46 research outputs found
Pluviolavado de cobre tras aplicaciones foliares de formulaciones de uso agrícola
No full textEl objetivo de este proyecto es identificar los factores que determinan el desprendimiento de los pesticidas de la superficie foliar por efecto de la lluvia y cuantificar su efecto sobre las pérdidas producidas. De este modo se pretenden obtener estimaciones de la cantidad de pesticidas que pueden llegar al suelo arrastradas por pluviolavado foliar en función de las características de la lluvia.
El método experimental constará de dos fases: una a escala de laboratorio con lluvia simulada, y otra a escala de parcela experimental con cultivos de vid y patata. En la fase de laboratorio se van a estudiar las variables de energía de impacto de gota y capacidad de arrastre de escurrimiento foliar, que influyen en la pérdida de pesticidas usados en agricultura; se trata de establecer una relación cuantitativa entre la energía cinética del agua que produce el desprendimiento de partículas de pesticidas, así como las pérdidas por disolución de los principios activos. En la fase de experimentos de campo se aplicarán series de dosis controladas de pesticidas en todo el ciclo del cultivo, correspondientes a los tratamientos recomendados; la parcela estará instrumentaliza para recoger muestras de pluviolavado que se analizarán posteriormente para cuantificar las pérdidas.
Se trata de determinar las características de la pérdida, la masa absoluta y su variación entre episodios, las concentraciones medias por episodio y la dependencia temporal de las pérdidas entre episodios sucesivos.
Se podrán establecer y comparar relaciones entre factores asociados a características físicas de la lluvia: energía de la lluvia, intensidad de la misma y diámetro de gota, energía de la capa de flujo de agua en el escurrimiento sobre la superficie tratada con el pesticida y la pérdida en forma de partículas en disolución. Se analizarán las interacciones de estos factores con la dosis de pesticida.
Estos resultados podrán ser transferidos a la industria agroalimentaria para establecer criterios de riesgo para la pérdida de pesticidas por pluviolavado y a la industria de agroquímicos para desarrollar formulados con una mayor efectividad y así reducir la contaminación.O obxectivo deste proxecto é identifica-los factores que determinan o desprendemento dos pesticidas da superficie foliar a consecuencia da choiva e cuantificar o seu efecto sobre as perdas producidas. Deste xeito, preténdense obter estimacións da cantidade de pesticidas que poden chegar ao solo levadas polo pluviolavado foliar en función das características da choiva.
O método experimental constará de dúas fases: unha a escala de laboratorio con choiva simulada e outra a escala de parcela experimental con cultivos de vide e pataca. Na fase de laboratorio vanse estuda-las variables de enerxía de impacto de gota e capacidade de arrastre do escoamento foliar, que inflúen na perda de pesticidas usados na agricultura; trátase de establecer unha relación cuantitativa entre a enerxía cinética da auga, que produce o desprendemento de partículas de pesticidas, e tamén as perdas por disolución dos principios activos. Na fase de experimentos de campo aplicaranse series de doses controladas de pesticidas ao longo do ciclo do cultivo, correspondentes aos tratamentos recomendados; a parcela estará instrumentalizada para recoller mostras de pluviolavado que se analizarán posteriormente para cuantifica-las perdas. Trátase de determinar as características das perdas, a masa absoluta e a súa variación entre episodios, as concentracións medias por episodio e a dependencia temporal das perdas entre episodios sucesivos.
Poderanse establecer e comparar relacións entre factores asociados ás características físicas da choiva: enerxía cinética da choiva, intensidade da mesma e diámetro de gota, enerxía da capa de fluxo de auga no escoamento sobre a superficie tratada co pesticida e a perda en forma de partículas en disolución. Analizaranse as interacións destes factores ca dose de pesticida.
