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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Möglichkeiten der Nutzung thermal-infraroter Wellenlängen zur fernerkundlichen Erfassung/Quantifizierung von Bodenparametern in semiariden Agrarregionen

Eisele, Andreas 24 February 2014 (has links)
In der vorliegenden Arbeit werden die Möglichkeiten einer Nutzung thermal-infraroter Wellenlängen zur fernerkundlichen Erfassung/Quantifizierung von Bodenparametern vorgestellt. Die Studie basiert auf Bodenproben des Untersuchungsgebietes Mullewa, welches sich in einer semiariden Agrarregion im West-Australischen Weizengürtel befindet. Im Mittelpunkt der Arbeit steht die Bewertung des langwelligen Infrarots (LWIR), innerhalb des atmosphärischen Fensters zwischen 8 und 14 Mikrometer, bezüglich seines spektralen Potentials für die quantitative Ableitung des Ton- und Sandgehaltes sowie des Gehaltes an organischem Kohlenstoff (SOC). Zur Abschätzung der Effizienz wurden die Ergebnisse des LWIR einer Quantifizierung aus dem herkömmlich gebrauchten solar-reflektiven Wellenlängenbereichs zwischen 0,4 und 2,5 Mikrometer (VNIR-SWIR) gegenübergestellt. Mit verschiedenen Methoden der Laborspektroskopie wurden Bodenproben aus dem Untersuchungsgebiet im thermalen (Emissions-FTIR-Spektroskopie und direktional-hemisphärische Reflexions- (DHR) Spektroskopie)und im solar-reflektiven (Diffuse Reflexions-Spektroskopie) Wellenlängenbereich eingemessen und anschließend auf ihren Informationsgehalt hin untersucht. Die quantitative Modellierung der pedologischen Parameter aus den gemessenen spektralen Signaturen wurde mithilfe einer multivariaten Regressionsanalyse (Partial Least Squares Regression – PLSR) realisiert. Diese Grundlagenstudie konnte zeigen, dass die spektralen Voraussetzungen im LWIR für ein mögliches Monitoring der Bodenparameter mit thermalen Fernerkundungsdaten gegeben sind. Die Arbeit demonstriert darüber hinaus, dass für die Erfassung/Quantifizierung der Textur-Parameter (Sand- und Tongehalt) der relevante spektrale Informationsgehalt im LWIR deutlich höher ist als im VNIR-SWIR. / This study embraces the feasibility of using the thermal infrared wavelength region for future remote sensing applications to detect/quantify soil parameters. The research is based on soil samples from the semiarid agricultural area of Mullewa, located within the wheat belt of Western Australia. The main focus of this study is to assess the potential of the longwave infrared (LWIR), within the atmospheric window between 8 and 14 micrometer, to predict the content of sand, clay and organic carbon (SOC) in soils. The results are compared with predictions made with the traditionally used solar-reflective wavelength region (visible, VIS: 0.4 - 0.7 micrometer; near infrared, NIR: 0.7 - 1.1 micrometer; shortwave infrared, SWIR: 1.1 - 2.5 micrometer). Using laboratory spectroscopy, the Mullewa soil samples were measured, both in the thermal infrared (emission FTIR spectroscopy and directional hemispherical reflection (DHR) spectroscopy) and in the solar-reflective (diffuse reflection spectroscopy) wavelength region. This data was analyzed to determine the relevant content of information for the soil parameters. Multivariate regression analyses (partial least squares regression - PLSR) were used to quantitatively model the soil parameters from the spectral signatures. This basic research demonstrated that the spectral requirements in the LWIR are met for monitoring these soil parameters with thermal remote sensing instruments. Furthermore the study found that the relevant spectral information for the detection/quantification of the sand- and the clay content (textural parameters) is explicitly higher in the LWIR than in the VNIR-SWIR.
172

Contribuição ao conhecimento limnológico de reservatórios do semi-árido brasileiro que abastecem a região metropolitana de Fortaleza: Açudes Pacajus e Gavião (Ceará, Brasil) / Contribution to limnological knowledge of brazilian semi-arid reservoir that supply Fortaleza\'s metropolitan region: Pacajus and Gavião dams (Ceará, Brazil)

