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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.
1

Caracteriza??o morfom?trica da sub-bacia do Ribeir?o Cachimbal, RJ e atributos ed?ficos condicionantes no processo erosivo em pedoformas c?ncava e convexa / Morphometric characterization of the sub-basin of Ribeir?o Cachimbal, RJ and edaphic conditioners attributes of the erosion process on concave and convex landforms

GOMES, Jo?o Henrique Gaia 23 February 2017 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-08-17T17:49:24Z No. of bitstreams: 1 2017 - Jo?o Henrique Gaia Gomes.pdf: 3515689 bytes, checksum: 6a7151f0e574d679527cd2a45c6c5668 (MD5) / Made available in DSpace on 2017-08-17T17:49:24Z (GMT). No. of bitstreams: 1 2017 - Jo?o Henrique Gaia Gomes.pdf: 3515689 bytes, checksum: 6a7151f0e574d679527cd2a45c6c5668 (MD5) Previous issue date: 2017-02-23 / CAPES / As a result of activities such as agriculture, pastures for cattle raising, mining areas, logging and improper occupation in urban areas, about 28% of the Brazilian territory is classified as degraded. In some regions of Brazil, due to their geomorphological aspects associated to the intense precipitations that occur in summer, degradation problems such as erosive processes and slope slides can be verified. The Pinheiral-RJ region currently has only 18% of its territory under native forest cover at different levels of alteration and regeneration, with 88% of its area classified as high or very high vulnerable to erosion. Therefore, the objective of this work was to evaluate the effect of soil attributes and morphology of the sub-basin of the CachimbalRiver as conditions to the erosive process in different topographic features (pedoforms), concave and convex, in the Middle Vale do Para?ba do Sul -RJ, in order to generate information that contributes to the recovery programs of degraded areas. The digital elevation model (DEM) was generated using topographic maps of the municipalities of Volta Redonda (Page SF-23-Z-A-V-2) and Pira? (Page SF-23-Z-VI-1) using ArcGis 10.2 software. The quantification of gull numbers was performed through Google Earth. Morphometric characterization, trench opening for soil classification, collection of soil samples, physical and routine fertility analysis and analysis of soil attributes variability were performed based on literature criteria. It was verified that there is no susceptibility to flood in the studied area due to its elongated shape. The sub-basin has a dendritic drainage pattern, flow order of 5th degree, and very large drainage density(Dd). In particular, the average hydrographic density (Hd) value indicates a high potential for generating new channels. Although roughness coefficient (Cr)indicates agricultural capacity for agriculture, roughness index (Ir) demonstrates the need to adopt more nuanced agricultural practices that take into account the particular characteristics of the area and recognize variations in the terrain and soil characteristics. 30 gullies were quantified throughout the sub-basin, 24 being in the convex pedoform and 6 in the concave. The physical and chemical attributes differ in the environments. / Em decorr?ncia de atividades como agricultura, pastagens destinadas a pecu?ria, ?reas de minera??o, explora??o madeireira e ocupa??o impr?pria nas regi?es urbanas, cerca de 28% do territ?rio brasileiro ? classificado como degradado. Em algumas regi?es do Brasil, em fun??o dos seus aspectos geomorfol?gicos associados ?s intensas precipita??es ocorridas no ver?o, s?o verificados problemas de degrada??o como processos erosivos e deslizamentos de encostas. A regi?o de Pinheiral-RJ apresenta atualmente, apenas 18 % de seu territ?rio sob cobertura florestal nativa em diferentes n?veis de altera??o e regenera??o, possui88% de sua ?rea classificada como alta ou muito alta vulnerabilidade ? eros?o. Sendo assim, o objetivo desse trabalho foi avaliar o efeito dos atributos do solo e da morfologia da sub-bacia do ribeir?o Cachimbal como condicionantes no processo erosivo em diferentes fei??es topogr?ficas (pedoformas), c?ncava e convexa, na Regi?o do M?dio Vale do Para?ba do Sul-RJ, com finalidade de gerar informa??es que contribuam para os programas de recupera??o de ?reas degradadas. Foi gerado o modelo digital de eleva??o (MDE)atrav?s das cartas topogr?ficas dos munic?pios de Volta Redonda (Folha SF-23-Z-A-V-2) e Pira? (Folha SF- 23-Z-VI-1), utilizando o software ArcGis 10.2. A quantifica??o do n?mero de vo?orocas foi realizada atrav?s do Google Earth. A caracteriza??o morfom?trica, a abertura de trincheiras para classifica??o do solo, a coleta das amostras de terra, as an?lises f?sicas e de rotina da fertilidade e a an?lise da variabilidade dos atributos do solo foram realizadas baseando-se em crit?rios da literatura. Verificou-se que n?o h? susceptibilidade de enchente na ?rea estudada, devido a sua forma alongada. A sub-bacia tem um padr?o de drenagem dendr?tico, ordem de fluxo de 5? grau, e Densidade de drenagem (Dd) muito boa. Em particular, o valor da densidade de hidrogr?fica (Dh) indica um elevado potencial para gerar novos canais.Embora o Coeficiente de rugosidade (Cr) indique capacidade agr?cola para a agricultura, o ?ndice de rugosidade (Ir) demonstra a necessidade de adotar pr?ticas agr?colas mais nuan?adas que levem em conta as caracter?sticas particulares da ?rea e que reconhe?am varia??es no terreno e caracter?sticas do solo. Foram quantificadas 30 vo?orocas em toda a sub-bacia, sendo 24 na pedoforma convexa e 6 na c?ncava. Os atributos f?sicos e qu?micos diferiram quanto aos ambientes.
2

