growing, particularly in areas with high water deficit, low rainfall and limited availability of water for irrigation should aid to save water by: i the choice of high efficiency irrigation methods and their correct management; ii the proper choice of the specie, cultivar and rootstock to optimise plant water use; iii the proper choice of the architecture of the canopy and it’s correct management in order to improve water use efficiency; iv the application of regulated deficit irrigation at growth stages less sensitive to water deficit; v strengthening the role of technical assistance for a rapid transfer of knowledge to the growers on the sustainable use of water in fruit growing.

Root Zone Sensors for Irrigation Management in Intensive Agriculture

Directory of Open Access Journals (Sweden)

Jochen Hemming

2009-04-01

Full Text Available Crop irrigation uses more than 70% of the world’s water, and thus, improving irrigation efficiency is decisive to sustain the food demand from a fast-growing world population. This objective may be accomplished by cultivating more water-efficient crop species and/or through the application of efficient irrigation systems, which includes the implementation of a suitable method for precise scheduling. At the farm level, irrigation is generally scheduled based on the grower’s experience or on the determination of soil water balance (weather-based method. An alternative approach entails the measurement of soil water status. Expensive and sophisticated root zone sensors (RZS, such as neutron probes, are available for the use of soil and plant scientists, while cheap and practical devices are needed for irrigation management in commercial crops. The paper illustrates the main features of RZS’ (for both soil moisture and salinity marketed for the irrigation industry and discusses how such sensors may be integrated in a wireless network for computer-controlled irrigation and used for innovative irrigation strategies, such as deficit or dual-water irrigation. The paper also consider the main results of recent or current research works conducted by the authors in Tuscany (Italy on the irrigation management of container-grown ornamental plants, which is an important agricultural sector in Italy.

Rice Photosynthetic Productivity and PSII Photochemistry under Nonflooded Irrigation

Directory of Open Access Journals (Sweden)

Haibing He

2014-01-01

Full Text Available Nonflooded irrigation is an important water-saving rice cultivation technology, but little is known on its photosynthetic mechanism. The aims of this work were to investigate photosynthetic characteristics of rice during grain filling stage under three nonflooded irrigation treatments: furrow irrigation with plastic mulching (FIM, furrow irrigation with nonmulching (FIN, and drip irrigation with plastic mulching (DI. Compared with the conventional flooding (CF treatment, those grown in the nonflooded irrigation treatments showed lower net photosynthetic rate (PN, lower maximum quantum yield (Fv/Fm, and lower effective quantum yield of PSII photochemistry (ΦPSII. And the poor photosynthetic characteristics in the nonflooded irrigation treatments were mainly attributed to the low total nitrogen content (TNC. Under non-flooded irrigation, the PN, Fv/Fm, and ΦPSII significantly decreased with a reduction in the soil water potential, but these parameters were rapidly recovered in the DI and FIM treatments when supplementary irrigation was applied. Moreover, The DI treatment always had higher photosynthetic productivity than the FIM and FIN treatments. Grain yield, matter translocation, and dry matter post-anthesis (DMPA were the highest in the CF treatment, followed by the DI, FIM, and FIN treatments in turn. In conclusion, increasing nitrogen content in leaf of rice plants could be a key factor to improve photosynthetic capacity in nonflooded irrigation.

Irrigation Capability Evaluation of Illushi Floodplain, Edo State, Nigeria

Directory of Open Access Journals (Sweden)

A.S. Umweni

2014-06-01

Full Text Available Many irrigation projects, especially in the developing tropical regions, are embarked upon without any land capability assessment, resulting in avoidable and undesirable ecological consequences. The aim of this study is to assess the irrigation capability potentials of the soils of a rice growing Illushi/Ega community in Edo State of Nigeria. Soils of Illushi/Ega (200 ha were studied to establish their irrigation capabilities. Water samples were collected from the rivers within and near the sites at the proposed points of intake structures and analyzed for salinity (ECw, permeability (SAR and ion toxicity [Chlorine (Cl and Boron (B]. Gravity irrigation suitability assessment was carried out following the guidelines of the United States Bureau for Land Reclamation (USBR, 1953 and FAO (1979. Results showed that about 5.5 % of the land was non-irrigable, 11.5 % was marginally irrigable, 30.5% was moderately irrigable and 52.5 % highly irrigable.Thus about 83 % of the total land area was found to be irrigable. The results of analyses of irrigation water [ECw, SAR and Cl and B (ion toxicity problems in water sources were 0.1 – 0.7 dS m-1, 1.2 – 1.7, 0.6 – 1.8 cmol kg-1 and 0.5 – 0.7 mg kg-1] also show that there is no indication of salinity or ion toxicity problem.

Contrainte supplémentaire de potentiel dans une simulation monte carlo inverse pour l'étude de l'electrolyte aqueux LICL-6H2O à l'etat vitreux.

OpenAIRE

HABCHI, Mohammed

2015-01-01

L’électrolyte aqueux de type LICI-6H2O est étudie a l’état vitreux (120k) . Ce système présente la proprette de former un verre en passant par l’état liquide métastable surfondu quand la température diminue . La méthode de simulation utilisée dette de monte Carlo inverse (RMC) de l'anglais reverse monte Carlo celle-ci présent l’intérêt de pouvoir être appliquée sans que les interaction interatomiques et intermoléculaires soient spécifies .

Grower demand for sensor-controlled irrigation

Science.gov (United States)

Lichtenberg, Erik; Majsztrik, John; Saavoss, Monica

2015-01-01

Water scarcity is likely to increase in the coming years, making improvements in irrigation efficiency increasingly important. An emerging technology that promises to increase irrigation efficiency substantially is a wireless irrigation sensor network that uploads sensor data into irrigation management software, creating an integrated system that allows real-time monitoring and control of moisture status that has been shown in experimental settings to reduce irrigation costs, lower plant loss rates, shorten production times, decrease pesticide application, and increase yield, quality, and profit. We use an original survey to investigate likely initial acceptance, ceiling adoption rates, and profitability of this new sensor network technology in the nursery and greenhouse industry. We find that adoption rates for a base system and demand for expansion components are decreasing in price, as expected. The price elasticity of the probability of adoption suggests that sensor networks are likely to diffuse at a rate somewhat greater than that of drip irrigation. Adoption rates for a base system and demand for expansion components are increasing in specialization in ornamental production: growers earning greater shares of revenue from greenhouse and nursery operations are willing to pay more for a base system and are willing to purchase larger numbers of expansion components at any given price. We estimate that growers who are willing to purchase a sensor network expect investment in this technology to generate significant profit, consistent with findings from experimental studies.

Adaptive Markov Chain Monte Carlo

KAUST Repository

Jadoon, Khan

2016-08-08

A substantial interpretation of electromagnetic induction (EMI) measurements requires quantifying optimal model parameters and uncertainty of a nonlinear inverse problem. For this purpose, an adaptive Bayesian Markov chain Monte Carlo (MCMC) algorithm is used to assess multi-orientation and multi-offset EMI measurements in an agriculture field with non-saline and saline soil. In the MCMC simulations, posterior distribution was computed using Bayes rule. The electromagnetic forward model based on the full solution of Maxwell\\'s equations was used to simulate the apparent electrical conductivity measured with the configurations of EMI instrument, the CMD mini-Explorer. The model parameters and uncertainty for the three-layered earth model are investigated by using synthetic data. Our results show that in the scenario of non-saline soil, the parameters of layer thickness are not well estimated as compared to layers electrical conductivity because layer thicknesses in the model exhibits a low sensitivity to the EMI measurements, and is hence difficult to resolve. Application of the proposed MCMC based inversion to the field measurements in a drip irrigation system demonstrate that the parameters of the model can be well estimated for the saline soil as compared to the non-saline soil, and provide useful insight about parameter uncertainty for the assessment of the model outputs.

76 FR 9709 - Water Quality Challenges in the San Francisco Bay/Sacramento-San Joaquin Delta Estuary

Science.gov (United States)

2011-02-22

... Water Quality Challenges in the San Francisco Bay/Sacramento-San Joaquin Delta Estuary AGENCY... the San Francisco Bay/ Sacramento-San Joaquin Delta Estuary (Bay Delta Estuary) in California. EPA is... programs to address recent significant declines in multiple aquatic species in the Bay Delta Estuary. EPA...

Reducing microbial contamination on wastewater-irrigated lettuce by cessation of irrigation before harvesting

DEFF Research Database (Denmark)

Keraita, Bernard; Konradsen, Flemming; Drechsel, Pay

2007-01-01

OBJECTIVE: To assess the effectiveness of cessation of irrigation before harvesting in reducing microbial contamination of lettuce irrigated with wastewater in urban vegetable farming in Ghana. METHODS: Assessment was done under actual field conditions with urban vegetable farmers in Ghana. Trials...... were arranged in completely randomized block design and done both in the dry and wet seasons. Seven hundred and twenty-six lettuce samples and 36 water samples were analysed for thermotolerant coliforms and helminth eggs. RESULTS: On average, 0.65 log units for indicator thermotolerant coliforms and 0.......4 helminth eggs per 100 g of lettuce were removed on each non-irrigated day from lettuce in the dry season. This corresponded to a daily loss of 1.4 tonnes/ha of fresh weight of lettuce. As an input for exposure analysis to make risk estimates, the decay coefficient, k, for thermotolerant coliforms was 0...

Drip Irrigation for Commercial Vegetable and Fruit Production

OpenAIRE

Maughn, Tiffany; Allen, Niel; Drost, Dan

2017-01-01

Drip irrigation is a highly efficient irrigation method well suited to many fruit and vegetable row crops. Drip tubing or tape discharges water to the soil through emitters positioned close to the plant. The drip tubing can be placed uncovered on the soil surface, under plastic mulch, buried in the soil, or suspended above the ground (e.g., on a trellis system). Water application rate is relatively low and irrigations are usually frequent. Properly designed and maintained drip-irrigation syst...

Practical salinity management for leachate irrigation to poplar trees.

Science.gov (United States)

Smesrud, Jason K; Duvendack, George D; Obereiner, James M; Jordahl, James L; Madison, Mark F

2012-01-01

Landfill leachate can be beneficially reused for irrigation of fiber crops with appropriate attention to nutrient and salinity management. The Riverbend Landfill in Western Oregon has been effectively practicing irrigation of landfill leachate to poplar trees since 1993. Over that time, the site has been adaptively managed to control salinity impacts to the tree crop while beneficially utilizing the applied water and nutrients during each growing season. Representative leachate irrigation water has ranged in concentration of total dissolved solids from 777 to 6,940 mg/L, chloride from 180 to 1,760 mg/L and boron from 3.2 to 7.3 mg/L. Annual leachate irrigation applications have also ranged between 102 and 812 mm/yr. Important conclusions from this site have included: 1) Appropriate tree clone selection and tree stand spacing, thinning, and harvest rotations are critical to maintaining a productive tree stand that is resilient and resistant to salt stress. The most effective combinations have included clones DN-34, OP-367, 184-411, 49-177, and 15-29 planted at spacing of 3.7-m x 1.8-m to 3.7-m x 3.7-m; 2) Leaf tissue boron levels are closely correlated to soil boron levels and can be managed with leaching. When leaf tissue boron levels exceed 200 to 250 mg/kg, signs of salt stress may emerge and should be monitored closely; 3) Salinity from leachate irrigation can be managed to sustain a healthy tree crop by controlling mass loading rates and providing appropriate irrigation blending if necessary. Providing freshwater irrigation following each leachate irrigation and targeting freshwater irrigation as 30 percent of total irrigation water applied has successfully controlled salt impacts to vegetation; and 4) Drip irrigation generally requires more careful attention to long-term soil salinity management than spray irrigation. Moving drip irrigation tubes periodically to prevent the formation of highly saline zones within the soil profile is important. In this paper, a

Irrigation Requirement Estimation Using Vegetation Indices and Inverse Biophysical Modeling

Science.gov (United States)

Bounoua, Lahouari; Imhoff, Marc L.; Franks, Shannon

2010-01-01

We explore an inverse biophysical modeling process forced by satellite and climatological data to quantify irrigation requirements in semi-arid agricultural areas. We constrain the carbon and water cycles modeled under both equilibrium, balance between vegetation and climate, and non-equilibrium, water added through irrigation. We postulate that the degree to which irrigated dry lands vary from equilibrium climate conditions is related to the amount of irrigation. The amount of water required over and above precipitation is considered as an irrigation requirement. For July, results show that spray irrigation resulted in an additional amount of water of 1.3 mm per occurrence with a frequency of 24.6 hours. In contrast, the drip irrigation required only 0.6 mm every 45.6 hours or 46% of that simulated by the spray irrigation. The modeled estimates account for 87% of the total reported irrigation water use, when soil salinity is not important and 66% in saline lands.

Computer-based irrigation scheduling for cotton crop

International Nuclear Information System (INIS)

Laghari, K.Q.; Memon, H.M.

2008-01-01

In this study a real time irrigation schedule for cotton crop has been tested using mehran model, a computer-based DDS (Decision Support System). The irrigation schedule was set on selected MAD (Management Allowable Depletion) and the current root depth position. The total 451 mm irrigation water applied to the crop field. The seasonal computed crop ET (Evapotranspiration) was estimated 421.32 mm and actual (ET/sub ca/) observed was 413 mm. The model over-estimated seasonal ET by only 1.94. WUE (Water Use Efficiency) for seed-cotton achieved 6.59 Kg (ha mm)/sup -1/. The statistical analysis (R/sup 2/=0.96, ARE%=2.00, T-1.17 and F=550.57) showed good performance of the model in simulated and observed ET values. The designed Mehran model is designed quite versatile for irrigation scheduling and can be successfully used as irrigation DSS tool for various crop types. (author)

Hydrology of the middle San Pedro area, southeastern Arizona

Science.gov (United States)

Cordova, Jeffrey T.; Dickinson, Jesse; Beisner, Kimberly R.; Hopkins, Candice B.; Kennedy, Jeffrey R.; Pool, Donald R.; Glenn, Edward P.; Nagler, Pamela L.; Thomas, Blakemore E.

2015-05-05

In the middle San Pedro Watershed in southeastern Arizona, groundwater is the primary source of water supply for municipal, domestic, industrial, and agricultural use. The watershed comprises two smaller subareas, the Benson subarea and the Narrows-Redington subarea. Early 21st century projections for heavy population growth in the watershed have not yet become a reality, but increased groundwater withdrawals could have undesired consequences - such as decreased base flow to the San Pedro River, and groundwater-level declines - that would lead to the need to deepen existing wells. This report describes the hydrology, hydrochemistry, water quality, and development of a groundwater budget for the middle San Pedro Watershed, focusing primarily on the elements of groundwater movement that could be most useful for the development of a groundwater modelPrecipitation data from Tombstone, Arizona, and base flow at the stream-gaging station on the San Pedro River at Charleston both show relatively dry periods during the 1960s through the mid-1980s and in the mid-1990s to 2009, and wetter periods from the mid-1980s through the mid-1990s. Water levels in four out of five wells near the mountain fronts show cyclical patterns of recharge, with rates of recharge greatest in the early 1980s through the mid-1990s. Three wells near the San Pedro River recorded their lowest levels during the 1950s to the mid-1960s. The water-level record from one well, completed in the confined part of the coarse-grained lower basin fill, showed a decline of approximately 21 meters.Annual flow of the San Pedro River, measured at the Charleston and Redington gages, has decreased since the 1940s. The median annual streamflow and base flow at the gaging station on the river near Tombstone has decreased by 50 percent between the periods 1968–1986 and 1997–2009. Estimates of streamflow infiltration along the San Pedro River during 1914–2009 have decreased 44 percent, with the largest decreases in

[Continent colostomy and colon irrigation].

Science.gov (United States)

Kostov, D; Temelkov, T; Kiriazov, E; Ivanov, K; Ignatov, V; Kobakov, G

2000-01-01

The authors have studied a functional activity of a continent colostomy at 20 patients, undergone an abdomeno-perineal extirpation of rectum and carried out periodic colonirrigations, during a period of 6 months. A conus type, closed irrigating system has been used. The degree of an incontinency at patients has been compared before and after the beginning of the colonirrigations. The irrigating procedures have reduced spontaneous defications at patients during a week 28 times and have improved the quality of life significantly. The application of colostomy bags has been restricted in 8 (40%) patients. An intraluminal ultrasonographic investigation has been done at 12 (60%) patients at the end of 6 month irrigating period. No changes of the ultrasonographic image of the precolostomic segment of colon has been observed.

Modelling human agency in ancient irrigation

NARCIS (Netherlands)

Ertsen, M.W.

2011-01-01

Human activity is key in understanding ancient irrigation systems. Results of short term actions build up over time, affecting civilizations on larger temporal and spatial scales. Irrigation systems, with their many entities, social and physical, their many interactions within a changing environment

33 CFR 165.776 - Security Zone; Coast Guard Base San Juan, San Juan Harbor, Puerto Rico

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Security Zone; Coast Guard Base San Juan, San Juan Harbor, Puerto Rico 165.776 Section 165.776 Navigation and Navigable Waters COAST... Guard District § 165.776 Security Zone; Coast Guard Base San Juan, San Juan Harbor, Puerto Rico (a...

Irrigated agriculture with limited water supply:Tools for understanding and managing irrigation and crop water use efficiencies

Science.gov (United States)

Water availability for irrigated agriculture is declining in both China and the United States due to increased use for power generation, municipalities, industries and environmental protection. Persistent droughts have exacerbated the situation, leading to increases in irrigated area as farmers atte...

Scheduling irrigation for jujube ( Ziziphus jujuba Mill. ) | Zhang ...

African Journals Online (AJOL)

This study was performed to select suitable indicator for scheduling the irrigation of jujube (Ziziphus jujuba Mill.) grown in the Loess Plateau. The relationships between plant-based indicators and soil matrix potential as well as meteorological factors of jujube under deficit irrigation compared with well irrigation were ...

Fluid regimens for colostomy irrigation: a systematic review.

Science.gov (United States)

Lizarondo, Lucylynn; Aye Gyi, Aye; Schultz, Tim

2008-09-01

Background  Various techniques for managing faecal evacuation have been proposed; however, colostomy irrigation is favoured as it leads to better patient outcomes. Alternative fluid regimens for colostomy irrigation have been suggested to achieve effective evacuation. Aim  The objective of this review was to summarise the best available evidence on the most effective fluid regimen for colostomy irrigation. Search strategy  Trials were identified by electronic searches of CINAHL, PubMed, MEDLINE, Current Contents, the Cochrane Library and EMBASE. Unpublished articles and references lists from included studies were also searched. Selection criteria  Randomised controlled trials and before-and-after studies investigating any fluid regimen for colostomy irrigation were eligible for inclusion. Outcomes measured included fluid inflow time, total wash-out time, haemodynamic changes during irrigation, cramps, leakage episodes, quality of life and level of satisfaction. Data collection and analysis  Trial selection, quality appraisal and data extraction were carried out independently by two reviewers. Differences in opinion were resolved by discussion. Main results  The systematic literature search strategy identified two cross-over trials that compared water with another fluid regimen. Owing to the differences in irrigating solutions used, the results were not pooled for analysis. Both the polyethylene glycol electrolyte solution and glyceryl trinitrate performed significantly better than water. Conclusion  There is some evidence to support the effectiveness of fluid regimens other than water, such as polyethylene glycol electrolyte and glyceryl trinitrate, for colostomy irrigation. Further well-designed clinical trials are required to establish solid evidence on the effectiveness of other irrigating solutions that might enhance colonic irrigation. © 2008 The Authors. Journal Compilation © Blackwell Publishing Asia Pty Ltd.

Willingness to Pay Additional Water Rate and Irrigation Knowledge of Farmers in Dinar Karakuyu Irrigation Areas in Turkey

Directory of Open Access Journals (Sweden)

Mevlüt Gül

2017-08-01

Full Text Available Water which has become commodity product which is an important product today. Turkey is not a water rich country. In this study, agricultural enterprises in the field of Irrigation Project in Dinar Karakuyu which was implemented in 1992 by DSI. The study analysed which factors affect the willingness to pay additional irrigation water rate with the help of logit model and the irrigation knowledge of farmers was determined by Likert scale. Dinar Karakuyu irrigation network has begun to lose the function in the region. It was supposed 100% irrigation rate but decreased by approximately 9% today. In this context, DSI (General Directorate of State Hydraulic Works plans to rehabilitation work in the same area. The main material of this study was data obtained from 67 agricultural enterprises through a survey covered by the Irrigation Rehabilitation Project in the province of Afyonkarahisar Karakuyu Dinar. The data was gathered with the help of questionnaires which were answered by farmers in Karakuyu Dinar region. The results indicated that 74.6% of farmers were willingness to pay additional water charge. The data were statistically analysed with the use of the logit model. The model results show that agricultural income, farmers’ educational level, computer ownership, attendance of agricultural training activities, family size and agricultural experience were positive factors affect farmers’ willingness to pay additional water fee.

Armenia - Irrigation Infrastructure

Data.gov (United States)

Millennium Challenge Corporation — This study evaluates irrigation infrastructure rehabilitation in Armenia. The study separately examines the impacts of tertiary canals and other large infrastructure...

Comparison of Manual and Automatic Irrigation of Pot Experiments

DEFF Research Database (Denmark)

Haahr, Vagner

1975-01-01

An air-lift principle for transport of water was adapted for automatic irrigation of experimental pots originally constructed for manual irrigation by the weighing method. The two irrigation techniques were compared in an experiment with increasing amounts of nitrogen fertilizer to spring barley....... Productions of grain and straw and chemical composition were almost the same after the two irrigation methods, and it was concluded that the laborious manual watering could be replaced by automatic irrigation. Comparison of the yield from individual plants in the pots showed a large difference between centre...... plants and border plants independent of irrigation principle. The increase in yield per pot with increasing N fertilization was at the highest N level caused only by an increase in yield of the border plants....

Effect of Irrigation with Reclaimed Water on Fruit Characteristics and Photosynthesis of Olive Trees under Two Irrigation Systems

Directory of Open Access Journals (Sweden)

N. Ashrafi

2016-02-01

Full Text Available Introduction: Olive (Olea europaea L. trees are mainly cultivated in the Mediterranean area and are grown for their oil or processed as table olives. Despite the fact that olive is known to be resistant to drought conditions due to its anatomical, physiological, and biochemical adaptations to drought stress, reports indicate that the olive can be adversely affected by drought stress, which has a negative effect on the growth of olive trees. In the absence of adequate supplies of water, the demand for water can be met by using improved irrigation methods or by using reclaimed water (RW. Reports have shown that recycled water has been used successfully for irrigating olive orchards with no negative effects on plant growth.Attention has been paid to reclaimed water as one of the most significant available water resources used in agriculture around large cities in arid and semi-arid regions. On the other hand, irrigation efficiency is low and does not meet the demands of farmers.In order to investigate the possibility of irrigating olive orchards with subsurface leakage irrigation (SLI in application of reclaimed water, an experiment was carried out with the aim of investigating the effect of reclaimed water on photosynthetic indices and morphological properties of olive fruit. Materials and Methods: Research was conducted using a split-plot experimental design with two factors (irrigation system and water quality on the campus of Isfahan University of Technology in Isfahan, Iran, on a sandy-clay soil with a pH of 7.5 and electrical conductivity (EC of 2.48 dSm-1.PVC leaky tubes were used for the SLI system. The SLI system was installed 40 cm from the crown of each tree at a depth of 30 - 40 cm.At the end of the experiment fruit yield, weight per fruit, volume, length and firmness were calculated. A portable gas exchange system (Li-6400., LICOR, Lincoln, NE, USA was used to measure the net rate photosynthesis (A, the internal partial pressure CO2

Irrigation development and management in Ghana: Prospects and ...

African Journals Online (AJOL)

... existing schemes. It is envisaged that irrigation will be seen in its right perspective as a multidisciplinary activity to ensure the success of schemes. There is the need for running a postgraduate programme in irrigation at the KNUST to enhance the nations efforts at developing and managing irrigation projects successfully.

Irrigation Depletions 1928-1989 : 1990 Level of Irrigation, Snake Yakima and Deschutes River Basins.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administation; A.G. Crook Company

1993-07-01

The vast amount of irrigation in relation to the available water and extensive system of reservoirs located in the Snake River Basin above Brownlee reservoir precludes this area from using methods such as Blaney-Criddle for estimating irrigation depletions. Also the hydrology, irrigation growth patterns, and water supply problems are unique and complex. Therefore regulation studies were utilized to reflect the net effect on streamflow of the changes in irrigated acreage in terms of corresponding changes in storage regulation and in the amount of water depleted and diverted from and returned to the river system. The regulation study for 1990 conditions was conducted by the Idaho Department of Water Resources. The end product of the basin simulation is 61 years of regulated flows at various points in the river system that are based on 1990 conditions. Data used by the Idaho Department of Water Resources is presented in this section and includes natural gains to the river system and diversions from the river system based on a 1990 level of development and operation criteria. Additional information can be obtained for an Idaho Department of Water Resources Open-File Report ``Stream Flows in the Snake River Basin 1989 Conditions of Use and Management`` dated June 1991. Similar considerations apply to the Yakima and Deschutes river basins.