Freire, Rogério Herlon Furtado 08 October 2007 (has links)
O principal objetivo deste estudo foi investigar a influência das alterações nas condições climáticas e hidrodinâmicas sobre a estabilidade física, a disponibilidade de recursos, a estrutura da comunidade zooplanctônica e os padrões de heterogeneidade espacial dos açudes Pacajus e Gavião, amostrados bimestralmente entre nov. 1988 e dez. 1998. Nos dois reservatórios os pontos foram distribuídos ao longo dos respectivos eixos longitudinais principais, sendo 06 no açude Pacajus e 05 no Gavião. As medidas de temperatura da água, condutividade elétrica, turbidez, pH e oxigênio dissolvido (OD) foram realizadas em intervalos regulares da coluna d\'água com o uso de sonda multiparamétrica (HORIBA U-10). Amostras para determinação de alcalinidade total, nutrientes inorgânicos dissolvidos e fósforo total foram coletadas em profundidades correspondentes à superfície, meio e fundo da coluna d´água. A determinação de clorofila a foi realizada em amostras de superfície. A estrutura vertical dacoluna d\'água dos reservatórios foi caracterizada por pequenos gradientes térmicos e salinos, especialmente durante o segundo semestre, quando o vento atuou como principal forçante indutora de mistura turbulenta. Nessa época do ano as concentrações de OD foram típicas de supersaturação nos dois reservatórios. A dinâmica de nutrientes nos açudes Pacajus e Gavião dependeu das contribuições alóctones durante o período chuvoso e dos processos de regeneração e carga interna durante o período de estiagem. O maior grau de enriquecimento e biomassa algal observados no açude Pacajus classificou-o como eutrófico-hipereutrófico, enquanto que o açude Gavião foi classificado como meso-eutrófico. A heterogeneidade espacial dos reservatórios foi condicionada pelo regime hidrológico do rio barrado, no caso do açude Pacajus, pelos gradientes hidráulicos ao longo ) do eixo longitudinal, pela influência dos procedimentos de transferências hídricas internas, especialmente no açude Gavião, e pela irregularidade na distribuição espacial do fitoplâncton, acompanhando gradientes tróficos. De modo geral, pode-se afirmar que as espécies do zooplâncton identificadas nos açude Pacajus e Gavião são bem representativas da fauna de microinvertebrados planctônicos Neotropical, com amplo espectro de distribuição geográfica no Brasil. A dominância dos Rotifera no açude Pacajus em dez. 1998 foi indicativo das condições hipereutróficas da maioria dos pontos amostrados. Espacialmente, os organismos desse grupo, representados principalmente por espécies dos gêneros Brachionus e Keratella, indicadores de ambientes nutriente-enriquecidos, foram mais abundantes nos compartimentos com estado trófico superior. Comportamento similar foi observado para o Copepoda Cyclopoida Thermocyclops decipiens, espécie indicadora de condições eutróficas, a qual colonizou, preferencialmente, regiões com maior concentração de nutrientes. Ao contrário, organismos dos grupos Copepoda e Cladocera foram mais abundantes nas regiões menos enriquecidas dos reservatórios, apresentando gradientes longitudinais inversos em relação àqueles dos Rotifera e Cyclopoida. Portanto, a distribuição e os padrões de dominância do zooplâncton nos açudes Pacajus e Gavião foram condicionadas, principalmente, pela variabilidade espaço-temporal dos gradientes tróficos. / The main aim of this research was to investigate the influence of climatic and hydrodynamics\' alterations about physical stability, resources availability, zooplankton community structure and spatial heterogeneity standard of Pacajus and Gavião dams, collected at two-month period between Nov. 1988 and Dec. 1998. In the reservoirs, the sample stations were distributed along the main longitudinal axis, being six on Pacajus dam and five on Gavião dam. Water temperature, electric conductivity, turbidity, pH and dissolved oxygen were measured in regular intervals in water column using a multiparametric probe (HORIBA U-10). Sample for total alkalinity, inorganic dissolved nutrients and total phosphorous determination were collected in the corresponding depth in water column (surface, middle and deep). Chlorophyll a determination was measured in surface samples. Vertical structure of water column in reservoirs was characterized by little thermal and saline gradients, especially duringsecond semester, when wind was the main induced force of turbulent mixture. At this same period dissolved oxygen concentrations were typical supersaturated on both reservoirs. Nutrients dynamic on both dams were dependent on allocthonous contributions during rainy season and on regeneration processes and internal load during dry season. The greatest rank of enrichment and algal biomass measured in Pacajus\' dam classified it as eutrophic or hipereutrophic while Gavião\'s dam was mesotrophic or eutrophic. Spatial heterogeneity of reservoirs was controlled by hydrological regime of the dammed river in case of Pacajus\' dam, by hydraulic gradients along main axis and the influence of internal hydraulic transferences proceedings in the case of Gavião\'s dam and by irregularity on phytoplankton spatial distribution according to trophic gradients. In general, it can be said that zooplankton species ) identified on both dams are representative of Neotropical plankton micro invertebrate fauna, with large geographic distribution in Brazil. The dominance of rotifers in Pacajus\' dam on Dec. 1998 was favored by hipereutrophic conditions in most of sample stations. Especially, this group of organisms, represented mainly by Brachionus and Keratella, indicators of nutrient enriched environments, were abundant in segments with higher trophic state. Similar behavior was observed to the copepod Thermocyclops decipiens, an indicator of eutrophic conditions, which has colonized regions with higher nutrient concentrations. On the other hand, Copepoda and Cladocera were more abundant on poorer nutrient compartiments of reservoirs, presenting inverse longitudinal gradients in relation with those of Rotifera and Cyclopoida. Therefore, distribution and patterns of zooplankton dominance in Pacajus and Gavião dams were conditioned mainly by spatial-temporal variability of trophic gradients.
173

Exploring the use of conceptual catchment models in assessing irrigation water availability for grape growing in the semi-arid Andes / Apport des modèles hydrologiques conceptuels à l’estimation de la disponibilité en eau pour l’irrigation de la vigne dans les Andes semi-arides

