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Health and climate: relations between dengue and atmospheric elements in the metropolitan region of Fortaleza / Clima e saÃde: relaÃÃes entre os elementos atmosfÃricos e a dengue na regiÃo metropolitana de FortalezaGledson Bezerra MagalhÃes 27 June 2011 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / The aim of this work consists at analyzing the manifestation of âdengueâ at Metropolitan Region of Fortaleza between the years 2001 to 2009, relating the number of cases and incidences of the disease with the infestation of its principal vector and the climatic characteristics of the region. So, were purchased rainfall data, air temperature, the larval infestation of the mosquito Aedes aegypti, the number of cases and incidence of dengue. It was crafted maps, charts and statistical correlations that were established between the variables. It was verified a behavior of spatially and temporally heterogeneous rains, but it was similar each year. Over the years with large amounts of rain and homogeneity of precipitation in the rainy court, the highest number of cases of dengue occurred one to two months after the large rainfall totals, which is not the case in years with low rainfall where the greatest amount of Dengue cases occurred both in the month with the highest total rainfall as in other months they had succeeded or within 2 months the rainfall peaks. In years when there were few cases of dengue, there was a spatial and temporal randomness of their cases, and apparently lower connection with the atmospheric elements. In epidemic years, there is a clearer monthly relationship between number of cases and precipitation as well as a greater temporal similarity in the behavior of dengue among the municipalities. It was not identified relationships between the monthly temperature variations with cases of dengue and Aedes aegypti infestation, however it was noted that minimum, mean and maximum temperatures favor the spread of disease. In despite of the correlations between air temperature and dengue cases show negative results, it can not be said that the lower temperatures favor the increase of dengue cases more than maximum temperatures, due to the fact that other factors, such as precipitation, have a greater influence on the spread of the disease. / O objetivo desse trabalho constituiu-se em analisar manifestaÃÃo da dengue na RegiÃo Metropolitana de Fortaleza entre os anos 2001 a 2009, relacionando a quantidade de casos e as incidÃncias da doenÃa com a infestaÃÃo predial de seu principal vetor e com as caracterÃsticas climÃticas da regiÃo. Para isso, foram adquiridos dados de precipitaÃÃo, temperatura do ar, infestaÃÃo da larva do mosquito Aedes aegypti, nÃmero de casos e incidÃncia de dengue. Confeccionaram-se mapas, grÃficos e estabeleceram-se correlaÃÃes estatÃsticas entre as variÃveis. Verificou-se um comportamento de chuvas heterogÃneo espacial e temporalmente, porÃm similar a cada ano. Nos anos de grandes quantidades de chuva e homogeneidade espacial da precipitaÃÃo na quadra chuvosa, a maior quantidade de casos de dengue ocorreu entre um a dois meses depois dos grandes totais pluviomÃtricos, o que nÃo se verifica em anos com poucas precipitaÃÃes onde a maior quantidade de casos de dengue ocorreu tanto no mÃs com maior total pluviomÃtrico como em outros meses que tiveram precipitaÃÃo ou que sucedeu em atà 2 meses os picos de chuva. Nos anos em que ocorreram poucos casos de dengue, observou-se uma aleatoriedade espaÃo-temporal de seus casos, e aparentemente uma menor relaÃÃo com os elementos atmosfÃricos. Jà em anos de epidemia, nota-se uma relaÃÃo mensal mais nÃtida entre nÃmero de casos e precipitaÃÃo, assim como uma maior similaridade temporal no comportamento da dengue entre os municÃpios. NÃo se identificou relaÃÃes entre as amplitudes tÃrmicas mensais com os casos de dengue e de infestaÃÃo do Aedes aegypti, todavia notou-se que as temperaturas mÃnimas, mÃdias e mÃximas sÃo favorÃveis a propagaÃÃo da doenÃa. Apesar das correlaÃÃes entre a temperatura do ar e os casos de dengue apresentarem resultados negativos, nÃo se pÃde afirmar que as menores temperaturas favorecem o aumento de casos de dengue mais do que as temperaturas mÃximas, devido ao fato de outros fatores, como a precipitaÃÃo, terem uma influÃncia maior na propagaÃÃo da doenÃa.
