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Phillips, Debra Helen. "The genesis of selected podzols and cambisols from the eastern United States and north-east Scotland." Thesis, University of Aberdeen, 1994. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=186012.
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The nature and properties of eight selected Podzols and Cambisols from the eastern United States and north-east Scotland were investigated to determine 1) their pedogenesis from physical, chemical, mineralogical, morphological and micromorphological properties, and 2) soil genesis relationships between the soils. Physical, chemical, mineralogical, morphological and micromorphological analysis were conducted on four soils from each country. The following physical and chemical analyses were conducted: particle size, pH by water, KCl and CaCl2, exchangeable bases, cation exchange capacity (CEC), percent base saturation (BS), KCl extractable H and Al, carbon determination, acid-oxalate extractable Al, Fe, Mn and Si, and dithionite-citrate-bicarbonate (DCB) extractable Al, Fe and Mn. The mineralogy of the very fine sand fraction was determined by grain counts, while energy dispersive x-ray analyses conducted on a scanning electron microscope (SEM-EDXRA) gave details of the composition of coatings, matrix material and other features of selected areas of thin sectors. Petrographic studies of soil thin sections revealed certain micromorphological characteristics and field descriptions gave information on the morphology of the soils. These investigations revealed a wide range of spodic expression in the soil profiles which depended greatly on the combination of parent material, climate, vegetation, relief and time. Of the eight soils studied, six were Podzols and the other two, although having characteristics of Podzols, were classified as Dystric Cambisols. A Carbic Podzol (Georgia) and a Ferric Podzol (New Jersey) both formed in sandy, base deficient coastal plain sediments on flat reliefs at low elevations in the eastern United States.
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Ahmed, Engy. "The interaction between microbes, siderophores and minerals in podzol soil." Licentiate thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-89319.
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Sanborn, Paul Thomas. "Ferro-humic podzols of coastal British Columbia : aspects of genesis and chemistry." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27523.
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Three related aspects of the genesis and chemistry of Ferro-Humic Podzols in coastal British Columbia were investigated: micromorphology, phosphorus forms, and biological aluminum cycling.
Profile morphologies display horizon disruption by slope instability and windthrow, with a patchy distribution of organic matter in the solum. Maximum
C concentrations often occur at the base of the B horizon above a root-restricting layer. Channel-like features formed by root growth and decomposition
provide important hydrologic pathways and may be either strongly enriched
in organic matter (> 17% C) and Al, or partially eluviated.
Microfabrics of surface organic and eluvial horizons resemble those of other forest Podzols. Organic matter-rich zones within B horizons have distinctive
fabrics consisting of amorphous organic materials and/or humified, but recognizable, root detritus. Few living roots occur, suggesting that these features may be relict. Root residues appear to serve as deposition sites of Al and other metals. Such features appear to form through both in situ decomposition and illuviation, with little influence by faunal activity. Bhf horizon fabrics may be dominated by granular aggregates of presumed faunal origin, although with finer textures, microstructures tend to be more blocky. In coarser-textured B horizons, fabrics tend to be dominated by coatings and infillings of organic materials, often with a high proportion of recognizable plant tissue residues.
Extraction data suggest the occurrence of allophanic materials in some B horizons with C contents exceeding 15%, with such cases associated with high Fe concentrations. Complex yellow and red colour banding in void infillings may indicate compositional zonation. A sequential phosphorus extraction and fractionation technique indicated a degree of weathering of primary phosphates comparable to that in Ultisols. Although total P was greatly depleted from eluvial horizons, organic P (Po) was dominant throughout the sola of eight profiles. Bicarbonateextractable Po, thought to be the most labile Po fraction, was more abundant than in many Mollisol A horizons. Correlations suggested a role for this fraction in supplying labile inorganic P in B horizons. Levels of resistant residual P in two regional groups of B horizons were directly related to Fe content. Al, organic matter, and Po levels are directly related in B horizons, suggesting a common illuvial origin.
Annual return of Al in needle litter (approximately 1 kg ha⁻¹) was similar in both western hemlock and Douglas-fir stands. In fresh hemlock needles, much of the Al content is easily leached by dilute neutral salt solutions; comminution increases this extractability. During decomposition, the proportion of pyrophosphate-extractable Al increases, suggesting a shift to organic-complexed forms. Biologically-cycled forms may comprise much of the Al flux in the upper solum, with litter comminution by soil fauna partially controlling the rate of release during decomposition.Land and Food Systems, Faculty of
Graduate
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Holland, Anne E. "Organic lamellae in the eluvial horizons of podzols : a field study of the distribution of a morphological feature in the soil landscape." Thesis, University of Reading, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329721.
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Harguindéguy, Stéphanie. "Transport de l’uranium dans les eaux et le sol : approche combinée colloïdale et isotopique." Thesis, Pau, 2013. http://www.theses.fr/2013PAUU3043/document.
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Les mécanismes d’interactions entre uranium et colloïdes ont été étudiés à partir d’échantillons provenant d’un site d’intérêt pour le Commissariat à l’Energie Atomique (CEA). La mobilisation de l’uranium depuis les sols a été appréhendée par lixiviations statique et dynamique. Le transfert et le transport ont été investis en considérant les eaux de nappe et de surface (drain). Les résultats confirment que l’uranium anthropique est plus mobile que l’uranium naturel. Le comportement (mobilisation, distribution) de l’uranium ne diffère cependant pas selon son origine. La phase colloïdale joue un rôle non négligeable dans la migration dans le sol et le transfert vers les eaux, représentant de 10 à 90 % de l’uranium suivant les échantillons. Les phases porteuses de l’uranium sont dans un continuum de taille allant jusqu’à environ 200 nm de diamètre hydrodynamique. Elles sont principalement composées de matière organique, de fer et d’aluminium. Le long du drain, de l’amont à l’aval du site, un réarrangement des associations colloïdales uranium-matière organique se fait en défaveur de celles uranium-fer, la proportion d’uranium colloïdale lié à l’aluminium restant elle inchangéeMechanisms of interaction between uranium and colloids were studied by samples taken from a site of interest for the “French Nuclear Agency” (CEA). The mobilization of uranium from soils was apprehended by static and dynamic leaching experiments. The transfer and transport have been studied by considering pondwaters and drainwaters. Results confirm that anthropogenic uranium is more mobile than natural uranium. However mechanisms of mobilization and distribution of uranium, does not differ depending on its origin. The colloidal fraction plays an important role on the migration in soil and the transfer into water by representing from 10 to 90 % uranium depending on samples. The colloidal fractions of uranium are in a continuum of size up to about 200 nm hydrodynamic diameter. They are mainly composed of organic material, iron and aluminum. Along the drain, from the upstream to the downstream of the site, rearrangement of colloidal associations between uranium and organic material occurs in disfavor of colloidal associations between uranium and iron, the proportion of colloidal uranium bound to aluminum remains unchanged
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Bravard, Sylvie. "Podzolisation en Amazonie brésilienne : étude d'une séquence sol ferrallitique-podzol de la région nord de manaus." Poitiers, 1988. http://www.theses.fr/1988POIT2326.
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Bravard, Sylvie. "Podzolisation en Amazonie brésilienne étude d'une séquence sol ferralitique-podzol de la région nord de Manaus /." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376123017.
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Ribeiro, João Pedro de Sousa Peres Oliveira. "Aplicação de cinza de biomassa no solo: estudo do perfil e lixiviado." Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/12434.
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Mestrado em Engenharia do AmbienteEstima-se que a produção de cinzas de combustão de biomassa em Portugal ultrapasse, anualmente, as 90.000 toneladas. A sua aplicação no solo é uma possibilidade para a gestão deste subproduto. Por ser geralmente rica nesses elementos, a cinza pode fornecer ao solo nutrientes fundamentais para as plantas, como Ca, Mg, K, P ou Na. Contudo, pode conter igualmente alguns metais pesados, como As, Cd, Zn, Cr, Cu ou Pb. O objetivo deste trabalho é estudar o efeito da aplicação de cinzas no perfil do solo, bem como nos seus lixiviados. Para tal, foram testados, em lisímetros à escala laboratorial, dois tipos de solo: podzol e cambissolo. Foram utilizados, por ensaio, 4 lisímetros, com aplicação de material diferente: cinza; mistura de cinza e lama biológica (50:50), agente de calagem (CaO/CaCO3) e nenhum material, numa coluna de controlo. Os materiais foram aplicados às cargas de 1 ton.ha-1 (cambissolo) e 7,5 ton.ha-1 (ambos). Foi efetuada uma simulação de precipitação diária nos perfis de solo, sendo recolhido o lixiviado. No final do ensaio de lixiviação, os perfis de solo e lixiviados foram sujeitos a extensa análise (pH, CE, distribuição granulométrica do solo, quantificação de nutrientes e metais, etc.). A aplicação de cinza aumentou ligeiramente o pH dos solos, sendo esse efeito mais pronunciado nos lixiviados. Todos os materiais testados provocam aumento de condutividade elétrica quer no solo quer no lixiviado. Quanto ao enriquecimento em nutrientes, os resultados do cambissolo são globalmente melhores do que os do podzol, tendo a cinza provocado efeito em nada inferior ao agente de calagem. O aumento de carga tornou estes resultados mais notórios. A fração de elemento que é mobilizada para o lixiviado é invariavelmente bastante reduzida.
It is estimated that the production of biomass ash in Portugal exceeds 90.000 tons per year. Its application in soils is a possible way of managing this sub-product. Because it is naturally rich in such elements, biomass ash can supply essential nutrients for plant growth, such as Ca, Mg, K, P or Na. Nevertheless, it may as well contain some level of heavy metals, such as As, Cd, Cr, Cu, Zn, Ni or Pb. This thesis’ main goal was to study the effect of the application of biomass ash in the soil profile, as well as in its leachate. To this end, essays were made with four laboratory scale lysimeters, each one receiving a different material: biomass ash, ash combined with sludge (50:50 mix), a buffering agent (CaO/CaCO3), and no material in one lysimeter, which played the role of test control. Two classes of soil have been tested (podzol and cambissol) and two rates of product application have been used: 1 and 7.5 tons per hectare. A simulation of daily natural watering of the tested soils has been made, with collection of the resulting leachate. At the end of the leaching period, leachates and soil profiles were both extensively analyzed (pH, electrical conductivity, particle size distribution, quantification of nutrients and metals, etc.). Biomass ash application slightly elevated soil pH. The effect was superior in leachates. All tested materials produced raises in electrical conductivity, both in soil and leachate. In what nutrient enrichment is concerned, the results obtained for the cambissol were globally better than the ones obtained for the podzol. It has been noticed that the effect produced by the ash has been similarly good in comparison with the buffering agent’s effect. Increasing the application rate, the results tend to improve. The fraction of element that is mobilized in the leachate is invariably minimal.
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Matos, Elisa Rabelo. "Variações das estruturas das comunidades de bactérias e fungos em Espodossolos sob diferentes regimes de drenagem." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11138/tde-05052015-113117/.
