968 resultados para expectation of soil loss map


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Abstract: Preferential flow and transport through macropores affect plant water use efficiency and enhance leaching of agrochemicals and the transport of colloids, thereby increasing the risk for contamination of groundwater resources. The effects of soil compaction, expressed in terms of bulk density (BD), and organic carbon (OC) content on preferential flow and transport were investigated using 150 undisturbed soil cores sampled from 15 × 15–m grids on two field sites. Both fields had loamy textures, but one site had significantly higher OC content. Leaching experiments were conducted in each core by applying a constant irrigation rate of 10 mm h−1 with a pulse application of tritium tracer. Five percent tritium mass arrival times and apparent dispersivities were derived from each of the tracer breakthrough curves and correlated with texture, OC content, and BD to assess the spatial distribution of preferential flow and transport across the investigated fields. Soils from both fields showed strong positive correlations between BD and preferential flow. Interestingly, the relationships between BD and tracer transport characteristics were markedly different for the two fields, although the relationship between BD and macroporosity was nearly identical. The difference was likely caused by the higher contents of fines and OC at one of the fields leading to stronger aggregation, smaller matrix permeability, and a more pronounced pipe-like pore system with well-aligned macropores.

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The present Working Project aims at studying the topic of assurance mapping in a specific organizational context of a Portuguese retail company. For this purpose, an assurance map framework was designed to support the decision making process of stakeholders, through the delivery of comfort concerning risks, operations and control. In the end, the framework was successfully implemented for the process sourcing of goods in two business units of the company. Although, further implementation of the framework proved not to be feasible during the project’s timespan, it is expected to occur in the near future.

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Se propone analizar el efecto del uso productivo en el Chaco Árido de la provincia de Córdoba, mediante la aplicación de indicadores de sustentabilidad relacionados con la calidad de la materia orgánica y la liberación de nutrientes en el suelo, con la finalidad de aportar a un tema de suma interes para la provincia de Córdoba como es la formulación de criterios y pautas de manejo para la implementación de la Ley de Bosques (N° 26331). Se trabajará en la localidad de San Miguel en el departamento Pocho, en un sitio de bosque no disturbado y en tres sistemas productivos: desmonte selectivo con implantación de pasturas; desmonte total con agricultura bajo riego y desmonte total sobrepastoreado. En cada sitio se medirá “in situ” la emisión de CO2 y se tomaran muestras de suelo a las que se les determinará: a) contenido de materia orgánica total (MO), b) contenido de sustancias húmicas (SH), diferenciando ácidos húmicos (AH) y fúlvicos (AF), c) abundancia y actividad de microorganismos nitrificadores y d) propiedades químicas de los AH y AF. Se calcularán los siguientes índices de sustentabilidad a) materia orgánica biodisponible (MOB=MO–SH); b) índice de humificación (IH=SH/MO); c) tipo de humus (TH=AF/AH; d) índice de mineralización de C (IMC=CO2/MO); e) índice de nitrificación (IN=actividad/abundancia); y f) índice de estabilidad de las fracciones humificadas: compuestos aromáticos/ alifáticos. Los datos serán analizados estadísticamente mediante ANOVA y comparación de medias por LSD (P<0.05) y tests multivariados. We proposed analyze the effect of land use in Arid Chaco of Cordoba province, using sustainability indicators related to organic matter quality and nutrient release in soil, with the aim to formulate management criteria for the implementation of the Ley de Bosques (N° 26331) in Córdoba province. The study will be conducted in San Miguel village in Pocho department, in one undisturbed forest site and three productive systems: selective clearing with grass sowing; total clearing with irrigation agriculture and total clearing with overgrazed. In each site "in situ" CO2 emission will be measured and soil samples will be taken, in which the following parameters will be determined: a) total organic matter content (MO), b) humic substances content (SH), in humic acids (AH) and fulvic acids (AF), c) abundance and activity of nitrifier microorganisms and d) chemical properties of AH and AF. The sustainability indexes will be calculated: biodisponible organic matter (MOB=MO–SH); b) humification index (IH=SH/MO); c) humus type (TH=AF/AH; d) C mineralization index (IMC=CO2/MO); e) nitrifying index (IN=activity/abundance); and f) humic fractions stability index: aromatic/aliphatic compounds. The data will be statistically analyzed by ANOVA and the means will be compared by LSD (P<0.05) and multivariate tests.