Estes resultados poderán ser transferidos á industria agroalimentaria para establecer criterios de risco de perda de pesticidas por pluviolavado, e á industria de agroquímicos para desenvolver formulados cunha maior efectividade e reduci-la contaminación.Xunta de GaliciaMinisterio de Educación y Ciencia | Ref. AGL2006-04231/AGRConsellería de Innovación e Industria | Ref. PGIDIT06RAG38301P
Propiedades físicas del suelo bajo diferentes manejos: un análisis mediante exploración por TAC, experimentos de transporte y caracterización de saltos a presión.
No full textThis thesis will study the changes in the organization of soil pore space (soil architecture) in the transportation of water, solutes and colloids, and as a result of the application of conservation or ecological agriculture techniques, which can modify the properties of the soil together with transport.
The soil architecture has great importance in the transport through the soil. Cracks and biopores have the characteristics of continuity and connectivity that modulate transport. This has important implications for soil productivity and ecological functions (transport of water, gases, nutrients, metabolites, agrochemicals ... as well as in the processes of transformation of organic matter). The habitat structure of the biota that regulates many of these cycles is related to soil architecture. In this way, it is of paramount importance to discover relationships between architecture descriptors and soil properties, such as permeability, apparent density or hydraulic functions of the soil.
This approach emerges as a response to the EU's agricultural policy of replacing conventional agricultural management with techniques aimed at soil conservation, as this change leads to changes in soil architecture whose scope is unknown. The soils are going to be gaining a structure much more organized and stable in the time, with more macroporos, and connected in a different form than in the system of conventional tillage. In the context of non-tillage, conventional cultivation operations such as burial of amendments and compost, such as the use of fertilizers and mixtures of granular formulations with the soil, may be limited by the use of conventional techniques.
The challenge of reconciling the minimum tillage with the rest of the cultivation operations requires efforts in innovation to try to improve the techniques of application of organic fertilizers and minerals. This brings together research and innovation for the substitution or modification of conventional cultivation techniques.Nesta Tese estudaranse os cambios na organización do espazo de poros do solo (arquitectura do solo) no transporte de auga, solutos e coloides, e a consecuencia da aplicación de técnicas da agricultura de conservación ou ecolóxica, que poden modificar as propiedades do solo vencelladas ao transporte.
A arquitectura do solo ten gran importancia no transporte a través do solo. Fendas e bioporos teñen as características de continuidade e conectividade que modulan o transporte. Isto ten importantes implicacións na produtividade dos solos e as súas funcións ecolóxicas (transporte de auga, gases, nutrintes, metabolitos, agroquímicos... así como nos procesos de transformación da materia orgánica).
A estrutura do hábitat da biota que regula moitos destes ciclos está relacionada coa arquitectura do solo. Neste camiño, é de capital importancia descubrir relacións entre os descritores da arquitectura e as propiedades do solo, tales coma a permeabilidade, densidade aparente ou funcións hidráulicas do solo.
Este plantexamento xorde como resposta a política agraria da UE de substitución do manexo agrícola convencional por técnicas dirixidas a conservación do solo, pois este cambio vai conducir a modificacións na arquitectura do solo cuio alcance é descoñecido. Os solos van ir gañando unha estrutura moito máis organizada e estable no tempo, con máis macroporos, e conectados de diferente xeito que no sistema de laboreo convencional. Nun contexto de non laboreo as operacións de cultivo convencionais, tales como o enterramento de emendas e adubo, así coma o uso de fertilizantes e a mestura de formulados granulares có solo poden verse limitadas polo uso de técnicas convencionais.
O reto de compatibilizar o mínimo laboreo co resto das operacións de cultivo necesita esforzos en innovación para tratar de mellorar as técnicas de aplicación de adubos orgánicos e minerais. Isto leva aparellada investigación e innovación para substitución ou a modificación da técnicas convencionais de cultivo.En esta tesis se estudiarán los cambios en la organización del espacio de poros del suelo (arquitectura del suelo) en el trasporte de agua, solutos y coloides, y a consecuencia de la aplicación de técnicas de agricultura de conservación o ecológica, que pueden modificar las propiedades del suelo unidas al transporte.