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Estudo da ocorrência de superfícies de aplanamento em transectos no setor oriental do Estado do ParanaStefanello, Ana Clarissa 07 May 2012 (has links)
Resumo: Nesta tese se estuda a distribuição das superfícies de aplanamento relacionadas à morfogênese paleoclimática, em transectos no setor oriental do Estado do Paraná. A área de estudo é delimitada por um transecto que compreende a porção centro-norte da Planície Litorânea, seguindo em direção a Serra do Mar, ao Primeiro Planalto, na região da Superfície de Curitiba e do extremo meridional da bacia do Ribeira, mais especificamente, abrangendo parte da bacia do Capivari e da região montanhosa do Açungui, ao norte referido planalto. Este transecto chega ao leste do Segundo Planalto envolvendo, em seu setor norte, parte da Superfície do Purunã e da bacia do Alto Tibagi e no setor sul, parte da bacia do Médio Iguaçu. Classificações exploratórias para esta porção do relevo do território paranaense foram elaboradas com base em características fisiográficas e morfoclimáticas, ou seja, foram consideradas as superfícies de aplanamento de morfogênese climática. Deste modo, como objetivo principal, buscou-se o registro da ocorrência de tais superfícies, com o uso de um modelo digital de elevação do terreno, cujos dados são gerados por imagens de radar disponibilizadas pelo projeto Shuttle Radar Topografic Mission. Como metodologia de pesquisa, considerou-se o modelo conceitual de origem e evolução das superfícies aplanadas, desenvolvido com base na influência das alternâncias climáticas cenozóicas, entre fases semiáridas e úmidas, no relevo. Essas superfícies são classificadas na literatura segundo critérios que abrangem a hipsometria, a litologia e a cronologia de tais geoformas. São de interesse particular nesta tese, dentre as superfícies de erosão, as grandes superfícies aplanadas situadas acima dos níveis de pedimentação – os pediplanos – denominadas Pd3, Pd2 e Pd1. Os dados obtidos foram organizados e sintetizados, estabelecendo-se um gradiente altimétrico para cada pediplano. Foi realizado um mapeamento exploratório no transecto, obtendo-se o registro da ocorrência das superfícies aplanadas em seus diversos níveis, ou seja, tanto dos níveis de erosão, quanto dos níveis de sedimentação. Esse mapeamento, associado à proposição de critérios específicos para compartimentação, possibilitou constatar a distribuição de superfícies relacionadas à pediplanos na área objeto de estudo. A ocorrência significativa dessas superfícies de aplanamento no relevo sugere a possibilidade de uma reclassificação geomorfológica para o território do Estado do Paraná, complementando-se a subdivisão clássica realizada por Reinhard Maack na década de 1940.
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Speleogenesis and secondary cave minerals in quartz-sandstone and quartzite environment / Speleogenesi e minerali secondari in ambiente quarzitico e quarzo-areniticoSauro, Francesco <1984> 07 April 2014 (has links)
The main objective of this research is to improve the comprehension of the processes controlling the formation of caves and karst-like morphologies in quartz-rich lithologies (more than 90% quartz), like quartz-sandstones and metamorphic quartzites. In the scientific community the processes actually most retained to be responsible of these formations are explained in the “Arenisation Theory”. This implies a slow but pervasive dissolution of the quartz grain/mineral boundaries increasing the general porosity until the rock becomes incohesive and can be easily eroded by running waters. The loose sands produced by the weathering processes are then evacuated to the surface through processes of piping due to the infiltration of waters from the fracture network or the bedding planes.
To deal with these problems we adopted a multidisciplinary approach through the exploration and the study of several cave systems in different tepuis. The first step was to build a theoretical model of the arenisation process, considering the most recent knowledge about the dissolution kinetics of quartz, the intergranular/grain boundaries diffusion processes, the primary diffusion porosity, in the simplified conditions of an open fracture crossed by a continuous flow of undersatured water. The results of the model were then compared with the world’s widest dataset (more than 150 analyses) of water geochemistry collected till now on the tepui, in superficial and cave settings.
All these studies allowed verifying the importance and the effectiveness of the arenisation process that is confirmed to be the main process responsible of the primary formation of these caves and of the karst-like superficial morphologies. The numerical modelling and the field observations allowed evaluating a possible age of the cave systems around 20-30 million of years.
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Tectonic geomorphology and active strain of the Northern Apennines mountain frontPonza, Alessio <1975> 09 April 2010 (has links)
The Northern Apennines (NA) chain is the expression of the active plate margin between Europe and Adria. Given the low convergence rates and the moderate seismic activity, ambiguities still occur in defining a seismotectonic framework and many different scenarios have been proposed for the mountain front evolution. Differently from older models that indicate the mountain front as an active thrust at the surface, a recently proposed scenario describes the latter as the frontal limb of a long-wavelength fold (> 150 km) formed by a thrust fault tipped around 17 km at depth, and considered as the active subduction boundary. East of Bologna, this frontal limb is remarkably very straight and its surface is riddled with small, but pervasive high- angle normal faults. However, west of Bologna, some recesses are visible along strike of the mountain front: these perturbations seem due to the presence of shorter wavelength (15 to 25 km along strike) structures showing both NE and NW-vergence. The Pleistocene activity of these structures was already suggested, but not quantitative reconstructions are available in literature.
This research investigates the tectonic geomorphology of the NA mountain front with the specific aim to quantify active deformations and infer possible deep causes of both short- and long-wavelength structures.
This study documents the presence of a network of active extensional faults, in the foothills south and east of Bologna. For these structures, the strain rate has been measured to find a constant throw-to-length relationship and the slip rates have been compared with measured rates of erosion.
Fluvial geomorphology and quantitative analysis of the topography document in detail the active tectonics of two growing domal structures (Castelvetro - Vignola foothills and the Ghiardo plateau) embedded in the mountain front west of Bologna. Here, tilting and river incision rates (interpreted as that long-term uplift rates) have been measured respectively at the mountain front and in the Enza and Panaro valleys, using a well defined stratigraphy of Pleistocene to Holocene river terraces and alluvial fan deposits as growth strata, and seismic reflection profiles relationships. The geometry and uplift rates of the anticlines constrain a simple trishear fault propagation folding model that inverts for blind thrust ramp depth, dip, and slip.