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Las actividades agropecuarias ejercen diferentes presiones sobre los recursos naturales. Esto ha llevado, en algunas áreas, a un deterioro del suelo que provoca un impacto sobre la sustentabilidad en los sistemas agropecuarios. Para evaluar la degradación del suelo se han propuesto listas de indicadores, sin embargo, se carece de una herramienta metodológica robusta, adaptada a las condiciones edafoclimáticas regionales. Además, existe una demanda de productores e instituciones interesados en orientar acciones para preservar el suelo. El objetivo de este proyecto es evaluar la degradación física, química y biológica de los suelos en agroecosistemas del centro-sur de Córdoba. Por ello se propone desarrollar una herramienta metodológica que consiste en un set de indicadores físicos, químicos y biológicos, con valores umbrales, integrados en índices de degradación, que asistan a los agentes tomadores de decisiones y productores, en la toma de decisiones respecto de la degradación del suelo. El área de trabajo será una región agrícola del centro-sur de Córdoba con más de 100 años de agricultura. La metodología comienza con la caracterización del uso del territorio y sistemas de manejo, su clasificación y la obtención de mapas base de usos y manejos, mediante sensores remotos y encuestas. Se seleccionarán sitios de muestreo mediante una metodología semi-dirigida usando un SIG, asegurando un mínimo de un punto de muestreo por unidad de mapeo. Se elegirán sitios de referencia lo más cercano a una condición natural. Los indicadores a evaluar surgen de listas propuestas en trabajos previos del grupo, seleccionados en base a criterios internacionales y a adecuados a suelos de la región. Se usarán indicadores núcleo y complementarios. Para la obtención de umbrales, se usarán por un lado valores provenientes de la bibliografía y por otro, umbrales generados a partir de la distribución estadística del indicador en suelos de referencia. Para estandarizar cada indicador se definirá una función de transformación. Luego serán ponderarán mediante análisis estadísticos mulivariados e integrados en índices de degradación física, química y biológica, y un índice general de degradación. El abordaje concluirá con el desarrollo de dos instrumentos para la toma de decisiones: uno a escala regional, que consistirá en mapas de degradación en base a unidades cartográficas ambientales, de uso del territorio y de sistemas de manejo y otro a escala predial que informará sobre la degradación del suelo de un lote en particular, en comparación con suelos de referencia. Los actores interesados contarán con herramientas robustas para la toma de decisiones respecto de la degradación del suelo tanto a escala regional como local. Agricultural activities exert different pressures on natural resources. In some areas this has led to soil degradation and has an impact on agricultural sustainability. To assess soil degradation a robust methodological tool, adapted to regional soil and climatic conditions, is lacking. In addition, there is a demand from farmers and institutions interested in direct actions to preserve the soil. The objective of this project is to assess physical, chemical and biological soil degradation in agroecosystems of Córdoba. We propose to develop a tool that consists of a set of physical, chemical and biological indicators, with threshold values, integrated in soil degradation indices. The study area is a region with more than 100 years of agriculture. The methodology begins with the characterization of land use and management systems and the obtaining of base maps by means of remote sensing and survey. Sampling sites will be selected through a semi-directed methodology using GIS, ensuring at least one sampling point by mapping unit. Reference sites will be chosen as close to a natural condition. The proposed indicators emerge from previous works of the group, selected based on international standards and appropriate for the local soils. To obtain the thresholds, we will use, by one side, values from the literature, and by the other, values generated from the statistical distribution of the indicator in the reference soils. To standardize indicators transformation functions will be defined. Indicators will be weighted by mans of multivariate analysis and integrated in soil degradation indices. The approach concluded with the development of two instruments for decision making: a regional scale one, consisting in degradation maps based on environmental, land use and management systems mapping units; and an instrument at a plot level which will report on soil degradation of a particular plot compared to reference soils.

