278 resultados para Physiographic compartmentalization


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This paper presents a method applied to the seacoast town of Peruibe, São Paulo State, Brazil. The method encompasses the application of remote sensing interpretation techniques and field survey to obtain geotechnical data and thus generate cartographic products composed of easily grouped units that work as database objects and can de used to assist geotechnical zoning. The so-called Compartmentalization Basic Units (CBUs) show the smallest land surface analyzed from its physiographic elements and have in their cores the same geotechnical properties, making it easier to analyze the potentialities and the fragilities of the physical environment and its susceptibility to the action of natural and anthropic processes. In the study area, sixty-eight units were individualized in which geotechnical properties were inferred by photo interpretation criteria, using textural properties of the image adjusted with field observations. The method proved to be easily reproducible, and is especially useful in regions where the absence of basic maps makes it impossible to establish homogeneous zones through traditional overlay of different topic informations.

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The erosion is a natural process of detachment, transport and deposition of soil and rock particles from one place to another. Human activities with no previous planning may accelerate this process, causing several damages to the environment and to society. In order to control the acceleration of these erosion processes caused by humans, prevention and improvement initiatives emerge. Regarding works which interfere directly in some of the natural resources, these initiatives must respect the intrinsic physical properties of the area of interest, if they aim to obtain effective results. Based on this scenario, this work proposes a few methods of accelerated linear erosion prevention, control and recovery in a specific area of the municipal district of Ipeúna (SP). For that matter, this study is based on a method of physiographic compartmentalization of the area, considering and integrating soil, relief, geology and the use and land cover properties of the study area. Plus, a flowchart with general orientations regarding management of eroded areas was produced, focused on the control and recovery of linear erosion. The result demonstrates the importance of careful erosion control, respecting the physical properties of each physiographic unit. The vegetative and mechanical conservationists methods, and the discipline of water flow, have found wide applicability in the study area.

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Geological-geotechnical problems affecting escarps as well as embankment and fill slopes of roads and motorways may generate different types of unsteadiness, which are mainly arisen from the deficient knowledge about the physical environment. This results in unsuitable engineering projects and inadequate executions, which can be worsened by an occasional inappropriate maintenance of the construction. A geologically-geotechnically characterization of escarps and slopes is crucial in order to prevent these problems. This work deals with a geological-geotechnical study of 1:10.000 scale mapping in a stretch of a local road (CHQ-40) at the Serra de Itaqueri, Charqueada town, State of São Paulo. The stretch is known by several physical problems as erosion and mass movement. The methods of study were based on an integrative analysis of the diverse elements of the physical environment by using aerial photographs - to obtain the physiographic compartmentalization of terrain units - as well as field work - to accomplish the evaluation of the units by employing sketch lists. To achieve this, we selected several techniques in order to identify and classify different types of existing problems as erosion, landslide in embankments and fill slopes, rockfall, block rolling, among others. We also included the analysis of soil horizon, thickness and composition. The geological-geotechnical mapping resulted in six units: 1- Sandstones in cuesta’s backhill; 2 – Basalts in cuesta’s front; 3- Sandstones in cuesta’s front; 4 – Talus and colluvial deposits at cuesta’s foothill; 5- Sandstones of the Piramboia Formation in hillside; and 6 – Colluvial soil in the hill top. A characterization of the geological-geotechnical units is detailed, coupled to the cartographic material. Other cartographic products elaborated for this study included 1:10.000 maps of hypsometry, slope and curvature

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The technique of micellar compartmentalization has been used to inhibit the diffusion-controlled self-quenching process in thioketones. By adjusting the ratio of the bulk concentration of the thioketone solute to the bulk concentration of micelles multiple occupancy of the micelles was avoided. Under these conditions enhanced phosphorescence intensity was observed in nitrogen-purged micellar solutions compared with that in acetonitrile solutions, indicating that the thioketone triple was indeed protected from deactivation by a ground statet

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Functional MRI (fMRI) can detect blood oxygenation level dependent (BOLD) hemodynamic responses secondary to neuronal activity. The most commonly used method for detecting fMRI signals is the gradient-echo echo-planar imaging (EPI) technique because of its sensitivity and speed. However, it is generally believed that a significant portion of these signals arises from large veins, with additional contribution from the capillaries and parenchyma. Early experiments using diffusion-weighted gradient-echo EPI have suggested that intra-voxel incoherent motion (IVIM) weighting inherent in the sequence can selectively attenuate contributions from different vessels based on the differences in the mobility of the blood within them. In the present study, we used similar approach to characterize the apparent diffusion coefficient (ADC) distribution within the activated areas of BOLD contrast. It is shown that the voxel values of the ADCs obtained from this technique can infer various vascular contributions to the BOLD signal.