Topographic swath profiles and the steepness index of river longitudinal profiles that traverse the anti- clines are consistent with stratigraphy, structures, aquifer geometry, and seismic reflection profiles.
Available focal mechanisms of earthquakes with magnitude between Mw 4.1 to 5.4, obtained from a dataset of the instrumental seismicity for the last 30 years, evidence a clear vertical separation at around 15 km between shallow extensional and deeper compressional hypocenters along the mountain front and
adjacent foothills. In summary, the studied anticlines appear to grow at rates slower than the growing rate of the longer-
wavelength structure that defines the mountain front of the NA. The domal structures show evidences of NW-verging deformation and reactivations of older (late Neogene) thrusts.
The reconstructed river incision rates together with rates coming from several other rivers along a 250 km wide stretch of the NA mountain front and recently available in the literature, all indicate a general increase from Middle to Late Pleistocene. This suggests focusing of deformation along a deep structure, as confirmed by the deep compressional seismicity. The maximum rate is however not constant along the mountain front, but varies from 0.2 mm/yr in the west to more than 2.2 mm/yr in the eastern sector, suggesting a similar (eastward-increasing) trend of the apenninic subduction.
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Analisi critica di modelli previsionali per le frane in Emilia Romagna / Analysis of forecasting models for landslides in Emilia RomagnaFranceschini, Silvia <1982> 11 May 2012 (has links)
Questa tesi di dottorato è inserita nell’ambito della convenzione tra ARPA_SIMC (che è l’Ente finanziatore), l’Agenzia Regionale di Protezione Civile ed il Dipartimento di Scienze della Terra e Geologico - Ambientali dell’Ateneo di Bologna.
L’obiettivo principale è la determinazione di possibili soglie pluviometriche di innesco per i fenomeni franosi in Emilia Romagna che possano essere utilizzate come strumento di supporto previsionale in sala operativa di Protezione Civile. In un contesto geologico così complesso, un approccio empirico tradizionale non è sufficiente per discriminare in modo univoco tra eventi meteo innescanti e non, ed in generale la distribuzione dei dati appare troppo dispersa per poter tracciare una soglia statisticamente significativa. È stato quindi deciso di applicare il rigoroso approccio statistico Bayesiano, innovativo poiché calcola la probabilità di frana dato un certo evento di pioggia (P(A|B)) , considerando non solo le precipitazioni innescanti frane (quindi la probabilità condizionata di avere un certo evento di precipitazione data l’occorrenza di frana, P(B|A)), ma anche le precipitazioni non innescanti (quindi la probabilità a priori di un evento di pioggia, P(A)).
L’approccio Bayesiano è stato applicato all’intervallo temporale compreso tra il 1939 ed il 2009.
Le isolinee di probabilità ottenute minimizzano i falsi allarmi e sono facilmente implementabili in un sistema di allertamento regionale, ma possono presentare limiti previsionali per fenomeni non rappresentati nel dataset storico o che avvengono in condizioni anomale. Ne sono esempio le frane superficiali con evoluzione in debris flows, estremamente rare negli ultimi 70 anni, ma con frequenza recentemente in aumento. Si è cercato di affrontare questo problema testando la variabilità previsionale di alcuni modelli fisicamente basati appositamente sviluppati a questo scopo, tra cui X – SLIP (Montrasio et al., 1998), SHALSTAB (SHALlow STABility model, Montgomery & Dietrich, 1994), Iverson (2000), TRIGRS 1.0 (Baum et al., 2002), TRIGRS 2.0 (Baum et al., 2008). / This PhD thesis is inserted in the agreement between ARPA_SIMC (which is the sponsor), the Regional Civil Protection and the Department of Earth Sciences and Geo - Environmental of the University of Bologna.
The main objective is the determination of possible rainfall thresholds for triggering landslides in Emilia Romagna, which can be used as an aid in forecasting operations of Civil Protection.
In a such complex geological context, the distinction between critical and non-critical rainfall is not trivial: when different outputs (failure or no-failure) can be obtained for the same input (a given rainfall event) a deterministic approach is no longer applicable and a probabilistic model is needed. We use a Bayesian statistical approach, applied to a dataset ranging between 1939 and 2009, that is a direct application of conditional probabilities. The conditional probability is the probability of some event A (in our case a landslide) given the occurrence of some other event B (a rainfall episode with a certain magnitude, expressed in terms of total rainfall, intensity or any other variable). Conditional probability is written P(A|B) and it is read “the probability to have a landslide (A) given a rainfall episode (B)”.
Probabilistic Bayesian thresholds minimize false alarms and can be easily implemented in a regional warning system, but their predictive capacity is limited about phenomena that are not represented in the historical dataset. This is the case of shallow landslides evolving in debris flows, extremely rare in the last 70 years, but, recently, their frequency is increasing.