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Os Espodossolos são os solos de maior ocorrência na planície costeira do litoral do Estado de São Paulo e são caracterizados pela presença de um horizonte espódico (Bh ou Bhm). Poucas são as informações relacionadas à gênese destes solos em regiões tropicais, assim como da composição química da matéria orgânica (MO) nos mesmos e da influência dos micro-organismos em sua formação. É possível que micro-organismos envolvidos na degradação seletiva da MO sejam importantes para a gênese de Espodossolos, como observado anteriormente em Espodossolos de Bertioga e Ilha Comprida. O primeiro estudo teve como objetivo avaliar a variação espacial da estrutura das comunidades e a abundância de bactérias e fungos em três perfis de Espodossolos sob drenagem intermediária, nos diferentes horizontes e nas manchas brancas através de PCR-DGGE e quantificação por qPCR dos genes rRNA 16S de bactérias e ITS de fungos. O segundo estudo teve como objetivo avaliar a variabilidade espacial das comunidades de bactérias nos horizontes e nas manchas brancas de Espodossolos sob três regimes de drenagem, e determinar se a diversidade genética e estrutura das comunidades de bactérias estão associadas à composição molecular da MO nessas regiões, através do sequenciamento massivo da região V4 do gene do rRNA 16S de bactéria e análise de compostos orgânicos por pirólise-GC/MS. As estruturas das comunidades bacterianas, determinada por PCR-DGGE, nos diferentes horizontes de cada perfil foram mais similares entre si do que nos mesmos horizontes em diferentes perfis de Espodossolos. A estrutura das comunidades fungos não apresentou diferenças significativas, independente da localidade do perfil e profundidade dos horizontes. A abundância de cópias do gene rRNA 16S e região ITS, determinada por qPCR, foi maior no horizonte A do que no horizonte Bh, para os três perfis de Espodossolos estudados. Apesar de não haver diferenças significativas na estrutura das comunidades, grupos específicos de bactérias e fungos podem estar envolvidos na degradação seletiva da matéria orgânica nos diferentes horizontes, bem como nas manchas brancas e suas adjacências. A estrutura das comunidades de bactérias, determinada por sequenciamento massivo do gene rRNA 16S, nos horizontes mais superficiais (A e AE) foi distinta daquela observada nos horizontes mais profundos (EB, BE e Bh). Porém, as comunidades bacterianas nas manchas brancas e suas regiões adjacentes foram mais similares entre si, do que em relação as comunidades bacterianas nos horizontes, em todos os perfis analisados, independente do regime de drenagem. Acidobacteria, Proteobacteria e Actinobacteria foram os filos mais abundantes nos solos estudados. Actinobacteria e Alphaproteobacteria mostraram associação positiva com moléculas orgânicas derivadas da pirólise da lignina, as quais foram mais abundantes nos horizontes superficiais (A e AE), enquanto Acidobacteria mostrou associação positiva com compostos mais recalcitrantes encontrados em horizontes mais profundos (Bh), sugerindo um papel específico e diferenciado de cada grupo bacteriano na degradação de compostos orgânicos específicos. Os resultados desses estudos sugerem que grupos bacterianos específicos podem estar envolvidos na gênese de Espodossolos através da degradação de compostos orgânicos específicos em diferentes horizontes.Podzols are highly frequent soils in the coastal plains of the São Paulo State, and are characterized by the presence of a spodic horizon (Bh or Bhm). Studies on the pedogenetic processes in Podzols of tropical regions are scarce, as well as studies on the molecular characterization of their organic matter (OM) and on the microorganisms involved in their genesis. It is possible that microorganisms involved in the selective degradation of the soil OM are important for the genesis of Podzols, as previously observed in Podzols of Bertioga and Ilha Comprida. The aim of the first study was to evaluate the spatial variation of the community structure and abundance of bacterial and fungi in the different horizons, bleached mottles and their immediate vicinity of three Podzol profiles under intermediary drainage regime, using PCR-DGGE and qPCR of the bacterial rRNA 16S gene and fungal ITS region. The aim of the second study was to determine the spatial variability of the bacterial communities in the horizons and bleached mottles of Podzols under three drainage regimes, and whether the bacterial genetic diversity and community structure were associated to the molecular OM composition, using high-throughput sequencing of the V4 region of the bacterial 16S rRNA gene and analyses of organic compounds by pyrolysis GC/MS. The structure of bacterial communities, determined by PCRDGGE, in the different horizons of each soil profile were more similar to each other than in the same horizons of different soil profiles. The fungal community structures did not show significant differences, independent of the soil profile location and horizons depth. Abundance of copies of the bacterial 16S rRNA gene and fungal ITS region, determined by qPCR, was higher in the A horizon than in the Bh horizon, for the three Podzol profiles studied. Even though there were no significant differences in community structures, specific groups of bacteria and fungi may be involved in the selective degradation of organic matter in different horizons, bleached mottles and their immediate vicinity. The bacterial community structures, determined by highthroughput sequencing of the 16S rRNA gene, in the surface horizons (A and AE) were distinct of that in the deeper horizons (EB, BE and Bh). However, the bacterial community structures in the bleached mottles and their immediate vicinity were more similar to each other than to the community structures in the horizons, in all profiles studied, regardless of the drainage regime. Acidobacteria, Proteobacteria and Actinobacteria were the most abundant phyla in the soils studied. Actinobacteria and Alphaproteobacteria showed a positive relationship organic compounds derived from lignin degradation, which were more abundant in the surface horizons (A and AE), whereas Acidobacteria showed a positive relationship with more recalcitrant compounds detected in deeper horizons (Bh), suggesting a specific and distinct roles of each bacterial group in the degradation of specific organic compounds. The results of these studies suggest that specific bacterial groups may be involved in the genesis of Podzols by degrading specific organic compounds in different horizons.
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Courchesne, François. "Mechanisms regulating sulfate movement in some podzols from Quebec." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75774.
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The reaction of sulfate with six podzolic horizons of the Southern Laurentians (Quebec) was investigated using batch reaction techniques. It was demonstrated that sulfate sorption increased with decreasing solution pH to a maximum sorption capacity at around pH 4.0; below this pH retention decreased. This drop in sorption capacity was related to the partial dissolution of Al surface coatings. Indeed, the amount of native sulfate and the maximum sorption during the experiment were positively correlated (R$ sp2$ = 0.982, 0.800) with the oxalate extractable Al content of these forested soils. In all six horizons, the increase in sulfate sorption as a function of equilibrium sulfate concentration was best described by the Gunary equation. Kinetic experiments showed the presence of two major stages in both sorption and desorption reactions with an initial quick change (first 6 h) in solution concentration being followed by a second step where the reactions between sulfate and the soil matrix were much slower. The time-dependence of these reactions emphasized the appropriateness of kinetic equation in describing field situations. Moreover, kinetics studies performed under highly acidic conditions demonstrated that the amount of sulfate sorbed decreased with time after an initial sorption step due to the partial dissolution of Al surface materials. Thermodynamic calculations further suggested the subsequent precipitation of jurbanite. It was then concluded that surface dissolution and mineral formation should be considered in the interpretation of results obtained from experiments aimed at determining the effect of pH on sulfate retention.
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Ahmed, Engy. "Microbe-mineral interactions in soil : Investigation of biogenic chelators, microenvironments and weathering processes." Doctoral thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-115250.
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The interplay between geology and biology has shaped the Earth during billions of years. Microbe-mineral interactions are prime examples of this interplay and underscore the importance of microorganisms in making Earth a suitable environment for all forms of life. The present thesis takes an interdisciplinary approach to obtain an integrated understanding of microbe-mineral interactions. More specifically it addresses how the composition and distribution of biogenic weathering agents (siderophores) differ with regard to soil horizon and mineral type in situ, what siderophore type soil microorganisms produces under laboratory conditions, what role microbial surface attachment plays in mineral weathering reactions and what central roles and applications siderophores have in the environment. Podzol, the third most abundant soil in Europe, and most abundant in Scandinavia, was chosen for a field experiment, where three minerals (apatite, biotite and oligoclase) were inserted in the organic, eluvial and upper illuvial soil horizons. The study started with an investigation of the siderophore composition in the bulk soil profile and on the mineral surfaces (paper I), which was followed by a study of the siderophore producing capabilities of microorganisms isolated from the soil profile under laboratory conditions (paper II). Subsequently, a study was done on the impact of microbial surface attachment on biotite dissolution (paper III). Finally, the roles of siderophores in nature and their potential applications were reviewed (paper IV). The major findings were that the concentration of hydroxamate siderophores in the soil attached to the mineral surfaces was greater than those in the surrounding bulk soil, indicating that the minerals stimulate the microbial communities attached to their surfaces to produce more siderophores than the microorganisms in the bulk soil. Each mineral had a unique assemblage of hydroxamate siderophores, that makes the mineral type one of the main factors affecting siderophore composition in the natural environment. Siderophore production varied between the microbial species originating from different soil horizons, suggesting that the metabolic properties of microbes in deep soil horizons function differently from those at upper soil horizons. Microbial surface attachment enhanced the biotite dissolution, showing that attached microbes has a greater influence on weathering reactions in soil than planktonic populations. In conclusion, our findings reflected that the complicated relationship between microorganisms and mineral surfaces reinforces the central theme of biogeochemistry that the mineral controls the biological activity in the natural environments. However, the importance of these relationships to the biogeochemical systems requires further investigation.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: In press. Paper 3: In press.
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Munier-Lamy, Colette. "Mobilisation et préconcentration de l'uranium dans les sols : Rôle des substances hymiques." Nancy 1, 1987. http://www.theses.fr/1987NAN10220.
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Crançon, Pierre. "Migration de l'uranium dans un podzol : le rôle des colloïdes dans la zone non saturée et la nappe : application aux landes de Gascogne." Phd thesis, Grenoble 1, 2001. http://www.theses.fr/2001GRE10006.
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L'uranium est fortement associe aux matieres organiques dans de nombreux sols naturels. U(vi) forme plus particulierement des complexes tres stables avec les acides humiques, pour des conditions acides a neutres. Les acides humiques peuvent se rencontrer dans les systemes naturels en agregats avec les argiles, ou en enrobage de particules minerales. Ces structures sont tres sensibles aux variations de la force ionique du milieu. Cette sensibilite peut etre a l'origine d'une forte remobilisation des substances humiques colloidales du sol, et de leur migration en direction de la nappe phreatique. Dans ce cas, la migration de l'uranium complexe par les substances humiques peut etre grandement facilitee dans le sol. Le transport reactif comparatif de l'uranium total et de ses isotopes a ete etudie dans un site ou de l'uranium metallique est repandu a la surface du sol, dans le podzol des landes de gascogne. L'etude de terrain est completee par une etude experimentale en colonnes. L'evolution temporelle de la concentration totale en uranium et des rapports isotopiques u 2 3 5/u 2 3 8 et u 2 3 3/u 2 3 8 est determinee par icp-ms. Le suivi de la concentration relative en substances humiques est realise par fluorescence uv en ligne. L'etude de terrain montre que la majorite de l'uranium est retenue dans les premiers centimetres du sol. On observe pourtant des concentrations en uranium anormalement elevees dans les eaux souterraines, a plus de 2 kilometres a l'aval des zones contaminees. Ceci montre qu'il existe un processus de transport rapide de l'uranium dans la zone insaturee, et que ce processus assure une migration de l'uranium sur de longues distances. Dans le sol sableux des landes, des colloides naturels argilo-humiques migrent a la vitesse de l'eau, mais peuvent etre retardes lorsque la force ionique des eaux souterraines augmente. On montre que l'uranium est fortement associe a la fraction granulometrique fine (< 8m) du sable, et plus particulierement aux colloides composites argilo-humique. Dans les conditions geochimiques stables des colonnes experimentales, plus de 70% de l'uranium est retenu dans les premiers 2 centimetres de sable, meme apres la circulation de 100 volumes d'eau dans la colonne. Ceci montre la forte capacite de retention de l'uranium du sable des landes. L'ajout de colloides naturels a la solution d'injection favorise la migration de l'uranium. Il apparait qu'entre 5 et 15% de l'uranium total injecte dans les colonnes de sable sont transportes par les colloides argilo-humiques a la vitesse de l'eau. L'utilisation de l'isotope u 2 3 3 permet de realiser la distinction entre l'uranium transporte de facon non reactive a travers le sable, et l'uranium derobe depuis les agregats argilo-humiques et les enrobages des grains du sable. Une diminution brutale de la force ionique du milieu durant les essais de transport montre une remobilisation importante de l'uranium depuis le sol. Lorsque l'on considere les relations complexes entre l'hydrologie et la geochimie dans la zone non saturee du sol, il apparait que le transport de l'uranium est controle par : - les contrastes de force ionique et la vitesse elevee des transferts d'eau dans la partie superieure de la zone insaturee, en reponse a l'infiltration transitoire des lames d'eau de pluie, - l'existence d'une stratification d'acidite et d'oxygene dissous dans le sol, qui determine la speciation de l'uranium et l'efficacite de sa sorption a la surface des mineraux et colloides du sol au dessus de la surface libre de la nappe, - les contrastes geochimiques qui apparaissent lors des remontees de la nappe phreatique.