Hublart, Paul 30 November 2015 (has links)
La thèse explore l’utilisation de modèles hydrologiques globaux pour estimer la disponibilité en eau agricole dans le contexte des Andes chiliennes semi-arides. Dans cette région, l’approvisionnement en eau des cultures irriguées de fonds de vallée durant l’été dépend de précipitations se produisant sous forme de neige à haute altitude lors de quelques évènements hivernaux. L’influence des phénomènes ENSO et PDO induit par ailleurs une forte variabilité climatique à l’échelle inter-annuelle, marquée par l’occurrence d’années extrêmement sèches ou humides. La région connaît aussi depuis les années 1980 une progression importante de la viticulture irriguée. Afin de prendre en compte les variations saisonnières et inter-annuelles de la disponibilité et de la consommation en eau d’irrigation, une chaîne de modélisation intégrée a été développée et différentes méthodes de quantification/réduction des incertitudes de simulation ont été mises en œuvre. Les écoulements naturels ont été simulés avec un modèle hydrologique global de type empirique/conceptuel prenant en compte les processus d’accumulation et d’ablation de la neige. En parallèle, les besoins en eau d’irrigation ont été estimés à l’échelle du bassin à partir de modèles phénologiques orientés processus et d’une approche simple du bilan hydrique du sol. Dans l’ensemble, une approche holistique et parcimonieuse a été privilégiée afin de maintenir un niveau d’abstraction mathématique et de représentation des processus équivalent à celui des modèles de bassin couramment utilisés. Afin d’améliorer l’utilité et la fiabilité des simulations obtenues en contexte de changement ou de forte variabilité climatique, l’effet des températures extrêmes sur le développement des cultures et l’impact des pertes en eau par sublimation à haute altitude ont fait l’objet d’une attention particulière. Ce cadre de modélisation conceptuel a été testé pour un bassin typique des Andes semi-arides (1512 km2, 820–5500 m a.s.l.) sur une période de 20 ans incluant une large gamme de conditions climatiques et des pratiques agricoles non-stationnaires (évolution des variétés de vigne, des surfaces et modes d’irrigation, etc). L’évaluation des modèles a été réalisée dans un cadre bayésien en faisant l’hypothèse d’erreurs auto-corrélées, hétéroscédastiques et non-gaussiennes. Différents critères et sources de données ont par ailleurs été mobilisés afin de vérifier l’efficacité et la cohérence interne de la chaîne de modélisation ainsi que la fiabilité statistique et la finesse des intervalles de confiance obtenus. De manière alternative, une caractérisation des erreurs de structure et de l’ambiguïté propre au choix du modèle hydrologique a été réalisée de manière non-probabiliste à partir d’une plate-forme de modélisation modulaire. Dans l’ensemble, la prise en compte explicite de la consommation en eau des cultures a mis en valeur certaines interactions entre paramètres hydrologiques et permis d’améliorer la fiabilité des simulations hydrologiques en année sèche. Finalement, une étude de sensibilité à différents seuils d’augmentation de la température et de la concentration en CO2 a été effectuée afin d’évaluer l’impact potentiel des changements climatiques sur le comportement de l’hydrosystème et la capacité à satisfaire la demande en eau d’irrigation dans le futur. / This thesis investigates the use of lumped catchment models to assess water availability for irrigation in the upland areas of northern-central Chile (30°S). Here, most of the annual water supply falls as snow in the high Cordillera during a few winter storms. Seasonal snowpacks serve as natural reservoirs, accumulating water during the winter and sustaining streams and aquifers during the summer, when irrigation demand in the cultivated valleys is at its peak. At the inter-annual timescale, the influence of ENSO and PDO phenomena result in the occurrence of extremely wet and dry years. Also, irrigated areas and grape growing have achieved a dramatic increase since the early 1980s. To evaluate the usefulness of explicitly accounting for changes in irrigation water-use in lumped catchment models, an integrated modeling framework was developed and different ways of quantifying/reducing model uncertainty were explored. Natural streamflow was simulated using an empirical hydrological model and a snowmelt routine. In parallel, seasonal and inter-annual variations in irrigation requirements were estimated using several process-based phenological models and a simple soil-water balance approach. Overall, this resulted in a low-dimensional, holistic approach based on the same level of mathematical abstraction and process representation as in most commonly-used catchment models. To improve model reliability and usefulness under varying or changing climate conditions, particular attention was paid to the effects of extreme temperatures on crop phenology and the contribution of sublimation losses to water balance at high elevations. This conceptual framework was tested in a typical semi-arid Andean catchment (1512 km2, 820–5500 m a.s.l.) over a 20–year simulation period encompassing a wide range of climate and water-use conditions (changes in grape varieties, irrigated areas, irrigation techniques). Model evaluation was performed from a Bayesian perspective assuming auto-correlated, heteroscedastic and non-gaussian residuals. Different criteria and data sources were used to verify model assumptions in terms of efficiency, internal consistency, statistical reliability and sharpness of the predictive uncertainty bands. Alternatively, a multiple-hypothesis and multi-criteria modeling framework was also developed to quantify the importance of model non-uniqueness and structural inadequacy from a non-probabilistic perspective. On the whole, incorporating the effects of irrigation water-use led to new interactions between the hydrological parameters of the modeling framework and improved reliability of streamflow predictions during low-flow periods. Finally, a sensitivity analysis to changes in climate conditions was conducted to evaluate the potential impacts of increasing temperatures and atmospheric CO2 on the hydrological behavior of the catchment and the capacity to meet future water demands.
174

Perfil fermentativo de forrageiras nativas da caatinga

Santos, Maria do Socorro Almeida Arnaldo 28 September 2018 (has links)
Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The objective of this study was to characterize the nutritional potential of five native forage species of the caatinga through the in vitro gas production technique. The experimental design was in 5 x 2 factorial blocks, with five forage species: (Catingueira, Maniçoba, Marmeleiro, Quixabeira, Faveleira), with no addition of polyethylene glycol (PEG). The chemical-bromatological appearance was seen; disappearance, digestibility and cumulative in vitro gas production of organic matter, in addition to ruminal parameters. There is no significant interaction as species and treatment (with and without PEG). Based on the results of a faveleira, comparing them with other species, we can highlight the bromatological comparison of raw material, with superior and inferior fibers in neutral detergent (NDF), acid detergent fiber (FAD) and Lignin, resulting in a better DIVMO coefficient and higher gas accumulation. However, all species have increased the digestibility (above 60%), with the value of NNH3, FP, and microbial biomass, thus demonstrating a good fermentative efficiency. The inhibition of condensed tannins (increase of PEG) influenced in a significant way in a DIVMO, PGMO and biomass production, thus making a good efficiency of ruminal fermentation kinetics. good ruminal fermentation, and can be used for animal feed without semiarid. / Objetivou-se caracterizar o potencial nutricional de cinco espécies forrageiras nativas da caatinga através da técnica de produção de gás in vitro. O delineamento experimental foi em Blocos Casualizados (série de incubação) em esquema fatorial 5 x 2, sendo cinco espécies de forrageiras: (Catingueira, Maniçoba, Marmeleiro, Quixabeira, Faveleira), com e sem a adição de polietilenoglicol (PEG). Foram analisados a composição químicabromatológica; desaparecimento, digestibilidade e produção cumulativa de gás in vitro da matéria orgânica, além dos parâmetros ruminais. Não houve interação significativa entres as espécies e o tratamento (com e sem PEG). Mediante os resultados a faveleira, comparado com as demais espécies, destacou-se por apresentar uma composição bromatológica de relevância, com PB superior e baixa fibra em detergente neutro (FDN), fibra em detergente ácido (FDA) e Lignina, acarretando em um melhor coeficiente de DIVMO e maior acumulo de gás. Entretanto, todas a espécies apresentaram alta taxa de digestibilidade (acima de 60%), valores considerados ideias de N-NH3, FP, e produção de biomassa microbiana, demostrando assim uma boa eficiência fermentativa. A inibição dos taninos condensados (adição de PEG) influenciou nos parâmetros aumentando significativamente a DIVMO, PGMO e produção de biomassa, indicando assim uma boa eficiência da cinética da fermentação ruminal.Todas a espécies apresentaram característica nutricionais (pela técnica in vitro) favoráveis para uma boa fermentação ruminal, podendo ser utilizadas para alimentação animal no semiárido. / São Cristóvão, SE
175