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Alasdair MacIntyre condemns modern politics, specifically liberalism and the institutions of the liberal state, as irredeemably fallen. His core argument is that the liberal state encourages a disempowering ‘compartmentalization’ of people’s everyday roles and activities that undermines the intersubjective conditions of human flourishing. MacIntyre’s alternative is an Aristotelian politics centred on the notion of “practice.” Defined by justice and solidarity, this politics can only be realized, he claims, within local communities which oppose and resist the dictates of the administrative state and capitalist market. Here it is argued that MacIntyre’s notion of “practice” represents a compelling ethical-political ideal. However, the belief that this ideal is best realized within local communities is rejected. In privileging local community, MacIntyre relies on a reductive view of modern states and overlooks the institutional conditions of a just polity. Against this, it is argued that a politics of human flourishing cannot succeed without an emancipatory transformation of large-scale, trans-communal institutions, in particular the state.

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In den letzten Jahrzehnten haben sich makroskalige hydrologische Modelle als wichtige Werkzeuge etabliert um den Zustand der globalen erneuerbaren Süßwasserressourcen flächendeckend bewerten können. Sie werden heutzutage eingesetzt um eine große Bandbreite wissenschaftlicher Fragestellungen zu beantworten, insbesondere hinsichtlich der Auswirkungen anthropogener Einflüsse auf das natürliche Abflussregime oder der Auswirkungen des globalen Wandels und Klimawandels auf die Ressource Wasser. Diese Auswirkungen lassen sich durch verschiedenste wasserbezogene Kenngrößen abschätzen, wie z.B. erneuerbare (Grund-)Wasserressourcen, Hochwasserrisiko, Dürren, Wasserstress und Wasserknappheit. Die Weiterentwicklung makroskaliger hydrologischer Modelle wurde insbesondere durch stetig steigende Rechenkapazitäten begünstigt, aber auch durch die zunehmende Verfügbarkeit von Fernerkundungsdaten und abgeleiteten Datenprodukten, die genutzt werden können, um die Modelle anzutreiben und zu verbessern. Wie alle makro- bis globalskaligen Modellierungsansätze unterliegen makroskalige hydrologische Simulationen erheblichen Unsicherheiten, die (i) auf räumliche Eingabedatensätze, wie z.B. meteorologische Größen oder Landoberflächenparameter, und (ii) im Besonderen auf die (oftmals) vereinfachte Abbildung physikalischer Prozesse im Modell zurückzuführen sind. Angesichts dieser Unsicherheiten ist es unabdingbar, die tatsächliche Anwendbarkeit und Prognosefähigkeit der Modelle unter diversen klimatischen und physiographischen Bedingungen zu überprüfen. Bisher wurden die meisten Evaluierungsstudien jedoch lediglich in wenigen, großen Flusseinzugsgebieten durchgeführt oder fokussierten auf kontinentalen Wasserflüssen. Dies steht im Kontrast zu vielen Anwendungsstudien, deren Analysen und Aussagen auf simulierten Zustandsgrößen und Flüssen in deutlich feinerer räumlicher Auflösung (Gridzelle) basieren. Den Kern der Dissertation bildet eine umfangreiche Evaluierung der generellen Anwendbarkeit des globalen hydrologischen Modells WaterGAP3 für die Simulation von monatlichen Abflussregimen und Niedrig- und Hochwasserabflüssen auf Basis von mehr als 2400 Durchflussmessreihen für den Zeitraum 1958-2010. Die betrachteten Flusseinzugsgebiete repräsentieren ein breites Spektrum klimatischer und physiographischer Bedingungen, die Einzugsgebietsgröße reicht von 3000 bis zu mehreren Millionen Quadratkilometern. Die Modellevaluierung hat dabei zwei Zielsetzungen: Erstens soll die erzielte Modellgüte als Bezugswert dienen gegen den jegliche weiteren Modellverbesserungen verglichen werden können. Zweitens soll eine Methode zur diagnostischen Modellevaluierung entwickelt und getestet werden, die eindeutige Ansatzpunkte zur Modellverbesserung aufzeigen soll, falls die Modellgüte unzureichend ist. Hierzu werden komplementäre Modellgütemaße mit neun Gebietsparametern verknüpft, welche die klimatischen und physiographischen Bedingungen sowie den Grad anthropogener Beeinflussung in den einzelnen Einzugsgebieten quantifizieren. WaterGAP3 erzielt eine mittlere bis hohe Modellgüte für die Simulation von sowohl monatlichen Abflussregimen als auch Niedrig- und Hochwasserabflüssen, jedoch sind für alle betrachteten Modellgütemaße deutliche räumliche Muster erkennbar. Von den neun betrachteten Gebietseigenschaften weisen insbesondere der Ariditätsgrad und die mittlere Gebietsneigung einen starken Einfluss auf die Modellgüte auf. Das Modell tendiert zur Überschätzung des jährlichen Abflussvolumens mit steigender Aridität. Dieses Verhalten ist charakteristisch für makroskalige hydrologische Modelle und ist auf die unzureichende Abbildung von Prozessen der Abflussbildung und –konzentration in wasserlimitierten Gebieten zurückzuführen. In steilen Einzugsgebieten wird eine geringe Modellgüte hinsichtlich der Abbildung von monatlicher Abflussvariabilität und zeitlicher Dynamik festgestellt, die sich auch in der Güte der Niedrig- und Hochwassersimulation widerspiegelt. Diese Beobachtung weist auf notwendige Modellverbesserungen in Bezug auf (i) die Aufteilung des Gesamtabflusses in schnelle und verzögerte Abflusskomponente und (ii) die Berechnung der Fließgeschwindigkeit im Gerinne hin. Die im Rahmen der Dissertation entwickelte Methode zur diagnostischen Modellevaluierung durch Verknüpfung von komplementären Modellgütemaßen und Einzugsgebietseigenschaften wurde exemplarisch am Beispiel des WaterGAP3 Modells erprobt. Die Methode hat sich als effizientes Werkzeug erwiesen, um räumliche Muster in der Modellgüte zu erklären und Defizite in der Modellstruktur zu identifizieren. Die entwickelte Methode ist generell für jedes hydrologische Modell anwendbar. Sie ist jedoch insbesondere für makroskalige Modelle und multi-basin Studien relevant, da sie das Fehlen von feldspezifischen Kenntnissen und gezielten Messkampagnen, auf die üblicherweise in der Einzugsgebietsmodellierung zurückgegriffen wird, teilweise ausgleichen kann.

