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El cultivo de alfalfa utilizando agua de perforación, agua residual urbana y precipitaciones Texte intégral
2012
Plevich, José O.(Universidad Nacional de Río Cuarto Depto de Producción Vegetal) | Delgado, Angel R. S.(PPGCTIA UFRRJ) | Saroff, Cecilia(Universidad Nacional de Río Cuarto Depto de Producción Vegetal) | Tarico, Juan C.(Universidad Nacional de Río Cuarto Depto de Producción Vegetal) | Crespi, R. J.(Universidad Nacional de Río Cuarto Depto de Ecologia Agrícola) | Barotto, Omar M.(Universidad Nacional de Río Cuarto Depto de Producción Vegetal)
The objective of this study was to analyse the production of alfalfa biomass, the efficiency of water use and the nutritional value of forage, inside an irrigation structure of an experimental facility that uses treated urban wastewater, artesian well water and rainfall, at the campus of the Universidad National de Rio Cuarto (Córdoba-Argentina). The irrigation treatment had a positive effect on the production of biomass of alfalfa. On an average 24% increase in production was observed when compared to dry-land farming. Regarding the quality of the irrigation water, statistical differences in production were observed, the irrigation with urban wastewater produced 19% more than that of well water. The efficiency of the water use by the crop increased when the irrigation was done using urban wastewater. The alfalfa irrigated with wastewater surpasses the nutritional values of the crop in normal field conditions: 39% more proteins, 14% more digestibility and equal percentage of metabolic energy. It is concluded that the urban wastewater represents possible water source for the alfalfa crop. | El objetivo de este trabajo fue analizar la producción de biomasa aérea, la eficiencia del uso de agua y el valor nutritivo de alfalfa cultivada aplicando riego con agua residual urbana, agua de perforación y un testigo (precipitaciones), en el Campus de la Universidad Nacional de Rio Cuarto (Córdoba-Argentina). Los tratamientos de riego tuvieron un efecto positivo sobre la producción de biomasa aérea obteniéndose un 24% más de producción de biomasa que en la situación de secano (precipitaciones). Entre los tratamientos con riego también se manifestaron diferencias estadísticamente significativas. La alfalfa regada con aguas residuales urbana supero en un 19% a la cultivada con agua de perforación. La eficiencia del uso del agua por parte del cultivo se incrementó cuando el riego se realizó con aguas residuales urbanas. Además, se determinó que la alfalfa regada con agua residual, supera los valores nutritivos del cultivo que crece en condiciones sin riego; encontrándose 39% más de proteínas, 14% más de digestibilidad e igual porcentaje de energía metabólica. Se puede concluir que el agua residual urbana representa otra posible fuente de agua, factible de ingresar al suelo y estar a disposición para el cultivo de alfalfa.
Afficher plus [+] Moins [-]Diseño y caracterización de hidrogeles empleando Eichhornia crassipes (buchón de agua) | Design and characterization of hydrogels using Eichhornia crassipes (water hyacinth) Texte intégral
2024
Briceño Barón, Andrea Nicole | Molina Rodríguez, Angelly Nicole | Quiñones Martinez, Maria Jose | Jiménez Cruz, Ronald Andrés | Millán Cortés, Diana Milena
La creciente demanda de alternativas a los hidrogeles sintéticos y la inconveniente proliferación de la Eichhornia crassipes que causa afectaciones al medio ambiente, parecen ser dos problemáticas que se pueden solventar entre sí. Este estudio pretendía evaluar la viabilidad de esta planta invasora como fuente de celulosa para la fabricación de hidrogeles físicos de uso tópico. Para ello, se obtuvieron cuatro prototipos mediante variaciones de la metodología Organosolv, los cuales fueron caracterizados farmacotécnicamente y reológicamente. Los ensayos revelaron que cada prototipo obtenido se trataba de un hidrogel, con un contenido de agua superior al 92%, determinado por pérdida por secado, y un rendimiento del 31.1% ± 4.9%. La esparcibilidad señaló el prototipo B como semifluido, mientras que las pruebas reológicas determinaron que entre los prototipos no hay diferencias significativas y son pseudoplásticos garantizando el uso como hidrogeles tópicos. Además, todos los hidrogeles demostraron una baja citotoxicidad. Un análisis IR sugirió diferencias estructurales en cada uno de los hidrogeles, confirmando a su vez la prevalencia de celulosa. Se llevó a cabo un análisis de varianza (p < 0.05) para determinar cambios significativos. En conjunto, estos hallazgos sugieren que la Eichhornia crassipes es una fuente viable para la fabricación de hidrogeles. | Pregrado | Químico Farmacéutico | The increasing demand for alternatives to synthetic hydrogels and the issue of Eichhornia crassipes' proliferation, which causes environmental damage, seem to be two problems that can be addressed by each other. This study aimed to evaluate the feasibility of utilizing this invasive plant as a source of cellulose for the fabrication of topical-use physical hydrogels. Four prototypes were synthesized via variations of the Organosolv methodology and subsequently subjected to pharmaceutical characterization. The experimental assays demonstrated that each prototype constituted a hydrogel, characterized by a water content exceeding 92%, as determined through drying loss, with a yield of 31.1% ± 4.9%. Evaluation of spreadability indicated the suitability of prototype B, while rheological assessments determined that there were no significant differences among the prototypes and they were all pseudoplastic, enserió their use as topical hydrogels. Furthermore, all hydrogels exhibited low cytotoxicity. Infrared spectroscopy revealed distinctive structural variances among the hydrogel formulations, confirming the predominance of cellulose. Statistical analysis, conducted via analysis of variance (p < 0.05), underscored significant differences. Collectively, these findings display the potential of Eichhornia crassipes as a viable cellulose source for hydrogel production.
