Combined impacts of elevated CO2 and anthropogenic noise on European sea bass (Dicentrarchus labrax)

Ocean acidification (OA) and anthropogenic noise are both known to cause stress and induce physiological and behavioural changes in fish, with consequences for fitness. OA is also predicted to reduce the ocean's capacity to absorb low-frequency sounds produced by human activity. Consequently, anthropogenic noise could propagate further under an increasingly acidic ocean. For the first time, this study investigated the independent and combined impacts of elevated carbon dioxide (CO2) and anthropogenic noise on the behaviour of a marine fish, the European sea bass (Dicentrarchus labrax). In a fully factorial experiment crossing two CO2 levels (current day and elevated) with two noise conditions (ambient and pile driving), D. labrax were exposed to four CO2/noise treatment combinations: 400 µatm/ambient, 1000 µatm/ambient, 400 µatm/pile-driving, and 1000 µatm/pile driving. Pile-driving noise increased ventilation rate (indicating stress) compared with ambient noise conditions. Elevated CO2 did not alter the ventilation rate response to noise. Furthermore, there was no interaction effect between elevated CO2 and pile-driving noise, suggesting that OA is unlikely to influence startle or ventilatory responses of fish to anthropogenic noise. However, effective management of anthropogenic noise could reduce fish stress, which may improve resilience to future stressors.

Interactive effects of ocean acidification and rising sea temperatures alter predation rate and predator selectivity in reef fish communities

Ocean warming and acidification are serious threats to marine life. While each stressor alone has been studied in detail, their combined effects on the outcome of ecological interactions are poorly understood. We measured predation rates and predator selectivity of two closely related species of damselfish exposed to a predatory dottyback. We found temperature and CO2 interacted synergistically on overall predation rate, but antagonistically on predator selectivity. Notably, elevated CO2 or temperature alone reversed predator selectivity, but the interaction between the two stressors cancelled selectivity. Routine metabolic rates of the two prey showed strong species differences in tolerance to CO2 and not temperature, but these differences did not correlate with recorded mortality. This highlights the difficulty of linking species-level physiological tolerance to resulting ecological outcomes. This study is the first to document both synergistic and antagonistic effects of elevated CO2 and temperature on a crucial ecological process like predator-prey dynamics.

Effects of elevated CO2 on early life history development of the yellowtail kingfish, Seriola lalandi, a large pelagic fish

An increasing number of studies have examined the effects of elevated carbon dioxide (CO2) and ocean acidification on marine fish, yet little is known about the effects on large pelagic fish. We tested the effects of elevated CO2 on the early life history development and behaviour of yellowtail kingfish, Seriola lalandi. Eggs and larvae were reared in current day control (450 µatm) and two elevated CO2 treatments for a total of 6 d, from 12 h post-fertilization until 3 d post-hatching (dph). Elevated CO2 treatments matched projections for the open ocean by the year 2100 under RCP 8.5 (880 µatm CO2) and a higher level (1700 µatm CO2) relevant to upwelling zones where pelagic fish often spawn. There was no effect of elevated CO2 on survival to hatching or 3 dph. Oil globule diameter decreased with an increasing CO2 level, indicating potential effects of elevated CO2 on energy utilization of newly hatched larvae, but other morphometric traits did not differ among treatments. Contrary to expectations, there were no effects of elevated CO2 on larval behaviour. Activity level, startle response, and phototaxis did not differ among treatments. Our results contrast with findings for reef fish, where a wide range of sensory and behavioural effects have been reported. We hypothesize that the absence of behavioural effects in 3 dph yellowtail kingfish is due to the early developmental state of newly hatched pelagic fish. Behavioural effects of high CO2 may not occur until larvae commence branchial acid-base regulation when the gills develop; however, further studies are required to test this hypothesis. Our results suggest that the early stages of kingfish development are tolerant to rising CO2 levels in the ocean.

Sea urchins in a high CO2 world: partitioned effects of body-size, ocean warming and acidification on metabolic rate

Body-size and temperature are the major factors explaining metabolic rate, and the additional factor of pH is a major driver at the biochemical level. These three factors have frequently been found to interact, complicating the formulation of broad models predicting metabolic rates and hence ecological functioning. In this first study of the effects of warming and ocean acidification, and their potential interaction, on metabolic rate across a broad body-size range (two-to-three orders of magnitude difference in body mass) we addressed the impact of climate change on the sea urchin Heliocidaris erythrogramma in context with climate projections for east Australia, an ocean warming hotspot. Urchins were gradually introduced to two temperatures (18 and 23 °C) and two pH (7.5 and 8.0), and maintained for two months. That a new physiological steady-state had been reached, otherwise know as acclimation, was validated through identical experimental trials separated by several weeks. The relationship between body-size, temperature and acidification on the metabolic rate of H. erythrogramma was strikingly stable. Both stressors caused increases in metabolic rate; 20% for temperature and 19% for pH. Combined effects were additive; a 44% increase in metabolism. Body-size had a highly stable relationship with metabolic rate regardless of temperature or pH. None of these diverse drivers of metabolism interacted or modulated the effects of the others, highlighting the partitioned nature of how each influences metabolic rate, and the importance of achieving a full acclimation state. Despite these increases in energetic demand there was very limited capacity for compensatory modulating of feeding rate; food consumption increased only in the very smallest specimens, and only in response to temperature, and not pH. Our data show that warming, acidification and body-size all substantially affect metabolism and are highly consistent and partitioned in their effects, and for H. erythrogramma near-future climate change will incur a substantial energetic cost.