We tried to address this problem by testing the predictive capacity of some physically based models developed in literature, as X - SLIP (Montrasio et al., 1998), SHALSTAB (model Shallow Stability, Montgomery & Dietrich, 1994), Iverson (2000), TRIGRS 1.0 (Baum et al., 2002), TRIGRS 2.0 (Baum et al., 2008).
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Tracing bedload transport in Alpine mountain streams by means of PIT-tagged particles: interplay between sediment supply and hydro-meteorological forcingToro, Matteo January 2016 (has links)
Conceptual models of first-order controls governing river channel dynamics in mountain streams have been rarely tested in the field. In this Ph.D. thesis we examine the effects of hydro-meteorological forcing and sediment supply on the bedload transport dynamics of mountain streams. To this purpose we select three step-pool mountain streams that share identical granitic lithology, but exhibit contrasting sediment supply and hydro-climatic conditions. The three study sites, which are located in Trentino, Eastern Italian Alps, include the Ussaia Creek (2.3 km2) in Val di Sole, and the Grigno and Tolvà Creeks (7 km2) in Valsugana. The former is characterized by high, sand-rich sediment supply delivered by some 20 m-thick glacigenic deposits. The latter two, which flow through glacially carved bedrock terrain, are disconnected from colluvial sediment inputs so that sediment sources are limited to channel banks and bars during high flows. Mean annual precipitation is respectively 844 mm in Ussaia Creek and 1511 mm in Grigno and Tolvà Creeks. All study streams experience, to variable extents, snowmelt and rainfall-induced bedload transporting flows. To estimate quantitatively the effects and the interactions associated with sediment supply and hydro-meteorological forcing, we monitor precipitation and atmospheric temperature. Hydrological levels at instrumented sections are recorded via pressure transducers. Bedload transport is monitored by tagging and tracking 632 stones (b-axis: 30 to 131 mm; weight 88-4004 g). The tracking of these PIT-tagged tracers was conducted from December 2013 to December 2015 by means of an RFID portable pole antenna. Cumulatively, a total of 16, 11 and 19 bedload events were monitored respectively at Grigno, Tolvà and Ussaia Creek. We measured displacement lengths occurred during inter-survey periods, induced by peak flows associated to snowmelt, rainfall or a combination of the two (mixed-type). Active channel depth was evaluated via direct digging tests at the three study sites finding a median burial depth of 0.1 m at Grigno and Tolvà Creeks, and 0.25 m at Ussaia Creek; recent findings (Schneider et al., 2014), show that ordinary bedload events of boulder-bed streams in the Alps, active layer thickness is comprised within 0.01 and 0.22 m; Houbrechts et al. (2012) demonstrated that in mountain streams the active layer thickness is lower than D50. The active layer width was evaluated via orthophoto maps obtained through Structure-from-Motion. To characterize the streambed roughness and the channel slope we conducted topographic and morphologic surveys. To evaluate event-based bedload sediment volumes we applied the virtual velocity approach (Haschenburger and Church, 1998). In particular, to assess the minimum discharge able to entrain clasts, determining the virtual transport duration of each tracer weight class, we used the competence flow method. In order to evaluate the uncertainty associated with methodology that has been customarily applied in the literature, we performed a sensitivity analysis of the evaluation of bedload transfer proposing three scenarios varying the assumptions that (i) virtual velocities are normally distributed and therefore justifying the adoption of median virtual velocities instead of the average virtual velocity, (ii) that active channel width is constant in time, hence replacing bankfull width with site-specific active widths, evaluated on the base of PIT-tagged particles displacements. The monitoring year 2014 was characterized by a total annual precipitation two times larger than the historical mean, associated to a prolonged snowmelt and to heavy storm front events. By contrast, in 2015 we observed no snowmelt and no precipitation occurred in November and December. At Grigno and Tolvà Creeks, the majority of sediment is transported during autumn storm fronts (median travel distance: 30 m) and secondarily by summer convective storms (median travel distance: 4.5 m). At Ussaia Creek, snowmelt-related events induced 17% of the observed displacement lengths (median travel distance: 2 m), but the primary source of sediment transport is associated chiefly with prolonged storm fronts (median travel distance: 200 m). The mass of tracers does not affect virtual velocities, that are instead affected by seasonal distribution of hydro-meteorological events. In fact, at Grigno and Tolvà Creeks we observe a stratification of velocities according to hydro-meteorological forcing, with the largest values observed during rainfall season, commonly associated to highest values of peak discharge. Variability of virtual velocities at Ussaia Creek does not depend on seasonal hydro-climatic forcing and peak discharge values, with distributions of virtual velocities partly overlapping among snowmelt- and rainfall-related events. The seasonal pattern is translated to bedload transport volumes, with Ussaia Creek transporting by the end of the snowmelt period in 2014, three times more sediment than Grigno Creek. This is testified by a prolonged autumn rainfall that hit simultaneously the study sites, caused a debris-flow that transported 1084 m3 at Ussaia Creek, a much larger quantity compared to the 32.2 m3 evaluated at Grigno and the 62.5 m3 at Tolvà Creek. The definition of rainfall intensity-duration thresholds of precipitation events triggering bedload at our sites shows that transport-limited systems (i.e., Ussaia Creek) result sensitive to precipitation inputs characterized by low rainfall intensity (below 5 mm hr-1) and large duration. Conversely, supply-limited systems (i.e., Grigno and Tolvà Creeks) exhibit armoured beds and interlocked, resilient structures that limit entrainment processes, mobilizing bedload only in response to short-duration/high-intensity rainfall (10 mm hr-1). These channels preserve their morphological structure even under high flow events, triggering sediment transport processes limitedly to peaked storm hydrographs. In the present study we show that the variability in bedload transport among different study reaches is linked to sediment supply conditions and to peculiar hydro-climatic settings. An additional study site characterized by dry conditions, Strimm Creek (Alto Adige, Italy), allows us to obtain a latitudinal transect from dry to wet conditions across the Eastern Italian Alps. By monitoring tracer displacements from 2011 to 2015 at this formerly-glaciated, high-elevation mountain basin, we observe that limited sediment-supply conditions exert a strong control on bedload, chiefly triggered by snowmelt events that account for 73% of the overall travel distances. At Grigno and Tolvà Creeks, also characterized by limited sediment supply, transport is dominated by rainfall events, responsible of driving 95% of the overall travel distances. Sediment availability at Ussaia Creek is responsible for triggering the largest observed bedload events, associated to prolonged autumn precipitation and secondarily to snowmelt events.