Afficher plus [+] Moins [-]Demanda hídrica e eficiência do uso de água da cana-de-açúcar irrigada no semiárido brasileiro Water requirement and efficiency of water use of irrigated sugarcane in semi-arid Brazil Texte intégral
2011
Thieres G. F. da Silva | Magna S. B. de Moura | Sérgio Zolnier | José M. Soares | Vinícius J. de S. Vieira | Walter F. Gomes Júnior
Este trabalho objetivou realizar uma análise da eficiência do uso de água em um sistema de produção de cana-de-açúcar irrigada no Submédio do Vale do São Francisco, Brasil. Indicadores que consideram a resposta produtiva da cultura e o desempenho de aplicação de água no sistema de produção foram utilizados e calculados por meio de dados de biomassa seca acumulada, rendimento industrial e a partir dos valores de evapotranspiração de referência (ETo), evapotranspiração da cultura (ETc) e do volume de água que entrou no sistema de produção por precipitação e irrigação (P + I). Verificou-se que a maior eficiência do uso de água pela cultura ocorreu entre o sétimo e o oitavo meses produtivos em virtude do aumento da partição de biomassa para os colmos e do suprimento de radiação e, ainda, da redução da ETc em resposta ao tombamento das plantas. Os indicadores utilizados demonstraram que a demanda de água da cultura foi suprida adequadamente em relação à evapotranspiração máxima. A cana-de-açúcar apresentou uma eficiência de produção de 9,49 kg de colmos, 1,22 kg de açúcar e 875,23 mL de álcool por m3 de ETc e 5,36 kg de colmos, 0,69 kg de açúcar e 494,14 ml de álcool por m3 de P+I.<br>The objective of this work was to accomplish an analysis of the water use efficiency in a production system of irrigated sugarcane located in the Lower-Middle São Francisco river basin, Brazil. Indicators based on the crop yield and the water application performance in the production system were used. These indicators were calculated through accumulated dry biomass, industrial yield data and through the values of reference evapotranspiration, crop evapotranspiration and the water volume that entered in the system by rain and irrigation (P+I). It was verified that, the highest water use efficiency of crop occured between 7th and 8th month, due to increase in the stalk biomass partition and radiation supply, and due to reduction of ETc in response tumbling of the plants. The used indicators demonstrated that the water demand of crop was adequately in relation to maximum evapotranspiration of crop. The irrigated sugarcane presented a production efficiency of 9.49 kg of stalks, 1.22 kg of sugar and 875.23 mL of alcohol per m3 of ETc and of 5.36 kg of stalks, 0.69 kg of sugar and 494.14 mL of alcohol per m3 of P+I.