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Los materiales lignocelulósicos residuales de las actividades agroindustriales pueden ser aprovechados como fuente de lignina, hemicelulosa y celulosa. El tratamiento químico del material lignocelulósico se debe enfrentar al hecho de que dicho material es bastante recalcitrante a tal ataque, fundamentalmente debido a la presencia del polímero lignina. Esto se puede lograr también utilizando hongos de la podredumbre blanca de la madera. Estos producen enzimas lignolíticas extracelulares fundamentalmente Lacasa, que oxida la lignina a CO2. Tambien oxida un amplio rango de sustratos ( fenoles, polifenoles, anilinas, aril-diaminas, fenoles metoxi-sustituídos, y otros), lo cual es una buena razón de su atracción para aplicaciones biotecnológicas. La enzima tiene potencial aplicación en procesos tales como en la delignificación de materiales lignocelulósicos y en el bioblanqueado de pulpas para papel, en el tratamiento de aguas residuales de plantas industriales, en la modificación de fibras y decoloración en industrias textiles y de colorantes, en el mejoramiento de alimentos para animales, en la detoxificación de polutantes y en bioremediación de suelos contaminados. También se la ha utilizado en Q.Orgánica para la oxidación de grupos funcionales, en la formación de enlaces carbono- nitrógeno y en la síntesis de productos naturales complejos. HIPOTESIS: Los hongos de podredumbre blanca, y en condiciones óptimas de cultivo producen distintos tipos de enzimas oxidasas, siendo las lacasas las más adecuadas para explorarlas como catalizadores en los siguientes procesos:  Delignificación de residuos de la industria forestal con el fin de aprovechar tales desechos en la alimentación animal.  Decontaminación/remediación de suelos y/o efluentes industriales. Se realizarán los estudios para el diseño de bio-reactores que permitan responder a las dos cuestiones planteadas en la hipótesis. Para el proceso de delignificación de material lignocelulósico se proponen dos estrategias: 1- tratar el material con el micelio del hongo adecuando la provisión de nutrientes para un desarrollo sostenido y favorecer la liberación de la enzima. 2- Utilizar la enzima lacasa parcialmente purificada acoplada a un sistema mediador para oxidar los compuestos polifenólicos. Para el proceso de decontaminación/remediación de suelos y/o efluentes industriales se trabajará también en dos frentes: 3) por un lado, se ha descripto que existe una correlación positiva entre la actividad de algunas enzimas presentes en el suelo y la fertilidad. En este sentido se conoce que un sistema enzimático, tentativamente identificado como una lacasa de origen microbiano es responsable de la transformación de compuestos orgánicos en el suelo. La enzima protege al suelo de la acumulación de compuestos orgánicos peligrosos catalizando reacciones que involucran degradación, polimerización e incorporación a complejos del ácido húmico. Se utilizarán suelos incorporados con distintos polutantes(por ej. policlorofenoles ó cloroanilinas.) 4) Se trabajará con efluentes industriales contaminantes (alpechínes y/o el efluente líquido del proceso de desamargado de las aceitunas). The lignocellulosic raw materials of the agroindustrial activities can be taken advantage as source of lignin, hemicellulose and cellulose. The chemical treatment of this material is not easy because the above mentioned material is recalcitrant enough to such an assault, due to the presence of the lignin. This can be achieved also using the white-rot fungi of the wood. It produces extracellular ligninolitic enzymes, fundamentally Laccase, which oxidizes the lignin to CO2. The enzyme has application in such processes as in the delignification of lignocellulosic materials and in the biobleaching of fibers for paper industry, in the treatment of waste water of industrial plants, in the discoloration in textile industries, in the improvement of food for ruminants, in the detoxification of polutants and in bioremediation of contaminated soils. HYPOTHESIS: The white-rot fungi produce different types of enzymes, being the laccases the most adapted to explore them as catalysts in the following processes:  Delignification of residues of the forest industry in order to take advantage of such waste in the animal feed.  Decontamination of soils and / or waste waters. The studies will be conducted for the design of bio reactors that allow to answer to both questions raised in the hypothesis. For the delignification process of lignocellulosic material they propose two strategies: 1- to treat the material with the fungi 2-to use the partially purified enzyme to oxidize the polyphenolic compounds. For the soil and/or waste water decontamination process, we have: 3- Is know that the enzyme protects to the soil of the accumulation of organic dangerous compounds catalyzing reactions that involve degradation, polymerization and incorporation to complexes of the humic acid. There will be use soils incorporated into different pollutants. 4- We will work with waste waters (alpechins or the green olive debittering effluents.