Tough as a rock-boring urchin: adult Echinometra sp. EE from the Red Sea show high resistance to ocean acidification over long-term exposures

Ocean acidification, a process caused by the continuous rise of atmospheric CO2 levels, is expected to have a profound impact on marine invertebrates. Findings of the numerous studies conducted in this field indicate high variability in species responses to future ocean conditions. This study aimed at understanding the effects of long-term exposure to elevated pCO2 conditions on the performance of adult Echinometra sp. EE from the Gulf of Aqaba (Red Sea). During an 11-month incubation under high pCO2 (1,433 µatm, pHNBS 7.7) and control (435 µatm, pHNBS 8.1) conditions, we examined the urchins' somatic and gonadal growth, gametogenesis and skeletal microstructure. Somatic and gonadal growths were exhibited with no significant differences between the treatments. In addition, all urchins in the experiment completed a full reproductive cycle, typical of natural populations, with no detectable impact of increased pCO2 on the timing, duration or progression of the cycle. Furthermore, scanning electron microscopy imaging of urchin tests and spines revealed no signs of the usual observed effects of acidosis, such as skeletal dissolution, widened stereom pores or non-smoothed structures. Our results, which yielded no significant impact of the high pCO2 treatment on any of the examined processes in the urchins studied, suggest high resistance of adult Echinometra sp. EE to near future ocean acidification conditions. With respect to other findings in this area, the outcome of this study provides an example of the complicated and diverse responses of echinoids to the predicted environmental changes.

Effects of ocean acidification on learning in coral reef fishes

Ocean acidification has the potential to cause dramatic changes in marine ecosystems. Larval damselfish exposed to concentrations of CO2 predicted to occur in the mid- to late-century show maladaptive responses to predator cues. However, there is considerable variation both within and between species in CO2 effects, whereby some individuals are unaffected at particular CO2 concentrations while others show maladaptive responses to predator odour. Our goal was to test whether learning via chemical or visual information would be impaired by ocean acidification and ultimately, whether learning can mitigate the effects of ocean acidification by restoring the appropriate responses of prey to predators. Using two highly efficient and widespread mechanisms for predator learning, we compared the behaviour of pre-settlement damselfish Pomacentrus amboinensis that were exposed to 440 µatm CO2 (current day levels) or 850 µatm CO2, a concentration predicted to occur in the ocean before the end of this century. We found that, regardless of the method of learning, damselfish exposed to elevated CO2 failed to learn to respond appropriately to a common predator, the dottyback, Pseudochromis fuscus. To determine whether the lack of response was due to a failure in learning or rather a short-term shift in trade-offs preventing the fish from displaying overt antipredator responses, we conditioned 440 or 700 µatm-CO2 fish to learn to recognize a dottyback as a predator using injured conspecific cues, as in Experiment 1. When tested one day post-conditioning, CO2 exposed fish failed to respond to predator odour. When tested 5 days post-conditioning, CO2 exposed fish still failed to show an antipredator response to the dottyback odour, despite the fact that both control and CO2-treated fish responded to a general risk cue (injured conspecific cues). These results indicate that exposure to CO2 may alter the cognitive ability of juvenile fish and render learning ineffective.

Optimización del Abonado Nitrogenado en el Melón (Cucumis Melo L.) Tipo Piel de Sapo