Afficher plus [+] Moins [-]Crescimento de jundiá e carpa húngara criados em sistema de recirculação de água Jundiá growth and Common Carp reared in recirculated water system Texte intégral
2009
Viviani Corrêia | João Radünz Neto | Rafael Lazzari | Cátia Aline Veiverberg | Giovani Taffarel Bergamin | Fabio de Araújo Pedron | Cristiano Costenaro Ferreira | Tatiana Emanuelli | Cristiane Portes Ribeiro
O presente estudo foi realizado com o objetivo de comparar o crescimento e o rendimento de carcaça e a composição corporal de juvenis de jundiá (Rhamdia quelen) e carpa húngara (Cyprinus carpio) criados em sistema de recirculação de água, em mono e bicultivo, durante 60 dias, na fase de recria. Cinco tratamentos com três repetições foram testados: 100C=100% carpa; 100J=100% jundiá; 50C50J=50% carpa 50% jundiá; 75C25J=75% carpa 25% jundiá e 25C75J=25% carpa 75% jundiá, sendo utilizados 20 peixes por unidade experimental. Foram avaliados o peso (P), a biomassa total (BT), o fator de condição (FC), a conversão alimentar aparente (CAA), a taxa de crescimento específico (TCE), o rendimento de carcaça (RC), o índice digestivo-somático, o índice hepato-somático, o quociente intestinal, as composições centesimais dos peixes, as taxas de deposição de proteína e a gordura corporal. Não foram observadas diferenças no peso, no FC e na TCE dos jundiás (P>0,05). Para essas variáveis, as carpas submetidas ao tratamento 25C75J apresentaram valores significativamente maiores (P<0,05). O tratamento 100J produziu os melhores valores de CAA e BT e não diferiu do 25C75J. Em ambas as espécies, não houve diferença significativa para RC e índices digestivos. Em bicultivo, a proporção 25% carpa 75% jundiá resulta no maior peso individual das carpas húngaras e na maior biomassa total.<br>A study was conducted to evaluate growth, carcass yield and body composition of jundiá and common carp raised in mono or duoculture in a recirculated water system, for 60 days, during the growing. Five treatments were tested with three replicates: 100C=100% carp; 100J=100% jundiá, 50C50J=50% carp 50% jundiá; 75C25J=75% carp 25% jundiá and 25C75J=25% carp 75% jundiá. Twenty fishes were distributed in each experimental unit. It was evaluated weight (W), total biomass (TB), condition factor (CF), feed conversion rate (FCR), specific growth rate (SGR), carcass yield (YC), digestive-somatic index, hepatossomatic index, intestinal quotient and the proximate composition and body deposition of protein and fat. Considering jundiá performance, no statistical difference was observed for W, CF and SGR (P>0.05). Common carp from treatment 25C75J showed the highest values (P<0.05) for these variables. The best FCR and TB values were obtained for 100J and 25C75J treatments. In both species, there were no differences for carcass yield or digestive indexes. Thus, the treatment 25C75J, composed by 25%carp and 75%jundiá presented the highest final weight for carp and total biomass.
Afficher plus [+] Moins [-][Cuéllar [a village of Segovia province, Spain], central heating and hot water coming from biomass] | Cuéllar, calefacción central y agua caliente procedente de biomasa Texte intégral
2006
Guerrero, M.
Bioenergia procedente del jacinto de agua (Eichhornia crassipes).
1989
Bigeriego M. | Guardiola E. | Delgado M.
Nematode assemblages in four ecosystems of Parque Nacional del Agua, Costa Rica Texte intégral
2022
Varela-Benavides, Ingrid | Abolafia, Joaquín | Guevara-Mora, Meyer | Peña-Santiago, R. (Reyes) | Ferris, Howard
The soil nematode fauna of five locations situated in Parque Nacional del Agua (PNA) in Costa Rica is characterized and analyzed. Four ecosystems were sampled in each location: primary (undisturbed) forest, secondary (naturally regenerated) forests, tree plantations (cleared and replanted with timber trees), and pastures (cleared of trees). Five soil samples of 100 g were analyzed in each location and ecosystem, resulting in a total of 100 samples. One hundred and thirty-one nematode genera were identified, and their abundance and biomass were estimated and analyzed by means of nonmetric multidimensional scaling (NMDS) and redundancy analysis (RDA). The observed nematode abundance was 1237 ± 520 specimens per soil sample for the whole survey, similar to previously reported from tropical soils. Dominance-diversity curves, based on nematode abundance, follow a similar ‘hollow curve’ pattern, with only 20 of the genera representing 84.6% of the total abundance, and only 12 of the genera representing 88% of the total biomass. Helicotylenchus, tylenchids, criconematids, Belondira, Longidorus, Xiphinema, Monotrichodorus, Prismatolaimus and Steinernema are important in the assemblages due their abundance or biomass in the different samples. Monotrichodorus and Discocriconemella appear related to undisturbed ecosystems, and they could have potential as disturbance indicators. Biomass-based dominance-diversity curves have similar qualitative and quantitative behavior to those observed in abundance distribution, but the dorylaims, Aporcelinus and Aporcelaimoides, which represented only the 0.35% of the abundance, having a major part of the total biomass (4.33%). NMDS analysis segregated locations into two groups, sampled sites were arranged according to the life zone where they belong. Ecosystems were segregated into natural ecosystems and plantations but having overlapping zones. Whereas RDA analysis indicated that organic matter and Cu are the most relevant edaphic variables for explaining the distribution of nematode assemblages, however few genera appear important in the ordination, Mesocriconema, Longidorus, Xiphinema and Belondira between them.
Afficher plus [+] Moins [-]O consumo de agua pela floresta no caso do eucalipto em Portugal.