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Crançon, Pierre. "Migration de l'uranium dans un podzol : le rôle des colloïdes dans la zone non saturée et la nappe ; application aux landes de Gascogne." Phd thesis, Université Joseph Fourier (Grenoble), 2001. http://tel.archives-ouvertes.fr/tel-00718590.
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La zone non saturée d'un sol constitue l'interface entre l'atmosphère et la nappe phréatique. Dans le cas de l'apport d'un polluant à la surface du sol, la rapidité des transferts d'eau et le type de mecanisme de transport sont les facteurs critiques qui déterminent l'efficacité de la zone non saturée dans son rôle de barrière de confinement en amont de la nappe phréatique. L'uranium (VI) forme des complexes très stables avec les acides humiques du complexe absorbant dans les sols. Les agrégats du complexe absorbant sont tres sensibles aux variations de la force ionique du milieu . Cette sensibi ite peut-être à l'origine (l'une forte remobilisation des substances humiques colloïdales du sol et de leur migration Dans ce cas, l migration de ll'uranium complexé par les substances humiques peut être grandement facilitée dans le sol. Le transport reactif comparatif de l'Uranium total et de ses isotopes a été etudiéndans un site ou de l'uranium métallique est répandu à la surface du sol. dans le podzol des Landes de Gascogne, L'etude de terrain est complétée par une étude expérimentale de transport en colonne utilisant des techniques de traçage isotopique pour l'uranium . L'étude de terrain montre que la majorité de l'uranium est retenue dans les premiers centimètres du sol. On observe pourtant des concentrations en uranium anormalement élevées dans les eaux souterraines, à plus de 2 kilomètres il l'aval des zones contaminees. Ceci montre qu'il existe un processus de transport rapide de l'uranium dans la zone insaturée, qui assure une migration de l'uranium sur de longues distances. Dans le sol sableux des Landes, des colloïdes naturels argilo~humiques migrent à la vitesse de l'eau, mais peuvent etre retardés lorsque la force tonique des eaux souterraines augmente. On montre que l'uranium est fortement associé à la fraction granulométrique fine (<8um) du sable, et plus particuliérement aux colloïdes composites argilo~humiques. Dans les conditions géochimiques stables des colonnes expérimentales, plus de 70% de l'uranium est retenu dans les premiers 2 centimètres de sable, même après la circulation de 100 volumes d'eau dans la colonne. Ceci montrre la forte capacité de retention de l'uranium du sable des Landes. L'ajout de colloïdes naturels à la solution d'injection favorise la migration de l'uranium. Il apparait qu'entre 5 et 15% de l'uranium total injecté dans les colonnes de sable sont transportés par les colloïdes argilo-humiques à la vitesse de l'eau. L'utilisation de l'isotope 233U permet de réaliser la distinction entre l'uranium transporte de façon non réactive à travers le sable, et l'uranium désorbé depuis les agrégats argilo-humiques et les enrobages des grains du sable. Une diminution brutale de la force ionique du milieu durant les essais de transport montre une remobilisation importante de l'uranium depuis le sol. Lorsque l'on considère les relations complexes entre l'hydrologie et la géochimie dans la zone insaturée du sol, il apparait que le transport de l'uranium est contrôlé : - par les perturbations de force ionique ou (le pH, en réponse à l'intiltration des lames d'eau de pluie dans la partie supérieure de la zone insaturée et aux remontées de la nappe phréatique dans la partie profonde du sol. - par l'existence d'une stratification d'acidité et d'oxygène dissous dans le sol. qui détermine la spéciation de I'uranium et l'efficacité de sa sorption à la surface des minéraux et colloïdes du sol au-dessus de la surface libre de la nappe, par les contrastes géochimiques qui apparaissent lors des remontées de la nappe phreatique.
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Msaky, John Joseph. "Adsorption et desorption du cuivre et du zinc dans les sols." Paris 6, 1987. http://www.theses.fr/1987PA066094.
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Conditions experimentales: effet du rapport masse de terre-volume de solution sur la charge electrique de surface solide. Quand il augmente les quantites adsorbees diminuent. La nature et la concentration des ligands mineraux et organiques ainsi que la forme ionique du milieu influencent l'adsorption du metal. L'adsorption du cu et du zn est differente selon le type du sol, le ph du systeme et la nature du cation competiteur. L'etude de la desorption montre que les metaux, une fois adsorbes, ne sont pas facilement desorbes
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Edsfeldt, Cecilia. "The radium distribution in some Swedish soils and its effects on radon emanation." Doctoral thesis, KTH, Civil and Environmental Engineering, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3204.
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The aim of this study has been to clarify how the radiumdistribution in soils affects the radon emanation. Thedistribution of radium, uranium and thorium has been determinedusing sequential extractions. In the study, soils from twodifferent locations were investigated.
In the first part the applicability of the sequentialextraction method for determining Ra distribution in differentsoil types was investigated, using a simple sequentialextraction method. Sampled soils were clay, sand and till fromthe vicinity of the Stockholm Esker. The main part of Rnemanating Ra was associated with Fe oxides in the soil. Themethods applied provided information about the radon risk ofthe soil, but, inorder to gain more information on theprocesses governing Ra distribution and radon emanation insoils, a more detailed sequential extraction procedure would bedesirable.
The second part consisted of a detailed study of theradionuclide distribution and the geochemistry in a podzolisedglacial till from Kloten in northern Västmanland. A moredetailed sequential extraction procedure was used, and thespecific surface area of samples was measured. Samples weretaken from E, B, and C horizons; radium and thorium wereenriched in the B horizon, whereas uranium had its maximumconcentration in the C horizon. Extractable radium primarilyoccurred in the exchangeable pool, possibly organicallycomplexed, whereas extractable uranium and thorium were mainlyFe oxide bound. Oxide-bound Ra was important only in the Bhorizon. The radon emanation was not correlated with the amountof exchangeable Ra, but instead with the oxide bound Ra.However, the amount of oxide-bound Ra was too small to accountfor all the emanated Rn, thus, exchangeable Ra was interpretedas the main source of emanated Rn. This exchangeable Ra wasmore emanative in the B horizon than in the C horizon. Theexplanation is the larger surface area of the B horizonsamples; the specific surface area appears to be the maingoverning parameter for Rn emanation in this soil. The surfacearea is largely created by the precipitation of amorphous Feoxides, thus, Fe oxides has a significant effect on Rnemanation.
Comparing the two studies, the Stockholm samples had thesame amounts of oxide-bound Fe and surface-bound Ra. Still theradon emanation was much smaller for these samples than in theKloten soil. The amount of organic matter in the B horizon ofthe Kloten soil is however, much larger than the organic mattercontent in the Stockholm samples. It is suggested that thelarge Rn emanation in the B horizon of Kloten is caused by thecombined effect of Fe oxides and organic matter.
The variability of226Ra distribution in soils was also investigated.The226Ra distribution was determined for samples from60-70 cm and 80-90 cm depth, from three adjacent soil profilesin a podzolic glacial till. Ra distributions, and estimationsof Rn risk based on the Ra distributions, of a single soilprofile, are likely to be representative for a similar area,provided that the samples are taken from a sufficientdepth.
KEYWORDS: distribution, emanation, extraction, glacial till,podzol, Ra, radium, radon, Rn, sequential soil, spodosol, Th,thorium, U, uranium, variability
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Chen, Yao-Te [Verfasser], and Egbert [Akademischer Betreuer] Matzner. "Gross N turnover and soil solution chemistry as influenced by fluctuations of soil water potential and water table in a Podzol and a fen soil / Yao-Te Chen. Betreuer: Egbert Matzner." Bayreuth : Universitätsbibliothek Bayreuth, 2012. http://d-nb.info/1019234695/34.
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Belhadj, Brahim Ali. "Influence des constituants alumineux et ferriques non cristallins sur les cycles du carbone et de l'azote dans les sols montagnards acides." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376027521.
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Mansuy, Daniel. "Les granites et la couverture pédologique dans le bassin du rouge rupt : leurs participations au contrôle de l'acidification des eaux (Cornimont-Vosges méridionales)." Nancy 1, 1992. http://www.theses.fr/1992NAN10399.
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Deux principaux types de granites forment le substratum du bassin du rouge Rupt: le granite des crêtes et ses altérites forment des sols brun acides; les granites acides de Bramont-Ventron sont à l'origine de sols ocre podzoliques. Une altération hydrothermale le long de couloirs de fracturations entraine localement une episyenitisation. Une formation superficielle siliceuse le grassin parfois imperméable recouvre ces granites et favorise le développement de sols hydromorphes. L'action conjuguée des formations granitiques et des sols dérivés confère aux eaux de surface des niveaux d'acidification variables: eaux proches de la neutralité pour le granite des crêtes, alors que les granites de Bramont-Ventron sont à l'origine d'une acidification importante. L'accord entre physicochimie des eaux, nature des sols et des granites semble indiquer que l'altération par hydrolyse des espèces minérales du substratum contrôle globalement l'acidification dans le bassin du rouge Rupt. Les épisodes pluvieux sont à l’ origine de crises brutales d'acidification. Elles peuvent être interprétées comme la manifestation des dépôts acides sur le bassin. Certaines anomalies locales dans l'acidification résultent de faits géologiques particuliers (fracturations et episyenitisation dans le bassin du rouge Rupt). Toutes ces observations permettent de proposer une méthodologie pour l'évaluation des risques d'acidification de bassins versants
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Vasyukova, Ekaterina. "Altération chimique des roches et migration des éléments dans la zone boréale (Nord-Ouest de la Russie)." Phd thesis, Université Paul Sabatier - Toulouse III, 2009. http://tel.archives-ouvertes.fr/tel-00410508.
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Cette thèse a pour but d'améliorer notre compréhension des processus d'altération des roches mafiques silicatées, de la spéciation des éléments et de leur migration dans le milieu boréal (bassin versant de la mer Blanche, Nord-Ouest de la Russie). Les objectifs principales du travail sont i) de caractériser et décrire les mécanismes responsables de l'altération chimique et de la formation des minéraux dans la zone subarctique, ii) évaluer le rôle de la lithologie (environnement granitique versus basaltique) dans la spéciation des éléments traces (ET) et la formation des colloïdes organo-minéraux dans les eaux de surface des bassins versants boréaux des hautes latitudes, et iii) révéler la dépendance de la spéciation des ET en fonction du pH de la solution pour prédire des changements éventuels dans la bioaccumulation des éléments dans les eaux naturelles à cause de leur acidification. L'originalité de cette thèse est de combiner, pour la première fois sur les mêmes objets naturels, les techniques physico-chimique, minéralogique et isotopique afin de mieux comprendre les facteurs qui contrôlent les cycles biogéochimiques des éléments dans les régions subarctiques.