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Modelagem da erosão hídrica em latossolos sob cultura de caféMENDES JÚNIOR, Henrique 22 February 2017 (has links)
O solo é um dos principais recursos naturais para a manutenção da vida e dos ecossistemas terrestres. Contudo, problemas relacionados ao uso e manejo inadequados podem acelerar os impactos da erosão hídrica. As perdas de solo e água neste processo causam o carreamento de nutrientes essenciais para o crescimento e manutenção das plantas com interferência na sustentabilidade agropecuária e ambiental. Além disso, podem acarretar impactos nos corpos d’água com o assoreamento e a eutrofização. A estimativa das perdas de solo pela erosão hídrica em sub-bacias hidrográficas é essencial na predição do estágio de degradação do solo, sobretudo em áreas de semi-intensivo cultivo, como as de café. Assim, o objetivo deste trabalho foi modelar as perdas de solo em relação ao limite da Tolerância de Perda de Solo nos Latossolos Vermelho Distróficos sob plantio de café. O estudo foi conduzido de março de 2015 a janeiro de 2017 na Sub-bacia Hidrográfica do Córrego da Laje, Município de Alfenas, na região Sul de Minas Gerais, Sudeste do Brasil. As perdas de solo por erosão hídrica foram estimadas pela Revised Universal Soil Loss Equation e comparadas à Tolerância de Perda de Solo. Para tanto, foram utilizados os atributos morfológicos, físicos e químicos do solo, bem como de técnicas de geoprocessamento, imagens de sensoriamento remoto e dados da literatura especializada. Os resultados demonstram perdas de solo entre 0,01 e 18,77 Mg ha-¹ ano-¹, com média de 1,52 Mg ha-¹ ano-¹. A Tolerância de Perda de Solo variou de 5,19 a 5,90 Mg ha-¹ ano-¹, com 7,35 % da área com perdas acima do limite mínimo. As áreas com declives mais acentuados e ausência de práticas conservacionistas são decisivas para o aumento das perdas de solo acima da Tolerância de Perda de Solo, sendo prioritárias para a adoção de medidas mitigatórias dos efeitos erosivos. A Revised Universal Soil Loss Equation possibilitou modelar a erosão hídrica e identificar, com rapidez, as áreas com as maiores taxas de perdas de solo, o que contribui para a avaliação e conservação dos solos em bacias e sub-bacias hidrográficas. / Soil is one of the main natural resources for maintaining life in terrestrial ecosystems. However, problems related to improper use and management can accelerate the impacts of water erosion. The losses of soil and water in this process cause the carrying of nutrients essential for the growth and maintenance of the plants with interference in agricultural and environmental sustainability. In addition, they can have impacts on water bodies through silting and eutrophication. The estimation of soil losses by water erosion in sub-basins is essential in predicting the soil degradation stage, especially in areas of semi-intensive cultivation, such as coffee. Thus, the aim of this work was to estimate soil losses in relation to the limit of Soil Loss Tolerance in the Red Oxisols Dystrophic under coffee plantation. The study was conducted from March 2015 to January 2017 in the Córrego da Laje Hydrographic Sub-basin, in the municipality of Alfenas, in the southern region of Minas Gerais, Southeastern Brazil. Soil losses due to water erosion were estimated by Revised Universal Soil Loss Equation and compared to Soil Loss Tolerance. For that, the morphological, physical and chemical attributes of the soil were used, as well as geoprocessing techniques, remote sensing images and specialized literature data. The results show soil losses between 0.01 and 18.77 Mg ha-¹ year-¹, with an average of 1.52 Mg ha-¹ year-¹. The Soil Loss Tolerance ranged from 5.19 to 5.90 Mg ha-¹ year-¹, with 7.35% of the area with losses above the minimum limit. Areas with steeper slopes and absence of sustainable practices are decisive for the increase of soil losses above soil loss tolerance, being priority for the adoption of mitigating measures of erosive effects. The Revised Universal Soil Loss Equation has been able to model water erosion and identify the areas with the highest rates of soil loss quickly, which contribute to the assessment and conservation of soils in watersheds and sub-basins.