Enhanced Preliminary Assessment Report: Presidio of San Francisco Military Reservation, San Francisco, California

Science.gov (United States)

1989-11-01

CAD981415656 Filmore Steiner Bay San Francisco 24 PG&E Gas Plant SanFran 502-IG CAD981415714 Bay North Point Buchanan Laguna 25 PG&E Gas Plant SanFran 502-1H...76-ioV /5,JO /0.7 /,230 PSF Water PSF, Main U.N. Lagunda Honda Analvte Plant Clearwell Reservoir Plaza Reservoi- Chlordane inetab. ə.2 ə.2 (1.2 ə.2

Predicting deep percolation with eddy covariance under mulch drip irrigation

Science.gov (United States)

Ming, Guanghui; Tian, Fuqiang; Hu, Hongchang

2016-04-01

Water is essential for the agricultural development and ecological sustainability of the arid and semi-arid oasis with rare precipitation input and high evaporation demand. Deep percolation (DP) defined as excess irrigation water percolating below the plant root zone will reduce irrigation water use efficiency (WUE). But the DP was often ignored in mulch drip irrigation (MDI) which has reached the area of 1.6 million hectares in Xinjiang, the northwest of China. In this study DP experiments were conducted at an agricultural experiment station located within an irrigation district in the Tarim River Basin for four cotton growing periods. First it was detected the irrigation water infiltrated into the soil layers below 100cm and the groundwater level responded to the irrigation events well. Then DP below 100cm soil layers was calculated using the soil water balance method with the aid of eddy covariance (with the energy balance closure of 0.72). The negative DP (groundwater contribution to the crop-water use through capillary rising) at the seedling and harvesting stages can reach 77mm and has a good negative correlation with the groundwater level and positive correlation with potential evaporation. During the drip irrigation stage approximately 45% of the irrigation became DP and resulted in the low irrigation WUE of 0.6. The DP can be 164mm to 270mm per year which was positive linearly correlated to irrigation depth and negative linear correlated to irrigation interval. It is better to establish the irrigation schedule with small irrigation depth and given frequently to reduce deep percolation and meet crop needs.

Automated Irrigation System for Greenhouse Monitoring

Science.gov (United States)

Sivagami, A.; Hareeshvare, U.; Maheshwar, S.; Venkatachalapathy, V. S. K.

2018-06-01

The continuous requirement for the food needs the rapid improvement in food production technology. The economy of food production is mainly dependent on agriculture and the weather conditions, which are isotropic and thus we are not able to utilize the whole agricultural resources. The main reason is the deficiency of rainfall and paucity in land reservoir water. The continuous withdrawal water from the ground reduces the water level resulting in most of the land to come under the arid. In the field of cultivation, use of appropriate method of irrigation plays a vital role. Drip irrigation is a renowned methodology which is very economical and proficient. When the conventional drip irrigation system is followed, the farmer has to tag along the irrigation timetable, which is different for diverse crops. The current work makes the drip irrigation system an automated one, thereby the farmer doesn't want to follow any timetable since the sensor senses the soil moisture content and based on it supplies the water. Moreover the practice of economical sensors and the simple circuitry makes this project as an inexpensive product, which can be bought even by an underprivileged farmer. The current project is best suited for places where water is limited and has to be used in limited quantity.

Automated Irrigation System for Greenhouse Monitoring

Science.gov (United States)

Sivagami, A.; Hareeshvare, U.; Maheshwar, S.; Venkatachalapathy, V. S. K.

2018-03-01

The continuous requirement for the food needs the rapid improvement in food production technology. The economy of food production is mainly dependent on agriculture and the weather conditions, which are isotropic and thus we are not able to utilize the whole agricultural resources. The main reason is the deficiency of rainfall and paucity in land reservoir water. The continuous withdrawal water from the ground reduces the water level resulting in most of the land to come under the arid. In the field of cultivation, use of appropriate method of irrigation plays a vital role. Drip irrigation is a renowned methodology which is very economical and proficient. When the conventional drip irrigation system is followed, the farmer has to tag along the irrigation timetable, which is different for diverse crops. The current work makes the drip irrigation system an automated one, thereby the farmer doesn't want to follow any timetable since the sensor senses the soil moisture content and based on it supplies the water. Moreover the practice of economical sensors and the simple circuitry makes this project as an inexpensive product, which can be bought even by an underprivileged farmer. The current project is best suited for places where water is limited and has to be used in limited quantity.

Gain-P: A new strategy to increase furrow irrigation efficiency

International Nuclear Information System (INIS)

Schmitz, G.H.; Wohling, T.; Paly, M. D.; Schutze, N.

2007-01-01

The new methodology GAIN-P combines Genetic Algorithms, Artificial Intelligence techniques and rigorous Process modeling for substantially improving irrigation efficiency. The new strategy simultaneously identifies optimal values of both scheduling and irrigation parameters for an entire growing season and can be applied to irrigation systems with adequate or deficit water supply. In this contribution, GAIN-P is applied to furrow irrigation tackling the more difficult subject of the more effective deficit irrigation. A physically -based hydrodynamic irrigation model is iteratively coupled with a 2D subsurface flow model for generating a database containing all realistically feasible scenarios of water application in furrow irrigation. It is used for training a problem-adapted artificial neural network based on self-organized maps, which in turn portrays the inverse solution of the hydrodynamic furrow irrigation model and thus enormously speeds up the overall performance of the complete optimization tool. Global optimization with genetic algorithm finds the schedule with maximum crop yield for the given water volume. The impact of different irrigation schedules on crop yield is calculated by the coupled furrow irrigation model which also simulates soil evaporation, precipitation and root water uptake by the plants over the whole growing seasons, as well as crop growth and yield. First results with the new optimization strategy show that GAIN-P has a high potential to increase irrigation efficiency. (author)

Updates on Water Use of Pistachio Orchards Grown in the San Joaquin Valley of California on Saline Soils

Science.gov (United States)

Zaccaria, Daniele; Marino, Giulia; Whiting, Michael; Sanden, Blake; Ferguson, Louise; Lampinen, Bruce; Kent, Eric; Snyder, Richard; Grattan, Stephen; Little, Cayle

2017-04-01

Pistachio acreage is rapidly expanding in California thanks to its economic profitability and capacity to grow and produce in salt-affected soils. Our team at University of California is updating information on actual water use (ET) of mature pistachio orchards grown on saline soils under micro-irrigation methods. Actual Evapotranspiration (ETa) and Crop Coefficients (Ka) were determined for the 2015 and 2016 crop seasons on four pistachio orchards grown in the San Joaquin Valley (SJV) on grounds with increasing levels of soil-water salinity, using the residual of energy balance method with a combination of eddy covariance and surface renewal equipment. Tree canopy cover, light interception, and plant water status across the orchards were also measured and evaluated. Our preliminary results show that salinity strongly affects the tree water use, resulting in 10-30% less ET for medium to high salt-affected soils. Salinity also showed a strong effect on tree water status and light interception, as suggested by values of the Midday Stem Water Potential (ΨSWP) around 10 to 15-bar lower in salt-affected than in the control orchard, and by the intercepted Photosynthetic Active Radiation (PAR) decreasing from 75% in the control orchard to 25% in the severely salt affected grounds. The crop coefficient values we observed in this study are lower than those commonly used for irrigation scheduling in the SJV, suggesting that pistachio growers could better tailor irrigation management to the actual site-specific orchard conditions (e.g. canopy features and soil-water salinity) if they are provided updated information. Improved irrigation practices could likely lead to significant water savings and thus improve the resource-efficiency and competitiveness of pistachio production in the SJV. Keywords: Pistacia vera L., salinity, stem water potential, surface renewal, canopy cover.

Memory of irrigation effects on hydroclimate and its modeling challenge

Science.gov (United States)

Chen, Fei; Xu, Xiaoyu; Barlage, Michael; Rasmussen, Roy; Shen, Shuanghe; Miao, Shiguang; Zhou, Guangsheng

2018-06-01

Irrigation modifies land-surface water and energy budgets, and also influences weather and climate. However, current earth-system models, used for weather prediction and climate projection, are still in their infancy stage to consider irrigation effects. This study used long-term data collected from two contrasting (irrigated and rainfed) nearby maize-soybean rotation fields, to study the effects of irrigation memory on local hydroclimate. For a 12 year average, irrigation decreases summer surface-air temperature by less than 1 °C and increases surface humidity by 0.52 g kg‑1. The irrigation cooling effect is more pronounced and longer lasting for maize than for soybean. Irrigation reduces maximum, minimum, and averaged temperature over maize by more than 0.5 °C for the first six days after irrigation, but its temperature effect over soybean is mixed and negligible two or three days after irrigation. Irrigation increases near-surface humidity over maize by about 1 g kg‑1 up to ten days and increases surface humidity over soybean (~ 0.8 g kg‑1) with a similar memory. These differing effects of irrigation memory on temperature and humidity are associated with respective changes in the surface sensible and latent heat fluxes for maize and soybean. These findings highlight great need and challenges for earth-system models to realistically simulate how irrigation effects vary with crop species and with crop growth stages, and to capture complex interactions between agricultural management and water-system components (crop transpiration, precipitation, river, reservoirs, lakes, groundwater, etc.) at various spatial and temporal scales.

The Regularity of Optimal Irrigation Patterns

Science.gov (United States)

Morel, Jean-Michel; Santambrogio, Filippo

2010-02-01

A branched structure is observable in draining and irrigation systems, in electric power supply systems, and in natural objects like blood vessels, the river basins or the trees. Recent approaches of these networks derive their branched structure from an energy functional whose essential feature is to favor wide routes. Given a flow s in a river, a road, a tube or a wire, the transportation cost per unit length is supposed in these models to be proportional to s α with 0 measure is the Lebesgue density on a smooth open set and the irrigating measure is a single source. In that case we prove that all branches of optimal irrigation trees satisfy an elliptic equation and that their curvature is a bounded measure. In consequence all branching points in the network have a tangent cone made of a finite number of segments, and all other points have a tangent. An explicit counterexample disproves these regularity properties for non-Lebesgue irrigated measures.

Closed chamber globe stabilization and needle capsulorhexis using irrigation hand piece of bimanual irrigation and aspiration system

Directory of Open Access Journals (Sweden)

Rai Harminder K

2005-08-01

Full Text Available Abstract Background The prerequisites for a good capsulorhexis include a deep, well maintained anterior chamber, globe stabilization and globe manipulation. This helps to achieve a capsulorhexis of optimal size, shape and obtain the best possible position for a red glow under retroillumination. We report the use of irrigation handpiece of bimanual irrigation aspiration system to stabilize the globe, maintain a deep anterior chamber and manipulate the globe to a position of optimal red reflex during needle capsulorhexis in phacoemulsification. Methods Two side ports are made with 20 G MVR 'V' lance knife (Alcon, USA. The irrigation handpiece with irrigation on is introduced into the anterior chamber through one side port and the 26-G cystitome (made from 26-G needle is introduced through the other. The capsolurhexis is completed with the needle. Results Needle capsulorhexis with this technique was used in 30 cases of uncomplicated immature senile cataracts. 10 cases were done under peribulbar anaesthesia and 20 under topical anaesthesia. A complete capsulorhexis was achieved in all cases. Conclusion The irrigating handpiece maintains deep anterior chamber, stabilizes the globe, facilitates pupillary dilatation, and helps in maintaining the eye in the position with optimal red reflex during needle capsulorhexis. This technique is a safe and effective way to perform needle capsulorhexis.

Irrigation scheduling of spring wheat using infrared thermometry

International Nuclear Information System (INIS)

Stegman, E.C.; Soderlund, M.G.

1989-01-01

Irrigation scheduling for spring wheat requires information on different irrigation timing methods. Irrigation timing based on allowable root zone available water depletion and selected crop water stress index (CWSI) thresholds were evaluated in terms of their effect on spring wheat yield. A field study was conducted at Oakes, North Dakota in 1987 and 1988 on a Maddock sandy loam soil with two varieties of spring wheat (Marshall and Wheaton) using a split plot randomized block design. Irrigation was metered to each plot using trickle irrigation tubing. Neutron soil water measurements along with a water balance model were used to time irrigations that were based on different allowed root zone depletions. Infrared thermometer sensors (IRT) were used to measure in situ canopy temperatures and along with measured climatic information were used to time irrigations using the CWSI approach. Additionally, crop phenological stages and final grain yield were measured. The non-water-stressed baselines necessary for the CWSI differed between the two seasons but were similar to those from previous studies. The CWSI methods were feasible from the Feekes scale S4 (beginning pseudo-stem) to S11.2 (mealy ripe). Minimal yield reductions were observed using the CWSI method for thresholds less than 0.4-0.5 during this period. Minimal yield reductions were observed by maintaining the root zone allowable depletion below 50%. The grain yield-evapotranspiration (ET) relationship was linear in both years but with different slopes and intercepts. When analyzed on a relative basis to maximum ET (ETm), a single relationship fit both years’ data with a yield sensitivity factor of 1.58. Irrigations timed at CWSI = 0.5 reduced seasonal water application by 18% relative to treatments irrigated at CWSI = 0.2. (author)

Monte Carlo methods

Directory of Open Access Journals (Sweden)

Bardenet Rémi

2013-07-01

Full Text Available Bayesian inference often requires integrating some function with respect to a posterior distribution. Monte Carlo methods are sampling algorithms that allow to compute these integrals numerically when they are not analytically tractable. We review here the basic principles and the most common Monte Carlo algorithms, among which rejection sampling, importance sampling and Monte Carlo Markov chain (MCMC methods. We give intuition on the theoretical justification of the algorithms as well as practical advice, trying to relate both. We discuss the application of Monte Carlo in experimental physics, and point to landmarks in the literature for the curious reader.

A case for historic joint rupture of the San Andreas and San Jacinto faults.

Science.gov (United States)

Lozos, Julian C

2016-03-01

The San Andreas fault is considered to be the primary plate boundary fault in southern California and the most likely fault to produce a major earthquake. I use dynamic rupture modeling to show that the San Jacinto fault is capable of rupturing along with the San Andreas in a single earthquake, and interpret these results along with existing paleoseismic data and historic damage reports to suggest that this has likely occurred in the historic past. In particular, I find that paleoseismic data and historic observations for the ~M7.5 earthquake of 8 December 1812 are best explained by a rupture that begins on the San Jacinto fault and propagates onto the San Andreas fault. This precedent carries the implications that similar joint ruptures are possible in the future and that the San Jacinto fault plays a more significant role in seismic hazard in southern California than previously considered. My work also shows how physics-based modeling can be used for interpreting paleoseismic data sets and understanding prehistoric fault behavior.

A case for historic joint rupture of the San Andreas and San Jacinto faults

Science.gov (United States)

Lozos, Julian C.

2016-01-01

The San Andreas fault is considered to be the primary plate boundary fault in southern California and the most likely fault to produce a major earthquake. I use dynamic rupture modeling to show that the San Jacinto fault is capable of rupturing along with the San Andreas in a single earthquake, and interpret these results along with existing paleoseismic data and historic damage reports to suggest that this has likely occurred in the historic past. In particular, I find that paleoseismic data and historic observations for the ~M7.5 earthquake of 8 December 1812 are best explained by a rupture that begins on the San Jacinto fault and propagates onto the San Andreas fault. This precedent carries the implications that similar joint ruptures are possible in the future and that the San Jacinto fault plays a more significant role in seismic hazard in southern California than previously considered. My work also shows how physics-based modeling can be used for interpreting paleoseismic data sets and understanding prehistoric fault behavior. PMID:27034977

Estimating irrigation water use in the humid eastern United States

Science.gov (United States)

Levin, Sara B.; Zarriello, Phillip J.

2013-01-01

Accurate accounting of irrigation water use is an important part of the U.S. Geological Survey National Water-Use Information Program and the WaterSMART initiative to help maintain sustainable water resources in the Nation. Irrigation water use in the humid eastern United States is not well characterized because of inadequate reporting and wide variability associated with climate, soils, crops, and farming practices. To better understand irrigation water use in the eastern United States, two types of predictive models were developed and compared by using metered irrigation water-use data for corn, cotton, peanut, and soybean crops in Georgia and turf farms in Rhode Island. Reliable metered irrigation data were limited to these areas. The first predictive model that was developed uses logistic regression to predict the occurrence of irrigation on the basis of antecedent climate conditions. Logistic regression equations were developed for corn, cotton, peanut, and soybean crops by using weekly irrigation water-use data from 36 metered sites in Georgia in 2009 and 2010 and turf farms in Rhode Island from 2000 to 2004. For the weeks when irrigation was predicted to take place, the irrigation water-use volume was estimated by multiplying the average metered irrigation application rate by the irrigated acreage for a given crop. The second predictive model that was developed is a crop-water-demand model that uses a daily soil water balance to estimate the water needs of a crop on a given day based on climate, soil, and plant properties. Crop-water-demand models were developed independently of reported irrigation water-use practices and relied on knowledge of plant properties that are available in the literature. Both modeling approaches require accurate accounting of irrigated area and crop type to estimate total irrigation water use. Water-use estimates from both modeling methods were compared to the metered irrigation data from Rhode Island and Georgia that were used to

Is current irrigation sustainable in the United States? An integrated assessment of climate change impact on water resources and irrigated crop yields

Science.gov (United States)

Blanc, Elodie; Caron, Justin; Fant, Charles; Monier, Erwan

2017-08-01

While climate change impacts on crop yields has been extensively studied, estimating the impact of water shortages on irrigated crop yields is challenging because the water resources management system is complex. To investigate this issue, we integrate a crop yield reduction module and a water resources model into the MIT Integrated Global System Modeling framework, an integrated assessment model linking a global economic model to an Earth system model. We assess the effects of climate and socioeconomic changes on water availability for irrigation in the U.S. as well as subsequent impacts on crop yields by 2050, while accounting for climate change projection uncertainty. We find that climate and socioeconomic changes will increase water shortages and strongly reduce irrigated yields for specific crops (i.e., cotton and forage), or in specific regions (i.e., the Southwest) where irrigation is not sustainable. Crop modeling studies that do not represent changes in irrigation availability can thus be misleading. Yet, since the most water-stressed basins represent a relatively small share of U.S. irrigated areas, the overall reduction in U.S. crop yields is small. The response of crop yields to climate change and water stress also suggests that some level of adaptation will be feasible, like relocating croplands to regions with sustainable irrigation or switching to less irrigation intensive crops. Finally, additional simulations show that greenhouse gas (GHG) mitigation can alleviate the effect of water stress on irrigated crop yields, enough to offset the reduced CO2 fertilization effect compared to an unconstrained GHG emission scenario.

76 FR 10945 - San Luis Trust Bank, FSB, San Luis Obispo, CA; Notice of Appointment of Receiver

Science.gov (United States)

2011-02-28

... DEPARTMENT OF THE TREASURY Office of Thrift Supervision San Luis Trust Bank, FSB, San Luis Obispo, CA; Notice of Appointment of Receiver Notice is hereby given that, pursuant to the authority... appointed the Federal Deposit Insurance Corporation as sole Receiver for San Luis Trust Bank, FSB, San Luis...

Charts for Guiding Adjustments of Irrigation Interval to Actual Weather Conditions

International Nuclear Information System (INIS)

Kipkorir, E.C.

2002-01-01

Major problems in irrigation management at short time-step during the season are unreliability of rainfall and absence of guidance. By considering the climate of region, crop and soil characteristics, the irrigation method and local irrigation practices, this paper presents the concept of irrigation charts. The charts are based on soil water technique. As an example irrigation chart for a typical irrigation system located in the semi-arid area in Naivasha, Kenya is presented. The chart guides the user in adjustment of irrigation interval to the actual weather conditions throughout the growing season. It is believed that the simplicity of the chart makes it a useful tool for a better utilisation of the limited irrigation water

Irrigation water policy analysis using a business simulation game

Science.gov (United States)

Buchholz, M.; Holst, G.; Musshoff, O.

2016-10-01

Despite numerous studies on farmers' responses to changing irrigation water policies, uncertainties remain about the potential of water pricing schemes and water quotas to reduce irrigation. Thus far, policy impact analysis is predominantly based upon rational choice models that assume behavioral assumptions, such as a perfectly rational profit-maximizing decision maker. Also, econometric techniques are applied which could lack internal validity due to uncontrolled field data. Furthermore, such techniques are not capable of identifying ill-designed policies prior to their implementation. With this in mind, we apply a business simulation game for ex ante policy impact analysis of irrigation water policies at the farm level. Our approach has the potential to reveal the policy-induced behavioral change of the participants in a controlled environment. To do so, we investigate how real farmers from Germany, in an economic experiment, respond to a water pricing scheme and a water quota intending to reduce irrigation. In the business simulation game, the participants manage a "virtual" cash-crop farm for which they make crop allocation and irrigation decisions during several production periods, while facing uncertain product prices and weather conditions. The results reveal that a water quota is able to reduce mean irrigation applications, while a water pricing scheme does not have an impact, even though both policies exhibit equal income effects for the farmers. However, both policies appear to increase the variation of irrigation applications. Compared to a perfectly rational profit-maximizing decision maker, the participants apply less irrigation on average, both when irrigation is not restricted and when a water pricing scheme applies. Moreover, the participants' risk attitude affects the irrigation decisions.

76 FR 22809 - Safety Zone; Bay Ferry II Maritime Security Exercise; San Francisco Bay, San Francisco, CA

Science.gov (United States)

2011-04-25

... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 [Docket No. USCG-2011-0196] RIN 1625-AA00 Safety Zone; Bay Ferry II Maritime Security Exercise; San Francisco Bay, San Francisco, CA AGENCY... Security Exercise; San Francisco Bay, San Francisco, CA. (a) Location. The limits of this safety zone...

Chemical colostomy irrigation with glyceryl trinitrate solution.

Science.gov (United States)

O'Bichere, A; Bossom, C; Gangoli, S; Green, C; Phillips, R K

2001-09-01

Colostomy irrigation may improve patient quality of life, but is time consuming. This study tests the hypothesis that irrigation with glyceryl trinitrate solution, by inducing gastrointestinal smooth muscle relaxation, may accelerate expulsion of stool by passive emptying, thereby reducing irrigation time. Fifteen colostomy irrigators(with more than 3 years' experience) performed washout with tap water compared with water containing 0.025 mg/kg glyceryl trinitrate. Fluid inflow time, total washout time, and hemodynamic changes occurring during glyceryl trinitrate irrigation were documented by an independent observer. Subjects recorded episodes of fecal leakage and overall satisfaction on a visual analog scale. Cramps, headaches, and whether or not a stoma bag was used were expressed as a percentage of number of irrigations. Comparison of fluid inflow time, total washout time, leakage, and satisfaction was by Wilcoxon's signed-rank test and headaches, cramps, and stoma bag use was by McNemar's test. Pulse rate (paired t-test), systolic and diastolic blood pressures (Wilcoxon's test) at 20 and 240 minutes after washout with glyceryl trinitrate solution were compared with baseline. Fifteen patients (9 female), with a mean age of 53 (31-73) years, provided 30 sessions (15 with water and 15 with glyceryl trinitrate). Medians (interquartile ranges) for water vs. glyceryl trinitrate were fluid inflow time 7 (4-10) vs. 4, (3-5; P = 0.001); total washout time 40 (30-55) vs. 21, (15-24; P colostomy irrigation time compared with the generally recommended tap water. Patients suffer fewer leakages and are highly satisfied, but side effects are potential drawbacks. Other colonoplegic agent solutions should now be evaluated.

Prospective controlled trial comparing colostomy irrigation with "spontaneous-action" method.

Science.gov (United States)

Williams, N S; Johnston, D

1980-07-12

Thirty randomly selected patients with permanent colostomies entered a prospective controlled trial comparing colostomy irrigation with spontaneous action. Each patient was interviewed and examined before irrigation was begun and again after the technique had been used for three months. Each then reverted to spontaneous action for a further three months and was then reassessed. Eight patients abandoned irrigation and 22 (73%) adhered to the protocol. Irrigation caused no mishaps or complications. The mean time spent managing the stoma was 45 +/- SEM 9 min/24 hours during spontaneous action and 53 +/- 9 min/24 hours during irrigation. This difference was not significant. The numbers of bowel actions weekly were 13 +/ SEM 2 during spontaneous action and 6 +/- 1 during irrigation (p Irrigation reduced odour and flatus in 20 patients and enabled 12 out of 18 to stop using drugs and seven to discard their appliance. Irrigation also improved the social life of 18 patients and the working conditions of eight out of 14. These finding show that some patients may not be suitable for irrigation but that for many it is better than the conventional British method of colostomy management. With modern apparatus the technique is safe.

Experimental study of faecal continence and colostomy irrigation.

Science.gov (United States)

O'Bichere, A; Sibbons, P; Doré, C; Green, C; Phillips, R K

2000-07-01

Colostomy irrigation is a useful method of achieving faecal continence in selected conditions, but remains largely underutilized because it is time consuming. This study investigated the effect of modifying irrigation technique (route, infusion regimen and pharmacological manipulation) on colonic emptying time in a porcine model. An end-colostomy and caecostomy were fashioned in six pigs. Twenty markers were introduced into the caecum immediately before colonic irrigation. Irrigation route (antegrade or retrograde), infusion regimen (tap water, polyethylene glycol (PEG), 1.5 per cent glycine) and pharmacological agent (glyceryl trinitrate (GTN) 0.25 mg/kg, diltiazem 3.9 mg/kg, bisacodyl 0.25 mg/kg) were assigned to each animal at random. Colonic transit was assessed by quantifying cumulative expelled markers (CEM) and stool every hour for 12 h. Mean CEM at 6 h for bisacodyl, GTN and diltiazem were 18.17, 12.17 and zero respectively; all pairwise differences in means were significant (P irrigation. PEG and glycine enhance emptying similar to bisacodyl and GTN solution. These findings show promise for improved faecal continence by colostomy irrigation and may justify construction of a Malone conduit at the time of colostomy in selected patients who wish to irrigate. Presented in part to the British Society of Gastroenterology in Glasgow, UK, March 1999, and published in abstract form as Gut 1999; 44(Suppl 1): A135

Design of a TOF-SANS instrument for the proposed long wavelength target station at the spallation neutron source

International Nuclear Information System (INIS)

Thiyagarajan, P.; Littrell, K.; Seeger, P.A.

2001-01-01

We have designed a versatile high-throughput SANS instrument [Broad Range Intense Multipurpose SANS (BRIMS)] for the proposed Long Wavelength Target Station at the SNS by using acceptance diagrams and the Los Alamos NISP Monte Carlo simulation package. This instrument has been fully optimized to take advantage of the 10 Hz source frequency (broad wavelength bandwidth) and the cold neutron spectrum from a tall coupled solid methane moderator (12 cm x 20 cm). BRIMS has been designed to produce data in a Q range spanning from 0.0025 to 0.7 A -1 in a single measurement by simultaneously using neutrons with wavelengths ranging from 1 to 14.5 A in a time of flight mode. A supermirror guide and bender assembly is employed to separate and redirect the useful portion of the neutron spectrum with λ>1 A, by 2.3deg away from the direct beam containing high energy neutrons and γ rays. The effects of various collimation choices on count rate, resolution and Q min have been characterized using spherical particle and delta function scatterers. The overall performance of BRIMS has been compared with that of the best existing reactor-based SANS instrument D22 at ILL. (author)

Distillation irrigation: a low-energy process for coupling water purification and drip irrigation

Science.gov (United States)

Constantz, J.