Spain is the fifth-largest producer of melon (Cucumis melo L.) and the second exporter in the world. To a national level, Castilla-La Mancha emphasize and, specifically, Ciudad Real, where is cultivated 27% of national area dedicated to this crop and 30% of melon national production. Melon crop is cultivating majority in Ciudad Real and it is mainly located in the Alto Guadiana, where the major aquifers of the region are located, the aquifer 23 or Mancha Occidental and the aquifer 24 or Campo de Montiel, both declared overexploited and vulnerable zones to nitrate pollution from agricultural sources. The problem is exacerbated because in this area, groundwater is the basic resource of supply to populations, and even often the only one. Given the importance of melon in the area, recent research has focused on the irrigation of melon crop. Unfortunately, scant information has been forthcoming on the effect of N fertilizer on melon piel de sapo crop, so it is very important to tackle in a serious study that lead to know the N requirements on the melon crop melon by reducing the risks of contamination by nitrate leaching without affecting productivity and crop quality. In fact, the recommended dose is often subjective and practice is a N overdose. In this situation, the taking of urgent measures to optimize the use of N fertilization is required. To do it, the effect of N in a melon crop, fertirrigated and on plastic mulch, was studied. The treatments consisted in different rates of N supply, considering N fertilizer and N content in irrigation water, so the treatment applied were: 30 (N30), 85 (N85), 112 (N112) and 139 (N139) Kg N ha-1 in 2005; 93 (N93), 243 (N243) and 393 (N393) kg ha-1 in 2006; and 11 (N11), 61 (N61), 95 (N95) and 148 (N148) kg ha-1 in 2007. A randomized complete-block design was used and each treatment was replicated four times. The results showed a significant effect of N on dry biomass and two patterns of growth were observed. On the one hand, a gradual increase in vegetative biomass of the plant, leaves and stem, with increasing N, and on the other hand, an increase of fruit biomass also with increasing N up to a maximum of biomass corresponding to the optimal dose determined in 90 kg ha-1 of N applied, corresponding to 160 kg ha-1 of N available for melon crop, since this optimum dose, the fruit biomass suffers a decline. A significant effect was observed in concentration and N uptake in leaf, steam, fruit and whole plant, increasing in all of them with increasing of N doses. Fast N uptake occurred from 30-35 to 70-80 days after transplanting, coinciding with the fruit development. The N had a clear influence on the melon yield, its components, skin thickness and flesh ratio. The melon yield increased, as the mean fruit weight and number of fruits per m2 with increasing N until achieve an above 95% of the maximum yield when the N applied is 90 kg ha-1 or 160 kg ha-1 of N available. When N exceeds the optimal amount, there is a decline in yield, reducing the mean fruit weight and number of fruits per square meter, and was also observed a decrease in fruit quality by increasing the skin thickness and decrease the flesh ratio, which means an increase in fruit hollowed with excessive N doses. There was a trend for all indexes of N use efficiency (NUE) to decline with increasing N rate. We observed two different behaviours in the calculation result of the NUE; on the one hand, all the efficiency indexes calculated with N applied and N available had an exponential trend, and on the other hand, all the efficiency indexes calculated with N uptake has a linear trend. The linear regression cuts the exponential curve, delimiting a range within which lies the optimum quantity of N. The N leaching as nitrates increased exponentially with the amount of N. The increase of N doses was affected on the N mineralization. There was a negative exponential effect of N available on the mineralization of this element that occurs in the soil during the growing season, calculated from the balances of this element. The study of N leaching for each N rate used, allowed to us to establish several environmental indices related to environmental risk that causes the use of such doses, a simple way for them to be included in the code of Best Management Practices.

High power beam dump project for the accelerator prototype LIPAc: Cooling design and analysis