EVOLUÇÃO TEMPORAL DOS NÍVEIS TRÓFICOS DO AÇUDE EPITÁCIO PESSOA, SEMI-ÁRIDO PARAIBANO

Araújo Júnior, Ronaldo Justino de 17 September 2009 (has links)
Made available in DSpace on 2015-09-25T12:23:38Z (GMT). No. of bitstreams: 1 Ronaldo Justino de Araujo Junior.pdf: 1045639 bytes, checksum: 74c1ae9be07d1e1244c7e92e41b32bb8 (MD5) Previous issue date: 2009-09-17 / The eutrophication process on water bodies, resulting of anthropogenic activities, is one of more serious problems of degradation of water quality, limiting its use for various purposes. The evaluation of trophic state has produced satisfactory results for the management of water resources. This study aimed to study the water quality of Epitácio Pessoa dam PB, between the years 1989 to 2008 and assess the trend of the evolution of trophic levels. The information in this study were from the database of the Laboratory of Aquatic Ecology LAE of Paraíba State University on the period 2005 to 2008 and Ph.D. theses developed between 1989 and 2003. The water temperature ranged between 23.6 C and 29.6 º C, with higher values between 2003 and 2008. The average pH ranged between 7.4 and 9.11 higher in the dry season. The electrical conductivity was highest between 2002 and 2003 (525μS/cm the 633μS/cm), when the volume stored in the reservoir was reduced to 35.4% of capacity. The highest concentrations of dissolved oxygen occurred between 1989 and 1991 (average > 8.0 mg / L). The average concentrations of ammonia were higher between 1991 and 2003, during which the dam had less volume of water. Nitrates were higher between 1989 and 2003, decreased between 2005 and 2006 resulting in the delivery of large volumes of water. The total phosphorus ranged from 4 μg/L and 125 μg/L, higher between 1991 and 2003. Between 1989 and 1991 chlorophyll "a" had the highest values in the rainy season, between 3.3 μg/l and 6.7 μg/l. From the rain 3 (2002), the highest concentrations occurred in the dry season. The Epitácio Pessoa dam was classified as oligo-mesotrophic (1989 - 1991), mesotrophic (2002 - 2003), oligotrophic (2005 - 2007) and oligo-mesotrophic (2008), showing a higher trophic gradient in the period of greatest reduction in volume, reflecting the increased concentrations of nutrients. The variables that correlated with changes in STI-average, were the total phosphorus, soluble orthophosphate and transparency. The information generated in this study could support future action planning and management of the waters of the Epitácio Pessoa dam, a major source of drinking water in the state of Paraíba. / O processo de eutrofização nos corpos aquáticos, resultante das atividades antropogênicas, constitui um dos problemas mais graves de degradação da qualidade da água, limitando seu uso para diversos fins. A avaliação do estado trófico tem produzido resultados satisfatórios para o manejo dos recursos hídricos. Esse estudo teve como objetivos estudar a qualidade da água do açude Epitácio Pessoa - PB entre os anos de 1989 a 2008 e avaliar a tendência da evolução dos níveis tróficos. As informações desse estudo foram provenientes da base de dados do Laboratório de Ecologia Aquática LEAq da Universidade Estadual da Paraíba no período de 2005 a 2008 e de teses de doutorado desenvolvidas entre 1989 e 2003. A temperatura da água variou entre 23,6ºC e 29,6ºC, com maiores valores entre 2003 e 2008. O pH médio variou entre 7,4 e 9,11 mais elevado na estiagem. A Condutividade Elétrica esteve mais alta entre 2002 e 2003 (525μS/cm a 633μS/cm), quando o volume armazenado no açude foi reduzido a 35,4% da capacidade. As maiores concentrações de oxigênio dissolvido, ocorreram entre 1989 e 1991 (médias > 8,0mg/L). As concentrações médias de nitrogênio amoniacal foram mais elevadas entre 1991 e 2003, período em que o açude contava com menor volume de água. Os nitratos foram mais elevados entre 1989 e 2003, com diminuição entre 2005 e 2006 resultante do aporte de grande volume de água. O fósforo total variou entre 4 μg/L e 125 μg/L, mais elevado entre 1991 e 2003. Entre 1989 e 1991 a clorofila a apresentou os maiores valores médios nas épocas chuvosas, entre 3,3 μg/l e 6,7 μg/l. A partir da chuva 3 (2002), as maiores concentrações ocorreram na estiagem. O açude Epitácio Pessoa classificou-se como oligo-mesotrófico (1989 1991), mesotrófico (2002 2003), oligotrófico (2005 2007) e oligo-mesotrófico (2008), evidenciando um maior gradiente trófico no período de maior redução do volume, repercutindo no aumento das concentrações dos nutrientes. As variáveis que melhor correlacionaram-se com as variações do IET-Médio, foram o fósforo total, o ortofosfato solúvel e a transparência. As informações geradas nesse estudo poderão subsidiar ações futuras de planejamento e gerenciamento das águas do açude Epitácio Pessoa, importante fonte de água para consumo humano no Estado da Paraíba.
176

DIVERSIDADE, BIOMASSA AÉREA E ESTIMATIVA DO ESTOQUE DE CARBONO EM PLANTAS DA CAATINGA EM UM REMANESCENTE SERRANO NO TRÓPICO SEMI-ÁRIDO / DIVERSITY, AND AERIAL BIOMASS ESTIMATE OF STOCK CARBON IN PLANTS OF CAATINGA IN A REMAINING MOUNTAIN IN SEMI-ARID TROPICS