1989
Pereira J.S.
Nematode assemblages in four ecosystems of Parque Nacional del Agua, Costa Rica Texte intégral
2022
Varela-Benavides, Ingrid | Abolafia, Joaquín | Guevara-Mora, Meyer | Peña Santiago, Reyes | Ferris, Howard
The soil nematode fauna of five locations situated in Parque Nacional del Agua (PNA) in Costa Rica is characterized and analyzed. Four ecosystems were sampled in each location: primary (undisturbed) forest, secondary (naturally regenerated) forests, tree plantations (cleared and replanted with timber trees), and pastures (cleared of trees). Five soil samples of 100 g were analyzed in each location and ecosystem, resulting in a total of 100 samples. One hundred and thirty-one nematode genera were identified, and their abundance and biomass were estimated and analyzed by means of nonmetric multidimensional scaling (NMDS) and redundancy analysis (RDA). The observed nematode abundance was 1237 ± 520 specimens per soil sample for the whole survey, similar to previously reported from tropical soils. Dominance-diversity curves, based on nematode abundance, follow a similar ‘hollow curve’ pattern, with only 20 of the genera representing 84.6% of the total abundance, and only 12 of the genera representing 88% of the total biomass. Helicotylenchus, tylenchids, criconematids, Belondira, Longidorus, Xiphinema, Monotrichodorus, Prismatolaimus and Steinernema are important in the assemblages due their abundance or biomass in the different samples. Monotrichodorus and Discocriconemella appear related to undisturbed ecosystems, and they could have potential as disturbance indicators. Biomass-based dominance-diversity curves have similar qualitative and quantitative behavior to those observed in abundance distribution, but the dorylaims, Aporcelinus and Aporcelaimoides, which represented only the 0.35% of the abundance, having a major part of the total biomass (4.33%). NMDS analysis segregated locations into two groups, sampled sites were arranged according to the life zone where they belong. Ecosystems were segregated into natural ecosystems and plantations but having overlapping zones. Whereas RDA analysis indicated that organic matter and Cu are the most relevant edaphic variables for explaining the distribution of nematode assemblages, however few genera appear important in the ordination, Mesocriconema, Longidorus, Xiphinema and Belondira between them. | Se caracteriza la fauna de nematodos del suelo de cinco localidades ubicadas en el Parque Nacional del Agua (PNA) en Costa Rica. y analizado. Se muestrearon cuatro ecosistemas en cada ubicación: bosque primario (no perturbado), bosque secundario bosques (regenerados naturalmente), plantaciones de árboles (taladas y replantadas con árboles maderables) y pastos (talados de árboles). Se analizaron cinco muestras de suelo de 100 g en cada localidad y ecosistema, resultando un total de 100 muestras. Se identificaron ciento treinta y un géneros de nematodos y se determinó su abundancia y biomasa. estimado y analizado mediante escalamiento multidimensional no métrico (NMDS) y análisis de redundancia (RDA). La abundancia de nematodos observada fue de 1237 ± 520 especímenes por muestra de suelo durante todo el estudio. similar a lo reportado previamente en suelos tropicales. Curvas de dominancia-diversidad, basadas en la abundancia de nematodos, siguen un patrón similar de "curva hueca", con sólo 20 de los géneros representando el 84,6% de la abundancia total, y sólo 12 de los géneros representan el 88% de la biomasa total. Helicotylenchus, tylénquidos, criconemátidos, Belondira, Longidorus, Xiphinema, Monotrichodorus, Prismatolaimus y Steinernema son importantes en los ensamblajes. debido a su abundancia o biomasa en las diferentes muestras. Aparecen Monotrichodorus y Discocriconemella relacionados con ecosistemas no perturbados, y podrían tener potencial como indicadores de perturbación. Basado en biomasa Las curvas de dominancia-diversidad tienen un comportamiento cualitativo y cuantitativo similar a las observadas en abundancia. distribución, pero los dorylaims, Aporcelinus y Aporcelaimoides, que representaron sólo el 0,35% de la abundancia, representando la mayor parte de la biomasa total (4,33%). El análisis NMDS separó las ubicaciones en dos En los grupos, los sitios muestreados se ordenaron según la zona de vida a la que pertenecen. Los ecosistemas estaban segregados en ecosistemas naturales y plantaciones pero con zonas superpuestas. Mientras que el análisis de RDA indicó que la materia orgánica y el Cu son las variables edáficas más relevantes para explicar la distribución de los ensambles de nematodos, sin embargo pocos géneros parecen importantes en la ordenación, Mesocriconema, Longidorus, Xiphinema y Belondira entre ellos. | Universidad Nacional, Costa Rica | Elsevier, Países Bajos | Escuela de Ciencias Biológicas
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