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Gomes, Rossin Bruna. "Estudo das substâncias húmicas em pedo-paisagem podzolizada na bacia do Alto Rio Negro- AM, Brasil." Thesis, Toulon, 2017. http://www.theses.fr/2017TOUL0022.
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Le but de cette étude était de comprendre le comportement des fractions d'acide fulvique et d'acide humiquedans un système de sols podzolisé, compte tenu des caractéristiques du sol et d'étudier la capacité decomplexation de Cu+ 2 et Al + 3 dans des échantillons de ces sols. Pour cela, les méthodes conventionnellesde pédologie et de Spectroscopie de l'absorbance UV-Visible, Spectroscopie Infrarouge à Transformée deFourier et Fluorescence Quenching avec le traitement CP / PARAFAC ont été utilisés pour atteindre lesobjectifs suivants: (i) déterminer les étapes de transformation du pedo-paysage à l'étude des sols et à larépartition spatiale des sols podzols et du gleysol dans un bassin hydrographique; (ii) caractériser substanceshumiques et comprendre les schémas de distribution des acides fulviens et humiques dans une séquence desol podzols le long des profils et dans les horizons du sols en tenant compte des caractéristiquesmorphologiques, de la texture, du pH, carbone variation totale et souterraine dans les horizons des solsd'une séquence de sols podzols; (iii) étudier la capacité de complexation des substances humiques (acidesfulviques et humiques) des échantillons de sol de podzols dans le bassin du Alto Rio Negro, en identifiantles composants fluorescents des substances humiques, en évaluant les capacités et les constantescomplexantes de ces substances avec les métaux Cu+ 2 et Al+ 3 et la comparaison avec les groupesfonctionnels avec la fluorescence infrarouge à transformée de Fourier (FTIR). Encore les acides fulviquessoient plus aromatiques et condensés, leur caractère est principalement aliphatique et hydrophile etsecondairement aromatique et carboxylique. Les acides humiques sont moins aromatiques et moinscondensés que les acides fulviques et sont caractérisés par des fonctions polysaccharide et éther/alcool,mais secondairement leur caractère est aliphatique et hydrophile. Ces différences sont associées à laprésence des groupes fonctionnels qui répondent aux différences dans la dynamique de complexation desmétaux, dans les complexes acide humique, la complexation des métaux Cu+ 2 et Al+ 3 est associée auxfonctions ether/alcool et CO, polysaccharides pendant la période acide fulvic la corrélation est la plus élevéeavec les groupes fonctionnels -CH, -OH et COOH carboxyliqueThe purpose of this study is understaning the behavior of fulvic and humic acid fractions in a podzolized soilssystem, taking into account soils characteristics and to investigate the complexing capacity of Cu + 2 and Al + 3.For this purpose, conventional pedology and spectroscopic methods, Uv-Visible absorbance Spectroscopy, FourierTransform Infrared Spectrometry (FTIR) and Quenching Fluorescence using the CP/PARAFAC treatment wereused to achieve the objectives: (i) to determine the stages of transformation of the pedo-landscape through thestudy of soils and the spatial distribution of podzolized soils and gleysol in a drainage basin; (ii) to characterize SHand to understand the distribution patterns of fulvic and humic acids in a podzolized soil sequence along a slopeand in the horizons along the soil profiles taking into account the morphological characteristics, texture, pH, carbontotal and groundwater variation in the horizons of the soils of a sequence of podzols soils; (iii) to study thecomplexing capacity of humic substances (fulvic and humic acids) of podium soils samples in the Alto Rio NegroBasin, by identifying the fluorescent components of humic substances, evaluating capacities and complexingconstants of these substances with the Cu + 2 and Al + 3 metals, and the comparison with the functional groupsobtained with FTIR. Although fulvic acids are more aromatic and condensed their character is predominantlyaliphatic and hydrophilic and secondarily aromatic and carboxylic. Humic acids are less aromatic and lesscondensed than fulvic acids and are characterized by polysaccharide and ether/alcohol functions, but secondarilytheir character is aliphatic and hydrophilic. These differences are related to the presence of the functional groupsthat are responsible for the differences in the complexation dynamics of the metals, in the humic acids complexesCu+ 2 and Al+ 3 are associated with the functional groups ether/alcohol and CO polysaccharides while in the fulvicacids the correlation is greatest with the functional groups -CH, -OH and carboxylic COOH
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Olofsson, Madelen. "On the investigation of chemical parameters reflecting microbial activity linked to nutrient availability in forest soil." Doctoral thesis, Mittuniversitetet, Avdelningen för naturvetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-25994.
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As agrarian society developed, the most fertile soils able to sustain the nutritional requirements needed for high crop yield were assigned to farming, while the more penurious soils were left to uphold the forest ecosystems. Some temperate forests are developed on acidic soils considered to be nutrient poor, as much of the inorganic nutrients are entrapped in poorly weatherable soil minerals and not easily accessed by plant roots. In an undisturbed ecosystem, the largest contribution of available nutrients comes from the recycling of organically bound nutrients via the decomposition of dead plant material. If biomass is removed, for instance with a more intensified exploitation of the forest ecosystems including whole tree harvesting, this source of nutrients is consequently decreased. The importance of soil mineral weathering as a source of nutrients, and especially that promoted by soil biota, is thereby emphasized. This thesis addresses biotic parameters associated with mineral weathering. Different aspects of soil solution sampling strategies and analysis of different organic ligands as well as biomarkers for the estimation of fungal biomass were investigated. These chemical parameters were also evaluated as indicators of microbial activity in relation to mineral nutrient availability in soil. With the assumption that the current nutrient status of a soil will affect the microbial interest of certain minerals as sources of inorganic nutrients, a mineral amendment trial was performed in a Swedish boreal forest soil. Overall, the amended soil presented good nutrient status, but with a possible shortage of iron. Due to this, it was hypothesized that the amended mineral with the highest iron content i.e. biotite would cause an elevation of microbial activity in its vicinity when compared to the bulk soil. The level of microbial activity in the vicinity of the amended minerals was evaluated via quantification of organic acids and siderophores, as well as estimation of fungal biomass and enzymatic activity. The highest microbial activity was measured for the O horizon of the investigated podzol, although nothing indicated an elevated association with the amended minerals. In the E horizon, however, elevation in microbial activity was observed in the vicinity of the biotite mineral when compared with bulk soil, although only a few of the investigated parameters differed significantly when evaluated separately. To enable this study, a highly sensitive analytical method employing liquid chromatography and mass spectrometry was developed to quantify a number of hydroxamate siderophores. On-line pre-concentration enabled detection of these organic ligands in the pico-molar range – a necessity when analyzing natural samples. Furthermore, an analytical method was developed for the estimation of fungal biomass via quantification of chitin-derived glucosamine, which also employed liquid chromatography and tandem mass spectrometry. Unlike currently available methods, the one presented in this thesis did not involve analyte derivatization, which resulted in high sample throughput while simultaneously avoiding complications involved with the additional derivatization procedure. The distribution of a group of organic ligands known as aromatic low molecular mass organic acids was also studied in a boreal forest podzol soil. Different sampling and samples preparation techniques, namely tension-lysimeters, soil centrifugation and liquid-soil extraction, were compared when analyzing soil solution components. Significant differences in analyte amount and species type were found between these sampling techniques. Some of the differences could be accounted for by variation in soil composition at different depths of the investigated podzol, but others could be attributed to structural differences within the studied analyte group. This clearly illustrated the intricacy of sampling and analysis when working with a sample matrix as complex and diverse as soil. As previously, liquid chromatography and mass spectrometry was used to quantify the analytes of interest. A highly sensitive analytical method was developed that was able to detect eleven aromatic low molecular mass organic acids in the nano-molar range. High selectivity was ensured by applying multiple reaction monitoring enabled by collision induced fragmentation of the analytes.FORE
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Vidal, David. "Evaluations sylvicole et environnementale d’un itinéraire forestier incluant la culture d’un sous-bois fixateur d’azote : Expérimentations in situ de longue durée dans les Landes de Gascogne." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0240.
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L’extraction croissante de la biomasse des forêts cultivées peut impacter la fertilité des sols, par des exports soutenus de nutriments. Parmi eux, l’azote est l’un des éléments qui limitent le plus la croissance des forêts dans le monde. La disponibilité en azote joue donc un rôle clé dans le maintien ou l’augmentation de la productivité sylvicole, et fait ainsi apparaître la fertilisation comme une pratique potentiellement utile. Pour se prémunir des effets néfastes de la fertilisation chimique sur l’environnement, il est un usage alternatif issu de l’agroécologie, qui consiste à intégrer des espèces fixatrices d’azote dans les cultures. Cette solution écologique a été éprouvée avec de nombreux succès en peuplements mixtes forestiers combinant des arbres fixateurs et non-fixateurs. Cependant, l’usage d’un sous-bois fixateur au sein d’un peuplement forestier relève encore aujourd’hui de l’innovation technique et reste ainsi largement à étudier. L’objectif général de la thèse était d’enrichir nos onnaissances sur le fonctionnement d’un écosystème forestier intensivement géré en milieu oligotrophe qui inclue l’utilisation d’un sous-bois fixateur d’azote. Nous nous sommes pour cela concentrés sur l’étude des interactions biotiques et des cycles biogéochimiques des nutriments dans une jeune culture de pins maritimes (essence de production) en forêt des Landes de Gascogne, dont le sous-bois a été cultivé en ajoncs d’Europe (plante fixatrice). Nous nous sommes parallèlement appliqué à déterminer si localement la culture du sous-bois pouvait maintenir, voire augmenter la production forestière. Des essais forestiers, correspondant à différents stades d’avancement de l’itinéraire sylvicole testé, ont été conduits en plein champ avec des itinéraires conventionnels. Dans un premier temps, la culture du sous-bois de légumineuses augmente la compétition pour la lumière et l’eau sur les arbres. Avant l’âge de 3–4 ans, la compétition pour la lumière conduit les pins à une allocation préférentielle de la croissance pour la hauteur de tige, aux dépends de la croissance en diamètre. Avant 4–5 ans, la compétition pour la ressource en eau augmente la mortalité des pins, et diminue leur potentiel hydrique et leur conductance stomatique lors des épisodes de sécheresses estivales. Cependant, la nutrition en azote des pins est améliorée et aucune compétition pour les nutriments, tel que le phosphore, n’est visible. Suite au broyage du sous-bois, intervenant aux alentours de 5–6 ans, les pins compensent la perte de production sur 2 ans, grâce à la levée de la compétition interspécifique et à une fertilisation continue en azote, soutenue par la minéralisation du broyat d’ajonc. Plus généralement, la conduite de l’itinéraire sylvicole améliore la fertilité en azote et le stockage en carbone du sol, et aucune pollution en nitrate n’est à déplorer. La poursuite des études en cours sera nécessaire pour mettre en évidence un éventuel gain de production sylvicole à plus long terme. Localement, nous recommanderions aux gestionnaires forestiers, dans le cas où l’ajonc serait présent en quantité importante, de retarder de quelques années le premier broyage du sous-bois. Des essais dans des écosystèmes comparables pourraient ouvrir de nouvelles possibilités d’application vers d’autres régions forestières et permettre la poursuite des recherches sur le fonctionnement écologique des associations sylvicoles avec des sous-bois fixateurs d’azoteThe increase in extraction of biomass from cultivated forests could negatively affect soil fertility because of high nutrient exportations. Nitrogen, an essential nutrient, is one of the most limiting factors for global forest growth. Therefore, soil nitrogen availability plays a key role in the stability or the increase in forest productivity, and suggests that fertilisation would be a necessary practice. However, in order to avoid the environmental concerns associated with the use of chemical fertilisers, an alternative coming from agroecology could integrate nitrogen-fixing species into the cropping system. This ecological option was successfully applied in forestry in mixed tree plantations associating nitrogen-fixing trees with non-fixing trees. Nevertheless, the innovating technic using nitrogen-fixing shrubs as an intercrop in forestry has to be further studied. The overarching objective of the thesis consists in improving our knowledges about the functioning of intensively managed forest ecosystems including fixing species in oligotrophic soil. To do that, we studied biotic interactions and nutriments biochemical cycles in a young maritime pine plantation (production tree), intercropped with European gorse (nitrogen-fixing species), in the Landes de Gascogne region (SW of France). We also assessed whether a gorse intercropping could maintain or increase the forest production in this forest range. Several forest trials, corresponding to various growth stages of the tested forest itinerary, were conducted in the field with conventional itineraries. Results showed that gorse understorey growth increases both light and water competition with pine. Light competition occurs in the first three to four years after trial installation, with for pine a preferential growth allocation to stem height, at the expense of diameter growth. Competition for water occurs prior to four to five years, with an increase in pine mortality and a decrease in pine water potentials during drought events in summer. However, the pine nitrogen content is increased and competition for soil nutrients, such as phosphorus, is absent throughout this time. After understorey crushing, carried out around five to six years, pines recover the production delay in two years. This is due both to an alleviation of the interspecific competition from the gorse and to a lasting nitrogen fertiliser effect, sustained by the mineralisation of crushed gorse plant material. More precisely, this mixing technique promotes nitrogen fertility and carbon storage in soil, without subsequent nitrate pollution. Further studies will be needed to show a possible gain for forestry production in the longer term. At a local scale, we recommend managers to delay the first understorey control in the case of an abundant gorse understorey. Trials in similar ecosystems could create new opportunities to apply this fertilisation technique in other forest regions
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Zapletal, Aleš. "Podzim jara." Master's thesis, Vysoké učení technické v Brně. Fakulta výtvarných umění, 2015. http://www.nusl.cz/ntk/nusl-232452.