Souza, Bruno Cruz de 31 August 2009 (has links)
Made available in DSpace on 2015-09-25T12:23:38Z (GMT). No. of bitstreams: 1 Bruno Cruz de Souza.pdf: 532343 bytes, checksum: 8dec8be4074dd0c056e30ae071d41e56 (MD5) Previous issue date: 2009-08-31 / Among the remaining existing mountainous areas have not yet been characterized for their composition and structure, it is believed that these remnants harbor a high biological diversity. Seeking to expand the knowledge phytoecological caatinga, particularly mountainous areas, this study assessed the species richness, diversity and plant community structure present and, through mathematical models propose drawing the allometric equation for estimating carbon stock in plants of the caatinga. The location of the study was the Serra da Arara in the municipality of São João do Cariri micro Cariri West. The land use history showed that there occurred 40 years extraction of firewood and currently the vegetation is retained. To phytosociological sampling was adopted the usual inclusion criteria for this type 11 of vegetation, characterized by the method of point-and-quadrant, which consisted of randomly selecting 30 sample units, and each plant chosen 6-point. The calculated parameters of diversity were the index of Shannon diversity, richness of taxa, equitability and richness estimators nonparametric Chao 1 and Jackknife 1. For structural analysis were determined by the total density and basal area, and the species in diameter classes and high, estimated to determine the projection area and canopy biomass was used the allometric equations, Copa (m2) = 0 , 1939 x diameter (cm) 1.6311 and Biomass Kg = 0.2627 DAP 1.9010. To elaborate the allometric equation of carbon stock, depending on the measures and DNS HT were tested regression models simple and multiple linear, logarithmic, exponential, geometric and power function. All data were processed by the software Native forest 2 and Bioestat 5.0. It was recorded 32 species in 11 families who had a rate of taxon richness and diversity of 4.86 Shannon 2.71. Values considered high when compared with work done on other studies of caatinga. The structural parameters showed low values, density (2.395 planta/ha-1), basal area (6.69 m2/ha-1), average height and diameter (3.52 and 8.67 cm), crown area ( 5872 m2 ha-1) and biomass (16.3 kg ha-1). The dominant species were the shrub layer, confirming that the vegetation in Old Cariris presents a face-sized specimens with "low" and are distributed in a scattered way, it is open, however, their diversity is high probably because we it is a mountainous area, indicating that these areas are conserved and thus play role of buffer zones for these locations. After testing the equation modeling carbon stock, it was observed that the variable total height (HT) when evaluated alone showed low values for the coefficient of determination R2 is not recommended for estimating carbon stock (CS). DNS showed the best correlation with the CS, however, the values obtained for the coefficient of determination were insufficient and can explain only 40% of variations. The combination of the DNS with HT resulted in improvement in the value of the coefficient. The models that were best suited to the type potency (CS = a DNS b) and linear regression and multiple (CS = a + bX), however, the small sample did not arrive at an equation for greater accuracy, which allow us to estimate the potential carbon storage in plants of the caatinga. / Dentre os remanescentes existentes, as áreas serranas ainda não foram caracterizadas quanto a sua composição e estrutura, acredita-se que esses remanescentes abrigam uma elevada diversidade biológica. Objetivando ampliar o conhecimento fitoecológico da caatinga, em especial das áreas serranas, nesse estudo avaliou-se a riqueza de espécies, diversidade e estrutura da comunidade vegetal presente e, através de modelos matemáticos propor a elaboração da equação alométrica para estimativa do estoque de carbono em plantas da caatinga. A localidade do estudo foi a Serra da Arara no município de São João do Cariri, microrregião do Cariri Ocidental. O histórico de uso apontou que há 40 anos ocorreu extração de lenha e atualmente a vegetação encontra-se conservada. Para amostragem fitossociológica foi adotado os critérios de inclusão usuais para esse tipo de vegetação, sendo caracterizada 10 pelo método do ponto-e-quadrante, que consistiu na escolha aleatória de 30 unidades amostrais e em cada uma delas escolhidas 6 plantas-ponto. Os parâmetros calculados de diversidade foram o índice de diversidade de Shannon, riqueza de táxons, equabilidade e os estimadores de riqueza não-paramétricos Chao 1 e Jackknife 1 . Para análise estrutural foram determinadas a densidade total e área basal total, sendo as espécies distribuídas em classes de diâmetro e de altura, para determinação estimada da área de projeção de copa e da biomassa, foi utilizadas as equações alométricas, Copa (m2) = 0,1939 x diâmetro (cm)1.6311 e Biomassa Kg = 0,2627. DAP 1,9010. Para elaboração da equação alométrica de estoque de carbono, em função das medidas de DNS e HT, foram testados os modelos de regressão linear simples e múltipla, logarítmico, exponencial, geométrico e função de potência. Todos os dados foram tratados pelos os softwares Mata nativa 2 e Bioestat 5.0. Registrou-se 32 espécies em 11 famílias que apresentaram um índice de riqueza de táxon de 4,86 e a diversidade de Shannon 2,71. Valores considerados elevados quando comparados com trabalhos realizados em outras fisionomias de caatinga. Os parâmetros de estrutura apresentaram valores baixos, densidade (2.395 planta/ha-1), área basal (6,69 m2/ha-1), altura e diâmetro médios (3,52 m e 8,67 cm), área da copa (5.872 m2 ha-1) e biomassa (16,3 Kg ha-1). As espécies dominantes foram do estrato arbustivo, confirmando-se que a vegetação dos Cariris Velhos apresenta uma fisionomia de espécimes com porte baixo e por se distribuírem de forma esparsa, considerase aberta, no entanto, sua diversidade é alta provavelmente por se tratar de uma área serrana, indicando que estas áreas são mais conservadas e assim desempenham função de zonas tampão para essas localidades. Após os testes de modelagem da equação de estoque de carbono, observou-se que a variável altura total (HT) quando avaliada isoladamente demonstrou baixos valores para o coeficiente de determinação R2, não sendo recomendada para estimar o estoque de carbono (EC). O DNS apresentou melhor correlação com o EC, porém, os valores obtidos para o coeficiente de determinação foram insuficientes, sendo possível explicar apenas 40% das variações. A combinação do DNS com a HT resultou em melhoria no valor do coeficiente. Os modelos que melhor se adequaram foram a função do tipo potência (EC= a DNS b) e a regressão linear simples e múltipla (EC = a + bX), no entanto, a baixa amostragem não permitiu formular uma equação, de maior precisão, que possibilitasse estimar o potencial de estoque de carbono em plantas da caatinga.
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A pol?tica de assentamentos rurais do INCRA no contexto do semi-?rido nordestino (1995-2002) / The land settlement policy of INCRA in the context of northeastern semi-arid regions