En el campo de la fusión nuclear y desarrollándose en paralelo a ITER (International Thermonuclear Experimental Reactor), el proyecto IFMIF (International Fusion Material Irradiation Facility) se enmarca dentro de las actividades complementarias encaminadas a solucionar las barreras tecnológicas que aún plantea la fusión. En concreto IFMIF es una instalación de irradiación cuya misión es caracterizar materiales resistentes a condiciones extremas como las esperadas en los futuros reactores de fusión como DEMO (DEMOnstration power plant). Consiste de dos aceleradores de deuterones que proporcionan un haz de 125 mA y 40 MeV cada uno, que al colisionar con un blanco de litio producen un flujo neutrónico intenso (1017 neutrones/s) con un espectro similar al de los neutrones de fusión [1], [2]. Dicho flujo neutrónico es empleado para irradiar los diferentes materiales candidatos a ser empleados en reactores de fusión, y las muestras son posteriormente examinadas en la llamada instalación de post-irradiación. Como primer paso en tan ambicioso proyecto, una fase de validación y diseño llamada IFMIFEVEDA (Engineering Validation and Engineering Design Activities) se encuentra actualmente en desarrollo. Una de las actividades contempladas en esta fase es la construcción y operación de una acelarador prototipo llamado LIPAc (Linear IFMIF Prototype Accelerator). Se trata de un acelerador de deuterones de alta intensidad idéntico a la parte de baja energía de los aceleradores de IFMIF. Los componentes del LIPAc, que será instalado en Japón, son suministrados por diferentes países europeos. El acelerador proporcionará un haz continuo de deuterones de 9 MeV con una potencia de 1.125 MW que tras ser caracterizado con diversos instrumentos deberá pararse de forma segura. Para ello se requiere un sistema denominado bloque de parada (Beam Dump en inglés) que absorba la energía del haz y la transfiera a un sumidero de calor. España tiene el compromiso de suministrar este componente y CIEMAT (Centro de Investigaciones Energéticas Medioambientales y Tecnológicas) es responsable de dicha tarea. La pieza central del bloque de parada, donde se para el haz de iones, es un cono de cobre con un ángulo de 3.5o, 2.5 m de longitud y 5 mm de espesor. Dicha pieza está refrigerada por agua que fluye en su superficie externa por el canal que se forma entre el cono de cobre y otra pieza concéntrica con éste. Este es el marco en que se desarrolla la presente tesis, cuyo objeto es el diseño del sistema de refrigeración del bloque de parada del LIPAc. El diseño se ha realizado utilizando un modelo simplificado unidimensional. Se han obtenido los parámetros del agua (presión, caudal, pérdida de carga) y la geometría requerida en el canal de refrigeración (anchura, rugosidad) para garantizar la correcta refrigeración del bloque de parada. Se ha comprobado que el diseño permite variaciones del haz respecto a la situación nominal siendo el flujo crítico calorífico al menos 2 veces superior al nominal. Se han realizado asimismo simulaciones fluidodinámicas 3D con ANSYS-CFX en aquellas zonas del canal de refrigeración que lo requieren. El bloque de parada se activará como consecuencia de la interacción del haz de partículas lo que impide cualquier cambio o reparación una vez comenzada la operación del acelerador. Por ello el diseño ha de ser muy robusto y todas las hipótesis utilizadas en la realización de éste deben ser cuidadosamente comprobadas. Gran parte del esfuerzo de la tesis se centra en la estimación del coeficiente de transferencia de calor que es determinante en los resultados obtenidos, y que se emplea además como condición de contorno en los cálculos mecánicos. Para ello por un lado se han buscado correlaciones cuyo rango de aplicabilidad sea adecuado para las condiciones del bloque de parada (canal anular, diferencias de temperatura agua-pared de decenas de grados). En un segundo paso se han comparado los coeficientes de película obtenidos a partir de la correlación seleccionada (Petukhov-Gnielinski) con los que se deducen de simulaciones fluidodinámicas, obteniendo resultados satisfactorios. Por último se ha realizado una validación experimental utilizando un prototipo y un circuito hidráulico que proporciona un flujo de agua con los parámetros requeridos en el bloque de parada. Tras varios intentos y mejoras en el experimento se han obtenido los coeficientes de película para distintos caudales y potencias de calentamiento. Teniendo en cuenta la incertidumbre de las medidas, los valores experimentales concuerdan razonablemente bien (en el rango de 15%) con los deducidos de las correlaciones. Por motivos radiológicos es necesario controlar la calidad del agua de refrigeración y minimizar la corrosión del cobre. Tras un estudio bibliográfico se identificaron los parámetros del agua más adecuados (conductividad, pH y concentración de oxígeno disuelto). Como parte de la tesis se ha realizado asimismo un estudio de la corrosión del circuito de refrigeración del bloque de parada con el doble fin de determinar si puede poner en riesgo la integridad del componente, y de obtener una estimación de la velocidad de corrosión para dimensionar el sistema de purificación del agua. Se ha utilizado el código TRACT (TRansport and ACTivation code) adaptándalo al caso del bloque de parada, para lo cual se trabajó con el responsable (Panos Karditsas) del código en Culham (UKAEA). Los resultados confirman que la corrosión del cobre en las condiciones seleccionadas no supone un problema. La Tesis se encuentra estructurada de la siguiente manera: En el primer capítulo se realiza una introducción de los proyectos IFMIF y LIPAc dentro de los cuales se enmarca esta Tesis. Además se describe el bloque de parada, siendo el diseño del sistema de rerigeración de éste el principal objetivo de la Tesis. En el segundo y tercer capítulo se realiza un resumen de la base teórica así como de las diferentes herramientas empleadas en el diseño del sistema de refrigeración. El capítulo cuarto presenta los resultados del relativos al sistema de refrigeración. Tanto los obtenidos del estudio unidimensional, como los obtenidos de las