1989-01-01

A method is proposed for combining solar distillation and drip irrigation to simultaneously desalinize water and apply this water to row crops. In this paper, the basic method is illustrated by a simple device constructed primarily of sheets of plastic, which uses solar energy to distill impaired water and apply the distillate to a widely spaced row crop. To predict the performance of the proposed device, an empirical equation for distillate production, dp, is developed from reported solar still production rates, and a modified Jensen-Haise equation is used to calculate the potential evapotranspiration, et, for a row crop. Monthly values for et and dp are calculated by using a generalized row crop at five locations in the Western United States. Calculated et values range from 1 to 22 cm month-1 and calculated dp values range from 2 to 11 cm month-1, depending on the location, the month, and the crop average. When the sum of dp plus precipitation, dp + P, is compared to et for the case of 50% distillation irrigation system coverage, the results indicate that the crop's et is matched by dp + P, at the cooler locations only. However, when the system coverage is increased to 66%, the crop's et is matched by dp + P even at the hottest location. Potential advantages of distillation irrigation include the ability: (a) to convert impaired water resources to water containing no salts or sediments; and (b) to efficiently and automatically irrigate crops at a rate that is controlled primarily by radiation intensities. The anticipated disadvantages of distillation irrigation include: (a) the high costs of a system, due to the large amounts of sheeting required, the short lifetime of the sheeting, and the physically cumbersome nature of a system; (b) the need for a widely spaced crop to reduce shading of the system by the crop; and (c) the production of a concentrated brine or precipitate, requiring proper off-site disposal. ?? 1989.

Matching soil salinization and cropping systems in communally managed irrigation schemes

Science.gov (United States)

Malota, Mphatso; Mchenga, Joshua

2018-03-01

Occurrence of soil salinization in irrigation schemes can be a good indicator to introduce high salt tolerant crops in irrigation schemes. This study assessed the level of soil salinization in a communally managed 233 ha Nkhate irrigation scheme in the Lower Shire Valley region of Malawi. Soil samples were collected within the 0-0.4 m soil depth from eight randomly selected irrigation blocks. Irrigation water samples were also collected from five randomly selected locations along the Nkhate River which supplies irrigation water to the scheme. Salinity of both the soil and the irrigation water samples was determined using an electrical conductivity (EC) meter. Analysis of the results indicated that even for very low salinity tolerant crops (ECi water was suitable for irrigation purposes. However, root-zone soil salinity profiles depicted that leaching of salts was not adequate and that the leaching requirement for the scheme needs to be relooked and always be adhered to during irrigation operation. The study concluded that the crop system at the scheme needs to be adjusted to match with prevailing soil and irrigation water salinity levels.

Field trials show the fertilizer value of nitrogen in irrigation water

Directory of Open Access Journals (Sweden)

Mike Cahn

2017-04-01

Full Text Available Increased regulatory activity designed to protect groundwater from degradation by nitrate-nitrogen (NO3-N is focusing attention on the efficiency of agricultural use of nitrogen (N. One area drawing scrutiny is the way in which growers consider the NO3-N concentration of irrigation water when determining N fertilizer rates. Four drip-irrigated field studies were conducted in the Salinas Valley evaluating the impact of irrigation water NO3-N concentration and irrigation efficiency on the N uptake efficiency of lettuce and broccoli crops. Irrigation with water NO3-N concentrations from 2 to 45 milligrams per liter were compared with periodic fertigation of N fertilizer. The effect of irrigation efficiency was determined by comparing an efficient (110% to 120% of crop evapotranspiration, ETc and an inefficient (160% to 200% of ETc irrigation treatment. Across these trials, NO3-N from irrigation water was at least as efficiently used as fertilizer N; the uptake efficiency of irrigation water NO3-N averaged approximately 80%, and it was not affected by NO3-N concentration or irrigation efficiency.

effect of deficit irrigation on growth and yield of okro

African Journals Online (AJOL)

User

reduce the demand for irrigation water (Boland et al., 1993). Deficit irrigation is another way in which water use efficiency can be maximized for higher yields per unit of irrigation water. Stegman (1982) reported that the yield of maize, sprinkler irrigated to induce a 30 - 40 percent depletion of available water between.

Precision overhead irrigation is suitable for several Central Valley crops

Directory of Open Access Journals (Sweden)

Jeffrey P. Mitchell

2016-04-01

Full Text Available Overhead systems are the dominant irrigation technology in many parts of the world, but they are not widely used in California even though they have higher water application efficiency than furrow irrigation systems and lower labor requirements than drip systems. With water and labor perennial concerns in California, the suitability of overhead systems merits consideration. From 2008 through 2013, in studies near Five Points, California, we evaluated overhead irrigation for wheat, corn, cotton, tomato, onion and broccoli as an alternative to furrow and drip irrigation. With the exception of tomato, equal or increased yields were achieved with overhead irrigation. Many variables are involved in the choice of an irrigation system, but our results suggest that, with more research to support best management practices, overhead irrigation may be useful to a wider set of California farmers than currently use it.

INTEGRATED WATER MANAGEMENT AND DURABILITY OF LANDSCAPE OF PUBLIC IRRIGATED AREAS IN TUNISIA: CASES OF PUBLIC IRRIGATED AREAS OF CHOTT-MARIEM AND MORNAG

OpenAIRE

Abdelkarim Hamrita; Amira Boussetta; Rafael Mata Olmo; Mehdi Saqalli; Hichem Rejeb

2017-01-01

An important part of the landscape of irrigated areas in Tunisia is the result of morphology, organization and operation of agricultural policies implemented since independence, aimed at optimizing the exploitation of the best soils and natural resources, particularly water and productive crop intensification. The sustainability of the landscape of public irrigated areas has a strong bonding with the resources of irrigation water and their states of management. The scarcity of irrigation wate...

Irrigation scheduling with the neutron probe

International Nuclear Information System (INIS)

Travers, P.

1987-01-01

The operational theory of the neutron probe is briefly outlined and its application and uses discussed in relation to determination of soil compaction and irrigation scheduling. Graphic examples are given of alluvial soil moisture profiles and how this information can be used to improve trickle irrigation in vineyards. 3 refs., 7 figs

Effects of Supplemental Irrigation on Yield and Growth Indices of Three

Directory of Open Access Journals (Sweden)

M. Parsa

2012-04-01

Full Text Available In order to investigate the effects of different irrigation regimes on yield and growth indices of three chickpea cultivars, an experiment was conducted during the 2007 growing season at Mashhad (Iran. Six irrigation regimes including I1; full irrigation, I2; irrigation at branching, I3; irrigation at flowering, I4; irrigation at pod formation, I5; irrigation at seed filling stage and I6; dry farming without irrigation (main factors. Three Kabuli chickpea cultivars ILC482, Jam, Karaj 12-60-31 (sub factors in a spilt block experiment based on randomized block design with three replications. There were significant differences between supplemental irrigation levels on grain yield. The results showed that grain yield in supplemental irrigation at flowering stage was more than to supplemental irrigation at branching, podding and seed filling stages (respectively 3.3, 3.1 and 23%. Within the three cultivars, grain yield, biological yield and harvest index were highest and lowest in ILC482 and Karaj 12-60-31 cultivars respectively. The results showed that supplemental irrigation at flowering stage increased dry matter, leaf area index, crop growth rate, relative growth rate and net assimilation rate. The results showed that flowering stage in chickpea cultivars was sensitive to drought stress so, ILC482 cultivar also showed more tolerance to water stress condition.

Evaluation of potential water conservation using site-specific irrigation

Science.gov (United States)

With the advent of site-specific variable-rate irrigation (VRI) systems, irrigation can be spatially managed within sub-field-sized zones. Spatial irrigation management can optimize spatial water use efficiency and may conserve water. Spatial VRI systems are currently being managed by consultants ...

Sustainable Irrigation Development in the White Volta Sub-Basin

NARCIS (Netherlands)

Ofosu, E.A.

2011-01-01

This study on sustainable irrigation development identified growing markets for irrigated products as an important driving force behind the expansion of irrigation which has given rise to new technologies. The new technologies have spread because they gave farmers direct control over water sources.

Ring Irrigation System (RIS) design through customer preference representation

OpenAIRE

Ridwan Infandra I.Z.; Rianmora Suchada; Werawatganon Siwat

2018-01-01

In agricultural field, irrigation is one of the most interesting considerations affecting the rate of plant growth and development. Micro-irrigation as the dripping or sprinkle method is one of the irrigation types that applies the small amount of water for fulfilling the humidity requirement. The most important factors affecting the demand of water for plants are soil conditions and effect of climatic factors. With less human labour required, to improve the irrigation method from the recent ...

Stability of Adrenaline in Irrigating Solution for Intraocular Surgery.

Science.gov (United States)

Shibata, Yuuka; Kimura, Yasuhiro; Taogoshi, Takanori; Matsuo, Hiroaki; Kihira, Kenji

2016-01-01

Intraocular irrigating solution containing 1 µg/mL adrenaline is widely used during cataract surgery to maintain pupil dilation. Prepared intraocular irrigating solutions are recommended for use within 6 h. After the irrigating solution is admistered for dilution, the adrenaline may become oxidized, and this may result in a decrease in its biological activity. However, the stability of adrenaline in intraocular irrigating solution is not fully understood. The aim of this study was to evaluate the stability of adrenaline in clinically used irrigating solutions of varying pH. Six hours after mixing, the adrenaline percentages remaining were 90.6%±3.7 (pH 7.2), 91.1%±2.2 (pH 7.5), and 65.2%±2.8 (pH 8.0) of the initial concentration. One hour after mixing, the percentages remaining were 97.6%±2.0 (pH 7.2), 97.4%±2.7 (pH 7.5), and 95.6%±3.3 (pH 8.0). The degradation was especially remarkable and time dependent in the solution at pH 8.0. These results indicate that the concentration of adrenaline is decreased after preparation. Moreover, we investigated the influence of sodium bisulfite on adrenaline stability in irrigating solution. The percentage adrenaline remaining at 6 h after mixing in irrigating solution (pH 8.0) containing sodium bisulfite at 0.5 µg/mL (concentration in irrigating solution) or at 500 µg/mL (concentration in the undiluted adrenaline preparation) were 57.5 and 97.3%, respectively. Therefore, the low concentration of sodium bisulfite in the irrigating solution may be a cause of the adrenaline loss. In conclusion, intraocular irrigation solution with adrenaline should be prepared just prior to its use in surgery.

Irrigation et paludisme : un couple infernal?

Directory of Open Access Journals (Sweden)

Mergeai, G.

2016-01-01

Full Text Available Irrigation and Malaria - a Terrible Combination?. Increasing agricultural productivity is a priority in most of the developing countries and using irrigation is one of the most efficient ways of achieving this goal. Almost half a billion people in the world contract malaria every year and approximately one million die as a result. The majority of these victims are farmers or members of their families. In infected areas, malaria continues to have major negative impacts on agricultural productivity. For example, in the Equateur province of the DRC, after access to production means, fevers are considered the second biggest obstacle to the development of agricultural activities. In the Ivory Coast, a study has shown that growers suffering from malaria were about half as productive as their healthy colleagues. The disease often strikes at the start of the rainy season when work begins again in the fields. It reduces the amount of land cultivated and affects the amount of care taken with crops. Agricultural practices influence the risk of contracting malaria. Irrigation, in particular, can encourage the proliferation of vectors of the disease and make it more likely to spread. This tendency can be observed in many locations where irrigated rice production is on the increase. Paradoxically, however, an increased number of mosquitoes does not systematically result in more malaria. In Ethiopia, malaria is more prevalent close to the micro-dams sponsored by the government, whereas, in Tanzania, there is less malaria in irrigated areas. Various theories can be put forward in order to explain this paradox. In particular, increased income due to higher rice yields enables farmers to purchase insecticide-treated mosquito nets. It also allows them to eat better, which strengthens their immune systems. It also appears that the negative impact of irrigation systems is greater in areas, in which immunity levels were low in the population prior to the creation of

NUTRIENT CONTENT IN SUNFLOWERS IRRIGATED WITH OIL EXPLORATION WATER

Directory of Open Access Journals (Sweden)

ADERVAN FERNANDES SOUSA

2016-01-01

Full Text Available Irrigation using produced water, which is generated during crude oil and gas recovery and treated by the exploration industry, could be an option for irrigated agriculture in semiarid regions. To determine the viability of this option, the effects of this treated water on the nutritional status of plants should be assessed. For this purpose, we examined the nutritional changes in sunflowers after they were irrigated with oil - produced water and the effects of this water on plant biomass and seed production. The sunflower cultivar BRS 321 was grown for three crop cycles in areas irrigated with filtered produced water (FPW, reverse osmosis - treated produced water (OPW, or ground water (GW. At the end of each cycle, roots, shoots, and seeds were collected to examine their nutrient concentrations. Produced water irrigation affected nutrient accumulation in the sunflower plants. OPW irrigation promoted the accumulation of Ca, Na, N, P, and Mg. FPW irrigation favored the accumulation of Na in both roots and shoots, and biomass and seed production were negatively affected. The Na in the shoots of plants irrigated with FPW increased throughout the three crop cycles. Under controlled conditions, it is possible to reuse reverse osmosis - treated produced water in agriculture. However, more long - term research is needed to understand its cumulative effects on the chemical and biological properties of the soil and crop production.

Dealing with drought in irrigated agriculture through insurance schemes: an application to an irrigation district in Southern Spain

Energy Technology Data Exchange (ETDEWEB)

Ruiz, M.; Bielza, J.; Garrido, A.; Iglesias, A.

2015-07-01

Hydrological drought is expected to have an increasing impact on both crop and fruit yields in arid and semi-arid regions. Some existing crop insurance schemes provide coverage against water deficits in rain-fed agriculture. The Prevented Planting Program in the USA covers against drought for irrigated agriculture. However, drought insurance for irrigated agriculture is still a challenge for companies and institutions because of the complexity of the design and implementation of this type of insurance. Few studies have attempted to evaluate the risk of loss due to irrigation water scarcity using both stand-alone production functions and crop simulation models. This paper’s contributions are that it evaluates the suitability of AquaCrop for calculating drought insurance premiums for irrigated agriculture and that it discusses contract conditions and insurance design for hydrological drought risk coverage as part of a traditional insurance product, with on-field loss assessment in combination with a trigger index. This method was applied to an irrigation district in southern Spain. Our insurance premium calculation showed that it is feasible to apply this method provided that its data requirements are met, such as a large enough set of reliable small-scale yield and irrigation time series data, especially soil data, to calibrate AquaCrop. The choice of a trigger index should not be underestimated because it proved to have a decisive influence on insurance premiums and indemnities. Our discussion of the contract conditions shows that hydrological drought insurance must comply with a series of constraints in order to avoid moral hazard and basis risk. (Author)

Dealing with drought in irrigated agriculture through insurance schemes: an application to an irrigation district in Southern Spain

Directory of Open Access Journals (Sweden)

Jorge Ruiz

2015-12-01

Full Text Available Hydrological drought is expected to have an increasing impact on both crop and fruit yields in arid and semi-arid regions. Some existing crop insurance schemes provide coverage against water deficits in rain-fed agriculture. The Prevented Planting Program in the USA covers against drought for irrigated agriculture. However, drought insurance for irrigated agriculture is still a challenge for companies and institutions because of the complexity of the design and implementation of this type of insurance. Few studies have attempted to evaluate the risk of loss due to irrigation water scarcity using both stand-alone production functions and crop simulation models. This paper’s contributions are that it evaluates the suitability of AquaCrop for calculating drought insurance premiums for irrigated agriculture and that it discusses contract conditions and insurance design for hydrological drought risk coverage as part of a traditional insurance product, with on-field loss assessment in combination with a trigger index. This method was applied to an irrigation district in southern Spain. Our insurance premium calculation showed that it is feasible to apply this method provided that its data requirements are met, such as a large enough set of reliable small-scale yield and irrigation time series data, especially soil data, to calibrate AquaCrop. The choice of a trigger index should not be underestimated because it proved to have a decisive influence on insurance premiums and indemnities. Our discussion of the contract conditions shows that hydrological drought insurance must comply with a series of constraints in order to avoid moral hazard and basis risk.

Using container weights to determine irrigation needs: A simple method

Science.gov (United States)

R. Kasten Dumroese; Mark E. Montville; Jeremiah R. Pinto

2015-01-01

Proper irrigation can reduce water use, water waste, and incidence of disease. Knowing when to irrigate plants in container nurseries can be determined by weighing containers. This simple method is quantifiable, which is a benefit when more than one worker is responsible for irrigation. Irrigation is necessary when the container weighs some target as a proportion of...

A Fuzzy analytical hierarchy process approach in irrigation networks maintenance

Science.gov (United States)

Riza Permana, Angga; Rintis Hadiani, Rr.; Syafi'i

2017-11-01

Ponorogo Regency has 440 Irrigation Area with a total area of 17,950 Ha. Due to the limited budget and lack of maintenance cause decreased function on the irrigation. The aim of this study is to make an appropriate system to determine the indices weighted of the rank prioritization criteria for irrigation network maintenance using a fuzzy-based methodology. The criteria that are used such as the physical condition of irrigation networks, area of service, estimated maintenance cost, and efficiency of irrigation water distribution. 26 experts in the field of water resources in the Dinas Pekerjaan Umum were asked to fill out the questionnaire, and the result will be used as a benchmark to determine the rank of irrigation network maintenance priority. The results demonstrate that the physical condition of irrigation networks criterion (W1) = 0,279 has the greatest impact on the assessment process. The area of service (W2) = 0,270, efficiency of irrigation water distribution (W4) = 0,249, and estimated maintenance cost (W3) = 0,202 criteria rank next in effectiveness, respectively. The proposed methodology deals with uncertainty and vague data using triangular fuzzy numbers, and, moreover, it provides a comprehensive decision-making technique to assess maintenance priority on irrigation network.

Integrating Growth Stage Deficit Irrigation into a Process Based Crop Model

Science.gov (United States)

Lopez, Jose R.; Winter, Jonathan M.; Elliott, Joshua; Ruane, Alex C.; Porter, Cheryl; Hoogenboom, Gerrit

2017-01-01

Current rates of agricultural water use are unsustainable in many regions, creating an urgent need to identify improved irrigation strategies for water limited areas. Crop models can be used to quantify plant water requirements, predict the impact of water shortages on yield, and calculate water productivity (WP) to link water availability and crop yields for economic analyses. Many simulations of crop growth and development, especially in regional and global assessments, rely on automatic irrigation algorithms to estimate irrigation dates and amounts. However, these algorithms are not well suited for water limited regions because they have simplistic irrigation rules, such as a single soil-moisture based threshold, and assume unlimited water. To address this constraint, a new modeling framework to simulate agricultural production in water limited areas was developed. The framework consists of a new automatic irrigation algorithm for the simulation of growth stage based deficit irrigation under limited seasonal water availability; and optimization of growth stage specific parameters. The new automatic irrigation algorithm was used to simulate maize and soybean in Gainesville, Florida, and first used to evaluate the sensitivity of maize and soybean simulations to irrigation at different growth stages and then to test the hypothesis that water productivity calculated using simplistic irrigation rules underestimates WP. In the first experiment, the effect of irrigating at specific growth stages on yield and irrigation water use efficiency (IWUE) in maize and soybean was evaluated. In the reproductive stages, IWUE tended to be higher than in the vegetative stages (e.g. IWUE was 18% higher than the well watered treatment when irrigating only during R3 in soybean), and when rainfall events were less frequent. In the second experiment, water productivity (WP) was significantly greater with optimized irrigation schedules compared to non-optimized irrigation schedules in

The San Bernabe power substation; La subestacion San Bernabe

Energy Technology Data Exchange (ETDEWEB)

Chavez Sanudo, Andres D. [Luz y Fuerza del Centro, Mexico, D. F. (Mexico)

1997-12-31

The first planning studies that gave rise to the San Bernabe substation go back to year 1985. The main circumstance that supports this decision is the gradual restriction for electric power generation that has been suffering the Miguel Aleman Hydro System, until its complete disappearance, to give priority to the potable water supply through the Cutzamala pumping system, that feeds in an important way Mexico City and the State of Mexico. In this document the author describes the construction project of the San Bernabe Substation; mention is made of the technological experiences obtained during the construction and its geographical location is shown, as well as the one line diagram of the same [Espanol] Los primeros estudios de planeacion que dieron origen a la subestacion San Bernabe se remontan al ano de 1985. La circunstancia principal que soporta esta decision es la restriccion paulatina para generar energia que ha venido experimentando el Sistema Hidroelectrico Miguel Aleman, hasta su desaparicion total, para dar prioridad al suministro de agua potable por medio del sistema de bombeo Cutzamala, que alimenta en forma importante a la Ciudad de Mexico y al Estado de Mexico. En este documento el autor describe el proyecto de construccion de la subestacion San Bernabe; se mencionan las experiencias tecnologicas obtenidas durante su construccion y se ilustra su ubicacion geografica, asi como un diagrama unifilar de la misma

[Irrigation in colostomies].

Science.gov (United States)

Campo, Juana; Lecona, Ana; Caparrós, M Rosario; Barbero, M Antonia; Javier Cerdán, F

2002-01-01

The degree of acceptation of irrigation from a colostomy varies ostensibly from some cases to others, therefore, we study what occurs in our medium, separating those patients which have previously undergone other procedures (Group A) from those patients who have been informed and trained about the immediate postoperative period (Group B). 48 patients, 22 or 46% of these patients were considered not apt for irrigation. Of the 26 to whom this procedure was proposed, 14 or 54% accepted. Of these, 5 or 36% abandoned its use while 9 continued its use; this is 64% of those who accepted this procedure, 35% of those to whom it was proposed and 19% of the total study group. 189 patients. This procedure was not recommended to 95 patients, 50%. Of the 94 patients to whom this procedure was proposed, 65 or 69% accepted. Of these, 22 or 34% abandoned its use while 43 continued its use; this is 66% of those; who accepted this procedure, 46% of those to whom it was proposed and 23% of the total study group. In our medium, the practice of irrigation oscillates between 19 and 23% of patients who have undergone a colostomy, without any significant difference referring to the moment when a patient started this procedure. A first report on this study was submitted in the III National Congress for Nursing in Colostomies.

Clinical value of colonic irrigation in patients with continence disturbances.

Science.gov (United States)

Briel, J W; Schouten, W R; Vlot, E A; Smits, S; van Kessel, I

1997-07-01

Continence disturbances, especially fecal soiling, are difficult to treat. Irrigation of the distal part of the large bowel might be considered as a nonsurgical alternative for patients with impaired continence. This study is aimed at evaluating the clinical value of colonic irrigation. Thirty-two patients (16 females; median age, 47 (range, 23-72) years) were offered colonic irrigation on an ambulatory basis. Sixteen patients suffered from fecal soiling (Group I), whereas the other 16 patients were treated for fecal incontinence (Group II). Patients were instructed by enterostomal therapists how to use a conventional colostomy irrigation set to obtain sufficient irrigation of the distal part of their large bowel. Patients with continence disturbances during the daytime were instructed to introduce 500 to 1,000 ml of warm (38 degrees C) water within 5 to 10 minutes after they passed their first stool. In addition, they were advised to wait until the urge to defecate was felt. Patients with soiling during overnight sleep were advised to irrigate during the evening. To determine clinical outcome, a detailed questionnaire was used. Median duration of follow-up was 18 months. Ten patients discontinued irrigation within the first month of treatment. Symptoms resolved completely in two patients. They believed that there was no need to continue treatment any longer. Irrigation had no effect in two patients. Despite the fact that symptoms resolved, six patients discontinued treatment because they experienced pain (n = 2) or they considered the irrigation to be too time-consuming (n = 4). Twenty-two patients are still performing irrigations. Most patients irrigated the colon in the morning after the first stool was passed. Time needed for washout varied between 10 and 90 minutes. Frequency of irrigations varied from two times per day to two times per week. In Group I, irrigation was found to be beneficial in 92 percent of patients, whereas 60 percent of patients in Group II

Effects of irrigation strategies and soils on field grown potatoes

DEFF Research Database (Denmark)

Ahmadi, Seyed Hamid; Plauborg, Finn; Andersen, Mathias Neumann

2011-01-01

Root distribution of field grown potatoes (cv. Folva) was studied in 4.32m2 lysimeters and subjected to full (FI), deficit (DI), and partial root-zone drying (PRD) irrigation strategies. Drip irrigation was applied for all irrigations. Irrigations were run in three different soils: coarse sand......, loamy sand, and sandy loam. Irrigation treatments started after tuber bulking and lasted until final harvest with PRD and DI receiving 65% of FI. Potatoes irrigated with water-saving irrigation techniques (PRD and DI) did not show statistically different dry root mass and root length density (RLD, cm...... density in the furrow. Most roots accumulated in the surface layers of coarse sand as compared to the other soil types. In the deep soil profile (30–70 cm) a higher root density was found in loamy sand compared with the sandy loam and coarse sand. Approximately twice the amounts of roots were found below...

Biochar enhances yield and quality of tomato under reduced irrigation

DEFF Research Database (Denmark)

Saleem Akhtar, Saqib; Li, Guitong; Andersen, Mathias Neumann

2014-01-01

tBiochar is an amendment that can be used for enhancing soil water storage which may increase cropproductivity. The objective of this study was to investigate the effects of biochar on physiology, yield andquality of tomato under different irrigation regimes. From early flowering to fruit maturity...... stages, theplants were subjected to full irrigation (FI), deficit irrigation (DI) and partial root-zone drying irrigation(PRD) and two levels of biochar (0% and 5% by weight). In FI, the plants were irrigated daily to pot waterholding capacity while in DI and PRD, 70% of FI was irrigated on either...... the whole or one side of the pots,respectively. In PRD, irrigation was switched between sides when the soil water content of the dry sidedecreased to 15%. The results showed that addition of biochar increased the soil moisture contents in DIand PRD, which consequently improved physiology, yield, and quality...