Monte, Francisco Clesson Dias 26 September 2006 (has links)
Made available in DSpace on 2016-04-28T20:12:50Z (GMT). No. of bitstreams: 1 2007-Francisco Clesson Dias Monte.pdf: 2303026 bytes, checksum: e41d695a7294159ead830a6aea848c4e (MD5) Previous issue date: 2006-09-26 / This current paper works on analysing the land settlement policies developed in the context of northeastern semi-arid regions under the responsibility of INCRA. It aims at having a critical reflection about the mentioned policy and making it clear that even if the experiences of settlement have important impact on the regions where they are located, its development in the semi-arid regions isn t supported by an attenuating strategic action of the restricted conditions of this type of climate. At first a reference chart is elaborated trying to show the development of the theme around the land policy and it s discussed its insertion in the political, economic and social conjuncture producing a new setting for the land reform in the country in the period of 1995-2002. Methodologically speaking, this dissertation is based on Klaus Frey s and Bol?var Lamounier s approaches and focuses on qualitative nature. It s hypothesized the idea that the universal nature in the conception of the policy and its excessive centralized management are the main causes for the low impact on the effective improvement for the families settled. In the first chapter, it s discussed the antagonisms and controversies about the economic, social and political viability of land settlement, the political fights of rural workers and their representative organization, the conceptions, organizations and resulting impacts. While the second chapter aims at showing the circumstances under which the settlements in the semi-arid regions are subjected and the critical aspects of the policy into practice, the third chapter shows the material results of the policies in the semiarid regions, commenting on considerations of qualitative nature. / Trata o presente trabalho da an?lise da pol?tica de assentamentos rurais desenvolvida no contexto da regi?o semi-?rida do Nordeste sob a responsabilidade do INCRA. Tem como objetivo fazer uma reflex?o cr?tica a respeito da citada pol?tica e tornar mais evidente que, no geral, mesmo que as experi?ncias dos assentamentos revelem impactos importantes nas regi?es onde os mesmos est?o localizados, o seu desenvolvimento no semi-?rido n?o est? sustentado por uma a??o estrat?gica mitigadora das condi??es restritas desse tipo clim?tico. Inicialmente, procuro construir um quadro de refer?ncia com o desenvolvimento da tem?tica em torno da pol?tica agr?ria e comento a sua inser??o na conjuntura pol?tica, econ?mica e social, formadora de um novo cen?rio para a reforma agr?ria no Pa?s, no qual, considero o per?odo de 1995-2002. Metodologicamente, o trabalho est? ancorado nas abordagens da Klaus Frey e de Bol?var Lamounier e tem como foco o car?ter qualitativo. Formulo como hip?tese, que o car?ter universalizado na concep??o da pol?tica e sua gest?o excessivamente centralizada, foram as causas preponderantes para o baixo impacto na melhoria efetiva das condi??es das fam?lias assentadas. No cap?tulo 1, procuro abordar os antagonismos e as controv?rsias em rela??o ? viabilidade econ?mica, social e pol?tica dos assentamentos rurais, a luta pol?tica dos trabalhadores rurais e de suas organiza??es representativas, as concep??es, as institucionalidades e os impactos resultantes. Procuro evidenciar no cap?tulo 2, os condicionantes a que est?o submetidos os assentamentos no semi-?rido e os pontos cr?ticos da execu??o da pol?tica, e, no cap?tulo 3, demonstrar os resultados materiais da pol?tica no semi?rido com considera??es de car?ter qualitativo.
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O repertório acústico de um especialista de rochedos da caatinga, o Mocó / The acoustic repertoire of a specialist of caatinga rockpiles, the rocky cavy