simulaciones fluidodinámicas 3D mediante el empleo del código ANSYS-CFX. En el quinto capítulo se presentan los resultados referentes al análisis de corrosión del circuito de refrigeración del bloque de parada. El capítulo seis se centra en la descripción del montaje experimental para la obtención de los valores de pérdida de carga y coeficiente de transferencia del calor. Asimismo se presentan los resultados obtenidos en dichos experimentos. Finalmente encontramos un capítulo de apéndices en el que se describen una serie de experimentos llevados a cabo como pasos intermedios en la obtención del resultado experimental del coeficiente de película. También se presenta el código informático empleado para el análisis unidimensional del sistema de refrigeración del bloque de parada llamado CHICA (Cooling and Heating Interaction and Corrosion Analysis). ABSTRACT In the nuclear fusion field running in parallel to ITER (International Thermonuclear Experimental Reactor) as one of the complementary activities headed towards solving the technological barriers, IFMIF (International Fusion Material Irradiation Facility) project aims to provide an irradiation facility to qualify advanced materials resistant to extreme conditions like the ones expected in future fusion reactors like DEMO (DEMOnstration Power Plant). IFMIF consists of two constant wave deuteron accelerators delivering a 125 mA and 40 MeV beam each that will collide on a lithium target producing an intense neutron fluence (1017 neutrons/s) with a similar spectra to that of fusion neutrons [1], [2]. This neutron flux is employed to irradiate the different material candidates to be employed in the future fusion reactors, and the samples examined after irradiation at the so called post-irradiative facilities. As a first step in such an ambitious project, an engineering validation and engineering design activity phase called IFMIF-EVEDA (Engineering Validation and Engineering Design Activities) is presently going on. One of the activities consists on the construction and operation of an accelerator prototype named LIPAc (Linear IFMIF Prototype Accelerator). It is a high intensity deuteron accelerator identical to the low energy part of the IFMIF accelerators. The LIPAc components, which will be installed in Japan, are delivered by different european countries. The accelerator supplies a 9 MeV constant wave beam of deuterons with a power of 1.125 MW, which after being characterized by different instruments has to be stopped safely. For such task a beam dump to absorb the beam energy and take it to a heat sink is needed. Spain has the compromise of delivering such device and CIEMAT (Centro de Investigaciones Energéticas Medioambientales y Tecnológicas) is responsible for such task. The central piece of the beam dump, where the ion beam is stopped, is a copper cone with an angle of 3.5o, 2.5 m long and 5 mm width. This part is cooled by water flowing on its external surface through the channel formed between the copper cone and a concentric piece with the latter. The thesis is developed in this realm, and its objective is designing the LIPAc beam dump cooling system. The design has been performed employing a simplified one dimensional model. The water parameters (pressure, flow, pressure loss) and the required annular channel geometry (width, rugoisty) have been obtained guaranteeing the correct cooling of the beam dump. It has been checked that the cooling design allows variations of the the beam with respect to the nominal position, being the CHF (Critical Heat Flux) at least twice times higher than the nominal deposited heat flux. 3D fluid dynamic simulations employing ANSYS-CFX code in the beam dump cooling channel sections which require a more thorough study have also been performed. The beam dump will activateasaconsequenceofthe deuteron beam interaction, making impossible any change or maintenance task once the accelerator operation has started. Hence the design has to be very robust and all the hypotheses employed in the design mustbecarefully checked. Most of the work in the thesis is concentrated in estimating the heat transfer coefficient which is decisive in the obtained results, and is also employed as boundary condition in the mechanical analysis. For such task, correlations which applicability range is the adequate for the beam dump conditions (annular channel, water-surface temperature differences of tens of degrees) have been compiled. In a second step the heat transfer coefficients obtained from the selected correlation (Petukhov- Gnielinski) have been compared with the ones deduced from the 3D fluid dynamic simulations, obtaining satisfactory results. Finally an experimental validation has been performed employing a prototype and a hydraulic circuit that supplies a flow with the requested parameters in the beam dump. After several tries and improvements in the experiment, the heat transfer coefficients for different flows and heating powers have been obtained. Considering the uncertainty in the measurements the experimental values agree reasonably well (in the order of 15%) with the ones obtained from the correlations. Due to radiological reasons the quality of the cooling water must be controlled, hence minimizing the copper corrosion. After performing a bibligraphic study the most adequate water parameters were identified (conductivity, pH and dissolved oxygen concentration). As part of this thesis a corrosion study of the beam dump cooling circuit has been performed with the double aim of determining if corrosion can pose a risk for the copper beam dump , and obtaining an estimation of the corrosion velocitytodimension the water purification system. TRACT code(TRansport and ACTivation) has been employed for such study adapting the code for the beam dump case. For such study a collaboration with the code responsible (Panos Karditsas) at Culham (UKAEA) was established. The work developed in this thesis has supposed the publication of three articles in JCR journals (”Journal of Nuclear Materials” y ”Fusion Engineering and Design”), as well as presentations in more than four conferences and relevant meetings.