La arquitectura del suelo tiene gran importancia en el trasporte a través del suelo. Grietas y bioporos tienen las características de continuidad y conectividad que modulan el transporte. Esto tiene importantes implicaciones en la productividad de los suelos y en sus funciones ecológicas (transporte de agua, gases, nutrientes, metabolitos, agroquímicos... así como en los procesos de transformación de materia orgánica). La estructura del hábitat de la biota que regula muchos de estos ciclos está relacionada con la agricultura del suelo. En este camino, es de capital importancia descubrir relaciones entre los descriptores de la arquitectura y las propiedades del suelo, tales como la permeabilidad, densidad aparente o funciones hidráulicas del suelo.
Este planteamiento surge como respuesta a la política agraria de la UE de substitución del manejo agrícola convencional por técnicas dirigidas a la conservación del suelo, pues este cambio va a conduce a modificaciones en la arquitectura del suelo cuyo alcance es desconocido. Los suelos van a ir ganando una estructura mucho más organizada y estable en el tiempo, con más macroporos, y conectados de una forma diferente que en el sistema de laboreo convencional. En un contexto de no laboreo las operaciones de cultivo convencionales, tales como el enterramiento de enmiendas y abono, así como el uso de fertilizantes y mezclas de formulados granulares con el suelo pueden verse limitadas por el suo de técnicas convencionales.
El reto de compatibilizar el mínimo laboreo con el resto de las operaciones de cultivo necesita esfuerzos en innovación para tratar de mejorar las técnicas de aplicación de abonos orgánicos y minerales. Esto lleva asociadas investigación e innovación para la substitución o la modificación de técnicas convencionales de cultivo
Feeding Mars: a pilot study growing vegetables using aquaponic effluent fertiliser in simulant and analogue Martian regoliths
No full textThe Feeding Mars study was devised as a small, pilot proof of concept study to research the potential for using aquaponic effluents as an additive to regoliths which on Mars and the Moon are devoid of organic material and thus lacking microbes which assist in the delivery of water and nutrients to the plants via their roots. This research investigates aquaponics as a way to potentially produce fish and vegetal products in regoliths on Mars and the Moon as well as in extreme environments on Earth. In order to settle on Mars, settlers will have to grow their own food in systems that are self-perpetuating, with little or no inputs being brought from Earth once these systems have been established. This means that nutrients from the fish water can be used to grow plants in the hydroponic parts of the aquaponic system but also potentially in the Martian regoliths which are treated with effluents taken from aquaponic systems. Once production is established additional nutrients can be sourced from the arisings and waste, both from the fish (that are processed and eaten) and the plants, which can be used as compost to turn the regoliths into soil. In order to have fish in space, there is also the need for the systems to be self-sustaining in the production of fish feed.
The key outcomes of the project were that all the species grown (potatoes, tomatoes, dwarf beans, carrots, lettuce, spring onions, chives and basil) indicate the potential to be grown in regoliths with the addition of aquaponic effluents. A significant result was that on the whole the plants that were grown with the addition of aquaponic effluents were greener than those grown in the horticultural soil, indicating that the nutrient supply was adequate. However, a key lesson learned is that germination and thus development of the plants grown in the Mars simulant and analogue was slower than those grown in the horticultural soil. Thus, developing nutrients in the soil before planting is necessary as it is with agriculture and horticulture practices on Earth, where manuring/fertilization occurs before planting. The consequence of this research, and the envisaged research to follow is not only for extra-terrestrial environments. The Earth has its own hostile environments, characterised with regoliths and other unproductive soils, and aquaponic water and aquaponic wastes can readily be envisaged as providing solutions to growing nutritious food in areas where agriculture is not currently viable. The research was undertaken in an exhibition gallery setting at the University of Greenwich in order to encourage public interest and dialogue, which it did
Transporte de fitosanitarios en formulaciones particuladas y granuladas de uso agrícola : mecanismos de filtración y difusión
No full textEl uso abusivo de agroquímicos para el control de enfermedades y plagas conlleva su acumulación en los suelos y el aumento del riesgo de contaminación con el consecuente peligro que supone tanto para la salud como para el medio.