Agro-ecology and irrigation technology : comparative research on farmer-managed irrigation systems in the Mid-hills of Nepal

NARCIS (Netherlands)

Parajuli, U.N.

1999-01-01

Design and management of irrigation infrastructure in farmer managed irrigation systems (FMISs) are strongly influenced by social and agro-ecological conditions of an area. This thesis analyzes the elements of social and agro-ecological conditions in FMISs in the mid-hills of Nepal and

Modelling the economic trade-offs of irrigation pipeline investments ...

African Journals Online (AJOL)

The Soil Water Irrigation Planning and Energy Management (SWIP-E) mathematical programming model was developed and applied in this paper to provide decision support regarding the optimal mainline pipe diameter, irrigation system delivery capacity and size of the irrigation system. SWIP-E unifies the interrelated ...

Irrigation and fertigation frequencies with nitrogen in the watermelon culture

Directory of Open Access Journals (Sweden)

Carlos Newdmar Vieira Fernandes

2014-06-01

Full Text Available This study evaluates the influence of different irrigation frequencies and different nitrogen fertigation frequencies on the growth performance of the watermelon (Citrullus lanatus culture. Two experiments were conducted at the Paraguay farm in the Cruz municipality, Ceará, Brazil. They was randomized blocks design with six treatments and four replications. The irrigation frequency experiment consisted of the application of different irrigation frequencies. The treatments were: DM - daily irrigation in the morning with 100% daily dosage; DT - daily irrigation in the afternoon, with 100% daily dosage; DMT - twice daily irrigation, with 50% daily dosage in the morning and 50% daily dosage in the afternoon; 2D - irrigation every two days; 3D - irrigation every three days and 4D - irrigation every four days. To the experiment with different nitrogen fertigation frequencies, the treatments used were: 2F - 2 fertigations in a cycle; 4F - 4 fertigations in a cycle; 8F - 8 fertigations in a cycle; 16F - 16 fertigations in a cycle; 32F - 32 fertigations in a cycle and 64F - 64 fertigations in a cycle. We evaluated the marketable yield (PC, fruit weight (M, polar diameter (DP, equatorial diameter (DE, shell thickness (EC and soluble solids (SS. The irrigation frequency treatments influenced all variables significantly, with twice daily irrigation (DMT, 50% in the morning and the 50% in the afternoon promoting the highest productivity (69.79 t ha-1. The different frequencies of fertigation also significantly influenced all variables, except for the shell thickness, the highest yield (80.69 t ha-1 being obtained with treatment 64 fertigations in a cycle.

Simulation-based optimization framework for reuse of agricultural drainage water in irrigation.

Science.gov (United States)

Allam, A; Tawfik, A; Yoshimura, C; Fleifle, A

2016-05-01

A simulation-based optimization framework for agricultural drainage water (ADW) reuse has been developed through the integration of a water quality model (QUAL2Kw) and a genetic algorithm. This framework was applied to the Gharbia drain in the Nile Delta, Egypt, in summer and winter 2012. First, the water quantity and quality of the drain was simulated using the QUAL2Kw model. Second, uncertainty analysis and sensitivity analysis based on Monte Carlo simulation were performed to assess QUAL2Kw's performance and to identify the most critical variables for determination of water quality, respectively. Finally, a genetic algorithm was applied to maximize the total reuse quantity from seven reuse locations with the condition not to violate the standards for using mixed water in irrigation. The water quality simulations showed that organic matter concentrations are critical management variables in the Gharbia drain. The uncertainty analysis showed the reliability of QUAL2Kw to simulate water quality and quantity along the drain. Furthermore, the sensitivity analysis showed that the 5-day biochemical oxygen demand, chemical oxygen demand, total dissolved solids, total nitrogen and total phosphorous are highly sensitive to point source flow and quality. Additionally, the optimization results revealed that the reuse quantities of ADW can reach 36.3% and 40.4% of the available ADW in the drain during summer and winter, respectively. These quantities meet 30.8% and 29.1% of the drainage basin requirements for fresh irrigation water in the respective seasons. Copyright © 2016 Elsevier Ltd. All rights reserved.

Alkaline Sodium Hypochlorite Irrigant and Its Chemical Interactions

Directory of Open Access Journals (Sweden)

Patricia P. Wright

2017-09-01

Full Text Available Endodontic irrigating solutions may interact chemically with one another. This is important, because even when solutions are not admixed, they will come into contact with one another during an alternating irrigation technique, forming unwanted by-products, which may be toxic or irritant. Mixing or alternating irrigants can also reduce their ability to clean and disinfect the root canal system of teeth by changing their chemical structure with subsequent loss of the active agent, or by inducing precipitate formation in the root canal system. Precipitates occlude dental tubules, resulting in less penetration of antimicrobials and a loss of disinfection efficacy. Sodium hypochlorite is not only a very reactive oxidizing agent, but is also the most commonly used endodontic irrigant. As such, many interactions occurring between it and other irrigants, chelators and other antimicrobials, may occur. Of particular interest is the interaction between sodium hypochlorite and the chelators EDTA, citric acid and etidronate and between sodium hypochlorite and the antimicrobials chlorhexidine, alexidine, MTAD and octenisept.

Field evaluation of deficit irrigation effects on tomato growth ...

African Journals Online (AJOL)

Two field experiments were conducted using a common tomato cultivar (GS12) to assess the effect of deficit irrigation (DI) regimes on tomato growth performance, and on root-knot nematode Meloidogyne javanica galling and abundance. Irrigation treatments consisted of five irrigation regimes: 20%, 40%, 60%, 80% and ...

Surge flow irrigation under short field conditions in Egypt

NARCIS (Netherlands)

Ismail, S.M.; Depeweg, H.; Schultz, E.

2004-01-01

Several studies carried out in long furrows have shown that surge flow irrigation offers the potential of increasing the efficiency of irrigation. The effects of surge flow in short fields, such as in Egypt, are still not well known, however. To investigate the effect of surge flow irrigation in

Evaluation of mulched drip irrigation for cotton in arid Northwest China

NARCIS (Netherlands)

Wang, Z.; Jin, M.; Simunek, J.; van Genuchten, M.T.

2014-01-01

Field experiments were conducted in arid Southern Xinjiang, Northwest China, for 3 years to evaluate sustainable irrigation regimes for cotton. The experiments involved mulched drip irrigation during the growing season and flood irrigation afterward. The drip irrigation experiments included control

Green and blue water footprint reduction in irrigated agriculture: effect of irrigation techniques, irrigation strategies and mulching

NARCIS (Netherlands)

Chukalla, Abebe Demissie; Krol, Martinus S.; Hoekstra, Arjen Ysbert

2015-01-01

Consumptive water footprint (WF) reduction in irrigated crop production is essential given the increasing competition for freshwater. This study explores the effect of three management practices on the soil water balance and plant growth, specifically on evapotranspiration (ET) and yield (Y) and

Normative structures, collaboration and conflict in irrigation; a case study of the Pillaro North Canal Irrigation System, Ecuadorian Highlands

Directory of Open Access Journals (Sweden)

Jaime Hoogesteger

2015-03-01

Full Text Available This paper analyzes conflict and collaboration and their relation to normative structures based on a case study of the history and external interventions of the Píllaro North Canal Irrigation System in the Ecuadorian Highlands. It does so by using Ostrom’s framework for analyzing the sustainability of socio-ecological systems together with an analysis of the normative structures that define the governance systems through which the interactions in irrigation systems are mediated. I argue that the external interventions by the state and NGOs imposed a new governance system that undermined the existing normative structures and related organizations, leading to internal conflicts. The case study suggests that a reformulation of irrigation policies and state intervention methodologies in user managed supra-community irrigation systems in the Andes could lead to higher levels of cooperation.

Strategy of Irrigation Branch in Russia

Science.gov (United States)

Zeyliger, A.; Ermolaeva, O.

2012-04-01

At this moment, at the starting time of the program on restoration of a large irrigation in Russia till 2020, the scientific and technical community of irrigation branch does not have clear vision on how to promote a development of irrigated agriculture and without repeating of mistakes having a place in the past. In many respects absence of a vision is connected to serious backlog of a scientific and technical and informational and technological level of development of domestic irrigation branch from advanced one. Namely such level of development is necessary for the resolving of new problems in new conditions of managing, and also for adequate answers to new challenges from climate and degradation of ground & water resources, as well as a rigorous requirement from an environment. In such important situation for irrigation branch when it is necessary quickly generate a scientific and technical politics for the current decade for maintenance of translation of irrigated agriculture in the Russian Federation on a new highly effective level of development, in our opinion, it is required to carry out open discussion of needs and requirements as well as a research for a adequate solutions. From political point of view a framework organized in FP6 DESIRE 037046 project is an example of good practice that can serve as methodical approach how to organize and develop such processes. From technical point of view a technology of operational management of irrigation at large scale presents a prospective alternative to the current type of management based on planning. From point of view ICT operational management demands creation of a new platform for the professional environment of activity. This platform should allow to perceive processes in real time, at their partial predictability on signals of a straight line and a feedback, within the framework of variability of decision making scenarious, at high resolution and the big ex-awning of sensor controls and the gauges

Automation in irrigation process in family farm with Arduino platform

Directory of Open Access Journals (Sweden)

Kianne Crystie Bezerra da Cunha

2016-03-01

Full Text Available The small farmers tend not to use mechanical inputs in the irrigation process due to the high cost than conventional irrigation systems have and in other cases, the lack of knowledge and technical guidance makes the farmer theme using the system. Thus, all control and monitoring are made by hand without the aid of machines and this practice can lead to numerous problems from poor irrigation, and water waste, energy, and deficits in production. It is difficult to deduce when to irrigate, or how much water applied in cultivation, measure the soil temperature variables, temperature, and humidity, etc. The objective of this work is to implement an automated irrigation system aimed at family farming that is low cost and accessible to the farmer. The system will be able to monitor all parameters from irrigation. For this to occur, the key characteristics of family farming, Arduino platform, and irrigation were analyzed.

Description of gravity cores from San Pablo Bay and Carquinez Strait, San Francisco Bay, California

Science.gov (United States)

Woodrow, Donald L.; John L. Chin,; Wong, Florence L.; Fregoso, Theresa A.; Jaffe, Bruce E.

2017-06-27

Seventy-two gravity cores were collected by the U.S. Geological Survey in 1990, 1991, and 2000 from San Pablo Bay and Carquinez Strait, California. The gravity cores collected within San Pablo Bay contain bioturbated laminated silts and sandy clays, whole and broken bivalve shells (mostly mussels), fossil tube structures, and fine-grained plant or wood fragments. Gravity cores from the channel wall of Carquinez Strait east of San Pablo Bay consist of sand and clay layers, whole and broken bivalve shells (less than in San Pablo Bay), trace fossil tubes, and minute fragments of plant material.

Pond and Irrigation Model (PIM): a tool for simultaneously evaluating pond water availability and crop irrigation demand

Science.gov (United States)

Ying Ouyang; Gary Feng; Theodor D. Leininger; John Read; Johnie N. Jenkins

2018-01-01

Agricultural ponds are an important alternative source of water for crop irrigation to conserve surface and ground water resources. In recent years more such ponds have been constructed in Mississippi and around the world. There is currently, however, a lack of a tool to simultaneously estimate crop irrigation demand and pond water availability. In this study, a Pond-...

Irrigation Scheduling for Green Bell Peppers Using Capacitance Soil Moisture Sensors

NARCIS (Netherlands)

Zotarelli, L.; Dukes, M.D.; Scholberg, J.M.S.; Femminella, K.; Munoz-Carpena, R.

2011-01-01

Vegetable production areas are intensively managed with high inputs of fertilizer and irrigation. The objectives of this study were to evaluate the interaction between N-fertilizer rates and irrigation scheduling using soil moisture sensor irrigation controllers (SMS) on yield, irrigation water use

78 FR 34123 - Notice of Inventory Completion: San Francisco State University NAGPRA Program, San Francisco, CA

Science.gov (United States)

2013-06-06

... completion of an inventory of human remains and associated funerary objects under the control of the San....R50000] Notice of Inventory Completion: San Francisco State University NAGPRA Program, San Francisco, CA... NAGPRA Program has completed an inventory of human remains and associated funerary objects, in...

78 FR 21403 - Notice of Inventory Completion: San Francisco State University NAGPRA Program, San Francisco, CA

Science.gov (United States)

2013-04-10

... completion of an inventory of human remains and associated funerary objects under the control of the San....R50000] Notice of Inventory Completion: San Francisco State University NAGPRA Program, San Francisco, CA... NAGPRA Program has completed an inventory of human remains and associated funerary objects, in...

Landsat-based monitoring of crop water demand in the San Joaquin Valley

Science.gov (United States)

Johnson, L.; Trout, T.; Wang, D.; Melton, F. S.

2010-12-01

Fresh water resources are becoming increasingly scarce in California due to urbanization, environmental regulation, and groundwater depletion. The strain is projected to worsen under various climate change scenarios and is exacerbated by declining water delivery infrastructure. It is estimated that irrigated agriculture currently commands more than 70% of the state’s water supply, and many growers are striving to improve water use efficiency in order to help maintain the state’s rich agricultural heritage. Remote sensing technology offers the potential to monitor cropland evapotranspiration (ET) regionally, while making farm-based irrigation scheduling more practical, convenient, and possibly more accurate. Landsat5-TM imagery was used in this study to monitor basal crop evapotranspiration (ETcb), which is primarily related to plant transpiration, for several San Joaquin Valley fields throughout the 2008 growing season. A ground-based digital camera was used to measure fractional cover of 48 study fields planted to 18 different crop types (row crops, grains, orchard, and vineyard) of varying maturity over 12 dates coinciding with Landsat overpasses. Landsat L1T terrain-corrected images were atmospherically corrected to surface reflectance by an implementation of the Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS), then converted to normalized difference vegetation index (NDVI) on a per-pixel basis. A strong linear relationship between NDVI and fractional cover was observed (r2=0.96), and a resulting conversion equation was used to transform all imagery to fractional cover. Conversion equations previously developed by use of weighting lysimeters were then used to transform fractional cover to basal crop coefficient (Kcb; ratio of crop transpiration plus a small diffusive soil evaporation component to reference ET). Finally, measurements of grass reference ET (ETo) from the California Irrigation Management Information System were used to

Syringe irrigation: blending endodontics and fluid dynamics

NARCIS (Netherlands)

Boutsioukis, C.; van der Sluis, L.W.M.; Basrani, B.

2015-01-01

Syringe irrigation remains a widely used irrigant delivery method during root canal treatment. An interdisciplinary approach involving well-established methods from the field of fluid dynamics can provide new insights into the mechanisms involved in cleaning and disinfection of the root canal system

Syringe irrigation: blending endodontics and fluid dynamics

NARCIS (Netherlands)

Boutsioukis, Christos; van der Sluis, Lucas; Basrani, Bettina

2015-01-01

This book reviews the available information on bacterial disinfection in endodontics, with emphasis on the chemical treatment of root canals based on current understanding of the process of irrigation. It describes recent advances in knowledge of the chemistry associated with irrigants and delivery

The phenology of malaria mosquitos in irrigated rice fields in Mali

NARCIS (Netherlands)

Klinkenberg, E.; Takken, W.; Huibers, F.P.; Touré, Y.T.

2003-01-01

A field study was carried out in the large-scale rice irrigation scheme of the Office du Niger in Mali to investigate the relation between anopheline mosquito larval development and small-scale differences in irrigation practices, such as water level, irrigation application and irrigation frequency.

Alternate partial root-zone drying irrigation improves fruit quality in tomatoes

DEFF Research Database (Denmark)

Sun, Y.; Holm, Peter Engelund; Liu, Fulai

2014-01-01

Alternate partial root-zone drying (PRD) irrigation and deficit irrigation (DI) are water-saving irrigation strategies. Here, comparative effects of PRD and DI on fruit quality of tomato (Solanum lycopersicum L.) were investigated. The results showed that the irrigation treatments had no effect o...

Multiple-use Management of Irrigation Systems: Technical Constraints and Challenges

Science.gov (United States)

Gowing, J.; Li, Q.; Mayilswami, C.; Gunawardhana, K.

It is now widely recognised that many irrigation systems, originally planned only for irrigation supply, are de facto multiple-use systems. However, the importance of non- irrigation uses (such as bathing, laundry, livestock watering and fishing), to the liveli- hoods of the rural poor has generally been ignored. This has significant implications for irrigation engineers, water resources managers and other decision-makers. An im- proved understanding of competition and complementarity between these uses and irrigation demands is essential for effective multiple-use management of irrigation systems.This paper presents a study of multiple-use management, where the focus is on integrating aquaculture within irrigation systems with and without secondary storage. The Lower Bhavani scheme in South India and Mahaweli System H in Sri- Lanka were selected as representative smallholder irrigation schemes: - The Lower Bhavani scheme comprises a 200km contour canal serving a command area of 78,500ha. Apart from the main dam, there are no storage structures within the irriga- tion system. - Mahaweli System H comprises a command area of 43,000ha served by three main canals. The feature of particular interest in this scheme is the large number of secondary storage structures (known locally as tanks), which are in- tegrated within the canal network. It is apparent from these two sites and from studies elsewhere that non-irrigation uses are important to the livelihoods of the local peo- ple, but these uses are largely opportunistic. The failure to give explicit recognition to non-irrigation uses has important implications for assessments of economic per- formance and water productivity of irrigation systems. However, any attempt to give proper recognition to these alternative uses also has implication for irrigation project management. This paper describes a detailed study of water management in the two irrigation systems. The method of investigation involves in-depth studies in

Reform of irrigation management and investment policy in African development

Directory of Open Access Journals (Sweden)

KW Easter

2004-11-01

Full Text Available This paper examines the reform of water and irrigation management in Africa and compares it with similar reforms in Asia.  Several things are evident from the review.  First, Sub-Saharan Africa (SSA is at an earlier stage of irrigation development and reform than Asia.  Second, the articulated need for reform is much stronger in Asia than it is in SSA.  Third, the productivity of small-scale irrigated farms is significantly lower in SSA compared to Asia.  Thus any irrigation investment strategy in SSA should be different from Asia and focus on increasing small-farm productivity as well as small-scale irrigation projects.  Finally, all direct government irrigation investments should be done jointly with decisions regarding the type of project management.

Dwarf cashew growth irrigated with saline waters

Directory of Open Access Journals (Sweden)

Hugo Orlando Carvallo Guerra

2009-12-01

Full Text Available The cashew production is one of the most important agricultural activities from the social-economical viewpoint for the North East of Brazil; besides to produce a great deal of hand labor, it is very important as an exporting commodity. The inadequate use of irrigation in the semi arid regions of the North East of Brazil has induced soil salinization and consequently problems for the irrigated agriculture. In spite of this, few works have been conducted to study the effect of saline stress on the growth and development of the cashew. Because of the lack of information for this crop, an experiment was conducted to study the effect of salinity stress on the phytomass production and nutrient accumulation on the different organs of the precocious dwarf cashew (Anacardium occidentale L. clone CCP76. The study was conducted under controlled conditions using as statistical scheme a randomized block design factorial with six replicates. Five salinity treatments were considered for the irrigation water (electrical conductivities of 0.8, 1.6, 2.4, 3.2 and 4.0 dS m-1 at 25oC. The increasing in salinity of the irrigation water reduced the phytomass at different organs of the studied plant. The nitrogen, phosphorus, potassium, chloride and sodium in the plant varied with the salinity of the irrigation water according with the part of the plant analyzed; in some parts increased, in others decreased, in others increased initially and decreased afterwards, and finally, in other part of the plant the salinity of the irrigation water did not affect the nutrient concentration.

Optimization of irrigation water in stone fruit and table grapes

Science.gov (United States)

de la Rosa, Jose Mª; Castillo, Cristina; Temnani, Abdel; Pérez-Pastor, Alejandro

2017-04-01

In water scarcity areas, it must be highlighted that the maximum productions of the crops do not necessarily imply maximum profitability. Therefore, during the last years a special interest in the development of deficit irrigation strategies based on significant reductions of the seasonal ET without affecting production or quality has been observed. The strategies of regulated deficit irrigation (RDI) are based on the reduction of water supply during non critical periods, the covering of water needs during critical periods and maximizing, at the same time, the production by unit of applied water. The main objective of this experiment was to implement, demonstrate and disseminate a sustainable irrigation strategy based on deficit irrigation to promote its large scale acceptance and use in woody crops in Mediterranean agroecosystems, characterized by water scarcity, without affecting the quality standards demanded by exportation markets. Five demonstration plots were established in representative crops of the irrigating community of Campotejar (Murcia, Spain): i) Peach trees, cv. catherina in the "Periquitos" farm; ii) Apricot trees, cv. "Red Carlet" in "La Hoya del Fenazar" farm; iii) Nectarine trees, cv. Viowhite in "Agrícola Don Fernando" farm; iv) Table grape, cv "Crimson Seedless" in "La Hornera" farm; and v) Paraguayan cv. carioca in "The Hornera" farm. In each demonstration plot, at least two irrigation treatments were established: i) Control (CTL), irrigated to ensure non-limiting water conditions (120% of crop evapotranspiration) and ii) Regulated deficit irrigation (RDI) irrigated as CTL during critical periods and decreasing irrigation in non-critical periods. The plant water status indicators evaluated were midday stem water potential and Trunk Diameter Fluctuation derived indices: maximum daily shrinkage (MDS) and trunk daily growth rate (TGR); vegetative growth of the different crops from trunk diameter and pruning dry weight, fruit growth and fruit

LOW COST SMART SOLAR POWERED AUTOMATIC IRRIGATION SYSTEM

OpenAIRE

Hinsermu Alemayehu*, Kena Likassa

2016-01-01

In developing countries Photovoltaic energy can find many applications in agriculture, providing electrical energy in various cases, particularly OFF grid and desert area. Today Modern irrigation methods in developing country are needed to fulfill the food demands. Although in these countries Ethiopia, there are many diesel engine operated and rare solar operated water pumps for irrigation; but due to the running cost of diesel and capital cost of photovoltaic irrigation system. So Photovolta...

Agricultural irrigated land-use inventory for Polk County, Florida, 2016

Science.gov (United States)

Marella, Richard L.; Berry, Darbi; Dixon, Joann F.

2017-08-16

An accurate inventory of irrigated crop acreage is not available at the level of resolution needed to better estimate agricultural water use or to project future water demands in many Florida counties. A detailed digital map and summary of irrigated acreage was developed for Polk County, Florida, during the 2016 growing season. This cooperative project between the U.S. Geological Survey and the Office of Agricultural Water Policy of the Florida Department of Agriculture and Consumer Services is part of an effort to improve estimates of water use and projections of future demands across all counties in the State. The irrigated areas were delineated by using land-use data provided by the Florida Department of Agriculture and Consumer Services, along with information obtained from the South and Southwest Florida Water Management Districts consumptive water-use permits. Delineations were field verified between April and December 2016. Attribute data such as crop type, primary water source, and type of irrigation system were assigned to the irrigated areas.The results of this inventory and field verification indicate that during the 2016 growing seasons (spring, summer, fall, and winter), an estimated 88,652 acres were irrigated within Polk County. Of the total field-verified crops, 83,995 acres were in citrus; 2,893 acres were in other non-citrus fruit crops (blueberries, grapes, peaches, and strawberries); 621 acres were in row crops (primarily beans and watermelons); 1,117 acres were in nursery (container and tree farms) and sod production; and 26 acres were in field crops including hay and pasture. Of the total inventoried irrigated acreage within Polk County, 98 percent (86,566 acres) was in the Southwest Florida Water Management District, and the remaining 2 percent (2,086 acres) was in the South Florida Water Management District.About 85,788 acres (96.8 percent of the acreage inventoried) were irrigated by a microirrigation system, including drip, bubblers, and

Collaborative Resilience to Episodic Shocks and Surprises: A Very Long-Term Case Study of Zanjera Irrigation in the Philippines 1979–2010

Directory of Open Access Journals (Sweden)

Ruth Yabes

2015-07-01

Full Text Available This thirty-year case study uses surveys, semi-structured interviews, and content analysis to examine the adaptive capacity of Zanjera San Marcelino, an indigenous irrigation management system in the northern Philippines. This common pool resource (CPR system exists within a turbulent social-ecological system (SES characterized by episodic shocks such as large typhoons as well as novel surprises, such as national political regime change and the construction of large dams. The Zanjera nimbly responded to these challenges, although sometimes in ways that left its structure and function substantially altered. While a partial integration with the Philippine National Irrigation Agency was critical to the Zanjera’s success, this relationship required on-going improvisation and renegotiation. Over time, the Zanjera showed an increasing capacity to learn and adapt. A core contribution of this analysis is the integration of a CPR study within an SES framework to examine resilience, made possible the occurrence of a wide range of challenges to the Zanjera’s function and survival over the long period of study. Long-term analyses like this one, however rare, are particularly useful for understanding the adaptive and transformative dimensions of resilience.

Column leaching experiments of a uranium ore by atomizing irrigation technique

International Nuclear Information System (INIS)

Zeng Yingying; Lei Zeyong; Chen Haihui

2007-01-01

Column leaching experiments ora uranium ore were made by atomizing irrigation technique. The leaching results are compared with the results obtained by spray irrigation and drip irrigation techniques respectively under the same conditions of column leaching experiments. The results show that the atomizing irrigation technique has more uniform solution distribution, higher leaching rate, shorter leaching period, and less ratio of liquid to solid. Consequently, the atomizing irrigation technique is suitable to the ore. (authors)

Evaluation of best management practices under intensive irrigation using SWAT model

OpenAIRE

Dechmi, Farida; Skhiri, Ahmed

2013-01-01

Land management practices such as conservation tillage and optimum irrigation are routinely used to reduce non-point source pollution and improve water quality. The calibrated and validated SWAT-IRRIG model is the first modified SWAT version that reproduces well the irrigation return flows (IRF) when the irrigation source is outside of the watershed. The application of this SWAT version in intensive irrigated systems permits to better evaluate the best management practices (BMPs) in such syst...