Optimización de la aplicación de lodos de depuración de aguas residuales al abonado o mejora de suelos

El objetivo de este trabajo de investigación fue evaluar el efecto de la aplicación de lodos residuales procedentes de una planta de tratamiento de aguas residuales acondicionados como biosólido para el abonado de tres cultivos agrícolas. Esto se realizó a través del estudio de las variables de producción (desarrollo vegetal de cada cultivo) y de la comparación de las características de los suelos utilizados antes y después de los ensayos experimentales. A través de la investigación se confirmó la mejora en la calidad del suelo y mejor rendimiento de cultivo debido a los biosólidos procedentes de tratamiento de aguas residuales. Este trabajo de investigación de tipo descriptivo y experimental, utilizó lodos optimizados que fueron aplicados a tres cultivos agrícolas de ciclo corto. Fueron evaluados dos cultivos (sandía y tomate) bajo riego y un cultivo (arroz) en secano. En la primera fase del trabajo se realizó la caracterización de los lodos, para ellos se realizaron pruebas físico químicas y microbiológicas. Fue utilizado el método de determinación de metales por espectrometría de emisión atómica de plasma acoplado inductivamente, (ICP-AES) para conocer las concentraciones de metales. La caracterización microbiológica para coliformes totales y fecales se realizó utilizando la técnica del Número más probable (NMP), y para la identificación de organismos patógenos se utilizó el método microbiológico propuesto por Kornacki & Johnson (2001), que se fundamenta en dos procesos: pruebas presuntivas y prueba confirmativa. Tanto los resultados para la determinación de metales y elementos potencialmente tóxicos; como las pruebas para la determinación de microorganismos potencialmente peligrosos, estuvieron por debajo de los límites considerados peligrosos establecidos por la normativa vigente en Panama (Reglamento Técnico COPANIT 47-2000). Una vez establecido la caracterización de los lodos, se evalúo el potencial de nutrientes (macro y micro) presentes en los biosólidos para su potencial de uso como abono en cultivos agrícolas. El secado de lodos fue realizado a través de una era de secado, donde los lodos fueron deshidratados hasta alcanzar una textura pastosa. “La pasta de lodo” fue transportada al área de los ensayos de campo para continuar el proceso de secado y molida. Tres ensayos experimentales fueron diseñados al azar con cinco tratamientos y cuatro repeticiones para cada uno de los tres cultivos: sandía, tomate, arroz, en parcelas de 10m2 (sandía y tomate) y 20 m2 (arroz) para cada tratamiento. Tres diferentes dosis de biosólidos fueron evaluadas y comparadas con un tratamiento de fertilizante comercial y un tratamiento control. La dosis de fertilizante comercial utilizada en cada cultivo fue la recomendada por el Instituto de Investigación Agropecuaria de Panamá. Los ensayos consideraron la caracterización inicial del suelo, la preparación del suelo, semilla, y arreglo topográfico de los cultivos siguiendo las recomendaciones agronómicas de manejo de cultivo establecida por el Instituto de Investigación Agropecuaria. Para los ensayos de sandía y tomate se instaló el sistema de riego por goteo. Se determinaron los ácidos húmicos presentes en los cultivos, y se estudiaron las variables de desarrollo de cada cultivo (fructificación, cosecha, peso de la cosecha, dimensiones de tamaño y color de las frutas, rendimiento, y la relación costo – rendimiento). También se estudiaron las variaciones de los macro y micro nutrientes y las variaciones de pH, textura de suelo y MO disponible al inicio y al final de cada uno de los ensayos de campo. Todas las variables y covariables fueron analizadas utilizando el programa estadístico INFOSAT (software para análisis estadístico de aplicación general) mediante el análisis de varianza, el método de comparaciones múltiples propuesto por Fisher (LSD Fisher) para comparar las medias de los cultivares y el coeficiente de correlación de Pearson que nos permite analizar si existe una asociación lineal entre dos variables. En la evaluación de los aportes del biosólido a los cultivos se observó que los macronutrientes N y P se encontraban de los límites requeridos en cada uno de los cultivos, pero que los niveles de K estuvieron por debajo de los requerimientos de los cultivos. A nivel de la fertilización tradicional con fertilizante químico se observó que la dosis recomendada para cada uno de los cultivos del estudio estaba sobreestimada en los tres principales macronutrientes: Nitrógeno, Fosforo y Potasio. Contenían concentraciones superiores de N, P y K a las requeridas teóricamente por el cultivo. El nutriente que se aporta en exceso es el Fósforo. Encontramos que para el cultivo de sandía era 18 veces mayor a lo requerido por el cultivo, en tomate fue 12 veces mayor y en el cultivo de arroz, 34 veces mayor. El fertilizante comercial tuvo una influencia en el peso final y rendimiento final en cada uno de los cultivos del estudio. A diferencia, los biosólidos tuvieron una influencia directa en el desarrollo de los cultivos (germinación, coloración, tamaño, longitud, diámetro, floración y resistencia a enfermedades). Para el caso de la sandía la dosis de biosólido más cercana al óptimo para el cultivo es la mayor dosis aplicada en este ensayo (97.2 gramos de biosólido por planta). En el caso de tomate, el fertilizante comercial obtuvo los mejores valores, pero las diferencias son mínimas con relación al tratamiento T1, de menor dosis de biosólido (16.2 gramos de biosólido por planta). Los resultados generales del ensayo de tomate estuvieron por debajo del rendimiento esperado para el cultivo. Los tratamientos de aplicación de biosólidos aportaron al desarrollo del cultivo en las variables tamaño, color y resistencia a las enfermedades dentro del cultivo de tomate. Al igual que el tomate, en el caso del arroz, el tratamiento comercial obtuvo los mejores resultados. Los resultados finales de peso y rendimiento del cultivo indican que el tratamiento (T2), menor dosis de biosólido (32.4 gramos por parcela), no tuvo diferencias significativas con los resultados obtenidos en las parcelas con aplicación de fertilizante comercial (T1). El tratamiento T4 (mayor dosis de biosólido) obtuvo los mejores valores para las variables germinación, ahijamiento y espigamiento del cultivo, pero al momento de la maduración obtuvo los menores resultados. Los biosólidos aportan nutrientes a los cultivos y al final del ensayo se observó que permanecen disponibles en el suelo, aportando a la mejora del suelo final. En los tres ensayos, se pudo comprobar que los aportes de los biosólidos en el desarrollo