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Müller, Stanislav. ""Podzim oficiálního umění"." Master's thesis, Vysoké učení technické v Brně. Fakulta výtvarných umění, 2010. http://www.nusl.cz/ntk/nusl-232276.
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Hašková, Kristýna. "Podvod a audit." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-142209.
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This thesis deals mainly with internal fraud. In the first section, a definition of fraud is mentioned. The second section briefly describes the internal and external fraud and provides their basic structure. The third section deals with the reasons for committing fraud. The fourth section is concerned with the specific forms of internal fraud which come under the basic groups of corruption, misappropriation of assets and statements manipulation and other forms of fraud which may be between the internal and external fraud. The last section provides examples of large and small accounting examples relating to the internal fraudulent activities.
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Hruška, Tomáš. "Podvod a audit." Master's thesis, Vysoká škola ekonomická v Praze, 2015. http://www.nusl.cz/ntk/nusl-201708.
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The aim of this Master´s Thesis is to introduce fraudulent schemes within organizations and suggest possible actions to prevent this unjust behaviour that negatively affects not only organizations themselves, but also society as a whole. Audit, which is described in the first chapter, plays a major part in preventing fraud. The evolution of audit is described there as well as its main divisions consisting of external, internal and forensic audit, which is important for the investigation of fraud. Second chapter describes fraud as itself, dividing it into external and, more common, internal fraud, which is divided into corruption, asset misappropriations and financial statement fraud. This chapter also contains cybercrime, which is increasingly relevant nowadays. Detailed fraud statistics put together profile of the typical fraudster. Third chapter describes some real fraud cases within business practice. It contains four fraud cases, namely those in companies Enron, Toshiba, Target and Czech corruption scandal concerning former politician David Rath.
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Pickert, Enrico, and Tatjana Bräutigam. "Steckbrief Podsol aus Sandstein: Böden der Berg- und Hügelländer." Sächsisches Landesamt für Umwelt, Landwirtschaft und Geologie (LfULG), 2017. https://slub.qucosa.de/id/qucosa%3A74420.
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Der Steckbrief informiert über den ˈPodsol aus Sandsteinˈ. Der ˈPodsol aus Sandsteinˈ zählt zur Bodenklasse der ˈBöden der Berg- und Hügelländerˈ. Er stellt eine typische Bodenform in Sachsen dar. Er ist ein nährstoffarmer Boden, der sich typisch in der ˈBodenregion der Berg- und Hügelländer mit hohem Anteil an nichtmetamorphen Sand-, Schluff-, Ton- und Mergelsteinenˈ entwickelt hat. Podsole sind nährstoffarme Böden, die sich durch Verlagerungsprozesse und teilweise Wiederausfällung von Fe, Al, und weiteren Elementen zusammen mit organischen Stoffen auszeichnen und dadurch im oberen Profilteil extrem verarmt sind. Der Steckbrief richtet sich an alle Interessierte, die sich über die Entstehung Verbreitung und das Erscheinungsbild typischer, repräsentativer Böden Sachsens informieren möchten.
Redaktionsschluss: 01.03.2017
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White, Catherine Caroline. "Effects of atmospheric deposition on Scottish upland moorland podzols." Thesis, University of Aberdeen, 1996. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU543515.
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Soil samples were collected from the major horizons of Scottish upland Calluna moorland podzols derived from quartzite, Devonian and Torridonian sandstone, or granite or granitic tills. All soil was subjected to routine chemical analysis and the soil derived from granite was also mineralogically analysed. The results were studied in relation to finding evidence for potential acidification effects of atmospheric deposition. Strong relationships were observed between acid deposition parameters, particularly the mobile anion concentrations, and soil pH measured in water and soil extractable Al in all the horizons from podzols derived from sandstones and quartzites. These are discussed in Chapter 2. When looking for ameliorative effects, less clear trends were observed between atmospheric base cation inputs and soil "damage" parameters, possibly due to the distribution of the data. Soils derived from granite or granitic till showed relationships between soil pH in water or in CaCl2 pastes and H+ deposition, and between soil extractable Al and H+ deposition (Chapter 3). In addition, atmospheric inputs of base cations showed strong acid ameliorative properties in these soils. The relative importance of marine- and non-marine base cations in the calculation of critical loads for soil is examined in Chapter 4. The accumulation of N in the surface horizons along a pollution gradient is discussed in Chapter 5. At low to moderate total and NH4+ deposition (i.e., 10 and 5 kg ha-1 yr-1 respectively), soil total N and soil C:N ratio increased linearly with atmospheric N deposition. In spite of the N accumulation, C accumulated relatively faster than N, to increase the C:N ratio at sites with low to moderate N deposition. At total N or NH4+ deposition values above 8.8 and 4.0 kg ha-1 yr-1 respectively, the C:N ratio declined with increasing N deposition.
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Grand, Stephanie. "Reactive soil components and logging in Podzols of southwestern British Columbia." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/35975.
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This study investigated soil characteristics and response to logging in a forested watershed of coastal British Columbia (Roberts Creek Study forest). We focused on soil organic carbon (SOC), labile and exchangeable elements, and short-range order (SRO) inorganic phases. These soil attributes were investigated in each pedogenic horizons (FH, Ae, Bf1, Bf2, BC, Cg) of 27 soil profiles. The profiles formed a disturbance chronosequence including undisturbed (control) forested sites, recently logged (cleared) sites harvested 1 to 5 years prior to sampling, and older logged (regenerating) sites harvested 8 to 15 years prior to sampling.
Soils were coarse-textured humo-ferric Podzols developed on a glacial till underlain by granodioritic bedrock. We found that the average soil profile stored approximately 15.9 kg C / m2 over a depth of 1 m. Over 60% of the profile’s SOC was found at depth greater than 20cm. Predictors of SOC concentration included pyrophosphate and oxalate-extractable Al and Fe and the clay content.
The forest floor of logged plots stored more C than undisturbed plots, most likely due to the addition of logging slash decay products. In the mineral subsoil, SOC was higher in cleared plots and similar to control levels in regenerating plots. This suggests that logging resulted in SOC gains to the mineral soil, but that these inputs were not stabilized. The subsoil played a key role in the overall response of SOC storage after logging and must therefore be taken into consideration in C dynamics studies.
Short-range order inorganic phases such as imogolite-type material and ferrihydrite were a major component of the soil reactive fraction and were estimated to represent approximately 45% of clay-sized subsoil component. The major constituent of SRO phases was likely low-crystallinity proto-imogolite.
Exchangeable ions and nutrients concentration were relatively constant in logged and control plots, with the exception of nitrate. Overall, the impacts of logging were not severe. We hypothesize that the good retention of SOC stores in logged plots and the presence of SRO material in lower mineral horizons contributes to the retention of nutrients in the profile and reduces the ecological effects of forest disturbance.
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Smith, Daniel Robert. "Soil respiration in a fire scar chronosequence of Canadian boreal jack pine forest." Thesis, University of Leicester, 2009. http://hdl.handle.net/2381/8268.
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This research investigates soil respiration (Rs) in a boreal jack pine (Pinus banksiana Lamb.) fire scar chronosequence at Sharpsand Creek, Ontario, Canada. During two field campaigns in 2006 and 2007, Rs was measured in a chronosequence of fire scars in the range 0 to 59 years since fire. Mean Rs adjusted for soil temperature (Ts) and soil moisture (Ms) (Rs T,M) ranged from 0.56 μmol CO2/m2/s (32 years post fire) to 8.18 μmol CO2/m2/s (58 years post fire). Coefficient of variation (CV) of Rs adjusted for Ts and Ms ranged from 20% (16 years post fire) to 56% (58 years post fire). Across the field site, there was a significant exponential relationship between Rs adjusted for soil organic carbon (Cs) and Ts (P = 1.24*10-06; Q10 = 2.21) but no effect of Ms on Rs adjusted for Cs and Ts for the range 0.21 to 0.77 volumetric Ms (P = 0.702). Rs T,M significantly (P = 0.030) decreased after burning mature forest, though no significant (P > 0.1) difference could be detected between recently burned and unburned young forest. Rs was measured in recently burned boreal jack pine fire scar age categories that differed in their burn history and there was a significant difference in Rs T,M between previously 32 v 16 year old (P = 0.000) and previously 32 v 59 year old (P = 0.044) scars. There was a strong significant exponential increase in S R T,M with time since fire (r2 = 0.999; P = 0.006) for the chronosequence 0, 16 and 59 years post fire, and for all these age categories, Rs T,M was significantly different from one another (P < 0.05). The Joint UK Land Environment Simulator (JULES) was used to model vegetation re-growth over successional time at Sharpsand Creek, though it appeared to perform poorly in simulating leaf area index and canopy height. JULES probably over estimated heterotrophic Rs at Sharpsand Creek when Ts corrected simulated values were compared with measured Rs T,M. The results of this study contribute to a better quantitative understanding of Rs in boreal jack pine fire scars and will facilitate improvements in C cycle modelling. Further work is needed in quantifying autotrophic and heterotrophic contributions to soil respiration in jack pine systems, monitoring soil respiration for extended time periods after fire and improving the ability of JULES to simulate successional vegetation re-growth.