75 FR 15611 - Safety Zone; United Portuguese SES Centennial Festa, San Diego Bay, San Diego, CA

Science.gov (United States)

2010-03-30

...-AA00 Safety Zone; United Portuguese SES Centennial Festa, San Diego Bay, San Diego, CA AGENCY: Coast... navigable waters of the San Diego Bay in support of the United Portuguese SES Centennial Festa. This... Centennial Festa, which will include a fireworks presentation originating from a tug and barge combination in...

Prospective controlled trial comparing colostomy irrigation with "spontaneous-action" method.

OpenAIRE

Williams, N S; Johnston, D

1980-01-01

Thirty randomly selected patients with permanent colostomies entered a prospective controlled trial comparing colostomy irrigation with spontaneous action. Each patient was interviewed and examined before irrigation was begun and again after the technique had been used for three months. Each then reverted to spontaneous action for a further three months and was then reassessed. Eight patients abandoned irrigation and 22 (73%) adhered to the protocol. Irrigation caused no mishaps or complicati...

Soil Suitability Classification of Tomas Irrigation Scheme for Irrigated ...

African Journals Online (AJOL)

The need for sustainable rice production in Nigeria cannot be over-emphasized. Since rice can be grown both under rain-fed and irrigated conditions, the need for soil suitability evaluation becomes very necessary in order for supply to meet up with demand. Six land qualities viz; climate, soil physical properties, drainage, ...

Technical Analysis of In-Valley Drainage Management Strategies for the Western San Joaquin Valley, California

Science.gov (United States)

Presser, Theresa S.; Schwarzbach, Steven E.

2008-01-01

The western San Joaquin Valley is one of the most productive farming areas in the United States, but salt-buildup in soils and shallow groundwater aquifers threatens this area?s productivity. Elevated selenium concentrations in soils and groundwater complicate drainage management and salt disposal. In this document, we evaluate constraints on drainage management and implications of various approaches to management considered in: *the San Luis Drainage Feature Re-Evaluation (SLDFRE) Environmental Impact Statement (EIS) (about 5,000 pages of documentation, including supporting technical reports and appendices); *recent conceptual plans put forward by the San Luis Unit (SLU) contractors (i.e., the SLU Plans) (about 6 pages of documentation); *approaches recommended by the San Joaquin Valley Drainage Program (SJVDP) (1990a); and *other U.S. Geological Survey (USGS) models and analysis relevant to the western San Joaquin Valley. The alternatives developed in the SLDFRE EIS and other recently proposed drainage plans (refer to appendix A for details) differ from the strategies proposed by the San Joaquin Valley Drainage Program (1990a). The Bureau of Reclamation (USBR) in March 2007 signed a record of decision for an in-valley disposal option that would retire 194,000 acres of land, build 1,900 acres of evaporation ponds, and develop a treatment system to remove salt and selenium from drainwater. The recently proposed SLU Plans emphasize pumping drainage to the surface, storing approximately 33% in agricultural water re-use areas, treating selenium through biotechnology, enhancing the evaporation of water to concentrate salt, and identifying ultimate storage facilities for the remaining approximately 67% of waste selenium and salt. The treatment sequence of reuse, reverse osmosis, selenium bio-treatment, and enhanced solar evaporation is unprecedented and untested at the scale needed to meet plan requirements. All drainage management strategies that have been proposed

Streamflow Prediction in Ungauged, Irrigated Basins

Science.gov (United States)

Zhang, M.; Thompson, S. E.

2016-12-01

The international "predictions in ungauged basins" or "PUB" effort has broadened and improved the tools available to support water resources management in sparsely observed regions. These tools have, however, been primarily focused on regions with limited diversion of surface or shallow groundwater resources. Incorporating anthropogenic activity into PUB methods is essential given the high level of development of many basins. We extended an existing stochastic framework used to predict the flow duration curve to explore the effects of irrigation on streamflow dynamics. Four canonical scenarios were considered in which irrigation water was (i) primarily sourced from water imports, (ii) primarily sourced from direct in-channel diversions, (iii) sourced from shallow groundwater with direct connectivity to stream channels, or (iv) sourced from deep groundwater that is indirectly connected to surface flow via a shallow aquifer. By comparing the predicted flow duration curves to those predicted by accounting for climate and geomorphic factors in isolation, specific "fingerprints" of human water withdrawals could be identified for the different irrigation scenarios, and shown to be sensitive to irrigation volumes and scheduling. The results provide a first insight into PUB methodologies that could be employed in heavily managed basins.

Solar-thermal jet pumping for irrigation

Science.gov (United States)

Clements, L. D.; Dellenback, P. A.; Bell, C. A.

1980-01-01

This paper describes a novel concept in solar powered irrigation pumping, gives measured performance data for the pump unit, and projected system performance. The solar-thermal jet pumping concept is centered around a conventional jet eductor pump which is commercially available at low cost. The jet eductor pump is powered by moderate temperature, moderate pressure Refrigerant-113 vapor supplied by a concentrating solar collector field. The R-113 vapor is direct condensed by the produced water and the two fluids are separated at the surface. The water goes on to use and the R-113 is repressurized and returned to the solar field. The key issue in the solar-thermal jet eductor concept is the efficiency of pump operation. Performance data from a small scale experimental unit which utilizes an electrically heated boiler in place of the solar field is presented. The solar-thermal jet eductor concept is compared with other solar irrigation concepts and optimal application situations are identified. Though having lower efficiencies than existing Rankine cycle solar-thermal irrigation systems, the mechanical and operational simplicity of this concept make it competitive with other solar powered irrigation schemes.

Behaviour Of Saline Irrigation Water Components In Pakistani Barley And Calcareous Soil Under Scheduling Irrigation Using Neutron Scattering Technique

International Nuclear Information System (INIS)

RIZK, M.A.

2010-01-01

This study aims to investigate the behaviour of cation uptake by Pakistani barley (genotype PK-30163) as affected by saline irrigation water, as well as cation distribution within the soil profile. This experiment was carried out at Soil and Water Research Department, Nuclear Research Centre, Atomic Energy Authority, Inshas, Egypt. The soil was transferred from Wadi Sudr (South Sinai, Egypt). It is salted affected soil (calcareous soil, EC = 4.3 dS/m) and was irrigated using ground water irrigation (12.5 dS/m). Nine used lysimeters were irrigated with three artificial saline water (0.3, 4 and 8 dS/m) using drip irrigation system. The irrigation schedule was carried out using neutron scattering technique according to the hydro physical properties of the soil. Pakistani barley (halophytic plant) was used to remove salts from the soil especially sodium cations. The cation uptake and cation distribution (Na, K, Ca, Mg) within the soil profile were studied.The data indicated that roots of barley collected within 0-15 cm layer showed high cation uptake that made the salt concentrations in this layer low. Sodium uptake ratio was 43, 37 and 47% from total cation uptake by using fresh water (0.3 dS/m), 4 and 8 dS/m, respectively. The maximum uptake for Na, K, Ca and Mg was 20.51, 19.13, 3.98 and 12.81 g/lys at 5.69, 3.05, 6.56 and 4.15 dS/m, respectively. It was found that Pakistani barley preferred Mg uptake rather than Ca uptake.

Grey mould development in greenhouse tomatoes under drip and furrow irrigation

OpenAIRE

Aissat , Kamel; Nicot , Philippe ,; Guechi , Abdelhadi; Bardin , Marc; Chibane , Mohamed

2008-01-01

Several methods can be used to provide water to plants in cropping systems where irrigation is necessary. For instance, drip irrigation has recently received much attention due to its advantages for water conservation. The type of irrigation can also impact the development of several pathogens responsible for soilborne diseases. Here, we studied the effect of drip irrigation and furrow irrigation on the development of grey mould, caused by the airborne fungus Botrytis cinerea, on tomato plant...

Using Automation to Improve Surface Irrigation Management

Science.gov (United States)

In the Lower Mississippi Water Resource Area (WRA 08), also called the Mid-South, 2 million ha of cropland (80% of the irrigated farmland) employ surface irrigation, almost equally divided between furrow (52%) and controlled flooding (48%). Because Mid-South farmers experience less-than-optimal surf...

Technical efficiency of irrigated vegetable production among ...

African Journals Online (AJOL)

This study was carried out to analyse the technical efficiency of irrigated vegetable production among smallholder farmers in the guinea savannah, Nigeria, and determine the cost and returns on irrigated vegetable production. Two-stage sampling technique was used, purposive selection of two states and three Local ...

Stakeholder analysis in the management of irrigation in Kampili area

Science.gov (United States)

Jumiati; Ali, M. S. S.; Fahmid, I. M.; Mahyuddin

2018-05-01

Irrigation has appreciable contribution in building food security, particularly rice crops. This study aims to analyze the role of stakeholders involved in distributing of irrigation water. The study was conducted in the Kampili Irrigation Area in South Sulawesi Province Indonesia, the data were obtained through observation and interviews with stakeholders involved, and analysed by stakeholder analysis, based on the interests and power held by the actors. This analysis is intended to provide an optimal picture of the expected role of each stakeholder in the management of irrigation resources. The results show that there were many stakeholders involved in irrigation management. In the arrangement of irrigation distribution there was overlapping authority of the stakeholders to its management, every stakeholder had different interests and power between each other. The existence have given positive and negative values in distributing irrigation water management, then in the stakeholder collaboration there was contestation between them. This contestation took place between the agriculture department, PSDA province, the Jeneberang River Region Hall, the Farmers Group and the P3A.

Research advances on thereasonable water resources allocation in irrigation district

DEFF Research Database (Denmark)

Xuebin, Qi; Zhongdong, Huang; Dongmei, Qiao

2015-01-01

The rational allocation of water resources for irrigation is important to improve the efficiency in utilization of water resources and ensuring food security, but also effective control measures need to be in place for the sustainable utilization of water resources in an irrigation area. The prog......The rational allocation of water resources for irrigation is important to improve the efficiency in utilization of water resources and ensuring food security, but also effective control measures need to be in place for the sustainable utilization of water resources in an irrigation area...... mechanism of water resources is not perfect, the model for optimal water resources allocation is not practical, and the basic conditions for optimal allocation of water resources is relatively weak. In order to solve those problems in water resources allocation practice, six important as?pects must...... in irrigation districts, studying the water resources control technology in irrigation districts by hydrology ecological system, studying the technologies of real?time risk dispatching and intelligent management in irrigation districts, and finally studying the technology of cou?pling optimal allocation...

Exploring Monte Carlo methods

CERN Document Server

Dunn, William L

2012-01-01

Exploring Monte Carlo Methods is a basic text that describes the numerical methods that have come to be known as "Monte Carlo." The book treats the subject generically through the first eight chapters and, thus, should be of use to anyone who wants to learn to use Monte Carlo. The next two chapters focus on applications in nuclear engineering, which are illustrative of uses in other fields. Five appendices are included, which provide useful information on probability distributions, general-purpose Monte Carlo codes for radiation transport, and other matters. The famous "Buffon's needle proble

Technical descriptions of ten irrigation technologies for conserving energy

Energy Technology Data Exchange (ETDEWEB)

Harrer, B.J.; Wilfert, G.L.

1983-05-01

Technical description of ten technologies which were researched to save energy in irrigated agriculture are presented. These technologies are: well design and development ground water supply system optimization, column and pump redesign, variable-speed pumping, pipe network optimization, reduced-pressure center-pivot systems, low-energy precision application, automated gated-pipe system, computerized irrigation scheduling, and instrumented irrigation scheduling. (MHR)

Specialized Monte Carlo codes versus general-purpose Monte Carlo codes

International Nuclear Information System (INIS)

Moskvin, Vadim; DesRosiers, Colleen; Papiez, Lech; Lu, Xiaoyi

2002-01-01

The possibilities of Monte Carlo modeling for dose calculations and optimization treatment are quite limited in radiation oncology applications. The main reason is that the Monte Carlo technique for dose calculations is time consuming while treatment planning may require hundreds of possible cases of dose simulations to be evaluated for dose optimization. The second reason is that general-purpose codes widely used in practice, require an experienced user to customize them for calculations. This paper discusses the concept of Monte Carlo code design that can avoid the main problems that are preventing wide spread use of this simulation technique in medical physics. (authors)

The Effect of Different Levels of Irrigation and Nitrogen Fertilizer on Yield and Water Use Efficiency of Potato in Subsurface Drip Irrigation

Directory of Open Access Journals (Sweden)

Mohammad Jolaini

2017-06-01

Full Text Available Introduction: After wheat, rice and corn, potato is the fourth most important food plant in the world. In comparison with other species, potato is very sensitive to water stress because of its shallow root system: approximately 85% of the root length is concentrated in the upper 0.3-0.4 m of the soil. Several studies showed that drip irrigation is an effective method for enhancing potato yield. Fabeiro et al. (2001 concluded that tuber bulking and ripening stages were found to be the most sensitive stages of water stress with drip irrigation. Water deficit occurring in these two growth stages could result in yield reductions. Wang et al. (2006 investigated the effects of drip irrigation frequency on soil wetting pattern and potato yield. The results indicated that potato roots were not limited in wetted soil volume even when the crop was irrigated at the highest frequency while high frequency irrigation enhanced potato tuber growth and water use efficiency (WUE. Though information about irrigation and N management of this crop is often conflicting in the literature, it is accepted generally that production and quality are highly influenced by both N and irrigation amounts and these requirements are related to the cropping technique. Researches revealed that nitrogen fertilizers play a special role in the growth, production and quality of potatoes. Materials and Methods: A factorial experiment in randomized complete block design with three replications was carried out during two growing seasons. Studied factors were irrigation frequency (I1:2 and I2:4 days interval and nitrogen fertilizer levels (applying 100 (N1, 75 (N2 and 50 (N3 % of the recommended amount. Nitrogen fertilizer was applied through irrigation water. In each plot two rows with within-and between-row spacing of 45 and 105 cm and 20 m length. The amount of nitrogen fertilizer for the control treatment was determined by soil analysis (N1. In all treatments, nitrogen fertilizer

Effects of different deficit irrigation on sugar accumulation of pineapple during development

Science.gov (United States)

Feng, Haiyan; Du, Liqing; Liu, Shenghui; Zhang, Xiumei

2017-08-01

The potted pineapple cultivar ‘Comte de paris’ was used to study the influence of deficit irrigation on fruit sugar accumulation in greenhouse during the fruit enlargement period. The study included a control (normal irrigation) and two treatment groups, moderate deficit (50% of the control irrigation) and severe deficit (25% of the control irrigation). The results indicated that the deficit irrigation significantly decreased the sucrose accumulation. The sucrose content in the fruits of moderate deficit irrigation was the lowest. During the mature period, the deficit irrigation decreased the sucrose phosophate synthase activity(SPS) an increased the sucrose synthase (SS) and neutral invertase (NI). The moderate deficit irrigation significantly improved the acid invertase activity(AI). However, it was inhibited by the severe deficit irrigation. In general, the moderate treatment reduced the SPS activity and enhanced the NI and AI activities, while the severe treatment decreased the SPS and AI activities.

The management perspective on the performance of the irrigation subsector

OpenAIRE

Nijman, C.

1993-01-01

INVESTMENT IN IRRIGATION has been immense in the past. Estimated average annual investments of US$ 15 billion makes irrigation the largest subsector of the agricultural sector, that is itself by far the largest sector of development investment. Since the mid-1960s the awareness spread that the performance of irrigation investments was far below its potential. The size of this underperformance is well represented by Seckler's alarming conclusion that the average irrigation investment costs twi...

Performance of BATAN-SANS instrument

Energy Technology Data Exchange (ETDEWEB)

Ikram, Abarrul; Insani, Andon [National Nuclear Energy Agency, P and D Centre for Materials Science and Technology, Serpong (Indonesia)

2003-03-01

SANS data from some standard samples have been obtained using BATAN-SANS instrument in Serpong. The experiments were performed for various experimental set-ups that involve different detector positions and collimator lengths. This paper describes the BATAN-SANS instrument briefly as well as the data taken from those experiments and followed with discussion of the results concerning the performance and calibration of the instrument. The standard samples utilized in these experiments include porous silica, polystyrene-poly isoprene, silver behenate, poly ball and polystyrene-poly (ethylene-alt-propylene). Even though the results show that BATAN-SANS instrument is in good shape, but rooms for improvements are still widely open especially for the velocity selector and its control system. (author)

Is the Revitalisation of Smallholder Irrigation Schemes (RESIS ...

African Journals Online (AJOL)

2013-09-30

Sep 30, 2013 ... including rainwater harvesting, flood recession, flood water spreading, river ... Smallholder irrigation systems can comprise farmers who use shared or ...... on Irrigation and Drainage, 15-17 November 2006, Aventura. Swadini.

Irrigation-water quality during 1976 irrigation season in the Sulphur Creek basin, Yakima and Benton counties, Washington

Science.gov (United States)

Boucher, P.R.; Fretwell, M.O.

1982-01-01

A water-quality-sampling network was designed for the Sulphur Creek basin to observe the effects of farming practices on irrigation. Sediment and nutrient yield, discharge, and water temperature data were collected during the 1976 irrigation season and the following fall and winter. The suspended-sediment yield of the basin during this period was 2.0 tons per acre of irrigated cropland. Only about 3% of the net outflow of sediment occurred during the nonirrigation season. The yield computed by subbasin ranged from 0.7 to 7 tons per acre, depending mainly on land slope, but a high percentage of orchard land in the subbasins was probably also significant in reducing loads. Nutrient outflows during the study period were 1,180,000 pounds of nitrogen and 120,000 pounds of phosphorous. Nitrate-plus-nitrite represent 70% of the nitrogen outflow in the irrigation season and 84% in the nonirrigation season. The monitoring network was discontinued at the end of the study period, due largely to insufficient farmer participation. Network sensitivity in the control subbasins was inadequate to detect the effects of a planned demonstration program of best management practices. (USGS)

A case for historic joint rupture of the San Andreas and San Jacinto faults

OpenAIRE

Lozos, Julian C.

2016-01-01

The San Andreas fault is considered to be the primary plate boundary fault in southern California and the most likely fault to produce a major earthquake. I use dynamic rupture modeling to show that the San Jacinto fault is capable of rupturing along with the San Andreas in a single earthquake, and interpret these results along with existing paleoseismic data and historic damage reports to suggest that this has likely occurred in the historic past. In particular, I find that paleoseismic data...

Estimation of furrow irrigation sediment loss using an artificial neural network

Science.gov (United States)

The area irrigated by furrow irrigation in the U.S. has been steadily decreasing but still represents about 20% of the total irrigated area in the U.S. Furrow irrigation sediment loss is a major water quality issue and a method for estimating sediment loss is needed to quantify the environmental imp...

Monte Carlo principles and applications

Energy Technology Data Exchange (ETDEWEB)

Raeside, D E [Oklahoma Univ., Oklahoma City (USA). Health Sciences Center

1976-03-01

The principles underlying the use of Monte Carlo methods are explained, for readers who may not be familiar with the approach. The generation of random numbers is discussed, and the connection between Monte Carlo methods and random numbers is indicated. Outlines of two well established Monte Carlo sampling techniques are given, together with examples illustrating their use. The general techniques for improving the efficiency of Monte Carlo calculations are considered. The literature relevant to the applications of Monte Carlo calculations in medical physics is reviewed.

Irrigation method does not affect wild bee pollinators of hybrid sunflower

Directory of Open Access Journals (Sweden)

Hillary Sardiñas

2016-09-01

Full Text Available Irrigation method has the potential to directly or indirectly influence populations of wild bee crop pollinators nesting and foraging in irrigated crop fields. The majority of wild bee species nest in the ground, and their nests may be susceptible to flooding. In addition, their pollination of crops can be influenced by nectar quality and quantity, which are related to water availability. To determine whether different irrigation methods affect crop pollinators, we compared the number of ground-nesting bees nesting and foraging in drip- and furrow-irrigated hybrid sunflower fields in the Sacramento Valley. We found that irrigation method did not impact wild bee nesting rates or foraging bee abundance or bee species richness. These findings suggest that changing from furrow irrigation to drip irrigation to conserve water likely will not alter hybrid sunflower crop pollination.

Assessing the groundwater recharge under various irrigation schemes in Central Taiwan

Science.gov (United States)

Chen, Shih-Kai; Jang, Cheng-Shin; Lin, Zih-Ciao; Tsai, Cheng-Bin

2014-05-01

The flooded paddy fields can be considered as a major source of groundwater recharge in Central Taiwan. The risk of rice production has increased notably due to climate change in this area. To respond to agricultural water shortage caused by climate change without affecting rice yield in the future, the application of water-saving irrigation is the substantial resolution. The System of Rice Intensification (SRI) was developed as a set of insights and practices used in growing irrigated rice. Based on the water-saving irrigation practice of SRI, impacts of the new methodology on the reducing of groundwater recharge were assessed in central Taiwan. The three-dimensional finite element groundwater model (FEMWATER) with the variable boundary condition analog functions, was applied in simulating groundwater recharge under different irrigation schemes. According to local climatic and environmental characteristics associated with SRI methodology, the change of infiltration rate was evaluated and compared with the traditional irrigation schemes, including continuous irrigation and rotational irrigation scheme. The simulation results showed that the average infiltration rate in the rice growing season decreased when applying the SRI methodology, and the total groundwater recharge amount of SRI with a 5-day irrigation interval reduced 12% and 9% compared with continuous irrigation (6cm constant ponding water depth) and rotational scheme (5-day irrigation interval with 6 cm initial ponding water depth), respectively. The results could be used as basis for planning long-term adaptive water resource management strategies to climate change in Central Taiwan. Keywords: SRI, Irrigation schemes, Groundwater recharge, Infiltration

Prospects and Constraints of Household Irrigation Practices ...

African Journals Online (AJOL)

Constraints and prospects of hand dug wells related to household irrigation were assessed in Hayelom watershed (~1045 ha), by evaluating groundwater suitability for irrigation, soil quality and impact of intervention. 181 hand dug wells have come into existence in the watershed due to intervention and benefiting about ...

Participatory Irrigation Management and Irrigation Water Use Efficiency in Maize Production: Evidence from Zhangye City, Northwestern China

Directory of Open Access Journals (Sweden)

Qing Zhou

2017-10-01

Full Text Available Water has become increasingly scarce in northwestern China due to climate change, economic growth and burgeoning population. Improving agriculture water use efficiency is of strategic significance in promoting socio-economic water productivity for arid and semi-arid inland river basins. Based on the household-level data collected in Zhangye City, which is located in the middle reaches of Heihe River Basin (HRB in northwestern China, irrigation water use efficiency (IWUE of maize is estimated based on stochastic frontier analysis. The impacts of influential factors, especially the participatory irrigation management (PIM through water user associations (WUAs, on IWUE were further examined. Results show that the estimated average Technical efficiency (TE and IWUE of maize production are 0.74 and 0.24, respectively. The participation level in irrigation management is very low, with only 40% of the respondents participating in WUA meetings. In addition, most have a relatively superficial understanding of the roles and management scheme of WUAs. Empirical results show that though significantly positive, the magnitude of the impact of PIM on IWUE is relatively small. Households that participated in WUA meetings achieved only 0.002% higher IWUEs than those have never participated in. WUAs are not operating with their designed objectives. Consequently, reform of the traditional management form of WUAs to make them more transparent, fair, and extensively participated in among farmers is in urgently need. In addition, we also find that water price, source of irrigation water, irrigation technology adoption and famers’ education level and farming experience also have significant positive impacts on IWUE.

Coordinated research project of the use of nuclear and related techniques in assessment of irrigation schedules of field crops to increase effective use of water in irrigation projects

International Nuclear Information System (INIS)

Anac, M.S.; Tuzel, I.H.; Anac, D.

1995-01-01

The study aimed at determining the followings; water consumptions. irrigation water requirements of new cotton variety N 84; specific growth stages of cotton which are less sensitive to stress so that the irrigation could be avoided without significant yield decrease; and interactions between deficit irrigation and nitrogen fertilizer use. The experiment was set up with 6 irrigation and three nitrogen fertilizer (0.60 , 120 kg.ha sup -1 ) treatments. The irrigation treatments employed single stress at vegetative, flowering and boll formation stages, in addition to full irrigation, continuous stress and the traditional practice. In stress conditions available soil water depleted to 75 - 80 %, whereas in normal irrigation the depletion was 40 % in 0.90 m. of root zone. In full irrigation treatment 8 irrigations were applied, whereas 3 or 4 irrigations were needed in continuous stress conditions. The number of irrigations were 6 or 7 for other stress treatments. Irrigation water applications varied form 424 to 751 mm. Seasonal ET were ranged between 659 and 899 mm. The highest monthly ET in august for all of the treatments. Daily ET were found to vary from 2.2 to 12.1 mm/day. The seed cotton yields, ky values and yield - N indices have indicated that the vegetative state was more sensitive to water stress. The stress at boll formation stage had slight effects on these parameters. Under limited water resource conditions, vegetative growth period of cotton should be given preference for irrigation, followed by flowering period. Omitting irrigation in boll formation period would result in 4.3 to 9.1 % water savings. Yield changes with respect to N rates showed that high N doses are accompanied by high yields. Nitrogen recoveries either from fertilizers or soil revealed high uptakes in full irrigation conditions. Nitrogen use efficiencies were also high in these conditions. Average of three years put forth that 19% of N in stress conditions and 29% in full irrigation were

Limited irrigation research and infrared thermometry for detecting water stress

Science.gov (United States)

The USDA-ARS Limited Irrigation Research Farm, located outside of Greeley Colorado, is an experiment evaluating management perspectives of limited irrigation water. An overview of the farm systems is shown, including drip irrigation systems, water budgeting, and experimental design, as well as preli...