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Flush foliar na estação seca em floresta de terra firme na Amazônia central via webcamMarostica, Suelen Jorge Felizatto 19 July 2011 (has links)
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Previous issue date: 2011-07-19 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / There is an ongoing debate about the response of Amazon forests to extreme and to normal
seasonal drought. Satellite observed Amazon green-up during the 2005 drought remains
controversial, with green-up attributed by some to cloud/aerosol contamination. Satellite
detection of dry-season green-up in years of normal rainfall is also confounded in the southern
Amazon by decreasing solar zenith angle. To address these concerns by direct assessment of
changes in the forest canopy, a high-resolution (1028x720p) 3-band video camera was
mounted 54 m above the forest floor on an eddy covariance tower 60 km north of Manaus.
Camera aim was south, perpendicular to the solar transit, with an oblique downward view.
Automatic color balance was turned off. For 134 days from the middle of the dry season to
mid rainy season (23 Sept, 2010 to 03 Feb, 2011) one frame was captured every 10s. From
these, a single frame was chosen per day, obtained under diffuse solar illumination near local
noon with minimal variation (< +-10%) in overall reflected scene brightness. Auto-exposure
of the camera compensated this minor variation. Changes in greenness and woodiness were
examined using three approaches: (1) visual classification of transition types for all trees that
underwent marked full-crown changes during the dry season; (2) relative green channel
brightness averaged over the entire frame; and (3) unstandardized Principal Component
Analysis of the entire frame to remove spatial variations in illumination (PC1) and estimate
area of exposed bark (threshold of PC2). Of 13 trees that underwent full-crown transitions in
the first month (dry season), 11 were experiencing some stage of leaf flush . Relative
brightness of the green channel over the entire frame showed that a flush of new leaves was
already taking place at the beginning of the study and continued at least into October, when
leaf maturation caused changes in leaf colors, limiting the usefulness of this indicator. The
area of exposed bark decreased steeply during the mid-dry season leaf flush and further
suggested that leafing-out continued at a slower pace into the rainy season. Due to spectral
stability of exposed bark over time, this is a more reliable indicator of leaf phenology than the
leaves themselves. The results of this study contribute an understanding of what controls
seasonality of vegetation greenness in Amazonia and its photosynthesis response. / Existe um debate em curso sobre a resposta das florestas na Amazônia às secas extremas e às
variações sazonais normais. Observações a partir de um sensor orbital de green-up na
Amazônia durante a seca de 2005 permanecem controversas, com grande parte do fenômeno
atribuído a contaminações por nuvens/aerossóis. Detecção por satélite do green-up no sul da
Amazônia na estação seca foi atribuída ao artefato de sazonalidade no ângulo solar. Para
avaliar mais diretamente as mudanças no dossel de uma floresta de terra firme da Amazônia
Central, utilizou-se uma câmera de vídeo com três bandas na faixa do visível, resolução de
1028x720 pixels, fixa 54 m acima do chão da floresta em uma torre de covariância de fluxo,
60 km ao norte de Manaus. A mira da câmera foi ao sul, perpendicular ao trânsito solar, e
obliqua para baixo. Foi desligada a compensação automática de cor (color-balance). Ao longo
de 134 dias entre o pico da estação seca e o meio da estação chuvosa (23-set, 2010 a 03-fev,
2011), foi capturado um frame a cada 10 s. Foi selecionado ~um frame por dia, sob
iluminação solar difusa, próximo ao meio-dia local e com variação < +/-10% no brilho geral
refletido. A exposição automática da câmera compensou esta variação. As mudanças em
greenness e madeirosidade foram medidas usando três abordagens: (1) classificação visual de
tipos de transição para todas as árvores que experimentaram mudanças na copa por inteiro,
durante o pico da estação seca; (2) médio, em todo o frame, do brilho relativo do canal verde;
e (3) análise de componentes principais, com dados não padronizados, sobre todo o frame,
para remover variações espaciais na iluminação (PC1) e estimar a área de madeira exposta
(limiar do PC2). Das treze árvores que sofreram uma transição completa da copa na estação
seca, onze experimentaram algum estágio de flush foliar. O brilho relativo do canal verde
mostrou que este flush de folhas novas já estava acontecendo no início do estudo e continuou
pelo menos até outubro, quando a maturação das folhas causou mudanças na sua coloração,
limitando o uso desse indicador. A área de madeira exposta diminuiu abruptamente durante a
estação seca e continuou caindo em ritmo menor no decorrer da estação chuvosa. Este
indicador foi considerado mais confiável, devido a sua estabilidade espectral. Os resultados
deste estudo contribuem para o entendimento da real sazonalidade de greenness da vegetação
na Amazônia e sua resposta à fotossíntese.