Raimundo Novaes Alencar Junior 19 January 2012 (has links)
A Caatinga é um ecossistema brasileiro análogo as savanas africanas apresentando escassez de chuvas e temperaturas altas. O mocó apresenta, importantes adaptações ao microambiente dos afloramentos rochosos. Esse roedor caviomorfo, abandonou o hábito pastador comum a outros roedores cavíneos, como preá e a capivara, pela capacidade de escalar árvores e se alimentar de folhas e frutos. Alongou o período de gestação e adotou o cuidado paterno. Interessados em entender de que forma a comunicação acústica teria se ajustado ao ambiente isolado dos rochedos da caatinga, gravamos e analisamos as emissões sonoras dos mocós. Foram 90 dias de trabalho de campo nas Fazendas Tamanduá e São Francisco, na cidade de Patos, Paraíba. Capturamos 13 animais (6 machos e 7 fêmeas) e fizemos registros em áudio e vídeo em três situações: 1) pareamentos em caixa teste, nas condições macho x macho, macho x fêmea e fêmea x fêmea, 2) animais em grupo em cativeiro, e 3) animais em vida livre. Encontramos um repertório de 11 sinais sonoros, registrados em 3 categorias amplas de comportamento: (1) Exploração/Forrageamento: Có de contato, Estalido, Chorinho e Drrr; (2) Alerta: Assobio de alarme, Drrr e Silvo; (3) Interação Agonística: Ganido, Grito, Ronco, Arfar, Assobio de alarme e o Baterdedentes. O repertório mostrouse mais rico do que o de outros caviomorfos, como o preá. Discutimos esse resultado em relação ao tipo de vida social da espécie em comparação com a de outros caviníneos e à vida nos rochedos da caatinga. Também sugerimos que o Assobio de alarme seja um comportamento compartilhado entre o mocó e outras espécies de roedores 10 de rochedos. Há uma perspectiva de continuidade da pesquisa em busca de uma maior compreensão da função biológica desse sinal e da riqueza desse repertório acústico / The environment of Brazilian Caatinga ecosystem is similar to African Savannah with low level of rain and high temperature. The Moco shows important adaptation at the microenvironment of rock outcrops. This caviomorph rodent abandoned grazing habit, commom at others Caviinae species such as the Cavy and the Capybara for the capacity of climbing trees feeding of leaves and fruits. It also lengthened the gestation period and adopted paternal care. Interested in understanding how acoustic communication would have adjusted to the isolated environment of Caatinga rock piles, we recorded and analyzed the signals songs of Moco. Past through 90 days in field at Fazenda Tamanduá and Sítio São Francisco located at Patos city Paraiba State in Brazil. We captured 13 animals (6 males and 7 females), acquired audio and video of animals in three different situations: 1) paired in tests boxes under conditions: male x male, female x male and female x female; 2) captivity group and 3) Living free. We found a repertoire with 11 acoustic signals registered in 3 broad behavioral categories: (1) Exploration/ Foraging: Contact call, Co, Clicking (Estalido), Whine (Chorinho) and Drrr call, (2) Warning: Alarm whistle, Drrr call and Silvo, (3) Agonistic Interaction: yelp (Ganido), scream (Grito), grunt (Ronco), a breathless like sound (Arfar), Alarm Whistle and ToothChatter. This repertoire showed more rich that other caviomorph as a cavy. eu escreveria esse parágrafo dessa forma: This repertoire seemed better than other caviomorph as a Cavy. We discussed those results comparing the social life of species with social life of others Caviinae and the life at the rock piles of Caatinga. We also suggested that the Alarm whistle is shared between the 12 Moco and others rock rodents. There is a perspective to continue this research looking for a better comprehension of the biologic function of this signal and acoustic repertoire richness
179

Bactérias associadas às cactáceas da Caatinga: promoção de crescimento de plantas sob estresse hídrico / Cacti-associated bacteria from Caatinga: plant growth promotion under water stress

Vanessa Nessner Kavamura 05 October 2012 (has links)
A Caatinga, bioma exclusivamente brasileiro, inserido no clima semiárido nordestino, apresenta xerófitas com alta resistência aos períodos de seca. Estas plantas associam-se a micro-organismos que também se encontram bem adaptados, desenvolvendo mecanismos de proteção celular contra o estresse hídrico, assim como proteção vegetal contra os efeitos negativos da dessecação. O presente estudo buscou compreender as bactérias associadas às cactáceas da Caatinga, analisando a estrutura das comunidades bacterianas de solo e da rizosfera de Cereus jamacaru durante a alteração do período chuvoso para o de seca, identificando os grupos dominantes e discutindo algumas funções que possibilitem a manutenção da interação solo-cacto-micro-organismo durante o período de seca. Além disso, buscou selecionar bactérias tolerantes à seca e que fossem capazes de promover crescimento de plantas sob estresse hídrico. Amostras foram coletadas ao longo da Caatinga, em cinco estados: BA, CE, PI, PB e RN totalizando cinco pontos. Com o uso de metodologias independentes de cultivo, foi possível observar que o período de amostragem (chuvoso/seca) foi o principal responsável pela alteração na estrutura das comunidades bacterianas. Os filos Proteobacteria e Bacteroidetes foram abundantes durante o período chuvoso e os filos Actinobacteria e o gênero Bacillus abundantes durante o período de seca. Com o uso de metodologias dependentes de cultivo, foram isoladas com bastante frequência linhagens pertencentes ao gênero Bacillus, capazes de crescer em meio com reduzida atividade de água e com alguns mecanismos de proteção contra a dessecação, como a produção de exopolissacarídeos e biofilme. Além disso, várias linhagens apresentaram mecanismos de promoção de crescimento de plantas diretos e/ou indiretos, como produção de fitohormônio, disponibilização de P por meio de solubilização, fixação de nitrogênio, redução dos efeitos negativos do estresse causados por etileno, produção de celulase e amônia. Uma linhagem de Bacillus sp. foi capaz de promover crescimento de milho sob estresse hídrico, incrementando alguns parâmetros vegetais analisados. São discutidos o uso de consórcio bacteriano entre duas linhagens, além dos mecanismos que os micro-organismos dispõem para tolerar condições ambientais adversas e ainda as funções que estes micro-organismos podem ter na proteção vegetal contra a dessecação. / Caatinga, a Brazilian unique biome, inserted in the semi-arid climate of Brazilian northeast, presents xerophytes with high resistance to drought periods. These plants are found in association with well-adapted microorganisms that have evolved some cellular protection mechanisms against water stress, as well as plant protection against the negative effects of desiccation. This work aimed to study the bacteria associated to some Caatinga cacti, with respect to the structure of bacterial communities of bulk soil and rhizosphere of Cereus jamacaru during the modification of rainy season to dry season, identifying the dominant groups and discussing some functions that enable the soil-cactus-microorganism interaction maintenance during drought. Besides, we searched for drought-tolerant bacteria able to promote plant growth under water stress. Samples were collected along the Caatinga biome in five states: BA, CE, PI, PB, and RN in a total of five points. With unculturable techniques, it was possible to observe that the sampling season (rainy/dry) was the main driver for the modification of bacterial communities\' structure. Proteobacteria and Bacteroidetes phyla were the most abundant during the rainy season while phylum Actinobacteria and Bacillus group were the most abundant during the dry season. With culturable techniques, it was observed a high frequency of strains belonging to genus Bacillus that were able to grow in medium at reduced water activity and displaying some mechanisms of desiccation protection such as the production of exopolysaccharides and biofilm. Furthermore, several strains showed mechanisms of direct and/or indirect plant growth promotion, like the production of fitohormone, availability of P through solubilization, nitrogen fixation, reduction of negative effects caused by stress-induced ethylene, production of cellulase and ammonia. One strain of Bacillus sp. was able to promote maize growth under water stress, increasing some of the analyzed plant parameters. The use of bacterial consortium between two strains, as well as mechanisms displayed by microorganisms under adverse environmental conditions and their functions in plant protection against desiccation are also discussed.
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Towards applied modeling of the human-eco-system an approach of hydrology based integrated modeling of a semi-arid sub-catchment in rural north-west India