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Sludge provides valuable nutrients to soil. Application of sludge to land is subject to a number of limitations. Its use as a soil conditioner represents a "beneficial reuse option". Primary and secondary sludge from Dublin city is treated in Ringsend treatment plant where it undergoes thermal drying. This study investigates the feasibility of land application of thermally dried biosolids (TDB) from Ringsend treatment plant.

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Abstract Background: Most international studies on epidemiology of transient loss of consciousness (TLC) were performed many years ago. There are no data about the lifetime prevalence of TLC in Russia. Objective: To identify the lifetime prevalence and presumed mechanisms of TLC in an urban Russian population. Methods: 1796 individuals (540 males [30.1%] and 1256 females [69.9%]) aged 20 to 69 years (mean age 45.8 ± 11.9 years) were randomly selected and interviewed within the framework of multicentre randomised observational trial. Results: The overall prevalence of TLC in the studied population was 23.3% (418/1796), with the highest proportion (28%) seen in 40-49 year age group. TLC was significantly more common in women than in men (27.5% vs 13.5%). The mean age of patients at the time of the first event was 16 (11; 23) years, with 333 (85%) individuals experiencing the first episode of TLC under 30 years. The average time after the first episode of TLC was 27 (12; 47) years. The following mechanisms of TLC were determined using the questionnaire: neurally-mediated syncope (56.5%), arrhythmogenic onset of syncope (6.0%), nonsyncopal origin of TLC (1.4%), single episode during lifetime (2.1%). Reasons for TLC remained unidentified in 34% cases. 27 persons (6.5%) reported a family history of sudden death, mainly patients with presumably arrhythmogenic origin (24%). Conclusion: Our findings suggest that the overall prevalence of TLC in individuals aged 20-69 years is high. The most common cause of TLC is neurally-mediated syncope. These data about the epidemiology can help to develop cost-effective management approaches to TLC.

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As a rule, soils of the subtropical and tropical regions, in which rainfall is not limiting, are acidic, and low in phosphorus, and, to a less extent, in other macro and micronutrients as well, such a sulfur, boron and zinc. The establishment of a permanent agricultural prac. tice therefore, demands relatively high usage of liming and phosphatic fertilization, to begin with. Several approaches, not mutually exclusive, could be used in order to increase the efficiency of utilization of soil and fertilizer phosphorus so that, goal of diminishing costs of production is reached. The use of liming materials bringing up pH to 6.0-6.5 causes the conversion of iron and aluminum phosphates to more available calcium phosphates; on the other hand, by raising calcium saturation in the exchange complex, it improves the development and operation if the root system which allows c or a higher utilization of all soil nutrients, including phosphorus, and helps of stand water deficits which may occur. The role of mycorrhizal fungi should be considered as a way of increasing soil and fertilizer P utilization, as well as the limitations thereof. Screening of and breeding for varieties with higher efficiency of uptake and utilization of soil and fertilizer phosphorus leads to a reduction in cost of inputs and to higher benefit/cost ratios. Corrective fertilization using ground rock phosphate helps to saturate the fixation power of the soil thereby reducing, as a consequence, the need for phosphorus in the maintenance fertilization. Maintenance fertilization, in which soluble phos-phatic sources are used, could be improved by several means whose performance has been proved: limimg, granula tion, placement, use of magnesium salts. Last, cost of phosphate fertilization could be further reduced, without impairing yields, through impairing yields, through changes in technology designed to obtain products better adapted to local conditions and to the availability or raw materials and energy sources.