Existen numerosas formulaciones comerciales en el mercado con distintas características que ayudan a su aplicación y mejoran su eficiencia. El enfoque clásico utilizado para estudiar la movilidad de los pesticidas en el suelo es la interacción del ingrediente activo puro con el suelo. Sin embargo, el tipo de formulación tiene una importancia crucial en el comportamiento y destino final del ingrediente activo en el medio. Conocer los mecanismos que gobiernan el transporte de estos formulados comerciales en medios porosos es de gran importancia a la hora de evaluar su riesgo ambiental, de poder ser implementados en los modelos existentes que predicen el movimiento de los ingredientes activos de los agroquímicos en el suelo y en las aguas subterráneas.
Por todo esto, en esta tesis se estudió el transporte dos tipos de formulaciones ampliamente utilizadas en agricultura. En la primera parte se pretende determinar los mecanismos de transporte de partículas coloidales de fungicidas con base cúprica en lechos porosos atendiendo a las condiciones químicas e hidrodinámicas del medio y a las características de las formulaciones comerciales, en especial al tamaño de partícula. En la segunda parte se evalúan los procesos de liberación y difusión de los ingredientes activos de formulaciones granuladas de liberación controlada. Se estudió el efecto que tiene la velocidad de infiltración de agua en un medio poroso en la tasa de liberación del ingrediente activo y los procesos implicados; así como el transporte difusivo del ingrediente activo desde los gránulos al medio cuando no existe movimiento de agua
Neonatal sensitization to ethanol-induced breathing disruptions as a function of late prenatal exposure to the drug in the rat: Modulatory effects of ethanol's chemosensory cues
No full textPreclinical and clinical studies have systematically demonstrated abrupt changes in fetal respiratory patterns when the unborn organism is exposed to the effects of maternal ethanol intoxication. In subprimates, chronic exposure to this drug during gestation and infancy results in marked alterations of the plasticity of the respiratory network. These alterations are manifested in terms of an early incapability to overcome deleterious effects of hypoxic events as well as in terms of sensitization to ethanol's depressant effects upon breathing patterns. It has also been demonstrated that near term rat fetuses process ethanol's chemosensory cues when the drug contaminates the amniotic fluid and that associative learning processes occur due to the temporal contiguity existing between these cues and different ethanol-related physiological effects. In the present study during the course of late gestation (gestational days 17-20), pregnant rats were intragastrically administered with either 0.0 or 2.0. g/kg ethanol. Seven-day-old pups derived of these dams were evaluated in terms of respiration rates (breaths/min) and apneas when subjected to different experimental conditions. These conditions were defined by postnatal exposure to the drug (intragastric administrations of either 0.0, 0.5, 1.0 or 2.0. g/kg ethanol), postadministration time of evaluation (5-10 or 30-35. min) and olfactory context at test (no explicit ambient odor or ethanol ambient odor). The results, obtained via whole body plethysmography, indicated that brief prenatal experience with the drug sensitized the organisms to ethanol's depressant effects particularly when employing the higher ethanol doses. In turn, presence of ethanol odor at test potentiated the above mentioned respiratory alterations. Prenatal treatment with ethanol was not found to alter pharmacokinetic profiles resulting from postnatal exposure to the drug or to affect different morphometric parameters related with lung development. These results indicate that even brief exposure to the drug during late gestation is sufficient to sensitize the organism to later disruptive effects of the drug upon breathing responsiveness. These deficits are potentiated through the re-exposure to the olfactory context perceived in utero which is known to be associated with ethanol's unconditioned effects. As a function of these observations it is possible to suggest a critical role of fetal sensory and learning capabilities in terms of modulating later ethanol-related breathing disruptions.Fil: Culleré, Marcela Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; ArgentinaFil: Macchione, Ana Fabiola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; ArgentinaFil: Haymal, Olga Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; ArgentinaFil: Paradelo, Martin. Universidad Nacional de Córdoba. Unidad Hospitalaria "San Roque"; ArgentinaFil: Langer, Marcos Daniel. Fuerza Aérea Argentina. Hospital Aeronáutico Córdoba; ArgentinaFil: Spear, Norman E.. University Of Binghamton; Estados UnidosFil: Molina, Juan Carlos. University Of Binghamton; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina. Universidad Nacional de Córdoba. Facultad de Psicología; Argentin
Remediation of Soils Contaminated by Fluoride Using a Fermentation Product of Seaweed (Eucheuma cottonii)
No full textThis research article was published by Hindawi in 2022is study investigated the e cacy of fermented seaweed (Eucheuma cottonii) on the remediation of uoride-contaminated soil.