vegetativo de los cultivos. También se encontró en todos los ensayos que no hubo diferencias significativas (p > 0.05) entre los tratamientos de biosólidos y fertilizante comercial. Para obtener mejores resultados en estos tres ensayos se requeriría que a la composición de biosólidos (utilizada en este ensayo) se le adicione Potasio, Calcio y Magnesio en las cantidades requeridas por cada uno de los cultivos. ABSTRACT The objective of this investigation was to evaluate the effect of residual sewage sludge obtained from the residual water of a treatment plant conditioned as Biosolid used on three reliable agricultural crops. The effect of the added sewage sludge was evaluated through the measurement of production variables such as crop plant development and the comparison of the soil characteristics used before and after the experimental tests. This investigation confirmed that biosolids from wastewater treatment can contribute to the growth of these crops. In this experimental approach, optimized sludge was applied to three short-cycle crops including two low-risk crops (watermelon and tomato) and one high-risk crop (rice) all grown on dry land. In the first phase of work, the characteristics of the sludge were assessed using chemical, physical and microbiological tests. The concentrations of metals were determined by atomic emission spectrometry inductively coupled plasma, (ICP-AES). Microbiological characterization was performed measuring total coliform and fecal count using the most probable number technique (NMP) and microbiological pathogens were identified using Kornacki & Johnson (2001) method based on two processes: presumptive and confirmatory tests. Both the results for the determination of metals and potentially toxic elements, as testing for the determination of potentially dangerous microorganisms were below the limits established by the applicable standard in Panama (Technical Regulate COPANIT 47-2000). After the metal and bacterial characterization of the sludge, the presence of macro or micronutrients in biosolids was measured to evaluate its potential for use as fertilizer in the growth of agricultural crops. The sludge was dehydrated via a drying process into a muddy slurry. The pulp slurry was transported to the field trial area to continue the process of drying and grinding. Three randomized experimental trials were designed to test with five treatment regimens and four replications for each of the crops: watermelon, tomato, rice. The five treatment regimens evaluated were three different doses of bio solid with commercial fertilizer treatment control and no fertilizer treatment control. Treatment areas for the watermelon and tomato were 10m2 plots land and for rice was 20m2. The amount of commercial fertilizer used to treat each crop was based on the amount recommended by Agricultural Research Institute of Panama. The experimental trials considered initial characterization of soil, soil preparation, seed, and crop topographical arrangement following agronomic crop management recommendations. For the tests evaluating the growth of watermelons and tomatoes and drip irrigation system was installed. The amount of humic acids present in the culture were determined and developmental variable of each crop were studied (fruiting crop harvest weight, size dimensions and color of the fruit, performance and cost effectiveness). Changes in macro and micronutrients and changes in pH, soil texture and OM available were measured at the beginning and end of each field trial. All variables and covariates were analyzed using INFOSAT statistical program (software for statistical analysis of general application) by analysis of variance, multiple comparisons method as proposed by Fisher (LSD Fisher) to compare the means of cultivars and the Pearson ratio that allows us to analyze if there is a linear association between two variables. In evaluating the contribution of biosolids to agricultural crops, the study determined that the macronutrients N & P were within the requirements of crops, but K levels were below the requirements of crops. In terms of traditional chemical fertilizer fertilization, we observed that the recommended dose for each study crop was overestimated for the three major nutrients: nitrogen, phosphorus and potassium. Higher concentrations containing N, P and K to the theoretically required by the crop. The recommended dose of commercial fertilizer for crops study contained greater amounts of phosphorus, crops that need. The level of phosphorous was found to be18 times greater than was required for the cultivation of watermelon; 12 times higher than required for tomato, and 34 times higher than required for rice cultivation. Phosphorus inputs of commercial fertilizer were a primary influence on the weight and performance of each crop. Unlike biosolids had a direct influence on crop development (germination, color, size, length, diameter, flowering and disease resistance). In the case of growth of watermelons, the Biosolid dose closest to the optimum for cultivation was applied the highest dose in this assay (97.2 grams of bio solids per plant). In the case of tomatoes, commercial fertilizer had the best values but the differences were minimal when compared to treatment T1, the lower dose of sewage sludge (Biosolid 16.2 grams per plant). The overall results for the tomato crop yield of the trial were lower than expected. Additionally, the application of biosolids treatment contributed to the development of fruit of variable size, color and disease resistance in the tomato crops. Similar to the tomato crop, commercial fertilizer treatment provided the best results for the rice crop. The final results of weight and crop yield for rice indicated that treatment with T2 amount of biosolids (34.2 grams per plot) was not significantly different from the result obtained in the application plot given commercial fertilizer (T1). The T4 (higher dose of bio solid) treatment had the best values for the germination, tillering and bolting variables of the rice crop but for fruit ripening yielded lower results. In all three trials, biosolids demonstrated the ability to contribute in the vegetative growth of crops. It was also found in all test no significant differences (p>0.05) between treatment of bio solid and commercial fertilizer. Biosolids provided nutrients to the crops and even at the end of the trial remained available in the ground soil, contributing to the improvement of the final ground. The best results from these three trials is that the use of bio solids such as those used in this assay would require the addition of potassium, calcium and magnesium in quantities required for each crop.