Water-Yield Relations of Drip Irrigated Watermelon in Temperate Climatic Conditions

Directory of Open Access Journals (Sweden)

Pejić Borivoj

2016-08-01

Full Text Available The objective of the study, conducted in Vojvodina a northern part of the Serbia Republic, was to analyse the effect of drip irrigation on yield, evapotranspiration and water productivity of watermelon (Cirullus lanatus Thunb. grown with plasticulture. Irrigation was scheduled on the basis of water balance method. Daily evapotranspiration was computed using the reference evapotranspiration and crop coefficient. The yield of watermelon in irrigation conditions (37,28 t/ha was significantly higher compared to non irrigated (9,98 t/ha. Water used on evapotranspiration in irrigation conditions was 398 mm and 117 mm on non irrigated variant. The crop yield response factor of 1,04 for the whole growing season reveals that relative yield decrease was nearly equal to the rate of evapotranspiration deficit. The values of irrigation water use efficiency and evapotranspiration water use efficiency were 9,93 kg/m3 and 10,29 kg/m3 respectively. The determined results could be used as a good platform for watermelon growers in the region, in terms of improvement of the optimum utilization of irrigation water.

Costs and benefits of satellite-based tools for irrigation management

Directory of Open Access Journals (Sweden)

Francesco eVuolo

2015-07-01

Full Text Available This paper presents the results of a collaborative work with farmers and a cost-benefit analysis of geospatial technologies applied to irrigation water management in the semi-arid agricultural area in Lower Austria. We use Earth observation (EO data to estimate crop evapotranspiration (ET and webGIS technologies to deliver maps and irrigation advice to farmers. The study reports the technical and qualitative evaluation performed during a demonstration phase in 2013 and provides an outlook to future developments. The calculation of the benefits is based on a comparison of the irrigation volumes estimated from satellite vs. the irrigation supplied by the farmers. In most cases, the amount of water supplied was equal to the maximum amount of water required by crops. At the same time high variability was observed for the different irrigation units and crop types. Our data clearly indicates that economic benefits could be achieved by reducing irrigation volumes, especially for water-intensive crops. Regarding the qualitative evaluation, most of the farmers expressed a very positive interest in the provided information. In particular, information related to crop ET was appreciated as this helps to make better informed decisions on irrigation. The majority of farmers (54% also expressed a general willingness to pay, either directly or via cost sharing, for such a service. Based on different cost scenarios, we calculated the cost of the service. Considering 20,000 ha regularly irrigated land, the advisory service would cost between 2.5 and 4.3 €/ha per year depending on the type of satellite data used. For comparison, irrigation costs range between 400 and 1000 €/ha per year for a typical irrigation volume of 2,000 cubic meters per ha. With a correct irrigation application, more than 10% of the water and energy could be saved in water-intensive crops, which is equivalent to an economic benefit of 40-100 €/ha per year.

Nitrate leaching beneath a containerized nursery crop receiving trickle or overhead irrigation.

Science.gov (United States)

Colangelo, D J; Brand, M H

2001-01-01

Container production of nursery crops is intensive and a potential source of nitrogen release to the environment. This study was conducted to determine if trickle irrigation could be used by container nursery producers as an alternative to standard overhead irrigation to reduce nitrogen release into the environment. The effect of overhead irrigation and trickle irrigation on leachate nitrate N concentration, flow-weighted nitrate N concentration, leachate volume, and plant growth was investigated using containerized rhododendron (Rhododendron catawbiense Michx. 'Album') supplied with a controlled-release fertilizer and grown outdoors on top of soil-monolith lysimeters. Leachate was collected over two growing seasons and overwinter periods, and natural precipitation was allowed as a component of the system. Precipitation accounted for 69% of the water entering the overhead-irrigated system and 80% of the water entering the trickle-irrigated system. Leachate from fertilized plants exceeded the USEPA limit of 10 mg L(-1) at several times and reached a maximum of 26 mg L(-1) with trickle irrigation. Average annual loss of nitrate N in leachate for fertilized treatments was 51.8 and 60.5 kg ha(-1) for the overhead and trickle treatments, respectively. Average annual flow-weighted concentration of nitrate N in leachate of fertilized plants was 7.2 mg L(-1) for overhead irrigation and 12.7 mg L(-1) for trickle irrigation. Trickle irrigation did not reduce the amount of nitrate N leached from nursery containers when compared with overhead irrigation because precipitation nullified the potential benefits of reduced leaching fractions and irrigation inputs provided under trickle irrigation.

La microrregión como unidad espacial para el estudio de los problemas ambientales. Situación de los recursos suelo, forestal e hídrico en la microrregión Platanar-La Vieja, cuenca del río San Carlos

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Francisco Rodríguez Barrientos

2007-05-01

Full Text Available A partir del ámbito territorial de las cuencas hidrográficas y de las divisiones políticoadministrativas, es posible determinar microrregiones con homogeneidad física,histórica, económica, social y cultural, en las cuales se puedan diseñar y ejecutar planes de manejo consensuados y participativos, algo indispensable para una política sostenible. En el trabajo se presentan elementos teóricos que ayudan a delimitar, precisar y operacionalizar elconcepto de microrregión, y se ofrecen las razones por las que se considera que las microcuencas de los ríos Platanar, Peje y La Vieja dentro de la cuenca del río San Carlos constituyen una microrregión. También se hace una caracterización de la microrregión Platanar-La Vieja, así como una descripción y análisis de los principales problemas que en ella afrontan los recursos suelo, forestal e hídrico.

Design and implementation of expert decision system in Yellow River Irrigation

Science.gov (United States)

Fuping, Wang; Bingbing, Lei; Jie, Pan

2018-03-01

How to make full use of water resources in the Yellow River irrigation is a problem needed to be solved urgently. On account of the different irrigation strategies in various growth stages of wheat, this paper proposes a novel irrigation expert decision system basing on fuzzy control technique. According to the control experience, expert knowledge and MATLAB simulation optimization, we obtain the irrigation fuzzy control table stored in the computer memory. The controlling irrigation is accomplished by reading the data from fuzzy control table. The experimental results show that the expert system can be used in the production of wheat to achieve timely and appropriate irrigation, and ensure that wheat growth cycle is always in the best growth environment.

11th International Conference on Monte Carlo and Quasi-Monte Carlo Methods in Scientific Computing

CERN Document Server

Nuyens, Dirk

2016-01-01

This book presents the refereed proceedings of the Eleventh International Conference on Monte Carlo and Quasi-Monte Carlo Methods in Scientific Computing that was held at the University of Leuven (Belgium) in April 2014. These biennial conferences are major events for Monte Carlo and quasi-Monte Carlo researchers. The proceedings include articles based on invited lectures as well as carefully selected contributed papers on all theoretical aspects and applications of Monte Carlo and quasi-Monte Carlo methods. Offering information on the latest developments in these very active areas, this book is an excellent reference resource for theoreticians and practitioners interested in solving high-dimensional computational problems, arising, in particular, in finance, statistics and computer graphics.

Energy savings potential from energy-conserving irrigation systems

Energy Technology Data Exchange (ETDEWEB)

Wilfert, G.L.; Patton, W.P.; Harrer, B.J.; Clark, M.A.

1982-11-01

This report systematically compares, within a consistent framework, the technical and economic characteristics of energy-conserving irrigation systems with those of conventional irrigation systems and to determine total energy savings. Levelized annual costs of owning and operating both energy-conserving and conventional irrigation systems have been developed and compared for all 17 states to account for the differences in energy costs and irrigation conditions in each state. Market penetration of energy-conserving systems is assessed for those systems having lower levelized annual costs than conventional systems performing the same function. Annual energy savings were computed by matching the energy savings per system with an assumed maximum market penetration of 100 percent in those markets where the levelized annual costs of energy-conserving systems are lower than the levelized annual costs of conventional systems.

Municipal Treated Wastewater Irrigation: Microbiological Risk Evaluation

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Antonio Lonigro

2008-06-01

Full Text Available Municipal wastewater for irrigation, though treated, can contain substances and pathogens toxic for humans and animals. Pathogens, although not harmful from an agronomical aspect, undoubtedly represent a major concern with regards to sanitary and hygienic profile. In fact, vegetable crops irrigated with treated wastewater exalt the risk of infection since these products can also be eaten raw, as well as transformed or cooked. Practically, the evaluation of the microbiological risk is important to verify if the microbial limits imposed by law for treated municipal wastewater for irrigation, are valid, thus justifying the treatments costs, or if they are too low and, therefore, they don’ t justify them. Different probabilistic models have been studied to assess the microbiological risk; among these, the Beta-Poisson model resulted the most reliable. Thus, the Dipartimento di Scienze delle Produzioni Vegetali of the University of Bari, which has been carrying out researches on irrigation with municipal filtered wastewater for several years, considered interesting to verify if the microbial limits imposed by the italian law n.185/03 are too severe, estimating the biological risk by the probabilistic Beta-Poisson model. Results of field trials on vegetable crops irrigated by municipal filtered wastewater, processed by the Beta-Poisson model, show that the probability to get infection and/or illness is extremely low, and that the actual italian microbial limits are excessively restrictive.

Physical-chemical effects of irrigation with treated wastewater on Dusky Red Latosol soil

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Vanessa Ribeiro Urbano

2015-11-01

Full Text Available The current water crisis underlines the importance of improving water management. The use of effluent from secondary treatment in agriculture can reduce the discharge of effluent into natural bodies and provide nutrients to crops. This study evaluated the physical and chemical properties of a Dusky Red Latosol soil that had been irrigated with treated wastewater. Conducted at the Center of Agricultural Sciences (CCA of Federal University of São Carlos (UFSCar, in Araras/São Paulo/Brazil, 18 undisturbed soil samples were collected and deposited on a constant-head permeameter in order to simulate the irrigation of five growth cycles of lettuce (Lactuca sativa L., organized in five different treatments and one control group. For each treatment 0.58 L, 1.16 L, 1.74 L, 2.32 L, and 2.90 L of treated wastewater and distilled water were applied . The treated wastewater came from a domestic waste treatment plant. After the water filtered through the soil, samples of treated wastewater were collected for analyses of electrical conductivity (EC, sodium adsorption ratio (SAR, turbidity, pH, Na, K, Mg, P and Ca and, in the soil the granulometry, complete fertility, exchangeable sodium percentage (ESP and saturated hydraulic conductivity (Ksat. The Ksat decreased, but did not alter the infiltration of water and nutrients in the soil. The concentration of nutrients in the soil increased, including Na, which raises the need for monitoring soil’s salinity. In conclusion, the application of wastewater did not cause damage to the physical properties of the soil, but resulted in a tendency towards salinization.

The Power to Resist: Irrigation Management Transfer in Indonesia

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Diana Suhardiman

2013-02-01

Full Text Available In the last two decades, international donors have promoted Irrigation Management Transfer (IMT as an international remedy to management problems in government irrigation systems in many developing countries. This article analyses the political processes that shape IMT policy formulation and implementation in Indonesia. It links IMT with the issue of bureaucratic reform and argues that its potential to address current problems in government irrigation systems cannot be achieved if the irrigation agency is not convinced about the need for management transfer. IMT’s significance cannot be measured only through IMT outcomes and impacts, without linking these with how the irrigation agency perceives the idea of management transfer in the first place, how this perception (redefines the agency’s position in IMT, and how it shapes the agency’s action and strategy in the policy formulation and implementation. I illustrate how the irrigation agency contested the idea of management transfer by referring to IMT policy adoption in 1987 and its renewal in 1999. The article concludes that for management transfer to be meaningful it is pertinent that the issue of bureaucratic reform is incorporated into current policy discussions.

Roles of the combined irrigation, drainage, and storage of the canal network in improving water reuse in the irrigation districts along the lower Yellow River, China

Science.gov (United States)

Liu, Lei; Luo, Yi; He, Chansheng; Lai, Jianbin; Li, Xiubin

2010-09-01

SummaryThe commonly used irrigation system in the irrigation districts (with a combined irrigation area of 3.334 × 10 6 ha) along the lower Yellow River of China is canal network. It delivers water from the Yellow River to the fields, collects surface runoff and drainage from cropland, and stores both of them for subsequent irrigation uses. This paper developed a new combined irrigation, drainage, and storage (CIDS) module for the SWAT2000 model, simulated the multiple roles of the CIDS canal system, and estimated its performance in improving water reuse in the irrigation districts under different irrigation and water diversion scenarios. The simulation results show that the annual evapotranspiration (ET) of the double-cropping winter wheat and summer maize was the highest under the full irrigation scenario (automatic irrigation), and the lowest under the no irrigation scenario. It varied between these two values when different irrigation schedules were adopted. Precipitation could only meet the water requirement of the double-cropping system by 62-96% on an annual basis; that of the winter wheat by 32-36%, summer maize by 92-123%, and cotton by 87-98% on a seasonal basis. Hence, effective irrigation management for winter wheat is critical to ensure high wheat yield in the study area. Runoff generation was closely related to precipitation and influenced by irrigation. The highest and lowest annual runoff accounted for 19% and 11% of the annual precipitation under the full irrigation and no irrigation scenarios, respectively. Nearly 70% of the annual runoff occurred during months of July and August due to the concentrated precipitation in these 2 months. The CIDS canals play an important role in delivering the diversion water from the Yellow River, intercepting the surface runoff and drainage from cropland (inflow of the CIDS canal) and recharging the shallow aquifer for later use. Roughly 14-26% of the simulated total flow in the CIDS canal system recharged

The impact of smallholder irrigation on household welfare: The case ...

African Journals Online (AJOL)

The potential of smallholder irrigated agriculture to enhance food security and alleviate rural poverty has led the South African Government to prioritise and invest significantly in irrigation establishment, rehabilitation and revitalisation. The question addressed in this study pertains to the extent to which smallholder irrigation ...

Tracking antibiotic resistance genes in soil irrigated with dairy wastewater

Science.gov (United States)

In southern Idaho, the application of dairy wastewater to agricultural soils is a widely used practice to irrigate crops and recycle nutrients. In this study, small-scale field plots were irrigated monthly (6 times) with dairy wastewater (100%), wastewater diluted to 50% with irrigation (canal) wate...

Irrigation water quality as indicator of sustainable rural development

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Trajković Slaviša

2004-01-01

Full Text Available The sustainable rural development more and more depends on the efficient usage of water resources. Most often, at least in one part of the year, the rain is not sufficient for plant growth and rain plant production significantly depends on the yearly precipitation variation. The increase and stability of the agricultural production is possible in the irrigation conditions. The most part (around 70% of the global water resources is used for food production. Irrigation water quality indicator is used to show if the available water resources have the required quality for application in agriculture. Irrigation is characterised by the complex water-plant-soil relationship, and in that eco-system the man as the end user of the irrigated fields occupies a very important place. That explains the difficulties in producing one universal classification of irrigation water quality. The paper analyses numerous water quality classifications from the aspect of the applicability on the quantifying of this indicator. The adopted classification should possess understandable, qualified and internationally comparable indicator. Thus, local classifications (Neigebauer, Miljkovic cannot be used for this indicator. United Nation Food and Agricultural Organization (FAO and US Salinity Laboratory (USSL classifications are used for the evaluation of the irrigation water quality throughout the world. FAO classification gives the complex picture of the usability of the irrigation water from the point of its influence on the soil and the plants. However, the scope of the analyses is not often suited to the needs of that classification, which makes it difficult to apply. The conclusion is that the USSL (US Salinity Laboratory classification is best suited to this range of chemical water analyses. The evaluation of the irrigation water quality indicator in the Juzna Morava river basin, upstream from the Toplica river estuary is given in this paper. Based on the obtained

Bureaucratic Reform in Irrigation: A Review of Four Case Studies

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Diana Suhardiman

2014-10-01

Full Text Available Poor performance of government-managed irrigation systems persists globally. This paper argues that addressing performance requires not simply more investment or different policy approaches, but reform of the bureaucracies responsible for irrigation management. Based on reform experiences in The Philippines, Mexico, Indonesia, and Uzbekistan, we argue that irrigation (policy reform cannot be treated in isolation from the overall functioning of government bureaucracies and the wider political structure of the states. Understanding of how and why government bureaucracies shape reform processes and outcomes is crucial to increase the actual significance of reforms. To demonstrate this, the paper links reform processes in the irrigation sector with the wider discourse of bureaucratic reform in the political science, public administration, and organisational science literature. Doing so brings to light the need for systematic comparative research on the organisational characteristic of the irrigation bureaucracies, their bureaucratic identities, and how these are shaped by various segments within the bureaucracies to provide the insights needed to improve irrigation systems performance.

Participatory management reforms in irrigation sector of sindh

International Nuclear Information System (INIS)

Lashari, B.K.

2009-01-01

Pakistan has been making efforts to restructuring the century old irrigation system by involving beneficiaries (water users) at various units of the irrigation system management. The main purposes of reforms are to improve O and M (Operation and Maintenance) of irrigation system, to make balance in expenditure and revenue, to improve crop production through efficient use of water, to maintain affordable drainage system and to adopt PWRM (Participatory Water Resource Management) approach. In these reforms, the Sindh provincial irrigation department was transferred to an autonomous body as SmA (Sindh Irrigation and Drainage Authority). Under SmA, CAWB (Canal Area Water Board) at each canal command area, water users association at watercourse level and Farmer Organizations at each secondary canal (Distributary/ Minor) command area were being formed. So far 335 FOs (Farmers Organizations) have been formed in Sindh. To evaluate the performance of FOs in their day to day activities such as water distribution, O and M of irrigation channels, conflict management and revenue (Abiana) collection, IMI (Institutional Maturity Index) of FOs is conducted. The objective IMI analysis was to assess the maturity of FOs in terms of organizational aspects, conflict resolution, financial aspects, water distribution, operation and maintenance, environmental aspects and capacity building of FOs. The IMI analyses identified the weaker aspects of the FOs and need of focus these aspects for improved performance of FOs through effective social mobilization and capacity building activities. (author)

Influence of local topography on precision irrigation management

Science.gov (United States)

Precision irrigation management is currently accomplished using spatial information about soil properties through soil series maps or electrical conductivity (EC measurements. Crop yield, however, is consistently influenced by local topography, both in rain-fed and irrigated environments. Utilizing ...

San Marco C-2 (San Marco-4) Post Launch Report No. 1

Science.gov (United States)

1974-01-01

The San Marco C-2 spacecraft, now designated San Marco-4, was successfully launched by a Scout vehicle from the San Marco Platform on 18 February 1974 at 6:05 a.m. EDT. The launch occurred 2 hours 50 minutes into the 3-hour window due co low cloud cover at the launch site. All spacecraft subsystems have been checked and are functioning normally. The protective caps for the two U.S. experiments were ejected and the Omegatron experiment activated on 19 February. The neutral mass spectrometer was activated as scheduled on 22 February after sufficient time to allow for spacecraft outgassing and to avoid the possibility of corona occurring. Both instruments are performing properly and worthwhile scientific data is being acquired.

Soil and water management in spate irrigation systems in Eritrea

NARCIS (Netherlands)

Hadera, M.T.

2001-01-01

Spate irrigation has been practised over 100 years in the Red Sea coastal zone of Eritrea such as the Sheeb area. Main problem of the spate irrigation system is water shortage caused by irregular rainfall in the highlands of Eritrea and breaching of the irrigation structures by destructive

Effects of seven different irrigation techniques on debris and the ...

African Journals Online (AJOL)

Aim: Conventional manual irrigation with a syringe and needle remains widely accepted technique in the irrigation procedures. However, its flushing action has some limitations. Currently, several techniques and systems are available and reported to improve the insufficiency of syringe irrigation. The aim of this study was to ...

77 FR 34988 - Notice of Inventory Completion: San Diego State University, San Diego, CA

Science.gov (United States)

2012-06-12

.... ACTION: Notice. SUMMARY: San Diego State University Archeology Collections Management Program has... that believes itself to be culturally affiliated with the human remains and associated funerary objects may contact San Diego State University Archeology Collections Management Program. Repatriation of the...

Shifting shoals and shattered rocks : How man has transformed the floor of west-central San Francisco Bay

Science.gov (United States)

Chin, John L.; Wong, Florence L.; Carlson, Paul R.

2004-01-01

San Francisco Bay, one of the world's finest natural harbors and a major center for maritime trade, is referred to as the 'Gateway to the Pacific Rim.' The bay is an urbanized estuary that is considered by many to be the major estuary in the United States most modified by man's activities. The population around the estuary has grown rapidly since the 1850's and now exceeds 7 million people. The San Francisco Bay area's economy ranks as one of the largest in the world, larger even than that of many countries. More than 10 million tourists are estimated to visit the bay region each year. The bay area's population and associated development have increasingly changed the estuary and its environment. San Francisco Bay and the contiguous Sacramento-San Joaquin Delta encompass roughly 1,600 square miles (4,100 km2) and are the outlet of a major watershed that drains more than 40 percent of the land area of the State of California. This watershed provides drinking water for 20 million people (two thirds of the State's population) and irrigates 4.5 million acres of farmland and ranchland. During the past several decades, much has been done to clean up the environment and waters of San Francisco Bay. Conservationist groups have even bought many areas on the margins of the bay with the intention of restoring them to a condition more like the natural marshes they once were. However, many of the major manmade changes to the bay's environment occurred so long ago that the nature of them has been forgotten. In addition, many changes continue to occur today, such as the introduction of exotic species and the loss of commercial and sport fisheries because of declining fish populations. The economy and population of the nine counties that surround the bay continue to grow and put increasing pressure on the bay, both direct and indirect. Therefore, there are mixed signals for the future health and welfare of San Francisco Bay. The San Francisco Bay estuary consists of three

Dos versiones de San Pascual Bailón por Carreño de Miranda

Directory of Open Access Journals (Sweden)

Gutiérrez Pastor, Ismael

2002-03-01

Full Text Available Conozco desde hace algún tiempo un lienzo de San Pascual Bailón arrodillado adorando el Santísimo Sacramento que, por sus características formales y de estilo, debe ser obra de Juan Carreño de Miranda (1627-1685, el pintor que sucedió Diego Velázquez y a Sebastián Herrera Barnuevo en el desempeño de las funciones de Pintor de Cámara de la reina viuda Doña Mariana de Austria y de su hijo el rey Carlos II. Su papel fue absolutamente fundamental en la pintura madrileña del Barroco, tanto por la progresión estilística que supone su propia obra, como por su labor de modelo y maestro de muchos pintores jóvenes de las generaciones siguientes. La pintura (fig. 1 representa a San Pascual Bailón arrodillado en el suelo, extasiado ante la contemplación de un cáliz con la hostia consagrada, que aparece posado sobre una tela roja que portan varias cabezas de querubines.…

Preferential flow, nitrogen transformations and 15N balance under urine-affected areas of irrigated and non-irrigated clover-based pastures

Science.gov (United States)

Pakro, Naser; Dillon, Peter

1995-12-01

Urine-affected areas can lead to considerable losses of N by leaching, ammonia volatilisation and denitrification from dairy pastures in the southeast of South Australia. Potable groundwater supplies are considered to have become contaminated by nitrate as a result of leaching from these leguminous pastures. Dairy cow urine, labelled with 15N urea, was applied to micro-plots and mini-lysimeters installed in two adjacent irrigated (white clover-rye grass) and non-irrigated (subterranean clover-annual grasses) paddocks of a dairy farm on four occasions representing different seasonal conditions. These experiments allowed measurement of nitrogen transformations, recovery of 15N in the pasture and soil, and leaching below various depths. Gaseous losses were calculated from the nitrogen balance. The results of the four experiments showed that within a day of urine application up to 40% of the applied urinary-N was leached below a depth of 150 mm as a result of macropore flow in the irrigated paddock, and up to 24% in the non-irrigated one. After application to the irrigated paddock 17% of the urinary-N moved immediately below 300 mm but only 2% below the 450-mm depth. The urinary-N remaining in the soil was converted from urea to ammonium within a day regardless of season. Within the first 7 days of application six times more nitrate was produced in summer than in winter. This has obvious implications for leaching potential. Leaching of 15N from the top 150 mm of soil, following urine applications in all seasons, was between 41% and 62% of the applied 15N in the irrigated paddock and 25-51% in the non-irrigated paddock. However, leaching losses measured at depths of 300 or 450 mm were smaller by a factor of 2-4. The leaching loss of 15N applied in spring in both paddocks was 41% below 150 mm and 12% below 450 mm. Recovery of 15N from the soil-plant system in the 450-nm deep lysimeters was ˜60% of that applied. Estimated ammonia was ˜9% of applied 15N with no paddock

Sensor-Based Model Driven Control Strategy for Precision Irrigation

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Camilo Lozoya

2016-01-01

Full Text Available Improving the efficiency of the agricultural irrigation systems substantially contributes to sustainable water management. This improvement can be achieved through an automated irrigation system that includes a real-time control strategy based on the water, soil, and crop relationship. This paper presents a model driven control strategy applied to an irrigation system, in order to make an efficient use of water for large crop fields, that is, applying the correct amount of water in the correct place at the right moment. The proposed model uses a predictive algorithm that senses soil moisture and weather variables, to determine optimal amount of water required by the crop. This proposed approach is evaluated against a traditional irrigation system based on the empirical definition of time periods and against a basic soil moisture control system. Results indicate that the use of a model predictive control in an irrigation system achieves a higher efficiency and significantly reduce the water consumption.

Response of potato to drip and gun irrigation systems

DEFF Research Database (Denmark)

Zhenjiang, Zhou; Andersen, Mathias Neumann; Plauborg, Finn

2015-01-01

The objective of this study was to evaluate effects of different irrigation and N fertilization regimes by gun irrigation and drip-fertigation on potato production, and subsequently optimize the supply of water and N fertilizer to the growth condition of the specific season and minimize nitrate......-fertigation system (DFdsNds) and two gun irrigation systems (GIdsN120 and GIaN120) to display the differences on growth, yield and water use efficiency of potato. All treatments were irrigated according to model simulated soil water content. For fertilization all treatments received a basic dressing at planting of P......, K, Mg and micronutrients, and in addition 120 kg N/ha in the gun irrigated treatments and 36 kg N/ha in the drip-fertigated. For the latter, portion of 20 kg N/ha was applied whenever plant N concentration approached a critical value as simulated by the Daisy model. As a result differences in soil...