e soil was amended with either 1.25, 3.0, or 5.0% (w/w) fermented seaweed (FSW), parallel with the controls (0%). e
amendment improved the physicochemical properties of the soil particularly pH regulated from strong alkaline (9.3) to neutral
(7.0) which is essential for germination, crop growth, and yield. e amount of water soluble- uoride (Ws-F) dropped from
81.7 ± 3.1 mg/kg to 42.7 ± 2.4, 33.7 ± 1.2, 19.6 ± 0.9, and 12 ± 1.3 mg/kg following 0, 1.25, 3, and 5% amendment dosage, re spectively. Most of the Ws-F was converted into exchangeable uoride (Ex-F) and to uoride-bound to iron and manganese (Fe/
Mn-F). Furthermore, the amendment also enhanced microbial mass and diversity in the soil. e FSW contains organic acids
which participate in ionic bonding with the multivalent cations in the soil. e formed compound participates in ion exchange
with clay or with anionic adsorption to positively charged clay sites at the edges. is interaction is further essential for enhancing
the uoride holding capacity of the soil. e use of seaweed reduced the bioavailability of uoride in the agricultural soils and had
positive e ects on promoting soil fertility. However, further studies to observe its e ects on crop performance is of signi cance
Hydroxyapatite-activated seaweed biochar for enhanced remediation of fluoride contaminated soil at various pH ranges
No full textThis study investigated the defluoridation efficiency of hydroxyapatite-activated seaweed (Eucheuma Cottonii) biochar (HSB) at various soil pH ranges (3â-11) while monitoring the impact of contact time (30Â min - 2.5Â h), adsorbent dosage (0.1â-0.5 g) as well as the initial fluoride concentration and compare its performance to its respective seaweed biochar (SB). Activation of SB with the hydroxyapatite lead to a shift in its point-zero-charge (pHPZC) from 6 to 7.4 broadening its defluoridation pH range from a solitary 5 to amid 3 through 11. The fluoride adsorption mechanism was found to follow both Langmuir (R2Â =Â 0.956) and Freundlich (R2Â =Â 0.942) isotherm models with a maximum defluoridation capacity of 3.03 mg/g equivalent to the defluoridation efficiency of 79. This is accounted to the existence of soil ions, SB active sites, and the attached hydroxyapatite, as fluoride adsorption sites each exhibiting a dissimilar fluoride removal mechanism. Therefore, the HSB could be a promising adsorbent for fluoride removal in the fluoride contaminated agricultural soils of inclusive pH ranges
Improvements in soil physical properties after long-term manure addition depend on soil and crop type
No full textManure application and crop rotation are common agricultural practices that can alter soil physical properties and affect soil functions. In this study, we assessed the effect of long-term manure fertilization (24 to 126 years) and crop type on soil hydraulic, aggregate and pore structural properties. Samples were collected from three long-term experiments (LTEs) in Sweden (silty clay, SiC), Germany (silt loam, SiL) and Denmark (sandy loam, SL). Measurements included water retention, air permeability and gas diffusivity measured at five matric potentials −3, −5, −10, −30 and −50 kPa, saturated hydraulic conductivity (Ksat), bulk density (ρb), and water-stable aggregates (WSA). The treatments at the three LTEs included various manure rates and crop sequences (winter wheat, maize, spring barley, and grass/clover). Results showed that long-term manure addition reduced ρb by an average of 3–6% for all three sites, and improved soil water retention, plant available water and WSA for most investigated plots. However, increasing manure rates for the SiL and SL sites did not result in further improvements in soil water retention, ρb and water-stable aggregates. The effect of manure on soil pore size distribution, gas transport, and Ksat varied with soil and crop type. Manure increased the porosity of pores 30 µm for wheat and maize plots in the SL site. Manure improved gas transport and Ksat in the wheat plots and decreased these properties in the barley plots regardless of soil texture. The maize plots in the SL site had well developed pore structure, while the pore structure in the SiL site was relatively poor. Grass plots had poorer gas transport than maize plots in the SL site despite the manure addition. The study shows that improvements in soil physical and chemical properties arising from manure application largely depend on the crops grown and the soil texture
