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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 de ?reas degradadas pela extra??o de cascalho: substrato, estrutura horizontal e flor?stica da regenera??o natural

Lage, Mayara Ribeiro 21 October 2016 (has links)
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-06-09T18:42:59Z No. of bitstreams: 2 mayara_ribeiro_lage.pdf: 7630209 bytes, checksum: fb39ab87647bdca7bc30286669fad378 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-06-22T14:54:33Z (GMT) No. of bitstreams: 2 mayara_ribeiro_lage.pdf: 7630209 bytes, checksum: fb39ab87647bdca7bc30286669fad378 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-06-22T14:54:33Z (GMT). No. of bitstreams: 2 mayara_ribeiro_lage.pdf: 7630209 bytes, checksum: fb39ab87647bdca7bc30286669fad378 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Um trecho da BR- 367, que liga a cidade de Diamantina ao distrito de Guinda, em Minas Gerais, perpassa por ?reas de campo rupestre na Serra do Espinha?o Meridional e apresenta diversas ?reas de empr?stimo, constitu?das por jazidas de material granular consumidas em obra rodovi?ria da pr?pria via entre as d?cadas de 1960 e 1980. Atualmente tais ?reas ainda apresentam-se fortemente degradadas, caracterizando-se pela fraca cobertura vegetal, exposi??o do solo e inexist?ncia de um sistema de drenagem superficial eficiente. Neste contexto, surge a necessidade de alternativas que tenham efic?cia na integra??o dos conhecimentos silviculturais e princ?pios ecol?gicos visando o retorno destas ?reas ?s condi??es pr?ximas das originais. Este trabalho teve como objetivo entender a rela??o entre vari?veis ambientais e a estrutura horizontal e flor?stica das esp?cies colonizadoras destes ambientes degradados. Foram selecionadas quatro ?reas degradadas, analisadas por fotografias a?reas referentes aos anos de 1960 e 1979 nas quais foi poss?vel detectar das ?reas degradadas pontuais. Para o estudo do substrato estratificou-se as quatro ?reas selecionadas para a coleta de amostras deformadas e indeformadas de forma preferencial. Obteve-se as propor??es de areia, silte, argila, dados de resist?ncia ? penetra??o, densidade de part?culas e aparente, porosidade total, micro e macro porosidade. Para a an?lises qu?micas foram coletadas entre 5 subamostras de cada estrato com o intuito de se obter uma amostra composta do substrato superficial (0-20 cm), de forma a representar a heterogeneidade ambiental de cada ?rea. Foram analisados: pH em ?gua; teores de P, K+, Mg2+, Ca2+ e Al3+; complexo sortivo (acidez potencial (H+Al), satura??o e soma por bases (V% e SB), CTC (T), CTC efetiva (t) e satura??o por alum?nio (m%) e mat?ria org?nica (MO). Os dados obtidos foram aferidos e submetidos a an?lises estat?sticas. Realizou-se an?lise de componentes principais (PCA) pelo software PCORD vers?o 6, de modo a sintetizar as vari?veis de maior relev?ncia na correla??o das vari?veis analisadas. Para levantamento da comunidade vegetal foi empregado o m?todo da interse??o na linha no qual em cada ?rea foram alocadas doze linhas com 10,0 m de comprimento, distribu?das em zigzag, seguindo as coletas de solo, para correlacionar caracter?sticas do solo e vegeta??o. Cada linha foi subdividida em dez unidades amostrais (UA) cont?nuas, totalizando 470 UAs e anotado a ocorr?ncia de esp?cies de h?bito herb?ceo, arbustivo e arb?reo. Foram calculadoss par?metros fitossociol?gicos: frequ?ncia absoluta (FA), frequ?ncia relativa (FR), cobertura absoluta (CA), cobertura relativa (CR) e o valor de import?ncia (VI). Para comparar os diferentes setores das ?reas estudadas quanto ao perfil de estrat?gias ecol?gicas de esp?cies herb?ceas, estas foram classificadas em sistemas de guildas de acordo com as estrat?gias de regenera??o, estratifica??o e dispers?o. Nas quatro ?reas analisadas foram amostrados 1.517 indiv?duos, pertencentes a 22 fam?lias e 109 esp?cies. A an?lise dos atributos f?sicos e qu?micos do substrato evidenciou alta limita??o ao desenvolvimento de plantas colonizadoras, apresentando como restri??es a alta resist?ncia a penetra??o e substratos de textura arenosa com baixa fertilidade natural. Verificou-se que houve rela??o entre os gradientes ambientais e a abund?ncia e composi??o flor?stica da vegeta??o colonizadora, ficando a maioria das esp?cies mais fortemente correlacionada com as vari?veis MO, H+Al e V al?m de propor??o de Areia, PT, DMG e RP. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / A section of the BR-367, connecting the Diamantina town to the Guinda district, Minas Gerais, runs through areas of rupestrian field of Espinha?o Range and presents several loan areas, consisting of deposits of granular material consumed in road construction between the 1960?s and 1980?s, Currently, these areas are still heavily degraded, characterized by poor vegetation cover, soil exposure and the absence of an efficient surface drainage system. In this context, the need arises for alternatives that have effectiveness in the integration of silvicultural knowledge and ecological principles aiming the return of these areas to the conditions close to the originals. This work aimed to understand the relationship between environmental variables and the horizontal and floristic structure of the colonizing species of these degraded environments. Four degraded areas were selected, analyzed by aerial photographs referring to the years 1960 and 1979 in which it was possible to detect the degraded areas. For the study of the substrate, the four areas selected for the collection of deformed and undisturbed samples were stratified in a preferential way. The proportions of sand, silt, clay, penetration resistance data, particle and apparent density, total porosity, micro and macro porosity were obtained. For the chemical analyzes, 5 sub-samples of each stratum were collected with the aim of obtaining a composite sample of the surface substrate (0-20 cm), in order to represent the environmental heterogeneity of each area. The following parameters were analyzed: pH in water; Contents of P, K +, Mg2 +, Ca2 + and Al3 +; (S), saturation (V%), sum of bases (SB), CTC (T), effective CTC (t) and saturation by aluminum (m%) and organic matter. A PCA was performed by software PCORD version 6, in order to synthesize the variables of greater relevance in the correlation of the analyzed variables. Was used the method of the intersection in the line in which in each area were allocated twelve lines with 10.0 m in length, distributed in zigzag, following the soil collections, to correlate soil and vegetation characteristics. Each row was subdivided into ten continuous sample units (AU), totaling 470 POAs and the occurrence of species of herbaceous, shrub and arboreal habit. Phytosociological parameters were calculated: absolute frequency (AF), relative frequency (FR), absolute coverage (AC), relative coverage (CR), and importance value (VI). In order to compare the different sectors of the studied areas with respect to the profile of ecological strategies of herbaceous species, these were classified in guild systems according to the strategies of regeneration, stratification and dispersion. In the four areas analyzed, 1,517 individuals belonging to 22 families and 109 species were sampled. The analysis of the physical and chemical attributes of the substrate showed a high limitation to the development of colonizing plants, presenting as restrictions the high resistance to penetration and substrates of sandy texture with low natural fertility. It was verified that there was a relation between the environmental gradients and the abundance and floristic composition of the colonizing vegetation, being most of the species more strongly correlated with the variables MO, H+Al and V besides the proportion of Sand, PT, DMG and PR.

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