An?lise flor?stico-estrutural, rela??o vegeta??o-ambiente e transi??o floresta-campo das matas de galeria do Parque Nacional das Sempre-Vivas (PNSV), MG / Floristic-structural analysis, vegetation-environment relationship, and forest-field transition from gallery forests of the Sempre-Vivas National Park (PNSV), MG

Costa, Tha?s Ribeiro 02 August 2017 (has links)
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-07-06T13:25:22Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) thais_ribeiro_costa.pdf: 3235496 bytes, checksum: 6f8cdc08809043df5efea75372782e92 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-07-18T13:13:10Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) thais_ribeiro_costa.pdf: 3235496 bytes, checksum: 6f8cdc08809043df5efea75372782e92 (MD5) / Made available in DSpace on 2018-07-18T13:13:10Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) thais_ribeiro_costa.pdf: 3235496 bytes, checksum: 6f8cdc08809043df5efea75372782e92 (MD5) Previous issue date: 2017 / Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Este estudo teve como objetivo conhecer a composi??o flor?stica da comunidade arb?rea e sua rela??o com o ambiente, bem como avaliar a diversidade, estrutura e as fun??es ecol?gicas das esp?cies de dezoito fragmentos de mata de galeria inund?vel. Al?m disso, se prop?s a caracterizar a vegeta??o da matriz de entorno de nove fragmentos de mata e galeria, bem como verificar se vari?veis ambientais atuam na transi??o entre as duas fitofisionomias, com ?nfase nas propriedades qu?micas do solo. O estudo foi conduzido no Parque Nacional das Sempre-Vivas, na Serra do Espinha?o, Minas Gerais. Foram inventariadas 5% da ?rea total de cada fragmento, instalando-se parcelas permanentes de 100 m? (totalizando 0,72 ha de amostragem), onde foram amostrados todos os indiv?duos arb?reos com di?metro ? altura do peito igual ou superior a 5 cm (DAP ? 5 cm). Para amostragem da cobertura vegetacional da matriz de entorno, foi utilizado o m?todo dos pontos, totalizando 12 pontos por fragmento, distribu?dos nas dist?ncias de 10, 20 e 30 m no sentido borda-campo. Em cada parcela e em cada ponto, foi mensurada a umidade do solo e coletadas amostras de solo, para posteriores an?lises qu?micas. Para os fragmentos foram mensurados qualitivamente a cobertura do dossel, altura de crestamento e impactos ambientais. Foram amostrados 1265 indiv?duos arb?reos, distribu?dos em 76 esp?cies, 55 g?neros e 32 fam?lias. A comunidade em geral, apresentou valores de diversidade e equabilidade compativeis com outras matas de galeria inund?veis do pa?s. As esp?cies amostradas foram agrupadas em seis grupos funcionais distintos. A maioria dos fragmentos apresentou uma tend?ncia de est?gio seral mais avan?ado, com esp?cies predominantemente secund?rias iniciais e tardias, zooc?ricas, zoo?filas, densidade m?dia da madeira, sementes recalcitrantes e pl?ntulas do tipo faneroep?geo-foli?ceo. A distribui??o por classes diam?tricas dos indiv?duos da comunidade arb?rea e para as principais popula??es obteve uma tend?ncia de J-invertido, indicando bom potencial regenerativo. As vari?veis ambientais que se correlacionaram com a varia??o da composi??o de esp?cies foram ? disponibilidade de ?gua e condi??es de acidez. O baixo percentual de explica??o das vari?veis ambientais e espaciais ressaltam que as esp?cies nos fragmentos de mata de galeria distribuem-se de maneira estoc?stica. O fogo constituiu o impacto mais frequente no interior dos fragmentos, o que ressalta a necessidade de t?cnicas de manejo nessas ?reas. Os campos ?midos ao entorno dos fragmentos apresentaram-se com elevada cobertura de herb?ceas, mesmo ap?s o manejo do fogo. Para as caracter?sticas ed?ficas avaliadas observaram-se os maiores valores de umidade, pot?ssio, soma de bases, capacidade de troca cati?nica total e mat?ria org?nica nos solos sob floresta. Portanto, a defini??o dos limites entre as duas fitocenoses estudadas parece ser primariamente relacionada com o gradiente de fertilidade e umidade do solo. Permite-se aqui chamar a aten??o para a import?ncia de estudos de pequenos fragmentos vegetacionais para a amplia??o do conhecimento sobre a diversidade ambiental local e regional, e seus principais determinantes, e poss?veis consequ?ncias para a din?mica da vegeta??o dos ecossistemas. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / This study aimed to know the floristic composition of the tree community and its relationship with the environment, as well as to evaluate the diversity, structure and ecological functions of the species of eighteen fragments of forest of flooded gallery. In addition, it was proposed to characterize the vegetation of the surrounding matrix of nine forest fragments and gallery, as well as to verify if environmental variables act in the transition between the two phytophysiognomies, with emphasis on the chemical properties of the soil. The study was conducted in the Sempre-Vivas National Park, in the Serra do Espinha?o, Minas Gerais. 5% of the total area of each fragment were inventoried, and permanent plots of 100 m? (totaling 0.72 ha of sampling) were sampled, where all arboreal individuals with a breast height diameter equal to or greater than 5 cm were sampled (DAP ? 5 cm). In order to sample the vegetative cover of the environment matrix, the points method was used, totaling 12 points per fragment, distributed at distances of 10, 20 and 30 m in the edge-field direction. In each plot and at each point, soil moisture was measured and soil samples were collected for further chemical analysis. For the fragments, the canopy cover, height of crust and environmental impacts were measured. A total of 1265 arboreal individuals were sampled, distributed in 76 species, 55 genera and 32 families. The community in general presented values of diversity and equability compatible with other floodplain gallery forests in the country. The species sampled were grouped into six distinct functional groups. Most of the fragments presented a trend of more advanced seral stage, with predominantly early and late secondary species, zoocoric, zoo-philological, mean wood density, recalcitrant seeds, and phaneroege-foliaceous-type seedlings. The distribution by diameter classes of the individuals of the tree community and for the main populations obtained a tendency of J-inverted, indicating good regenerative potential. The environmental variables that correlated with the variation of the species composition were the availability of water and acidity conditions. The low percentage of explanation of the environmental and spatial variables emphasize that the species in the fragments of gallery forest distribute stochastic way. Fire was the most frequent impact within the fragments, which highlights the need for management techniques in these areas. The wetlands surrounding the fragments presented high herbaceous cover, even after fire management. The highest values of moisture, potassium, sum of bases, total cation exchange capacity and organic matter in soils under forest were observed for edaphic characteristics evaluated. Therefore, the definition of the boundaries between the two phytochenoses studied seems to be primarily related to the fertility and soil moisture gradients. It is worth noting here the importance of studies of small vegetation fragments to increase knowledge about local and regional environmental diversity and their main determinants and possible consequences for the dynamics of ecosystem vegetation.

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