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Lopes, Josiane Millani. "Podzols of Ilha Comprida (SE, Brazil): organic matter chemistry and decay features." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-03052016-185358/.
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The most frequent soils in the São Paulo State Coastal Plain are Podzols, characterized by strong to moderate hydromorphic to well-drained podzolization with very well developed podzol-B horizons (Bh or Bhm). Podzolization processes include the effects of hydrology and rooting on profile morphology and the subsequent effects of improved drainage. A Podzol chrono-hydrosequence was described in detail on a cliff at the south coast of Ilha Comprida, a Holocene barrier island, and allowed a subdivision into four distinct groups: poorly-drained profiles, profiles with well-drained B horizons, strongly rooted profiles and superposed profiles. The morphological description and some observations about the exposure cliff were essential for grouping and differentiating the podzol profiles. Some well-drained podzols have OM-depleted mottles that are related to selective decomposition of organic matter (OM) by microorganisms. Such mottles are frequently associated to root channels. Seventeen profiles were studied, thirteen had depletion mottles scattered along the profile. Most of these mottles are whitish and are located preferentially in the horizons of transition between the E and B horizons, particularly in conditions of good drainage. Such mottles have certain morphological differences and may be grouped according to similarities in their morphology and their position in the profile. Distinct groups are: (a) concentric OM-depleted mottles; (b) circular/tubular OM-depleted mottles (burrows); (c) dotted OM-depleted mottles; (d) ghost OM-depleted mottles; (e) irregular OM-depleted mottles and (f) Fe-depleted mottles. The chemical composition of soil organic matter was studied in detail using pyrolysis in combination with gas chromatography/mass spectrometry (Py-GC/MS). Samples of all horizons of the distinct profiles studied were taken, as well as from the center of the mottle (M) and from the direct surroundings (S). The processes involved in the genesis of Podzols in the sandy coastal plain are directly related to drainage, the contribution of dissolved organic matter (DOM), the contribution of organic matter derived from roots, the chemical composition of organic matter and its decomposition by microorganisms, causing a large variation in adjacent Podzols. The well-drained Podzols differ in characteristics from the poorly drained ones in composition and deposition of OM, as well as its decomposition, which is directly related to the activity of groups of microorganisms. They also differ in the relative contribution of OM-derived from roots and DOM. There is a wide variation in the characteristics of decomposition by microorganisms between the profiles of Podzols permanently exposed to air and marine spray (the cliffs) on Ilha Comprida and those inland (pits). There are therefore two main processes that change the morphology of Podzols (OM and composition): (a) change in drainage and rooting, and (b) exposure to air.Os solos mais frequentes na Planície Costeira do Estado de São Paulo são os podzóis, caracterizados por podzolização com hidromorfismo forte a moderado a bem drenado com horizontes B-podzol muito bem desenvolvidos (Bh ou Bhm). O processo de podzolização inclui os efeitos da hidrologia e do enraizamento no perfil e os efeitos subsequentes da drenagem melhorada. Uma crono-hidrosequencia de podzóis foi descrita em detalhes em um barranco na costa sul da Ilha Comprida, uma ilha barreira do Holoceno, e permitiu uma subdivisão em quatro grupos distintos: perfis mal drenados, perfis com horizonte B bem drenados, perfis fortemente enraizados e perfis superpostos. A descrição morfológica e algumas observações sobre o barranco exposto foram essenciais para o agrupamento e diferenciar os perfis de podzóis. Alguns desses podzóis bem drenados possuem manchas esbranquiçadas que estão relacionadas com a seletiva decomposição da matéria orgânica (MO) por microorganismos. Tais manchas são freqüentemente associadas aos canais radiculares. Foram estudados dezessete perfis, dos quais treze apresentaram manchas de esgotamento espalhadas ao longo do perfil. A maioria destas manchas são esbranquiçadas e estão localizadas preferencialmente nos horizontes de transição entre os horizontes E e B, particularmente em condições de boa drenagem. Tais manchas possuem algumas diferenças morfológicas e puderam ser agrupadas de acordo com semelhanças na sua morfologia e da sua posição no perfil. Os grupos são: (a) manchas concêntricas de depleção da MO; (b) manchas circulares/tubularess de depleção da MO (tocas); (c) manchas pontilhadas de depleção da MO; (d) manchas fantasmas de depleção da MO; (e) manchas irregulares de depleção da MO; e (f) manchas de depleção de Fe. A composição química da matéria orgânica do solo foi estudada em detalhe por pirólise em combinação com cromatografia em fase gasosa/espectrometria de massa (Py-CG/EM). Amostras de todos os horizontes dos perfis estudados foram coletadas, bem como amostras do centro das manchas (M) e do solo adjacente (S). Os processos envolvidos na gênese de podzóis da planície costeira arenosa estão diretamente relacionados com a drenagem, a contribuição de matéria orgânica dissolvida (MOD), a contribuição de matéria orgânica derivada de raízes, a composição química da matéria orgânica e sua decomposição por microorganismos, causando uma grande variação no podzóis. Os podzóis bem drenados diferem em características dos mal drenados em composição e deposição de MO, bem como a sua decomposição, que está directamente relacionada com a actividade dos grupos de microrganismos. Eles também diferem na contribuição relativa da MO derivada de raízes e MOD. Existe uma grande variação nas características da decomposição por microorganismos entre os perfis de podzóis permanentemente expostas ao ar e spray marinho (falésias) na Ilha Comprida e os do interior (trincheiras). Há, portanto, dois processos principais que alteram a morfologia de podzóis (composição da MO): (a) mudança na drenagem e enraizamento, e (b) a exposição ao ar.
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Pereira, Osvaldo José Ribeiro. "Mapping soil organic carbon storage in deep soil horizons of Amazonian Podzols." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/64/64135/tde-14062016-113621/.
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The Podzols of the world are divided into intra-zonal and zonal according to then location. Zonal Podzols are typical for boreal and taiga zone associated to climate conditions. Intra-zonal podzols are not necessarily limited by climate and are typical for mineral poor substrates. The Intra-zonal Podzols of the Brazilian Amazon cover important surfaces of the upper Amazon basin. Their formation is attributed to perched groundwater associated to organic matter and metals accumulations in reducing/acidic environments. Podzols have a great capacity of storing important amounts of soil organic carbon in deep thick spodic horizons (Bh), in soil depths ranging from 1.5 to 5m. Previous research concerning the soil carbon stock in Amazon soils have not taken into account the deep carbon stock (below 1 m soil depth) of Podzols. Given this, the main goal of this research was to quantify and to map the soil organic carbon stock in the region of Rio Negro basin, considering the carbon stored in the first soil meter as well as the carbon stored in deep soil horizons up to 3m. The amount of soil organic carbon stored in soils of Rio Negro basin was evaluated in different map scales, from local surveys, to the scale of the basin. High spatial and spectral resolution remote sensing images were necessary in order to map the soil types of the studied areas and to estimate the soil carbon stock in local and regional scale. Therefore, a multi-sensor analysis was applied with the aim of generating a series of biophysical attributes that can be indirectly related to lateral variation of soil types. The soil organic carbon stock was also estimated for the area of the Brazilian portion of the Rio Negro basin, based on geostatistical analysis (multiple regression kriging), remote sensing images and legacy data. We observed that Podzols store an average carbon stock of 18 kg C m-2 on the first soil meter. Similar amount was observed in adjacent soils (mainly Ferralsols and Acrisols) with an average carbon stock of 15 kg C m-2. However if we take into account a 3 m soil depth, the amount of carbon stored in Podzols is significantly higher with values ranging from 55 kg C m-2 to 82 kg C m-2, which is higher than the one stored in adjacent soils (18 kg C m-2 to 25 kg C m-2). Given this, the amount of carbon stored in deep soil horizons of Podzols should be considered as an important carbon reservoir, face a scenario of global climate changeOs Espodossolos podem ser divididos em zonais e intrazonais de acordo com área onde ocorrem. Os Espodossolos zonais são típicos de áreas boreais e taiga, delimitados por condições climáticas. Já os intrazonais não são condicionados pelo clima. Os Espodossolo intrazonais brasileiros ocupam uma grande extensão da alta bacia amazônica, tendo sua formação atribuída à ocorrência de lençóis freáticos suspensos associados à acumulação de complexos organometálicos em ambientes ácidos redutores. Esses solos tem a capacidade de estocar grandes quantidades de carbono orgânico em horizontes espódicos profundos (Bh), em profundidades que podem variar de 1,5m a 5m. Pesquisas atuais relacionadas ao estoque de carbono em solos amazônicos, não levam em consideração os estoques encontrados no horizonte Bh (abaixo de 1m de profundidade). Sendo assim, o principal objetivo da presente pesquisa foi quantificar e mapear o estoque de carbono nos solos da bacia do Rio Negro, tendo-se em vista aquele estocado no primeiro metro de solo, bem como o carbono armazenado em até 3m de profundidade. A quantidade de carbono orgânico estocado nos solos da bacia do Rio Negro foi estimada em diferentes escalas de mapeamento, desde mapas locais até a escala da bacia do Rio Negro. Imagens de sensoriamento remoto de alta resolução espacial e espectral foram essenciais para viabilizar o mapeamento dos solos nas áreas estudadas e permitir a estimativa do estoque de carbono. Uma análise multisensor foi adotada buscando-se gerar informações biofísicas indiretamente associadas à variação lateral dos tipos de solo. Após o mapeamento do estoque de carbono em escala regional, partiu-se para a estimativa na escala da bacia do Rio Negro, com base em análise geoestatística (krigagem por regressão linear), imagens de sensoriamento remoto e base de dados de domínio público. Após o mapeamento do estoque de carbono na escala da bacia, constatou-se que os Espodossolos têm um estoque médio de 18 kg C m-2, para 1m de profundidade, valor similar ao observado em solos adjacentes (Latossolos e Argissolos) os quais tem um estoque de 15 kg C m-2. Quando são considerados os estoques profundos, até 3m, a quantidade de carbono dos Espodossolos é superior com valores variando de 55 kg C m-2 a 82 kg C m-2. Estoque relativamente maior que aquele observado em solos adjacentes para esta profundidade (18 kg C m-2 a 25 kg C m-2). Portanto, o estoque de carbono profundo dos Espodossolos, não deve ser negligenciado levando-se em conta cenários futuros de mudanças climáticas
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Machač, Michal. "Etika v auditu. Audit a podvod." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-113539.
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This diploma thesis describes ethics in the profession of external and internal audit. It provides comprehensive overview about ethics, from the basic definitions to business ethics. It deals with audit, its history, organisations, Sarbanes -- Oxley Act and ethical relations of audit profession. It is focused on codes of ethics, auditor act and some standards on internal audit related to ethics. Thesis in its theoretical part also speaks about fraud, its basics, frauds in corporations and audit. Practical part of thesis is focused on concrete fraud cases in relation with (un)ethical behaviour of auditors. It is concerned with history and reasons of fall of Arthur Andersen. It shows its unethical behaviour on fraud examples of its clients, american corporations Enron, WorldCom, Sunbeam and Waste Management. This thesis also describes one of the latest fraud in Olympus. Czech republic is represented by the case of Czech office of Deloitte.
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Fuksová, Daniela. "Obchodní podíl v s.r.o." Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-10366.