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Spatial and temporal patterns in the distribution of the zooplankton in a large tropical reservoir were investigated for a year. The zooplankton was sampled at 10 limnetic stations. Rotifera were richest in number of species and individuals, especially in transitional river-lake zones. They were dominant during the summer in nine sampling stations, and decreased in spring. The main species were Polyarthra vulgaris, Keratella americana, K. cochlearis and Conochilus unicornis. Polyarthra vulgaris was widely distributed. Keratella was more abundant at upstream stations, and a dense population of C. unicornis was observed in a lateral, sheltered compartment. Among copepods, Calanoida were more abundant in spring and Cyclopoida in autumn. Longitudinal gradients in the Calanoida/Cyclopoida relation were observed, with the predominance of Cyclopoida at upstream sampling stations and Calanoida in more lacustrine zones towards the dam. Notodiaptomus iheringi, Thermocyclops minutus and T. decipiens were the main species. Diaphanosoma birgei, the most abundant cladoceran, mainly occurred in lacustrine zones, while Moina minuta was more abundant at riverine sampling stations, generally in association with Bosminopsis deitersi. Peaks of tintinnid protozoans were observed in upstream zones during summer and spring.

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Patterns in the spatial and temporal composition, dominance and abundance of the phytoplankton community of the Jurumirim Reservoir (Brazil) were studied during one year at ten different sampling stations. The main phytoplankton associations were characterized by diatoms and blue-green algae, in distinctive patterns of dominance. The main species were Microcystis aeruginosa Kuetz, Anabaena circinalis Rabenhorst, A. spiroides Kleb., A. solitaria Kleb., Aulacoseira cf. italica Grunow and A. granulata (Ehr.) Simon. A high growth of Aulacoseira was observed in the upstream zones of the reservoir in spring, at the beginning of the seasonal rainy period. This growth was a response to increased flow rates and input of fresh nutrients by the main feeder rivers. A high concentration of blue-green algae, especially Anabaena circinalis and A. spiroides, was observed in winter (dry season) in the lacustrine part of the reservoir, towards the dam. These algae benefitted from the longer water retention times and greater internal circulation of nutrients in the absence of a thermocline at this time of the year. Among the Cyanophyceae, there was an alternation between M. aeruginosa, more abundant in summer, and Anabaena, dominant in autumn and winter. A conspicuous growth of Anabaena occurred in a diverticle of the reservoir, sheltered from the main advective processes that predominate in the central channel. Higher phytoplankton diversity was associated with the contact zone between riverine and lacustrine systems.