Effect of irrigation and stainless steel drills on dental implant bed heat generation.

Science.gov (United States)

Bullon, B; Bueno, E F; Herrero, M; Fernandez-Palacin, A; Rios, J V; Bullon, P; Gil, F J

2015-02-01

The objective of this study is assessing the influence of the use of different drill types and external irrigation on heat generation in the bone. In-vitro study to compare two different sequences for implant-bed preparation by means of two stainless steels: precipitation-hardening stainless steel (AISI 420B) (K drills), and martensitic stainless steel (AISI 440) (S drills). Besides, the drilled sequences were realized without irrigation, and with external irrigation by means of normal saline solution at room temperature. The study was realized on bovine ribs using: K without irrigation (KSI) and with irrigation (KCI) and S without irrigation (SSI) and with irrigation (SCI) with five drills for each system. Each drill was used 100 times. Bone temperature was measured with a thermocouple immediately after drilled. Average bone temperature with irrigation was for K drills 17.58±3.32 °C and for S drills 16.66±1.30 °C. Average bone temperature without irrigation was for K drills 23.58±2.94 °C and for S drills 19.41±2.27 °C. Statistically significant differences were found between K without irrigation versus S with irrigation and K with irrigation (pstainless steel AISI 420B presents better mechanical properties and corrosion resistance than AISI440.

Greenhouse evaluation of deficit irrigation on the growth of tomato ...

African Journals Online (AJOL)

Deficit irrigation is considered to be an important approach for crop cultivation in dry regions where water resources are scarce. Deficit irrigation can be used also to decrease the level of infections by some moisturedependent plant pests and diseases such as root-knot nematode disease. Therefore, deficit irrigation at levels ...

Critical parameters for maize yield under irrigation farming in the ...

African Journals Online (AJOL)

This study examines the critical variables that determine maize yield under irrigation farming in the savanna ecological zone of Kwara State. Seventy-five soil samples were randomly collected from irrigation farm of Oke-Oyi irrigation project of the Lower Niger River Basin Development Authority Ilorin and bulked into 15 ...

Potentials for Supplemental Irrigation in Some Rainfall Areas of Imo ...

African Journals Online (AJOL)

In addition, there were up to five months of the year during which rainwater was much in deficit of evapotranspiration. All these stress the need for irrigation. Analysis of water quality (surface, groundwater, and rainfall runoff) showed their suitability for irrigation. Quantity assessment of supplemental irrigation during the dry ...

Comparative in situ X-ray Diffraction Study of San Carlos Olivine: Influence of Water on the 410 km Seismic Velocity Jump in Earth’s Mantle

Energy Technology Data Exchange (ETDEWEB)

J Chen; H Liu; J Girard

2011-12-31

A comparative study of the equation of states of hydrous (0.4 wt% H{sub 2}O) and anhydrous San Carlos olivine (<30 ppm H2O) was conducted using synchrotron X-rays up to 11 GPa in a diamond anvil cell (DAC) at ambient temperature. Both samples were loaded in the same high-pressure chamber of the DAC to eliminate the possible pressure difference in different experiments. The obtained compression data were fitted to the third-order Birch-Murnaghan equation of state, yielding a bulk modulus K{sub 0} = 123(3) GPa for hydrous olivine and K{sub 0} = 130(4) GPa for anhydrous olivine as K{sub 0}' is fixed at 4.6. Therefore, 0.4 wt% H{sub 2}2O in olivine results in a 5% reduction in bulk modulus. Previous studies reported bulk modulus reduction by water in olivine's high-pressure polymorph (wadsleyite), to which the transformation from olivine gives rise to the seismic discontinuity at 410 km depth. The new data results in a reduction in the magnitude of the discontinuity by 50% in v{sub P} and 30% in v{sub S} (for 1:5 water partitioning between olivine and wadsleyite) with respect to anhydrous mantle. Previous knowledge of the influence of water on this phase transition has been in opposition to a large amount of water [e.g., 200 ppm by Wood (1995)] existing at 410 km depth. Calculation of the seismic velocities based on newly available elasticity data of the hydrous phases indicates that the presence of water is favorable for the mineral composition model (pyrolite) and seismic observations in terms of the magnitude of the 410 km discontinuity.

CERN honours Carlo Rubbia

CERN Document Server

2009-01-01

Carlo Rubbia turned 75 on March 31, and CERN held a symposium to mark his birthday and pay tribute to his impressive contribution to both CERN and science. Carlo Rubbia, 4th from right, together with the speakers at the symposium.On 7 April CERN hosted a celebration marking Carlo Rubbia’s 75th birthday and 25 years since he was awarded the Nobel Prize for Physics. "Today we will celebrate 100 years of Carlo Rubbia" joked CERN’s Director-General, Rolf Heuer in his opening speech, "75 years of his age and 25 years of the Nobel Prize." Rubbia received the Nobel Prize along with Simon van der Meer for contributions to the discovery of the W and Z bosons, carriers of the weak interaction. During the symposium, which was held in the Main Auditorium, several eminent speakers gave lectures on areas of science to which Carlo Rubbia made decisive contributions. Among those who spoke were Michel Spiro, Director of the French National Insti...

Evolution of Corn Transpiration and Leaf Water Potential During Sprinkler Irrigation

OpenAIRE

Martínez-Cob, Antonio; Fernández-Navajas, Julián; Durán, Víctor; Cavero Campo, José

2009-01-01

Corn (Zea mays L.) transpiration during daytime solid-set sprinkler irrigation was analyzed on two neighbouring subplots to determine the effect of the transpiration reduction on water application efficiency. During each irrigation event, one subplot was irrigated (moist treatment) while the other was not (dry treatment). Transpiration rates were determined at each subplot by the heat balance method (Dynamax Flow4 System) before, during and after the irrigations. During irri...

Coupled Crop/Hydrology Model to Estimate Expanded Irrigation Impact on Water Resources

Science.gov (United States)

Handyside, C. T.; Cruise, J.

2017-12-01

A coupled agricultural and hydrologic systems model is used to examine the environmental impact of irrigation in the Southeast. A gridded crop model for the Southeast is used to determine regional irrigation demand. This irrigation demand is used in a regional hydrologic model to determine the hydrologic impact of irrigation. For the Southeast to maintain/expand irrigated agricultural production and provide adaptation to climate change and climate variability it will require integrated agricultural and hydrologic system models that can calculate irrigation demand and the impact of the this demand on the river hydrology. These integrated models can be used as (1) historical tools to examine vulnerability of expanded irrigation to past climate extremes (2) future tools to examine the sustainability of expanded irrigation under future climate scenarios and (3) a real-time tool to allow dynamic water resource management. Such tools are necessary to assure stakeholders and the public that irrigation can be carried out in a sustainable manner. The system tools to be discussed include a gridded version of the crop modeling system (DSSAT). The gridded model is referred to as GriDSSAT. The irrigation demand from GriDSSAT is coupled to a regional hydrologic model developed by the Eastern Forest Environmental Threat Assessment Center of the USDA Forest Service) (WaSSI). The crop model provides the dynamic irrigation demand which is a function of the weather. The hydrologic model includes all other competing uses of water. Examples of use the crop model coupled with the hydrologic model include historical analyses which show the change in hydrology as additional acres of irrigated land are added to water sheds. The first order change in hydrology is computed in terms of changes in the Water Availability Stress Index (WASSI) which is the ratio of water demand (irrigation, public water supply, industrial use, etc.) and water availability from the hydrologic model. Also

Wastewater Use in Irrigated Agriculture : Confronting the Livelihood ...

International Development Research Centre (IDRC) Digital Library (Canada)

Wastewater Use in Irrigated Agriculture : Confronting the Livelihood and Environmental Realities. Couverture du livre Wastewater Use in Irrigated Agriculture: Confronting the Livelihood and Environmental Realities. Directeur(s) : Christopher Scott, Naser I. Faruqui et Liqa Raschid. Maison(s) d'édition : CABI, IWMI, CRDI.

ARS irrigation research priorities and projects-An update

Science.gov (United States)

The USDA Agricultural Research Service focuses on six areas of research that are crucial to safe and effective use of all water resources for agricultural production: 1) Irrigation Scheduling Technologies for Water Productivity; 2) Water Productivity (WP) at Multiple Scales; 3) Irrigation Applicatio...

Effects of different irrigation methods on pepper yield and soilborne diseases incidence

Directory of Open Access Journals (Sweden)

Seral YÜCEL

2013-12-01

Full Text Available In this study, the effect of different irrigation strategies and irrigation methods on yields and the incidence of wilt (Fusarium oxysporum and root rot (Fusarium solani and Macrophomina phaseolina diseases causing significant yield losses on field grown processing red pepper is determined. Experiments were carried out at Topçu Station of the Soil and Water Resources Research Institute of Tarsus in 2010 and 2011. Karaisalı processing pepper (Capsicum annuum L. was used in the experiments. Three furrows and five drip irrigation treatments were used in the study. The disease incidence rates were found 8.0-18.2% in furrow irrigation plots and 4.5-10.0% in drip irrigation plots in 2010, while it was 3.4-9.7% in furrow irrigation plots and 2.2-4.5% in drip irrigation plots in 2011. Pepper yields ranged from 3 416 to 4 417 kg da-1 and 3 376 to 4 779 kg da-1 in drip irrigated plots in 2010 and 2011, respectively. However, yields varied between 3 172-3 559 kg da-1 and 2 932-4 150 kg da-1 in furrow irrigated plots in 2010 and 2011 growing seasons.

Water requirement and irrigation schedule for tomato in northern guinea savanna zone, Nigeria

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Ibraheem Alhassan

2015-06-01

Full Text Available Assessment of water requirement and irrigation schedule for tomato with the support of FAO-CROPWAT simulation model was carried out for Yola, Nigeria with the aim of planning irrigation schedules for tomato and develop recommendations for improve irrigation practices. The climatic data for 2012/2013 and soil properties of the study area were input into the program. Tomato crop properties were updated by the FAO data and three irrigation intervals were tested (7 and 10 days irrigation intervals and irrigation schedule of 10 days interval during initial and development stage and 6 days interval at mid and late season stages of tomato crop. The simulated results analysis for tomato according to the irrigation schedule showed that highest yield reduction of 16.2% was recorded with 10 days irrigation interval treatment and the least of 0.4% with irrigation interval of 10 days at first two growth stages and 6 days at last two stages. FAO-CROPWAT 8.0 can be used in planning proper irrigation schedule for tomato in Yola, Nigeria.

Yield and water use efficiency of irrigated soybean in Vojvodina, Serbia

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Pejić Borivoj

2012-01-01

Full Text Available Research was carried out at Rimski Šančevi experiment field of Institute of Field and Vegetable Crops in Novi Sad in the period 1993-2004. The experiment included an irrigated and non-irrigated control treatment. Irrigation water use efficiency (Iwue and evapotranspiration water use efficiency (ETwue were determined in order to assess the effectiveness of irrigation on soybean yield. The average yield increases of soybean due to irrigation practice was 0.82 t ha-1, ranging from 2.465 t ha-1 in years with limited precipitation and higher than average seasonal temperatures (2000 to 0 t ha-1 in rainy years (1996, 1997, 1999. Evapotranspiration water use efficiency (ETwue of soybean ranged from 0.11 kg m-3 to 1.36 kg m-3 with an average value of 0.66 kg m-3, while irrigation water use efficiency (Iwue varied from 0.11 kg m-3 to 1.04 kg m-3 with an average value of 0.56 kg m-3. Effect of irrigation on yield of soybean and results of both ETwue and Iwue which were similar to those obtained from the literature indicate that irrigation schedule of soybean in the study period was properly adapted to plant water requirements and water-physical soil properties. Determined values of ETwue and Iwue could be used for the planning, design and operation of irrigation systems, as well as for improving the production technology of soybean in the region.

Decadal Variation of Precipitation in Saudi Arabia induced by Agricultural Irrigation

Science.gov (United States)

Lo, M. H.; Wey, H. W.; Wada, Y.; IM, E. S.; Chien, R. Y.; Wu, R. J.

2017-12-01

Decadal variation of wet-season precipitation has been found in the arid region of central Saudi Arabia. 1980s has been a rather wet decade compared with the decades before. Previous studies have mentioned that the irrigation moisture may contribute to the precipitation anomalies in Saudi Arabia. In the current study, we show from observational data that the contribution of the variation comes mostly from February to May. As the irrigation is a localized forcing, we therefore use the Weather Research and Forecasting (WRF) Model to simulate the response of the land-atmosphere interaction to the wet soil moisture resulted from additional irrigation moisture supply. Preliminary result shows in the irrigated simulation that precipitation in central Saudi Arabia is enhanced, indicating the possible link between irrigation expansion in the 1980s and the decadal precipitation variation over central Saudi Arabia. We propose it is the anomalous convergence induced by irrigation as well as additional moisture that contribute to the enhanced precipitation over heavily irrigation region in the central Saudi Arabian. In addition, analysis on the daily precipitation from the WRF outputs indicates that positive rainfall anomalies tend to happen when there is rainfall originally; that is, irrigation enhances rainfall but not creates rainfall.

Stoma management in a tropical country: colostomy irrigation versus natural evacuation.

Science.gov (United States)

Leong, A F; Yunos, A B

1999-11-01

People with ostomies in Singapore were initially resistant to colostomy irrigation. This study, a prospective crossover study of 26 patients who underwent abdominoperineal resection, compared colostomy irrigation with the natural evacuation method. During the colostomy-irrigation phase of the study, all 26 patients reported an improvement in continence and fewer problems with sleep, sex, and skin complications compared to the natural-evacuation phase. The study also found a reduction in monthly expenses with colostomy irrigation compared to natural evacuation. Patient satisfaction scores were also superior during the colostomy-irrigation phase. This difference in satisfaction scores was less marked in those who were more than 1-year postsurgery than in those who were less than 1-year postsurgery. The difference in satisfaction between colostomy irrigation and natural evacuation scores was statistically significant in the group that was less than 1-year postsurgery, but not in the group that was more than 1-year postsurgery. The study concluded that colostomy irrigation after abdominoperineal resection is superior to natural evacuation in terms of cost and patient satisfaction and should be introduced soon after surgery.

The comparison between two irrigation regimens on the dentine wettability for an epoxy resin based sealer by measuring its contact angle formed to the irrigated dentine.

Science.gov (United States)

Mohan, Rayapudi Phani; Pai, Annappa Raghavendra Vivekananda

2015-01-01

The aim was to assess the influence of two irrigation regimens having ethylenediaminetetraacetic acid (EDTA) and ethylenediaminetetraacetic acid with cetrimide (EDTAC) as final irrigants, respectively, on the dentine wettability for AH Plus sealer by comparing its contact angle formed to the irrigated dentine. Study samples were divided into two groups (n = 10). The groups were irrigated with 3% sodium hypochlorite (NaOCl) solution followed by either 17% EDTA or 17% EDTAC solution. AH Plus was mixed, and controlled volume droplet (0.1 mL) of the sealer was placed on the dried samples. The contact angle was measured using a Dynamic Contact Angle Analyzer and results were analyzed using SPSS 21.0 and 2 sample t-test. There was a significant difference in the contact angle of AH Plus formed to the dentine irrigated with the above two regimens. AH Plus showed significantly lower contact angle with the regimen having EDTAC as a final irrigant than the one with EDTA (P contact angle of a sealer. EDTAC as a final irrigant facilitates better dentin wettability than EDTA for AH Plus to promote its better flow and adhesion.

Irrigation management of muskmelon with tensiometry

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Márcio José de Santana

2017-11-01

Full Text Available The production and consumption of muskmelon have been increasing (MELO et al., 2014, thus, information on techniques for higher field productions are necessary. The experiment described in the present work was conducted in the IFTM, Uberaba, State of Minas Gerais, Brazil, aiming to evaluate the muskmelon yield under different soil water tensions. A randomized block experimental design was used with five treatments (soil water tensions of 10, 20, 30, 40 and 50 kPa and four replications (plots of two rows of 14 plants. Two harvests were carried out and the fruit yield, stem diameter, number of fruits per plant and efficiency of water use were evaluated. Irrigation was performed with a drip irrigation system and managed with tensiometry. The cultivar Bonus n.2 was used with spacing of 1.0 x 0.6 m. The data of the variables were subjected to the F test and regression test. The treatments showed statistical differences in number of fruits per plant, fruit weight (fruit yield and stem diameter. The highest fruit yield found was 1.36 kg fruit-1 and the highest water use efficiency was 4.08 g mm-1 with irrigation for a soil water tension of 10 kPa. The lowest fruit yield was found with irrigation for a soil water tension of 50 kPa.

Irrigation and Rural Welfare: Implications of Schistosomiasis among ...

African Journals Online (AJOL)

This paper examines the effects of the prevalence of urinary schistosomiasis infection on the socio-economic health of irrigation farmers in the rural districts of Kazaure Area, Northern Nigeria. It first reviews some general consideration of irrigation environment and schistosomiasis, its major associated health problem.

Aflaj’s Irrigation Water Demand/Supply Ratio: Two Case Studies

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Abdullah Al-Ghafri

2006-01-01

Full Text Available Due to the geographical location of Oman in an arid zone, agricultural production depends fully on irrigation. The traditional irrigation systems (Aflaj, sing. falaj supply more than one third of water for agriculture. Falaj is defined in the context of this paper as a canal system which provides water for domestic and agricultural uses. Oman has 3,107 active Aflaj producing about 680 Mm3 of water per year. The main objective of this study was to estimate the irrigation performance of Aflaj in Oman. Falaj al-Dariz and al-Nujaid were chosen as case studies. Both Aflaj are located in an extremely arid environment, where the rainfall is low and evapotranspiration is high. The study utilized an approach to estimate the irrigation performance of Aflaj by considering the falaj as a single unit of irrigation. The irrigation demand/supply ratio (D/S was used in the analysis as a tool of evaluation. Date palm, the dominant crop irrigated by Aflaj, was selected for the analysis. In falaj al-Dariz the date palms were slightly under irrigated on a yearly basis. On a monthly basis, in winter, the D/S was below 0.6 and in summer it was above 1.0. On the other hand, falaj al-Nujaid was supplying too much water than the date palms needed all round the year. In winter the D/S ratio was as low as 0.25. Even in summer, the D/S ratio did not much exceed 1.0.

Evaluation of reservoir operation strategies for irrigation in the Macul Basin, Ecuador

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Vicente Tinoco

2016-03-01

Full Text Available Study focus: An irrigation project is planned in the study basin for developing the agriculture as the main income in the region. The proposed water system comprises three large reservoirs damming the rivers Macul and Maculillo. The river basin planning and operation were investigated by modelling alternative reservoir operation strategies aiming at a sustainable balance between irrigation and river ecology by integrated reservoir/river management. New hydrological insights for the region: After simulation of long-term meteorological series in a model of the integrated water system, covering several historical extreme events, results indicate that the planned irrigation volumes are higher than the available water for a sustainable irrigation strategy. Two lines of action are suggested for reaching the target irrigation demands: design of a deficit irrigation system, and modifications to the reservoir's spillway height. Keywords: Reservoir operation, Conceptual model, Irrigation

A Reevaluation of Price Elasticities for Irrigation Water

Science.gov (United States)

Howitt, Richard E.; Watson, William D.; Adams, Richard M.

1980-08-01

The effectiveness of pricing systems in the allocation of irrigation water is linked with the price elasticity of demand of farmers for water. Using microeconomic theory, it is shown that omission of the elasticity of demand for the crop produced leads to an inelastic bias in the demand for irrigated water. Linear programing approaches omit the product elasticity of demand and are consequently biased, whereas quadratic programing approaches to estimating derived demands for irrigation water include product demand functions. The difference between the resulting estimates are empirically demonstrated for regional derived demand functions estimated from a model of California's agricultural industry.

Simulated evapotranspiration from a landfill irrigated with landfill leachate

International Nuclear Information System (INIS)

Aronsson, P.

1996-01-01

Evapotranspiration from a landfill area, irrigated with leachate water, was simulated with the SOIL model. Three different types of vegetation (bare soil, grass ley, and willow) were used both with and without irrigation. The highest simulated evapotranspiration (604 mm) during the growing season was found from an irrigated willow stand with a high interception capacity. The lowest evapotranspiration (164 mm) was found from the bare soil. The relatively high evapotranspiration from the willow was probably caused by the high LAI (Leaf Area Index) and the low aerodynamic resistance within the willow stand. The results indicate that it is possible to reduce most of the leakage water from a landfill by irrigation of willow stands. 9 refs, 4 figs, 1 tab

A review of mechanical move sprinkler irrigation control and automation technologies

Science.gov (United States)

Electronic sensors, equipment controls, and communication protocols have been developed to meet the growing interest in site-specific irrigation using center pivot and lateral move irrigation systems. Onboard and field-distributed sensors can collect data necessary for real-time irrigation manageme...

The success of a policy model: Irrigation management transfer in Mexico

NARCIS (Netherlands)

Rap, E.R.

2004-01-01

This thesis studies the emergence, process and outcomes of the Mexican policy of Irrigation Management Transfer (IMT). Under the influence of neo-liberal government policies, the transfer of government-managed irrigation districts to water users' associations (WUAs) has radically changed irrigation

Crop yield response to deficit irrigation imposed at different plant growth stages

International Nuclear Information System (INIS)

Kovaks, T.; Kovaks, G.; Szito, J.

1995-01-01

A series of field experiments were conducted between 1991 - 1994 using 7 irrigation treatments at two fertilizer levels. Nitrogen fertilizers used were labelled with 15 N stable isotope to examine the effect of irrigation on the fertilizer N use efficiency by isotope technique. The irrigation were maintained at four different growth stages of maize, soybean and potato( vegetative, flowering, yield formation and ripening ) in 4 replicates. The aim of study was to compare deficit irrigation( i.e. the water stress imposed, during one growth stage ) with normal irrigation practice included the traditional one. Two watering regimes were established : (1) normal watering when available water was within the range of 60 - 90 %, and (2) deficit irrigation, when the AW was at 30 to 60 %. Neutron probe was used for measuring the soil water status and evaporation data were recorded to determine the amount of irrigation water demand. Reference evapotranspiration ( ETo) was calculated according to Penman - Monteith. Crop water requirement ( ETm) were determined in every year. Actual evapotranspiration ( ETa) was computed using CROPWAT: FAO computer program for irrigation planning and management (1992). Every irrigation treatment was equipped with neutron access tubes in two replicates at a depth from 10 to 130 cm. tensiometers were installed at depths of 30, 50, 60 and 80 cm in one replicate of treatments and were measured on a daily basis while neutron probe measurements were used to monitor the soil water table fluctuations. The irrigation method used was a special type of low pressure drop irrigation. There were measured the amount of rainfall with irrigation water supplied and the moisture distribution profiles were drown for the different treatments. Relationships between relative yield decrease and evapotranspiration and also between the crop yield and water use were determined. 9 tabs, 9 refs, ( Author )

Behavioural modelling of irrigation decision making under water scarcity

Science.gov (United States)

Foster, T.; Brozovic, N.; Butler, A. P.

2013-12-01

Providing effective policy solutions to aquifer depletion caused by abstraction for irrigation is a key challenge for socio-hydrology. However, most crop production functions used in hydrological models do not capture the intraseasonal nature of irrigation planning, or the importance of well yield in land and water use decisions. Here we develop a method for determining stochastic intraseasonal water use that is based on observed farmer behaviour but is also theoretically consistent with dynamically optimal decision making. We use the model to (i) analyse the joint land and water use decision by farmers; (ii) to assess changes in behaviour and production risk in response to water scarcity; and (iii) to understand the limits of applicability of current methods in policy design. We develop a biophysical model of water-limited crop yield building on the AquaCrop model. The model is calibrated and applied to case studies of irrigated corn production in Nebraska and Texas. We run the model iteratively, using long-term climate records, to define two formulations of the crop-water production function: (i) the aggregate relationship between total seasonal irrigation and yield (typical of current approaches); and (ii) the stochastic response of yield and total seasonal irrigation to the choice of an intraseasonal soil moisture target and irrigated area. Irrigated area (the extensive margin decision) and per-area irrigation intensity (the intensive margin decision) are then calculated for different seasonal water restrictions (corresponding to regulatory policies) and well yield constraints on intraseasonal abstraction rates (corresponding to aquifer system limits). Profit- and utility-maximising decisions are determined assuming risk neutrality and varying degrees of risk aversion, respectively. Our results demonstrate that the formulation of the production function has a significant impact on the response to water scarcity. For low well yields, which are the major concern

Maximizing the value of limited irrigation water: USDA researchers study how producers on limited irrigation can save water and be profitable

Science.gov (United States)

Water shortages are responsible for the greatest crop losses around the world and are expected to worsen. In arid areas where agriculture is dependent on irrigation, various forms of deficit irrigation management have been suggested to optimize crop yields for available soil water. The relationshi...

Status and migration of irrigation in the USA

Science.gov (United States)

Irrigated agriculture produces 49% of crop market value on 18% of cropped lands in the USA. Irrigation is essential to the most highly productive, intensely managed, and internationally competitive sectors of our agricultural economy, which play a key role in meeting growing global food, fiber, and ...

Alfalfa response to irrigation from limited water supplies

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A five-year field study (2007-2011) of irrigated alfalfa production with a limited water supply was conducted in southwest Kansas with two years of above-average precipitation, one year of average precipitation, and two years of below-average precipitation. The irrigation treatments were designed to...

[Runoff Pollution Experiments of Paddy Fields Under Different Irrigation Patterns].