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The thesis focuses on a member's ownership interest in a limited liability company. In the introduction, we provide an outline of the basic institutes of a limited liability company such as its incorporation and creation, composing of memorandum of association, the way of member's liability etc. Then we define the legal nature of an ownership interest as another property value. The main stress is put particularly on a member's rights and obligations arising from the ownership of his/her interest, and on different changes of members. To illustrate the issues described in the thesis, we also provide relevant judgments rendered by Czech courts in appellate and appellate review proceedings related to ownership interests in limited liability companies.
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Sachr, Jan. "Obchodní podíl v s.r.o." Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-10380.
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The thesis is focused on a member's ownership interest in a limited liability company. First part of the thesis is providing basic information about institutes of limited liability company such as creation and incorporation and statutory body. The main aim of the thesis offers the view on the member's ownership interest in a limited liability company and the possible disposal. At the end are mentioned the contemporary trends relevant to limited liability company.
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Bernardo, Juliana de Oliveira. "Fotopletismografia podal em equinos." Botucatu, 2018. http://hdl.handle.net/11449/180335.
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Orientador: Carlos Alberto HussniResumo: As enfermidades podais do membro torácico são a maior causa das alterações musculoesqueléticas que acometem os equinos. A doença do navicular, osteíte podal e a laminite estão entre as enfermidades de maior incidência em equinos, sendo todas elas citadas como afecções de origem vascular. A fotopletismografia é um método diagnóstico não invasivo que quantifica o tempo de reenchimento venoso baseado na circulação periférica terminal. Objetivou-se estudar a exequibilidade e viabilidade da fotopletismografia podal em equinos, padronizando os valores normais para a espécie. Foram utilizados 10 equinos hígidos, avaliando-se os membros torácicos em diferentes superfícies, sendo dividos em dois grupos: Grupo Borracha (GB) e Grupo Concreto (GC). A fotopletismografia foi realizada com os animais em posição quadrupedal, realizando-se movimentos pendulares para mimetizar movimentos de apoio e elevação do membro, realizando-se cinco movimentos consecutivos e então, imediatamente induzidos ao repouso, obtendo-se então, o tempo de reenchimento venoso (TRV). Não houve diferença significativa entre o membro torácico direito e membro torácico esquerdo nos diferentes grupos (p=0,75). A média do TRV nos equinos do grupo borracha (GB) foi de 12,650 ± 1,694 e no grupo concreto (GC) foi de 12,700 ± 1,387 segundos, não demonstrando diferença significativa entre os diferentes pisos (p=0,98). Os equinos apresentaram valores de referência significativos em relação aos pacientes humanos. Conclui-se que ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The thoracic limb disorders are the major cause of the musculoskeletal changes affecting the horses. Navicular disease, foot osteitis and laminitis are among the diseases of higher incidence in equines, all of which are cited as affections of vascular origin. Photoplethysmography is a noninvasive diagnostic method that quantifies venous refill time based on the terminal peripheral circulation. The objective is study the feasibility of foot photoplethysmography in horses, standardizing the normal values for this species. Thoracic limbs were used on different surfaces and divided into two groups: Rubber Group (RG) and Concrete Group (CG). The photoplethysmography was performed with the animals in a quadrupedal position, with pendular movements being performed to mimic support and elevation movements. Five consecutive movements were performed, and then immediately induced at rest, and venous refilling time (VRT). There was no significant difference between the right and left thoracic limbs in the different groups (p=0.75). The mean TRV in the horses of the rubber group (GB) was 12.650 ± 1.694 and the concrete group (CG) it was 12.700 ± 1.387 seconds, showing no significant difference between the different floors (p=0.98). The reference values in horses are different in relation to human patients. It can be concluded that the photoplethysmography of the thoracic limbs in horses can be used as an auxiliary method to evaluate the microcirculation of the foot, the reference value fo... (Complete abstract click electronic access below)
Doutor
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Bräutigam, Tatjana, Ralf Sinapius, and Holger Joisten. "Steckbrief Podsole aus Dünensand: Böden der Altmoränenlandschaften." Sächsisches Landesamt für Umwelt, Landwirtschaft und Geologie (LfULG), 2017. https://slub.qucosa.de/id/qucosa%3A74408.
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Der Steckbrief informiert über die ˈPodsole aus Dünensandˈ. Die ˈPodsole aus Dünensandˈ zählen zur Bodenklasse der ˈBöden der Altmoränenlandschaftenˈ. Sie stellen eine typische Bodenform in Sachsen dar. Der ˈPodsol aus Dünensandˈ ist ein Boden, der sich in der Altmoränenlandschaft im Gebiet der Sander und Endmoränen auf Flugsandfeldern (Dünen) entwickelt hat. Podsole sind nährstoffarme Böden, die sich durch Verlagerungsprozesse und teilweise Wiederausfällung von Fe, Al, und weiteren Elementen zusammen mit organischen Stoffen auszeichnen und dadurch im oberen Profilteil extrem verarmt sind.
Der Steckbrief richtet sich an alle Interessierte, die sich über die Entstehung Verbreitung und das Erscheinungsbild typischer, repräsentativer Böden Sachsens informieren möchten.
Redaktionsschluss: 01.03.2017
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Nováčková, Barbora. "Plnění rozpočtu v konkrétních podmínkách obce Podolí." Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-5258.
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The theoretic part deals position of municipality, its finance and budget. It briefs of trend in public administration. The theoretic knowledge are shown by means of practical example. The budget of municipality Podolí is subjected to analysis and reviewed throug ratio self-financing and self-support.
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Coufalová, Kateřina. "Hodnocení nastavení systému z podpor mladého zemědělce." Master's thesis, Česká zemědělská univerzita v Praze, 2017. http://www.nusl.cz/ntk/nusl-262967.
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The topic of this thesis is to evaluate the rating system from support of young farmers. The theoretical part of the work draws from the literature, legislative measures and internet resources. The work presents the basic historical data and changes which the Czech Republic has undergone since joining the European Union and the description of the individual institutions are closely linked subsidy policy. There is also a given rules governing young farmers in applying for a grant and definition of their responsibilities arising from the subsequent drawdown approved subsidy. The theoretical part also focuses on the issue of organic farming, which is a European Union increasingly supported and its expansion is included in all programming periods and using grants to less favored areas LFA. They are closely linked to young farmers and farming in these areas is for the applicant advantage at the time of submission.
Custom work is focused on the comparison of two contrasting regions and comparing of interest in agriculture from a gender perspective. Outside the applicants' interest is compared to their success, which is closely related to gender comparison. On the basis of comparison is the conclusion reached in a goal for the proposals and recommendations that can improve the efficiency of subsidies for young farmers and aid and for the future performance of the agricultural sector in the country.
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Jastremská, Kateřina. "Problematika pojistných podvodů na českém pojistném trhu." Master's thesis, Vysoká škola ekonomická v Praze, 2015. http://www.nusl.cz/ntk/nusl-205752.
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The thesis deals with insurance fraud on the Czech insurance market. The introductory section describes the actual state of the insurance market. Insurance fraud is presented in terms of legislation, their species and the general alarming indicators. The next section deals with internal fraud and depictures a brief profile of the typical internal fraudster, indicators of their suspicious behavior and ways of prevention. The following chapter describes the external fraud in the life and non-life insurance, and is supplemented by a separate chapter describing organized fraud. The following part is devoted to statistics of insurance fraud, both from the perspective of the Czech Republic as well as some European countries. The final section describes several fraud detection methods used by insurance companies. Finally, the author proposes certain ways of improving the efficiency of the fight against this crime.
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Achat, David Ludovick. "Biodisponibilite du phosphore dans les sols landais pour les peuplements forestiers de pin maritime." Thesis, Bordeaux 1, 2009. http://www.theses.fr/2009BOR13770/document.
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Afin de garantir une gestion durable du massif forestier des Landes de Gascogne (maintien de la fertilité et production élevée), des études sont nécessaires sur la biodisponibilité du phosphore (P) qui est un facteur limitant. Une évaluation fiable de la biodisponibilité du P passe par la quantification des processus d’acquisition par les plantes, à savoir l’interception racinaire, le transport dans la solution et la mobilisation à l’interface solide-solution d’ions phosphates. Dans ce contexte, l’objectif général de la thèse était de faire un bilan biogéochimique de la biodisponibilité du P dans les sols forestiers des Landes de Gascogne, c'est-à-dire une analyse quantitative et comparative des processus physico- chimiques (diffusion) et biologiques (minéralisation et reminéralisation) de réapprovisionnement de la solution en ions phosphates ainsi qu’une caractérisation du système de prélèvement (racines fines) du Pin maritime. Les résultats ont montré une déficience en P pour l’ensemble des sols étudiés. Ils ont également montré une importance variable, en fonction de la profondeur et du type de lande (humide à sèche), des différents processus biologiques et physico-chimiques dans le réapprovisionnement de la solution. Le rôle des micro-organismes, via la minéralisation du P organique du sol et en tant que source (reminéralisation) et puits (immobilisation) de P, est particulièrement important dans les sols peu réactifs vis-à-vis du P comme les litières ou certains sols minéraux de surface. L’étude du système de prélèvement (racines fines, ectomycorhizes) suggère que le prélèvement de P par le Pin maritime concerne aussi bien les horizons de surface que ceux du sous-solIn order to guarantee a sustainable management of the forest range the “Landes de Gascogne” (maintaining fertility and elevated productivity), the bioavailability of phosphorus (P), a growth limiting factor, needs to be studied. An accurate evaluation of P bioavailability implies the quantification of plant acquisition processes such as root interception, soil solution transport and the mobilisation of phosphate ions at the soil-soil solution interface. The main objective of the PhD study was to assess a biogeochemical balance of the P bioavailability in the forest soils of the “Landes de Gascogne”, i.e. to carry out an quantitative and comparative analysis of the physical-chemical (diffusion) and biological (mineralization and remineralization) processes of replenishing the soil solution with phosphate ions, as well as the characterisation of the tree uptake system (fine roots) of maritime pine. The results have shown that all of the soils studied are very deficient in P. They have further shown a varying importance of the different biological and physical-chemical processes in supplying P to the soil solution according to the site class (humid to dry moorlands). The role of the microorganisms, via the mineralization of organic P, as a source (remineralization) or a sink (immobilization) of P, is particularly important in the litter and top mineral layers featuring a very low reactivity versus P. The study of the uptake system (fine roots and ectomycorrhizae) suggests that uptake of P by maritime pine takes place both in top soil horizons and in deeper soil horizons
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Matušů, Magdalena. "Podíl vinařství na rozvoji okresu Znojmo." Master's thesis, Vysoká škola ekonomická v Praze, 2006. http://www.nusl.cz/ntk/nusl-8152.
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This thesis describe the current situation of winegrowing in the territory of Znojmo, while also describe the evolution and assess the significance of the influence on the development of winemaking district - Znojmo, factors contributing to the regional development of winegrowing, forms of support for this sector, description of the problems in the winegrowing and what are the possibilities for further development of the region in connection with winegrowing. The theoretical part contains only shortly the basic theory of regional development, the thesis continues with a brief description Znojmo district, geographical and economic-social conditions of the territory, then briefly the evolution of winegrowing in the Czech Republic and in detail the evolution of winegrowing in the district of Znojmo. Furthermore author focused on legal aspects of winegrowing in the Czech Republic and the specific conditions of aid after the entry into the EU. Analytical part is focused on the questionnaire survey among inhabitants in the district of Znojmo and the elaboration of SWOT analysis. On the basis of it is then determined the rate of significance for the winegrowing district Znojmo and determined influential factors of development and indicated further opportunities for the development of the region in connection with winegrowing.