Investigating the effects of fish effluents as organic fertilisers on onion (Allium cepa) yield, soil nutrients, and soil microbiome
No full textAlthough waste waters from aquaculture farms, known as fish effluents, have been shown to be a viable source of nutrients for crop production, their use is not permitted in organic production under the current European regulatory framework, Council Regulation (EU) 2018/848. In contrast, the use of livestock manure as fertiliser is allowed and indeed encouraged. In this work we tested the effects of two types of fish effluents – filtered and unfiltered fish waters – from an aquaponic system on the yield of onions (Allium cepa) and the soil nutrients and microbiome, compared with a fertilisation regime using composted horse manure. Soil fertility was enhanced by the addition of fish effluents, in particular in the soil treated with unfiltered fish water or sludge, which resulted in the soil with the highest nitrate content. Fertilisation with fish water and aerobically treated fish sludge resulted in higher yields than the manure, performing the best in all growth and yield measurements. The bulb weight and bulb diameter in the onions fertilised with manure were 102.43 g ± 7.26 and 61 mm ± 2.05 respectively, the ones fertilised with filtered fish effluents were 126 g ± 6.64 and 66.52 mm ± 2.17, and the ones fertilised with filtered (fish water) and unfiltered (sludge) fish effluents were 133.32 g ± 6.86 and 67.66 mm ± 1.81. The horse manure significantly affected the microbial community structure of the soil, resulting in a higher species diversity compared with the fish effluents, with the most predominant genus types being Flavobacterium, Pseudarthrobacter, Sphingomonas, Massilia, Nitrososphaera, Pseudomonas and Nocardioides. However, the microbial activity in the soil with fish effluents was also significant, which indicates that the soil treated in this way can be considered a ‘living soil’, as required for organic certification in the EU. Overall, the results confirm the findings of previous studies on the effectiveness of fish effluents as fertilisers, and highlight the superior performance of fish effluents compared with a livestock manure, thus directly questioning the prohibition on using fish effluents in organic agriculture
Investigating the effects of fish effluents as organic fertilisers on basil (Ocimum basilicum)
No full textWhilst the potential of fish effluents as nutrient sources for crop production has been demonstrated, their use in the European Union remains prohibited in organic farming. In this study, we investigate the efficacy in greenhouse basil cultivation of two types of fish effluents (filtered ‘fish water’ and unfiltered ‘fish sludge’) from an aquaponic system, and assess their role in maintaining and enhancing soil fertility as well as their potential to create a ’living soil’, which are two of the prerequisites for organic certification in the EU. To evaluate the contribution of fish effluents to plant growth in comparison with soil nutrients, basil plants were grown in pots containing two types of substrate: compost-free (without organic matter) and with compost (with organic matter). The results indicate that fish water and fish sludge demonstrate significant potential as fertilisers and outperform compost in certain parameters, such as plant biomass. The results also align with existing literature by demonstrating the positive impact of compost on soil microbial diversity, underscoring its role in fostering plant health. Although the treatments did not show differences in microbial composition at the genus level, the higher microbial diversity observed following fish effluent application highlights its potential for promoting ’living soil’. This research underscores the need for continued exploration of the implications of compost application in conjunction with fish effluent fertilisation on soil microbial communities and the production of specialty crops such as herbs