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Water movement in unsaturated soils gives rise to measurable electrical potential differences that are related to the flow direction and volumetric fluxes, as well as to the soil properties themselves. Laboratory and field data suggest that these so-called streaming potentials may be several orders of magnitudes larger than theoretical predictions that only consider the influence of the relative permeability and electrical conductivity on the self potential (SP) data. Recent work has improved predictions somewhat by considering how the volumetric excess charge in the pore space scales with the inverse of water saturation. We present a new theoretical approach that uses the flux-averaged excess charge, not the volumetric excess charge, to predict streaming potentials. We present relationships for how this effective excess charge varies with water saturation for typical soil properties using either the water retention or the relative permeability function. We find large differences between soil types and the predictions based on the relative permeability function display the best agreement with field data. The new relationships better explain laboratory data than previous work and allow us to predict the recorded magnitudes of the streaming potentials following a rainfall event in sandy loam, whereas previous models predict values that are three orders of magnitude too small. We suggest that the strong signals in unsaturated media can be used to gain information about fluxes (including very small ones related to film flow), but also to constrain the relative permeability function, the water retention curve, and the relative electrical conductivity function.

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A sequence of “inner equations” attached to certain perturbations of the McMillan map was considered in [MSS09], their solutions were used in that article to measure an exponentially small separatrix splitting. We prove here all the results relative to these equations which are necessary to complete the proof of the main result of [MSS09]. The present work relies on ideas from resurgence theory: we describe the formal solutions, study the analyticity of their Borel transforms and use ´Ecalle’s alien derivations to measure the discrepancy between different Borel-Laplace sums.

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Sleep is regulated by a homeostatic process that determines its need and by a circadian process that determines its timing. By using sleep deprivation and transcriptome profiling in inbred mouse strains, we show that genetic background affects susceptibility to sleep loss at the transcriptional level in a tissue-dependent manner. In the brain, Homer1a expression best reflects the response to sleep loss. Time-course gene expression analysis suggests that 2,032 brain transcripts are under circadian control. However, only 391 remain rhythmic when mice are sleep-deprived at four time points around the clock, suggesting that most diurnal changes in gene transcription are, in fact, sleep-wake-dependent. By generating a transgenic mouse line, we show that in Homer1-expressing cells specifically, apart from Homer1a, three other activity-induced genes (Ptgs2, Jph3, and Nptx2) are overexpressed after sleep loss. All four genes play a role in recovery from glutamate-induced neuronal hyperactivity. The consistent activation of Homer1a suggests a role for sleep in intracellular calcium homeostasis for protecting and recovering from the neuronal activation imposed by wakefulness.

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We studied the stool samples of 151 school children in a district of the city of Portoviejo (Ecuador) in order to determine the prevalence and intensity of soil-transmitted helminthiasis (STH) and their relationships with anthropometric indices. The samples were analyzed with the semiquantitative Kato-Katz technique and the intensity of infections was categorized as light, moderate or high according to the thresholds set by the World Health Organization. Prevalence of soil transmitted helmintiasis was 65% (92 out of 141 collected samples), Ascaris lumbricoides was the most common STH (63%) followed by Trichuris trichiura (10%) and hookworm (1.4%). Heavy intensity infections were found in 8.5% of the stool samples, with T. trichiura showing higher worm burdens than A. lumbricoides. Sixteen percent of the children were below the third percentile for weight (wasted), while 27% were below the third percentile for height (stunted). A significant relationship was found between the worm burden and the degree of stunting. This study suggests that the periodic administration of an antihelminthic drug should be targeted to preschool and school children to allow a normal growth spurt and prevent stunting.