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Proposta metodolÃgica de gestÃo dos espaÃos-riscos de inundaÃÃes urbana em MossorÃ-RN / methodology proposed for management of flood - risk areas in urban mossorà -rnAlexsandra Bezerra da Rocha 28 May 2015 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Inserida na temÃtica de risco associados à inundaÃÃo urbana sobre a realidade de uma cidade potiguar do semiÃrido nordestino brasileiro. Tendo como objetivo o estudo da dinÃmica climÃtica - hidrolÃgica frente a situaÃÃes de emergÃncia e estado de calamidade pÃblica (estiagens e inundaÃÃes), com Ãnfase na metodologia de delimitaÃÃo das Ãreas de risco de inundaÃÃes urbanas considerando as caracterÃsticas meteorolÃgicas e os efeitos econÃmicos e sociais na vida da populaÃÃo atingida. Os principais conceitos discutidos: perigo, risco, desastre, catÃstrofe, vulnerabilidade e eventos extremos. A metodologia consistiu na pesquisa documental, de bancos de dados, e ainda pesquisa de campo, anÃlise e interpretaÃÃo da evoluÃÃo urbana e dinÃmica climÃtica, delimitaÃÃo dos espaÃos-risco de inundaÃÃo urbana em Mossorà obedecendo aos seguintes recortes temporais: dados urbanos (1970-2010), climÃticos (1970-2013), defesa civil de Mossorà (1983-2013). A gestÃo do risco em discussÃo està voltada ao mapeamento, prevenÃÃo, monitoramento, alerta e resposta. Na sÃrie em anÃlise encontrou-se 18 eventos extremos, destes 16 anos foi decretado situaÃÃo de emergÃncia e 2 estado de calamidade pÃblica. Adotou-se tambÃm metodologia que possibilita a delimitaÃÃo dos espaÃos-risco de inundaÃÃo no nÃcleo urbano de Mossorà e populaÃÃo atingida por setor censitÃrio. A metodologia mostrou que o uso das imagens ASTERGDEM na resoluÃÃo de 30 metros sÃo ferramentas interessantes para definiÃÃo das Ãreas de risco de inundaÃÃo, uma vez que atravÃs de programas como Qgis 2.8 e Arcgis 10.1 existe a possibilidade da aplicaÃÃo de filtros para diminuir os ruÃdos da imagem, bem como a suavizaÃÃo das curvas de nÃvel. Encontrou-se duas zonas a primeira com inundaÃÃo mÃxima nas cotas de 15 metros e a menor entre 7 e 13 metros. O cruzamento e delimitaÃÃo com os setores censitÃrios mostrou que 67 setores sÃo diretamente atingidos, sendo que 35.775 pessoas estÃo na primeira zona (atà 15 metros) e 8.364 pessoas estÃo na segunda zona (7 a 13 metros). Sendo que os setores com maior nÃmero de pessoas em risco sÃo: Barrocas 10.708 pessoas, Belo Horizonte 6.353, Alto da ConceiÃÃo 5.306, ParedÃes 5.187, Ilha de Santa Luzia, Lagoa do Mato 2.015, Pintos 1.436., Bom Jardim 1.430 e Alto de SÃo Manoel 1.153. Neste contexto foi elaborada uma proposta para o plano de contingÃncia à inundaÃÃo considerando os bairros mais atingidos. A valorizaÃÃo dos espaÃos-risco, como tradutores de expressÃo dos potenciais perigos, promove a adequaÃÃo e assegura recursos e meios para a proteÃÃo e socorro, favorece tambÃm a infraestruturaÃÃo da saÃde e o apoio social (quantitativamente e qualitativamente) das Ãreas perigosas / This research is within the topic of risk associated with urban floods in a semiarid northeast Brazilian city. The aim of the research is the study of climate dynamics â hydrological (droughts and floods) in situations of emergency and a state of emergency. The research focuses on the methodology of delimitation of urban floods considering the weather and its economic and social impacts on the lives of the affected population. The concepts discussed are: hazard, risk, disaster, catastrophe, vulnerability and extreme events. The methodology used is based on review of existing documentation, database and fieldwork, analysis and interpretation of urban evolution and climatic dynamics and delimitation of flood risky spaces in Mossorà with the following timeframes: urban data (1970-2010), climatic (1970-2013), Mossorà civil defense (1983-2013). The risk management approach in discussion is related to risk mapping, prevention, monitoring, alert and response. Within the analyzed series, 18 events were found, among them 16 were declared as situation of emergency and 2 as state of emergency. This research explores a methodology that enables the definition of flooding areas in the urban core of Mossorà andpeople at risk through the census tracts. The methodology showed that the use of ASTERGDEM images with the resolution of 30 meters is an interesting approach for definition of flooding areas, given that, with the use of Qgis 2.8 and Arcgis 10.1 there is a possibility of application of filters to reduce noise from the images as well as smoothing the contours. Two regions were found, the first with the maximum flood at an altitude of 15 meters and the lowest between 7 and 13 meters. The intersection and delimitation with census tracts shows that 67 census tracts are daily affected, with 35.775 people living in the first region (up to 15metres) and 8.364 people are in the second region (7-13 metres), the sectors with the largest number of people at risk are: Barrocas 10.708 people, Belo Horizonte 6.353, Alto da ConceiÃÃo 5.306, ParedÃes 5.187, Ilha de Santa Luzia, Lagoa do Mato 2.015, Pintos 1.436., Bom Jardim 1.430 e Alto de SÃo Manoel 1.153. As a result a contingency plan was proposed considering the most affected neighborhoods. The appreciation of the risky areas, as an expression of the potential hazards, promotes fitness and ensures resources and means for the protection and relief, also favors health and social support (quantitatively and qualitatively) in dangerous areas