Uso de Metarhizium spp. na produção de mudas pré-brotadas de cana-de-açúcar e seus efeitos na planta, em pragas e doenças

Os fungos do gênero Metarhizium são entomopatogênicos e ainda apresentam relações endofíticas e podem viver saprofiticamente no solo. A associação desses microrganismos com insetos é bem conhecida, mas as interações diretas com as plantas ainda são incipientes. Objetivou-se com este estudo, determinar a capacidade de colonização endofítica em raízes de cana-de-açúcar (Saccharum spp.) de M. robertsii, M. anisopliae e três linhagens brasileiras recém-descobertas, bem como revelar o potencial destes fungos como antagonistas a dois fungos fitopatogênicos responsáveis pela podridão-vermelha (Fusarium moniliforme e Colletotrichum falcatum) e no controle de duas importantes pragas, a broca da cana-de-açúcar, Diatraea saccharalis e o nematóide-das-galhas, Meloidogyne javanica. Foram utilizados 24 isolados de Metarhizium spp. nos experimentos de promoção de crescimento de plantas após a inoculação em gemas de cana-de-açúcar em condições de casa-de-vegetação e campo. O efeito da inoculação do fungo em mudas de cana-de-açúcar foi investigado quanto a mortalidade e redução no desenvolvimento de D. saccharalis e redução nas populações de M. javanica. Experimentos de inibição in vitro em cultivo pareado foram conduzidos com os fungos F. moniliforme e C. falcatum e Trichoderma harzianum. Além disto, foram realizados testes qualitativos \"in vitro\" para avaliar a capacidade desses fungos em produzir β-1,3-Glucanase e Sideróforos. A inoculação de Metarhizium de todas as espécies testadas promoveu o crescimento de parte aérea, peso úmido e seco de raízes em relação ao controle (água). Enquanto o tratamento de gemas rotineiramente usado na usina onde se realizou a produção de mudas pré-brotadas com aplicação do fungicida Comet® + o fertilizante Biozyme TF resultou em pegamento de 32% e 59,6%, apenas com o uso de isolados de Metarhizium spp. estes valores foram de até 50% e 86,4%, nos dois experimentos em campo, respectivamente. As mortalidades observadas em lagartas de D. saccharalis que se alimentaram das plantas inoculadas com isolados de Metarhizium spp. atingiram valores de até 80%, sendo a mortalidade confirmada pela esporulação do fungo de até 55%. As lagartas sobreviventes apresentaram menor peso do que aquelas do controle não tratado. A inoculação de Metarhizium spp. em mudas de cana-de-açúcar conferiu proteção a M. javanica, resultando em uma densidade de massa de ovos por grama de raiz nas mudas inoculadas com o fungo até 59,8% menor no primeiro experimento e 64,1% menor no segundo em relação as mudas sem inoculação. Os ensaios de antagonismo mostraram que, todos os isolados de Metarhizium spp. apresentaram alguma forma de inibição tanto para F. moniliforme como para C. falcatum. Dos 24 isolados testados, 20,8% produziram a enzima hidrolítica, β-1,3-glucanase, o que pode estar associado a capacidade de inibição dos fungos fitopatogênicos. Constatou-se que 8 (33,3%) dos isolados produziram sideróforos e sugere que esses fungos apresentam mecanismos de disponibilização do ferro. O conhecimento gerado com este estudo poderá subsidiar novas estratégias de utilização de Metarhizium spp. em campo na produção de MPB de cana-de-açúcar.

Bubble sizes in waters of the Atlantic Ocean

Typical size of bubbles obtained from cavitation inception pressure measured in the surface layer of the Atlantic Ocean in situ aboard R/V Professor Vize in 1971 and Nerey in 1973 are reported. These results do not contradict ones of bubble size measurements using optical or acoustical techniques. Variability of bubble size is discovered and described. This variability is related to passing from one geographical region to another (from 68°55'S to 61°52'N), to changes in depth (from 5 to 100 m) and in day time, as well as to spatial fluctuations within an aquatic area. It is suggested that, in addition to wave breaking, there is another source of bubbles at depth 10-20 m that associates with hydrobiological processes.

Safety evaluation of renovated wastewater from a poultry processing plant /

"Grant nos. R804286 & S803325."

Mitteilungen aus der Königlichen Landesanstalt für Wasserhygiene zu Berlin-Dahlem.

Mode of access: Internet.

Determining resource quality and potential reasons for impairment of Illinois streams, inland lakes, and Lake Michigan : (Methods used for 2002 305(b) reporting).

According to Section 305(b) of the Clean Water Act (i.e. a generic name that refers to the Federal Water Pollution Control Act of 1972, the Clean Water Act of 1977, and subsequent amendments) and guidance provided by the United States Environmental Protection Agency (USEPA), each state must prepare and submit annually to the U.S. Congress and the USEPA report that describes the resource quality of the surface waters of the state. Every other year, this report, commonly referred to as the "305(b) report," must be provided in written form, whereas in alternate years each state may submit an electronic database to meet the reporting requirement. In the 305(b) report, states must also explain how they determined the resource quality of the waters of the state in terms of the degree to which predefined beneficial uses of those waters are supported. Also, in the 305(b) report when any designated use for any water body is not fully supported, the state must report potential reasons for the impairment. Herein, is explained how the Illinois Environmental Protection Agency determines the resource quality of Illinois streams, inland lakes, and Lake Michigan.