Science.gov (United States)

Zhou, Jing-wen; Su, Bao-lin; Huang, Ning-bo; Guan, Yu-tang; Zhao, Kun

2016-03-15

To study runoff and non-point source pollution of paddy fields and to provide a scientific basis for agricultural water management of paddy fields, paddy plots in the Jintan City and the Liyang City were chosen for experiments on non-point source pollution, and flood irrigation and intermittent irrigation patterns were adopted in this research. The surface water level and rainfall were observed during the growing season of paddies, and the runoff amount from paddy plots and loads of total nitrogen (TN) and total phosphorus (TP) were calculated by different methods. The results showed that only five rain events of totally 27 rainfalls and one artificially drainage formed non-point source pollution from flood irrigated paddy plot, which resulted in a TN export coefficient of 49.4 kg · hm⁻² and a TP export coefficient of 1.0 kg · hm⁻². No any runoff event occurred from the paddy plot with intermittent irrigation even in the case of maximum rainfall of 95.1 mm. Runoff from paddy fields was affected by water demands of paddies and irrigation or drainage management, which was directly correlated to surface water level, rainfall amount and the lowest ridge height of outlets. Compared with the flood irrigation, intermittent irrigation could significantly reduce non-point source pollution caused by rainfall or artificial drainage.

Determinants of farmers' participation in collective maintenance of irrigation infrastructure in KwaZulu-Natal

Science.gov (United States)

Sharaunga, S.; Mudhara, M.

2018-06-01

The decentralization framework and the Dublin Principles on Integrated Water Resource Management (IWRM) emphasize the need for a participatory approach to irrigation water management. This study identifies the factors influencing farmers' decision to, and extent of participation in the maintenance of irrigation infrastructure in KwaZulu-Natal province, South Africa based on cross-section data collected from 320 randomly selected smallholder irrigating farmers. A two-step Heckman regression model was applied in the analysis. It was established that households whose heads were older, block committee members, with larger irrigation plots, good soil quality and experiencing severe irrigation water shortages are more likely to participate in maintenance of irrigation infrastructure. On the other hand, farmers with insecure land tenure and with no access to irrigation water were less likely to make the decision to participate. Farmers who were members of the farming cooperative as well as block committee members and those paying irrigation water costs were likely to intensively participate in maintaining irrigation infrastructure. Therefore, decentralization alone cannot lead to improved irrigation outcomes. Several factors are necessary for households to participate intensively in the maintenance of irrigation infrastructure. Governments should address these challenges before handing irrigation schemes to their beneficiaries.

On the use of stochastic approximation Monte Carlo for Monte Carlo integration

KAUST Repository

Liang, Faming

2009-03-01

The stochastic approximation Monte Carlo (SAMC) algorithm has recently been proposed as a dynamic optimization algorithm in the literature. In this paper, we show in theory that the samples generated by SAMC can be used for Monte Carlo integration via a dynamically weighted estimator by calling some results from the literature of nonhomogeneous Markov chains. Our numerical results indicate that SAMC can yield significant savings over conventional Monte Carlo algorithms, such as the Metropolis-Hastings algorithm, for the problems for which the energy landscape is rugged. © 2008 Elsevier B.V. All rights reserved.

On the use of stochastic approximation Monte Carlo for Monte Carlo integration

KAUST Repository

Liang, Faming

2009-01-01

The stochastic approximation Monte Carlo (SAMC) algorithm has recently been proposed as a dynamic optimization algorithm in the literature. In this paper, we show in theory that the samples generated by SAMC can be used for Monte Carlo integration

Influencing Factors and Simplified Model of Film Hole Irrigation

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Yi-Bo Li

2017-07-01

Full Text Available Film hole irrigation is an advanced low-cost and high-efficiency irrigation method, which can improve water conservation and water use efficiency. Given its various advantages and potential applications, we conducted a laboratory study to investigate the effects of soil texture, bulk density, initial soil moisture, irrigation depth, opening ratio (ρ, film hole diameter (D, and spacing on cumulative infiltration using SWMS-2D. We then proposed a simplified model based on the Kostiakov model for infiltration estimation. Error analyses indicated SWMS-2D to be suitable for infiltration simulation of film hole irrigation. Additional SWMS-2D-based investigations indicated that, for a certain soil, initial soil moisture and irrigation depth had the weakest effects on cumulative infiltration, whereas ρ and D had the strongest effects on cumulative infiltration. A simplified model with ρ and D was further established, and its use was then expanded to different soils. Verification based on seven soil types indicated that the established simplified double-factor model effectively estimates cumulative infiltration for film hole irrigation, with a small mean average error of 0.141–2.299 mm, a root mean square error of 0.177–2.722 mm, a percent bias of −2.131–1.479%, and a large Nash–Sutcliffe coefficient that is close to 1.0.

Coastal surface water suitability analysis for irrigation in Bangladesh

Science.gov (United States)

Mahtab, Mohammad Hossain; Zahid, Anwar

2018-03-01

Water with adequate quality and quantity is very important for irrigation to ensure the crop yields. Salinity is common problem in the coastal waters in Bangladesh. The intensity of salinity in the coastal zone in Bangladesh is not same. It fluctuates over the year. Sodium is another hazard which may hamper permeability and ultimately affects the fertility. It can reduce the crop yields. Although surface water is available in the coastal zone of Bangladesh, but its quality for irrigation needs to be monitored over the year. This paper will investigate the overall quality of coastal surface waters. Thirty-three water samples from different rivers were collected both in wet period (October-December) and in dry period (February-April). Different physical and chemical parameters are considered for investigation of the adequacy of water with respect to international irrigation water quality standards and Bangladesh standards. A comparison between the dry and wet period coastal surface water quality in Bangladesh will also be drawn here. The analysis shows that coastal surface water in Bangladesh is overall suitable for irrigation during wet period, while it needs treatment (which will increase the irrigation cost) for using for irrigation during dry period. Adaptation to this situation can improve the scenario. An integrated plan should be taken to increase the water storing capacity in the coastal area to harvest water during wet period.

Conserving energy through new irrigation technologies. Technical briefing report

Energy Technology Data Exchange (ETDEWEB)

1982-07-01

The benefits and applications of five irrigation technologies are explored: mobile drop-tube irrigation, computerized scheduling, reduced-pressure center pivots, well design and development, and automated gated-pipe systems. Perhaps the most promising of the new irrigation technologies is the low-energy, precision-application (LEPA) system. This mobile system used one-half the energy of conventional sprinkler systems and distributes water with greater efficiency through a series of low-pressure drop tubes suspended above the crop. Computerized methods of irrigation scheduling have been developed to help farmers conserve water and energy. Special computer programs determine when a crop needs water and how much to apply for optimal plant growth, thus preventing the unnecessary costs of pumping more water than the crop needs. Field test results show that replacing traditional scheduling methods of irrigation with computerized scheduling can reduce energy and water use by as much as 35%. The irrigation industry is actively promoting reduced-pressure water application methods, particularly for center-pivot systems. Reduced-pressure systems expend less energy but produce the same crop yields as conventional high-pressure systems, as long as excessive water runoff does not occur. If well design and development techniques are applied when a well is drilled into an unconsolidated acquifer, the well's life expectancy, as well as its operating efficiency, can increase, the later by as much as 40%.

78 FR 53243 - Safety Zone; TriRock San Diego, San Diego Bay, San Diego, CA

Science.gov (United States)

2013-08-29

... this rule because the logistical details of the San Diego Bay triathlon swim were not finalized nor... September 22, 2013. (c) Definitions. The following definition applies to this section: Designated...

Irrigation as an Adaptation Strategy to Climate Change: The Relative Influence of Groundwater and Canal Irrigation on Winter Crop Production and its Sensitivity to Weather Variability in India

Science.gov (United States)

Jain, M.; Fishman, R.; Mondal, P.; Galford, G. L.; Naeem, S.; Modi, V.; DeFries, R. S.

2014-12-01

India is a hotspot for food security issues over the upcoming decades, due to increasing population pressures, groundwater depletion, and climate change. Investing in additional irrigation infrastructure may bolster food security, however, the relative influence of different types of irrigation (e.g. groundwater versus canal) on agricultural production remains unclear. One reason that the relative impact of different irrigation strategies on agricultural production has not been analyzed across India is because national-scale data on crop production and the types of irrigation technologies used are typically available at too coarse of spatial and temporal resolutions to answer this question adequately. Thus, we develop a novel algorithm to map cropped area across India at a 1 x 1 km scale using MODIS satellite data, and link these high-resolution cropped area maps with village-level data (n = 600,000) on irrigation. This allowed us to assess the relative impact of groundwater (i.e. dug, shallow, and deep wells) and canal irrigation (i.e. surface lift and flow canals) on winter cropped area and its sensitivity to rainfall across India at the village-scale from 2000 to 2006. We find that deep well irrigation is both associated with the greatest amount of winter cropped area, and is also the least sensitive to monsoon and winter rainfall variability. However, the effectiveness of deep well irrigation varies across India, with the greatest benefits seen in the regions that are most at risk for losing groundwater as a possible source of irrigation over the upcoming decades (e.g. Northwest India). This work highlights the need to develop ways to use remaining groundwater more efficiently (e.g. drip irrigation, less water-intensive crops) given that canal irrigation is not an adequate substitute, particularly in the regions that are facing the greatest levels of groundwater depletion.

AGROCLIMATIC DETERMINANTS OF IRRIGATION NEEDS

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Leszek Łabędzki

2016-05-01

Full Text Available The paper is a review of the so far used in Poland methods and criteria for assessing the needs of irrigation for planning purposes, the assessment because of the agroclimatic conditions and taking into account the soil water retention. Irrigation needs of the most are determined taking into account crop water deficits. This is the factor that is characterized by a shortage of precipitation in relation to the water requirements of crops. Some methods use only the meteorological parameters that determine the state of the atmosphere-soil-plant system, and some also take into account soil water retention and its availability for plants.

Mapping irrigated areas in Afghanistan over the past decade using MODIS NDVI

Science.gov (United States)

Pervez, Md Shahriar; Budde, Michael; Rowland, James

2014-01-01

Agricultural production capacity contributes to food security in Afghanistan and is largely dependent on irrigated farming, mostly utilizing surface water fed by snowmelt. Because of the high contribution of irrigated crops (> 80%) to total agricultural production, knowing the spatial distribution and year-to-year variability in irrigated areas is imperative to monitoring food security for the country. We used 16-day composites of the Normalized Difference Vegetation Index (NDVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor to create 23-point time series for each year from 2000 through 2013. Seasonal peak values and time series were used in a threshold-dependent decision tree algorithm to map irrigated areas in Afghanistan for the last 14 years. In the absence of ground reference irrigated area information, we evaluated these maps with the irrigated areas classified from multiple snapshots of the landscape during the growing season from Landsat 5 optical and thermal sensor images. We were able to identify irrigated areas using Landsat imagery by selecting as irrigated those areas with Landsat-derived NDVI greater than 0.30–0.45, depending on the date of the Landsat image and surface temperature less than or equal to 310 Kelvin (36.9 ° C). Due to the availability of Landsat images, we were able to compare with the MODIS-derived maps for four years: 2000, 2009, 2010, and 2011. The irrigated areas derived from Landsat agreed well r2 = 0.91 with the irrigated areas derived from MODIS, providing confidence in the MODIS NDVI threshold approach. The maps portrayed a highly dynamic irrigated agriculture practice in Afghanistan, where the amount of irrigated area was largely determined by the availability of surface water, especially snowmelt, and varied by as much as 30% between water surplus and water deficit years. During the past 14 years, 2001, 2004, and 2008 showed the lowest levels of irrigated area (~ 1.5 million hectares), attesting to

Production of mungbean under reclaimed sandy soil and irrigation levels using N-15 labeled

International Nuclear Information System (INIS)

Abdallah, A.A.G.; Thabet, E.M.A.

2000-01-01

Field experiment were performed at the Atomic Energy Authority, Experimental farm, Inshas, Egypt. During 1998 growing season. In tafla and sand mixture soil (1:7 Wt./Wt.). The treatments were laid out using a single line source sprinkler irrigation system which allows a gradual variation of irrigation from excess to little irrigation in which the calculated amount of irrigation water levels were 2241, 1562 and 1093 m 3 / feddan (W 1 , W 2 and W 3 ). The obtained results indicated that, there was a clear relationship between adequate amount of irrigation water and both total seed yield and total green pods/plot as well as there were significant increase in both characters due to irrigation W 1 and W 2 compared with W 3 . The results also indicated that W 2 irrigation level could be used in irrigation under the same conditions. Water use efficiency was significantly increased with middle irrigation level than with other two irrigation treatments. The result concerned fertilizer use efficiency using N 15 labeled fertilizers and total seed protein content were increased with decreasing irrigation level

System contemplations for precision irrigation in agriculture

Science.gov (United States)

Schubert, Martin J. W.

2017-04-01

This communication contemplates political, biological and technical aspects for efficient and profitable irrigation in sustainable agriculture. A standard for irrigation components is proposed. The need for many, and three-dimensionally distributed, soil measurement points is explained, thus enabling the control of humidity in selected layers of earth. Combined wireless and wired data transmission is proposed. Energy harvesting and storage together with mechanical sensor construction are discussed.

Temperature-controlled irrigated tip radiofrequency catheter ablation

DEFF Research Database (Denmark)

Petersen, H H; Chen, X; Pietersen, Adrian

1998-01-01

INTRODUCTION: In patients with ventricular tachycardias due to structural heart disease, catheter ablation cures radiofrequency ablation. Irrigated tip radiofrequency ablation using power control and high infusion rates enlarges lesion......: We conclude that temperature-controlled radiofrequency ablation with irrigated tip catheters using low target temperature and low infusion rate enlarges lesion size without increasing the incidence of cratering and reduces coagulum formation of the tip....

The maximum economic depth of groundwater abstraction for irrigation

Science.gov (United States)

Bierkens, M. F.; Van Beek, L. P.; de Graaf, I. E. M.; Gleeson, T. P.

2017-12-01

Over recent decades, groundwater has become increasingly important for agriculture. Irrigation accounts for 40% of the global food production and its importance is expected to grow further in the near future. Already, about 70% of the globally abstracted water is used for irrigation, and nearly half of that is pumped groundwater. In many irrigated areas where groundwater is the primary source of irrigation water, groundwater abstraction is larger than recharge and we see massive groundwater head decline in these areas. An important question then is: to what maximum depth can groundwater be pumped for it to be still economically recoverable? The objective of this study is therefore to create a global map of the maximum depth of economically recoverable groundwater when used for irrigation. The maximum economic depth is the maximum depth at which revenues are still larger than pumping costs or the maximum depth at which initial investments become too large compared to yearly revenues. To this end we set up a simple economic model where costs of well drilling and the energy costs of pumping, which are a function of well depth and static head depth respectively, are compared with the revenues obtained for the irrigated crops. Parameters for the cost sub-model are obtained from several US-based studies and applied to other countries based on GDP/capita as an index of labour costs. The revenue sub-model is based on gross irrigation water demand calculated with a global hydrological and water resources model, areal coverage of crop types from MIRCA2000 and FAO-based statistics on crop yield and market price. We applied our method to irrigated areas in the world overlying productive aquifers. Estimated maximum economic depths range between 50 and 500 m. Most important factors explaining the maximum economic depth are the dominant crop type in the area and whether or not initial investments in well infrastructure are limiting. In subsequent research, our estimates of

Irrigated Area Maps and Statistics of India Using Remote Sensing and National Statistics

Directory of Open Access Journals (Sweden)

Prasad S. Thenkabail

2009-04-01

Full Text Available The goal of this research was to compare the remote-sensing derived irrigated areas with census-derived statistics reported in the national system. India, which has nearly 30% of global annualized irrigated areas (AIAs, and is the leading irrigated area country in the World, along with China, was chosen for the study. Irrigated areas were derived for nominal year 2000 using time-series remote sensing at two spatial resolutions: (a 10-km Advanced Very High Resolution Radiometer (AVHRR and (b 500-m Moderate Resolution Imaging Spectroradiometer (MODIS. These areas were compared with the Indian National Statistical Data on irrigated areas reported by the: (a Directorate of Economics and Statistics (DES of the Ministry of Agriculture (MOA, and (b Ministry of Water Resources (MoWR. A state-by-state comparison of remote sensing derived irrigated areas when compared with MoWR derived irrigation potential utilized (IPU, an equivalent of AIA, provided a high degree of correlation with R2 values of: (a 0.79 with 10-km, and (b 0.85 with MODIS 500-m. However, the remote sensing derived irrigated area estimates for India were consistently higher than the irrigated areas reported by the national statistics. The remote sensing derived total area available for irrigation (TAAI, which does not consider intensity of irrigation, was 101 million hectares (Mha using 10-km and 113 Mha using 500-m. The AIAs, which considers intensity of irrigation, was 132 Mha using 10-km and 146 Mha using 500-m. In contrast the IPU, an equivalent of AIAs, as reported by MoWR was 83 Mha. There are “large variations” in irrigated area statistics reported, even between two ministries (e.g., Directorate of Statistics of Ministry of Agriculture and Ministry of Water Resources of the same national system. The causes include: (a reluctance on part of the states to furnish irrigated area data in view of their vested interests in sharing of water, and (b reporting of large volumes of data

The fluid mechanics of root canal irrigation.

Science.gov (United States)

Gulabivala, K; Ng, Y-L; Gilbertson, M; Eames, I

2010-12-01

Root canal treatment is a common dental operation aimed at removing the contents of the geometrically complex canal chambers within teeth; its purpose is to remove diseased or infected tissue. The complex chamber is first enlarged and shaped by instruments to a size sufficient to deliver antibacterial fluids. These irrigants help to dissolve dying tissue, disinfect the canal walls and space and flush out debris. The effectiveness of the procedure is limited by access to the canal terminus. Endodontic research is focused on finding the instruments and clinical procedures that might improve success rates by more effectively reaching the apical anatomy. The individual factors affecting treatment outcome have not been unequivocally deciphered, partly because of the difficulty in isolating them and in making the link between simplified, general experimental models and the complex biological objects that are teeth. Explicitly considering the physical processes within the root canal can contribute to the resolution of these problems. The central problem is one of fluid motion in a confined geometry, which makes the dispersion and mixing of irrigant more difficult because of the absence of turbulence over much of the canal volume. The effects of treatments can be understood through the use of scale models, mathematical modelling and numerical computations. A particular concern in treatment is that caustic irrigant may penetrate beyond the root canal, causing chemical damage to the jawbone. In fact, a stagnation plane exists beyond the needle tip, which the irrigant cannot penetrate. The goal is therefore to shift the stagnation plane apically to be coincident with the canal terminus without extending beyond it. Needle design may solve some of the problems but the best design for irrigant penetration conflicts with that for optimal removal of the bacterial biofilm from the canal wall. Both irrigant penetration and biofilm removal may be improved through canal fluid

The fluid mechanics of root canal irrigation

International Nuclear Information System (INIS)

Gulabivala, K; Ng, Y-L; Gilbertson, M; Eames, I

2010-01-01

Root canal treatment is a common dental operation aimed at removing the contents of the geometrically complex canal chambers within teeth; its purpose is to remove diseased or infected tissue. The complex chamber is first enlarged and shaped by instruments to a size sufficient to deliver antibacterial fluids. These irrigants help to dissolve dying tissue, disinfect the canal walls and space and flush out debris. The effectiveness of the procedure is limited by access to the canal terminus. Endodontic research is focused on finding the instruments and clinical procedures that might improve success rates by more effectively reaching the apical anatomy. The individual factors affecting treatment outcome have not been unequivocally deciphered, partly because of the difficulty in isolating them and in making the link between simplified, general experimental models and the complex biological objects that are teeth. Explicitly considering the physical processes within the root canal can contribute to the resolution of these problems. The central problem is one of fluid motion in a confined geometry, which makes the dispersion and mixing of irrigant more difficult because of the absence of turbulence over much of the canal volume. The effects of treatments can be understood through the use of scale models, mathematical modelling and numerical computations. A particular concern in treatment is that caustic irrigant may penetrate beyond the root canal, causing chemical damage to the jawbone. In fact, a stagnation plane exists beyond the needle tip, which the irrigant cannot penetrate. The goal is therefore to shift the stagnation plane apically to be coincident with the canal terminus without extending beyond it. Needle design may solve some of the problems but the best design for irrigant penetration conflicts with that for optimal removal of the bacterial biofilm from the canal wall. Both irrigant penetration and biofilm removal may be improved through canal fluid

Consumption and cost of diesel oil on cultivation of Zoysiagrass (Zoysia japonica Steud.) irrigated by aspersion canyons under two irrigation handlings

Energy Technology Data Exchange (ETDEWEB)

Mazaroni, Bruno Henrique Silveira; Turco, Jose Eduardo Pitelli; Coan, Ruchele Marchiori; Gerolineto, Eduardo [Universidade Estadual Paulista (FCAV/UNESP), Jaboticabal, SP (Brazil). Fac. de Ciencias Agrarias e Veterinarias

2008-07-01

This work aim to analyse the consumption and cost of diesel oil on cultivation of zoysiagrass (Zoysia japonica Steud.) irrigated by aspersion canyon, submitted of to two irrigation handling: T1 - irrigated when the tensiometer reading is equal - 0,5 atmospheres and T2 - irrigated by grass growers methodology. The research was carried on Green-Park Farm, in the city of Pitangueiras, SP. Consumption of diesel oil was measured from a diesel engine, brand MWM, turbined with 6 cylinders, type D-229 for zoysiagrass production. The diesel price was gotten from Petroleum National Agency (ANP), being an average price in Sao Paulo State, in February 2007, converted into the commercial dollar. Economical result was studied, subtracting the selling value of the grass, by the cost of the fuel consumed, for both T1 and T2 treatments. The treatment made by tensiometer showed greater diesel consumption, related to treatment T2, where the handling was made by the grass grower. (author)

Irrigation in the Lower Durance: positive impacts of the agriculture

International Nuclear Information System (INIS)

Lacroix, M.; Blavoux, B.

1995-01-01

The water of river Durance is used to produce hydroelectricity and as stretch of water for tourism and since the thirteenth century for irrigation. The inherited situation is a well extended network of gravitation irrigation canals. This system is spendthrift of water, the water supplies are roughly 5 times the farming needs. The impact of this irrigation on the alluvial aquifer of the Lower Durance is the generalisation of the highest level of the water table in summer on the plain though the water budget has an average deficit of 550 mm. In addition, the nitrate concentration is maintained to an average of 17 mg/l in groundwater and 5 mg/l in streams by dilution. In fact, the irrigation dictates an average input of water with 25.4 mg/l of NO 3- . The natural isotopic tracing (oxygen 18) allows to say that 50 to 75% of the water of the alluvial aquifer come from irrigation. To improve the knowledge about the efficiency of irrigation, a mathematical groundwater model has been created. As a result, 53% of the water is lost while reaching the agricultural parcels, 19% is infiltrated during watering at the parcel and only 28% are used to satisfy the needs of plants. The realisation of this model has allowed to simulate the impact on groundwater of changes in irrigation practices which would lead to reduce the consummation of water. In the case of Lower Durance, the reduction of irrigation losses would have a strong impact on the quantity and quality of water in the alluvial aquifer. (J.S.). 10 refs., 9 figs., 2 tabs

Heavy-metal contamination of agricultural soils irrigated with industrial effluents

International Nuclear Information System (INIS)

Nabi, G.; Ashraf, M.; Aslam, M. R.

2001-01-01

Pakistan is facing a thread of degradation of water and land-resources by industrial effluents. To evaluated the suitability of these effluents as a source of irrigation for agriculture and the study their effects on soil chemical properties, experiments were conducted in the industrial area of Sheikhupura, where effluent from Paper and Board Mill (PBM), Leather Industry (LI) and Fertilizer Industry (FI) were being used for irrigation. At each site, two fields were selected, one irrigated with industrial effluents and the other with tube-well/canal water. The soil samples were collected and analyzed for pH, ECe, SAR and for heavy metals, such as Cu, Cd, Cr, Zn, Pb, Mn, Fe, Al and Ni. Soil receiving effluent from LI showed higher ECe and SAR values, as compared to the soils receiving other effluents. The concentration of Al was high in the soil irrigated with LI effluent. The Mn and Fe contents were higher in soils irrigated with PBM effluent. Effluent from LI is not fit for irrigation, since its recipient soil showed high concentration of Cr and also high sodicity values. Except Cr, the heavy metals were not of environmental concern. (author)

77 FR 59969 - Notice of Inventory Completion: San Francisco State University, Department of Anthropology, San...

Science.gov (United States)

2012-10-01

... Inventory Completion: San Francisco State University, Department of Anthropology, San Francisco, CA... Francisco State University, NAGPRA Program (formerly in the Department of Anthropology). The human remains... State University Department of Anthropology records. In the Federal Register (73 FR 30156-30158, May 23...

Coil irrigation in sugar cane (Saccharum officinarum

Directory of Open Access Journals (Sweden)

Jesús Sánchez Gutiérrez

2016-01-01

Full Text Available This study was made at the Basic Seed Bank of the Local Sugar Cane Research Station for the Mideastern Cuba, based in Camaguey, on brown carbonate soil, between 2013 and 12014. Coil irrigation was applied to meet the water requirements for the crop, according to the edafoclimatic conditions and the different phenological phases it has. The Savo method was used to determine useful rain water. Adjustment and complementation of the irrigation program was based on indicators that characterize the exploitation scheme. The machine´s working parameters were determined to meet the water needs, and increase crop´s overall yields. The evaluations and results achieved have contributed to new proposals for management and operation of coil irrigation, and they are important to increase its efficiency.

The Reticulation Irrigation Scheme at Sankana, Upper West Region ...

African Journals Online (AJOL)

farmers utilizing the irrigation project are food secure. ... The effects of ... Often, lack of maintenance, bad management and financial difficulties decrease the ...... and Mushunje A. (2010), 'Analysis of Irrigation Development Post Fast Track Land ...

Impact of upstream industrial effluents on irrigation water quality ...

African Journals Online (AJOL)

Impact of upstream industrial effluents on irrigation water quality, soils and ... Knowledge of irrigation water quality is critical to predicting, managing and reducing salt ... Presence of heavy metals in concentration higher than the recommended ...