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Análise espaço temporal do uso e cobertura da terra no entorno da BR-101 - trecho Angra dos Reis e Parati/RJ / Analysis space weather of the use and covering of the land in around of the BR-101 - stretch Angra dos Reis and Parati/RJStella Procopio da Rocha 15 December 2005 (has links)
A valorização e preservação do meio-ambiente tem sido bastante discutida, e cada vez mais tem sido parte integrante de projetos de diferentes grupos de interesse que buscam um desenvolvimento sustentável. Dentro deste contexto da busca pelo desenvolvimento sustentável e de políticas ambientais eficazes, surge outro termo que irá englobar uma série de ações preventivas e de gerenciamento do meio ambiente: o planejamento ambiental. Levantamentos ambientais, inerentes ao planejamento ambiental são realizados de diferentes maneiras, e neste contexto, inclui-se a utilização de novas tecnologias como o uso de produtos do Sensoriamento Remoto e Sistema de Informação Geográfica (SIG), que têm auxiliado na otimização do processamento e da precisão de resultados devido à ampliação na velocidade de obtenção de dados e na capacidade de armazenamento de informações, bem como o uso de imagens de sensores orbitais que tem apresentado diversas utilidades no âmbito dos estudos da Terra, nos mais variados tipos de avaliação ambiental. A partir de tais considerações foi possível elaborar uma linha de atuação a partir da análise espaço-temporal com a utilização do sensoriamento remoto aplicado em uma porção do território que vem passando por transformações significativas nas últimas décadas. Dessa maneira, pensou-se em realizar a análise de uma área que apresenta uma grande potencialidade para a atividade turística e um crescimento industrial importante e que tem alterado sua paisagem nas duas últimas décadas. O trecho em questão é o que liga os municípios de Angra dos Reis e Parati, no litoral Sul do Estado do Rio de Janeiro. Nos dois casos têm-se como importante fonte de renda, o turismo ecológico, que têm atraído empreendimentos imobiliários de grande porte para a região, além do turismo cultural. O objetivo deste trabalho é analisar o grau de transformação do uso e cobertura da terra no entorno da Rodovia Rio-Santos neste trecho, nos últimos vinte anos, dando ênfase a três datas: 1984, 1994 e 2002. Parte-se da hipótese que tais transformações têm-se intensificado, estimulando maiores investimentos voltados ao turismo, pressionando os remanescentes de Mata Atlântica.. Através da análise espaço-temporal do uso e cobertura da terra no período e sua estruturação em um banco de dados, obteremos um retrato atual da região que pode servir como ponto de partida para o planejamento de uso e ocupação da terra, avaliando a forma atual da ocupação, evitando assim que seus recursos naturais sejam usufruídos de forma errônea podendo promover a degradação ou mesmo a extinção dos mesmos. / The environmental valuation and preservation has been sufficiently discussed, and it has been part of projects of different groups of interest that search for a sustainable development. Inside of this context of searching for a sustainable development and for efficient environmental politics, another term appears that involves a series of actions and management of the environment: the environmental planning. Environmental surveys are realized in different ways, and in this context it is common the use of new technologies such as Remote Sensing products and Geographic Information Systems (SIG). These technologies, which allow digital image processing and produce results with better precision as well as the use of images from orbital sensors, have presented diverse utilities in the scope of land use studies, in varied types of environmental evaluations. From such consideration it was possible to elaborate a research that begun with a time-space analysis using remote sensing products in a portion of the territory that is passing through significant transformations in the last decades. In this way, one thought about carrying through the analysis of an area that presents a great potentiality for tourism activity and also important industrial growth and that it has modified its landscape in the two last decades. The issue stretch in question is what it binds to the cove cities Angra dos Reis and Parati, in the South coast of the state of Rio de Janeiro. In these two cases they are had as important source of income, the ecological tourism, that have attracted real estate enterprises of great transport for the region, beyond the cultural tourism. The objective of the present work was to analyze the dynamic of the landscape produced by human transformations in tree different buffers from the Rio-Santos highway in the last twenty years and in three different years: 1984, 1994 and 2002. The hypothesis was that such transformations have been intensified, stimulated by the tourism, threatening the Atlantic forest fragments remnants. Through a time-space analysis of land use it was possible to present the landscape dynamic between two decades as a starting point for an environmental planning of the land use, evaluating the current form of occupation, thus preventing that the local natural resources will be usufructed of error form being able to promote the same degradation or the extinguishing of the same ones.
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