Jackisch, Conrad January 2007 (has links)
The development of rural areas concerning food security, sustainability and social-economic stability is key issue to the globalized community. Regarding the current state of climatic change, especially semi-arid regions in uenced by monsoon or El Niño are prone to extreme weather events. Droughts, ooding, erosion, degradation of soils and water quality and deserti cation are some of the common impacts. State of the art in hydrologic environmental modeling is generally operating under a reductionist paradigm (Sivapalan 2005). Even an enormous quantity of process-oriented models exists, we fail in due reproduction of complexly interacting processes in their effective scale in the space-time-continuum, as they are described through deterministic small-scale process theories (e.g. Beven 2002). Yet large amounts of parameters - with partly doubtful physical expression - and input data are needed. In contradiction to that most soft information about patterns and organizing principles cannot be employed (Seibert and McDonnell 2002). For an analysis of possible strategies on the one hand towards integrated hydrologic modeling as decision support and on the other hand for sustainable land use development the 512 km2 large catchment of the Mod river in Jhabua, Madhya Pradesh, India has been chosen. It is characterized by a setting of common problems of peripheral rural semi-arid human-eco-systems with intensive agriculture, deforestation, droughts and general hardship for the people. Scarce data and missing gauges are adding to the requirements of data acquisition and process description. The study at hand presents a methodical framework to combine eld scale data analysis and remote sensing for the setup of a database focusing plausibility over strict data accuracy. The catena-based hydrologic model WASA (Güntner 2002) employes this database. It is expanded by a routine for crop development simulation after the de Wit approach (e.g. in Bouman et al. 1996). For its application as decision support system an agentbased land use algorithm is developed which decides on base of site speci cations and certain constraints (like maximum pro t or best local adaptation) about the cropping. The new model is employed to analyze (some) land use strategies. Not anticipated and a priori de ned scenarios will account for the realization of the model but the interactions within the system. This study points out possible approaches to enhance the situation in the catchment. It also approaches central questions of ways towards due integrated hydrological modeling on catchment scale for ungauged conditions and to overcome current paradigms. / Die Entwicklung ländlicher Regionen hinsichtlich von Ernährungssicherheit, Nachhaltigkeit und sozio-ökonomischer Stabilität ist eine der wichtigsten Aufgaben unserer globalisierten Gemeinschaft. In Hinblick auf den Klimawandel sind insbesondere semi-aride Gebiete im Einfluss von Monsun oder El Niño von extremen Wetterereignissen betroffen. Tockenheiten, Überschwemmungen, Erosion, Bodendegradation, Verschlechterung der Wasserqualität und Versteppung sind nur einige, oft beobachtete Folgen. Der Stand der Forschung in Sachen hydrologischer Umweltmodellierung ist insbesondere einem reduktionistischen Paradigma verhaftet (Sivapalan 2005). Obwohl eine enorme Menge verschiedenster Prozessmodelle existiert können auf Grundlage kleinskaliger Prozessapproximationen die komplex interagierenden Prozesse in ihren wirkenden Skalen im Raum-Zeit-Kontinuum nur begrenzt beschreiben werden (z.B. Beven 2002). Während die verwendeten Modelle große Mengen an Parametern und Daten benötigen, können wichtige Informationen über Muster und Organisationsprinzipien nicht in die Simulationen einfließen. Für eine Analyse möglicher Wege und Restriktionen der integrierten hydrologischen Modellierung als Mittel in der Entscheidungsunterstützung wurde das 512 km² große Einzugsgebiet des Mod Flusses in Jhabua, Madhya Pradesh, Indien ausgewählt. Es ist gekennzeichnet von charakteristischen Problemen der Neuen Peripherie (z.B. Scholz 2004) (im human-geographischen Kontext) und intensiv anthropogen beeinflusster Agrar-Öko-Systeme der semi-ariden Tropen. Die dünne Datengrundlage des nicht-bepegelten Einzugsgebiets stellt dabei eine besondere Anforderung an die Datenakquise. In der vorliegenden Arbeit wird ein methodischer Ansatz vorgestellt, der Feld- und Fernerkundungstechniken zur Landschaftsanalyse verbindet. Mit dem Fokus auf Plausibilität statt strenger "Datengenauigkeit" wird eine Datenbank zur hydrologischen Modellierung des Gebiets entwickelt. Das Catena-basierte hydrologische Prozessmodell WASA (Güntner 2002) wird um eine Routine zur Simulation der Entwicklung von Nutzpflanzen nach de Wit (z.B. in Bouman et al. 1996) erweitert. Zur Anwendung des Modells als Entscheidungsunterstützungssystem ist ein agentenbasierter Landnutzungsalgorithmus entwickelt worden, welcher auf Grundlage von Standorteigenschaften und politischen Vorgaben wie Profitmaximierung oder Standortanpassung über die Landnutzung entscheidet. Das neue Modellsystem wird zur Untersuchung von einigen Landnutzungstrategien so verwendet, dass nicht antizipierte Szenarien sondern die Wechselwirkung des Systems selbst die Realisation des Modells bestimmen. Die Umsetzung zeigt einerseits mögliche Ansätze zur Verbesserung der Situation im Untersuchungsgebiet auf. Anderseits gibt sie konkrete Vorschläge zu zentralen Fragen hydrologischer Umweltmodellierung und zur Überwindung bestehender Paradigmen.

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