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Rajdlová, Dana. "Dostupnost přímých finančních podpor ze strukturálních fondů pro podnikatele." Master's thesis, Vysoká škola ekonomická v Praze, 2007. http://www.nusl.cz/ntk/nusl-848.
Full textAbstract:
Česká republika získala svým vstupem do EU právo čerpat prostředky z jejího rozpočtu rozpočtu k odstraňování regionálních disparit, především v oblasti infrastruktury, ale i rozvoji podnikání, zejména malého a středního. Práce analyzuje dostupnost dvou forem přímých finančních podpor (dotace a zvýhodněný úvěr)ze strukturálních fondů pro malé a střední podnikatele, zejména pak dostupnosti informací o těchto podporách. Jako představitel poskytovatele podpory je uveden podnikatelský subjekt Českomoravská záruční a rozvojová banka, a. s. Jádro práce je soustředěno na zhodnocení administrativní náročnosti přípravy žádosti o podporu v rámci Operačních programů v období 2004 - 2006. Závěrečné shrnutí obsahuje návrhy na opatření ke zlepšení přístupu podnikatelů k podporám, a to zejména v podobě snižování administrativní zátěže žadatelelů o podporu.
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Paneš, Patrik. "Ochrana hospodářské soutěže a úloha poskytování státních podpor podnikům." Doctoral thesis, Vysoká škola ekonomická v Praze, 2004. http://www.nusl.cz/ntk/nusl-77081.
Full textAbstract:
State aid is the government intervention, which affects the economic competition because of the preference of certain market subjects. The European Union has concluded that if there exists any violation of competition in the international scale, it would be the reason for constitution of supranational regulation of its providing. The economic policy of subsidizing of chosen market subjects could be in principle taken into account as the subset of the industrial economic policy. Through it, the governments fulfill their miscellaneous structural intentions, from aborning industries helping till the declining industries saving. However, this type of the economic policy seems to be contrary to the protection of the economic competition, which has been declared as the one of key segments of the economic policy of the European Union. Selective privileges constitute anti-competition policy, so thus has been their control incorporated within the policy of the protection of competition. During the reviewing of the legality of provided state aid, we could see that the authorities prefer simpler, just legal review of the problem instead of the deeper economic testing of the given case. And that is the reason (together with the high recency of the theme), why this dissertation aims the generally neglected, economical aspect of the problem. I.a. it concentrates itself on the sight from the perspective of the Public Choice economic theory, which studies the interrelationship between the worlds of politics and economics. This important relation could not be marginalized and during the research work abstracted. Logical structure of exposed dissertation follows: first ordinary chapter focuses on the theoretical concepts of the state aids. It regards chosen questions from the point of view of different streams of the economic thoughts. It devotes itself especially to the effects of the state aids on the economy from the light of macroeconomics, microeconomics and international economics. It contains also conclusions of some empirical analyses. Next chapter focuses on the legal environment of the branch of subsidizing. Primary it contains communitary regulations of the European Union, secondary the list of legislation relevant for the Czech Republic and within the World Trade Organization, which has constituted unique system of countervailing measures. Next part of the dissertation maps different possibilities of measurement of the extent of granted state aids. With the stipulation of calculation difficulty and resulting lower ability of comparability, it uses subsequently four sources of data. One part of the dissertation is especially devoted to the analytical statistical system of the European Union, which is called the Scoreboard. First, there is characterized its methodology, and further, there is -- with the use of this database -- analyzed the structure of state aid granting within the area of the European Union. Its development is compared with the aim of the Lisbon strategy from the year of 2000. Last ordinary chapter represents the attempt -- on the base of the enterprise data -- to elementary research of the existence of the link between state aid and final market. Analysis could be characterized as the contribution to the -- yet more likely occasionally -- research of the effects of subsidizing within the context of competitiveness of target industry. Tested hypotheses are: larger industries receive more subsidies and industries receiving subsidies do not improve their competitiveness. For the case study has been the combination of four data sources used. The goal of this dissertation is the description of the questions of state aid provision from the highest possible number of different points of view, of course with the accent on the economics and with the stipulation of constraint of (un)availability of relevant data. In the end of the dissertation there are submitted some practical economic policy suggestions. During its elaboration there was wide variety of specialized literature used and great number of relevant thought and data sources processed, after all as the enclosed list at the very end of this thesis could show. The value added of exposed dissertation and its contribution to the existing research of chosen theme is namely the complexity of analysis, the compilation of previously developed knowledge, and also empirical findings.
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Loun, Jakub. "Hodnocení dopadů veřejných podpor na rozvoj podniků v ČR." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-162854.
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Diploma thesis The Impact of Public Subsidies on Development of Enterprises in the Czech Republic examines the real impact on profit, revenues and debts. Counterfactual impact evaluation method is used on companies subsidised from structural funds. These indicators were examined by difference-in-difference method based on the selective research of 1738 companies subsidised from OP Entrepreneurship and Innovation and control group of the same size. The impact of public support on the profit of subsidised companies was quantified as 608 -- 5 547 ths. CZK and the impact on sales as 14 713 -- 42 511 ths. CZK. 1 CZK used for subsidies increased the profit of supported companies by 0.05 -- 0.44 CZK and sales by 1.16 -- 3.35 CZK. Hypothesis that the growth of supported firms increased their debt has not been proved. Also a slight positive effect of support on growth in return on equity was identified.
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Zádamský, Jakub. "Politika hospodářské soutěže ČR v oblasti poskytování veřejných podpor." Master's thesis, Vysoká škola ekonomická v Praze, 2014. http://www.nusl.cz/ntk/nusl-193187.
Full textAbstract:
The efficient competition protection is EU's crucial key objective in order to provide smooth functioning of the local competition and the internal market. Within different segments of the competition I focused on the state aid issue, which is a specific area of the EU competition law. Providing any state aid inevitably influences the market enviroment and carries a considerable risk of the competition distortion. It effects the trade between Member States as well. The main aim of this diploma thesis is not only to describe the European legislation related to state aids, but also its impact on the Czech legal system. The Community state aid rules stem from Articles 107 - 109 of the Treaty on the Functioning of the European Union and their main purpose is to prevent any selective advantages to certain market players. This thesis also focuses on reforms and modernization of the state aid control system, in particular to the State Aid Action Plan.
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Achat, David Ludovick Morel Christian Bakker Mark. "Biodisponibilite du phosphore dans les sols landais pour les peuplements forestiers de pin maritime." S. l. : Bordeaux 1, 2009. http://ori-oai.u-bordeaux1.fr/pdf/2009/ACHAT_DAVID_2009.pdf.
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Martin, Dale Elizabeth. "Chemical properties of root mats in some south coastal British Columbia podzols : implications for classification and genesis." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/26008.
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Podzols, situated at high elevation within the Coast Mountains surrounding Vancouver, often have accumulations of organic material within the mineral soil either as mats above an impermeable layer or as channels running obliquely and horizontally through the B horizon. This organic material is "greasy" to the touch with few discernible mineral grains on hand texturing. The mats range in thickness from 1 cm to greater than 40 cm, are situated in seepage zones and are overlain by a well drained sandy loam, often of low organic content. The channels have the gross morphology of roots and are up to 5 cm wide. Occasional remnants of wood structure are discernable in situ and the cellular nature of the organic material can be seen under the compound microscope.
The majority of the mats could be classified as organic (>17% C), either as an H or an O horizon. If they contained less than 17% C they met the criteria of a Bhf horizon.
Chemically the mats and channels have some unusual properties. They are similar to the surficial humus in carbon to nitrogen ratio and nitrogen to sulphur ratio but much closer to a podzolic B horizon in iron content. The ratio of carbon in humic acids to fulvic acids (Ch/Cf) and polyphenolic to total fulvic acids (Ca/Cf) was also more characteristic of a podzol. The organic mats had an average Ch/Cf of 0.23 and a Ca/Cf of 0.73. This is in comparison with 2.44 and 0.44, respectively, for the surficial humus and 0.34 and 0.72, respectively, in the organic material of the conventionally situated Bhf horizons.
Both mats and channels had very high concentrations of aluminum, sometimes exceeding 10%. From the organic mats on Burke Mountain, aluminum extracted by acid ammonium oxalate was just slightly higher than that extracted with sodium pyrophosphate and oxalate silicon was low. This implied that most of the aluminum was bound with the organic material. In contrast, the oxalate aluminum of Cypress Park mat samples was often more than double that which was extracted with pyrophosphate and oxalate silicon values were also high. The figures indicated that allophane, with an approximate AltSi ratio of 2, may make up a high proportion of this horizon.
Morphologically, the mats and channels seem to have originated through root decomposition but chemically, podzolic mechanisms seem to have played an important role. Because of similarities between soils studied in this thesis and soils of the literature found to contain imogolite, a column study was undertaken to test a mechanism whereby decomposing roots could be enriched by the aluminum of proto-imogolite. It was found that the organic material of rotting wood could scavenge aluminum from this positively charged aluminosilicate colloid and that in the process the fulvic acids of the wood were also immobilized. If a mechanism similar to this was operating within a podzol, it could help explain both the high concentration of aluminum and of fulvic acids in the mats and channels.Land and Food Systems, Faculty of
Graduate
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Gillot, Florence. "Genèse et évolution des smectites de transformation de trois chronoséquences (300-10000 ans) de podzols de Finlande." Poitiers, 1999. http://www.theses.fr/1999POIT2300.
Full textAbstract:
La formation pedogenetique des mineraux argileux a ete etudiee dans trois chronosequences de podzol de finlande (300 a 10000 ans). La premiere sequence est developpee sur des sables fluvio-glaciaires de finlande nord (150-4450 ans hors gel). La seconde sequence est developpee sur des moraines (tills) de laponie (2800-4500 ans hors gel). La troisieme sequence est developpee sur des tills en finlande centrale (2900 ans-5400 ans hors gel). Les mineraux argileux ont ete etudies par diffraction des rayons x, microscopie electronique a transmission et microscopie analytique. Les transformations pedogeniques observees etaient les memes pour les trois chronosequences. Des smectites dioctaedriques (beidellites) sont formees dans les horizons e eluviaux des podzols apres 3600 ans hors gel, lorsqu'ils sont developpes sur des tills, alors que 600 ans hors gel seulement sont necessaires pour produire des smectites dans les sols developpes sur sables fluvio-glaciaires. Pour tous les podzols, la charge interfoliaire des feuillets des smectites diminue avec la duree d'evolution des sols, des smectites de basse-charge sont observees apres 5300 ans hors gel. Une analyse detaillee par microscopie electronique analytique permet de distinguer deux populations principales dans les horizons eluviaux. Ces smectites sont toutes de type beidellite, mais la premiere population est constituee de particules de faible extension laterale et comprennant un nombre reduit de feuillets par cristal, elles contiennent du fer et du magnesium. La seconde population, plus strictement alumineuse, est composee de particules d'extension laterale plus grande et ayant un plus grand nombre de feuillets par cristal. Les smectites derivent de la transformation des chlorites et des micas ferro-magnesiens pour la premiere population, et, de la transformation des micas dioctaedriques (phengite, muscovite) pour la seconde. Le premier processus (le plus precoce et le plus rapide) contribue de facon preponderante a la formation des smectites, tant que les reserves en phyllosilicates ferromagnesiens ne sont pas epuisees. En consequence, les smectites des horizons e des podzols sont un melange dont les proportions et les caracteristiques de ses composants changent au cours du temps.