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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

Floresta atlântica do sul do Brasil : atividade e diversidade microbiológica do solo sob essências florestais leguminosas

Müller, Francihele Cardoso January 2016 (has links)
Orientador : Prof. Dr. Renato Marques / Coorientadores : profª. Drª. Fátima Maria de Souza Moreira, Prof. Dr. Emanuel Maltempi de Souza / Tese (doutorado) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Programa de Pós-Graduação em Engenharia Florestal. Defesa: Curitiba, 15/07/2016 / Inclui referências / Área de concentração : Conservação da Natureza / Resumo; A diversidade, a abundância e a dinâmica da microbiota do solo em florestas dependem, em grande parte, do processo de transformação da matéria orgânica do solo, cujas características dependem da vegetação florestal. Acredita-se que a presença de diferentes espécies florestais sobre o solo pode influenciar a BMS e a atividade microbiana; e entre outros, o processo de mineralização do N no solo. Os objetivos deste trabalho foram investigar as relações entre espécies arbóreas leguminosas (Andira anthelmia, Inga edulis, Inga striata, Pterocarpus rorhii) nativas da Floresta Atlântica do Sul do Brasil e parâmetros edáficos de natureza microbiológica. Avaliou-se C da biomassa microbiana (CBM) e N microbiano (Nmic), respiração basal do solo (RBS), quociente metabólico (qCO2) e a mineralização do nitrogênio; e caracterizou-se genotipicamente as comunidades microbianas do solo em áreas de regeneração natural em diferentes estágios sucessionais. A extração do CBM e Nmic foi realizada pelo método de irradiação-extração, a RBS por incubação das amostras com retenção de CO2 por NaOH e o qCO2 pela razão entre RBS e CBM; taxa de N mineralizado foi avaliada pelo método de incubação anaeróbica; e a diversidade de bactérias diazotróficas foi realizada pelo método de diluição seriada e cultivo em placa com os meios LGI, NFb e JNFb, purificação das colônias, amplificação e sequenciamento do 16S. Os resultados CBM e Nmic foram mais elevados no solo sob Inga edulis e Andira anthelmia; a RBS foi mais elevada no outono; qCO2 foi menor na primavera. Os valores de CBM e Nmic foram mais elevados no solo sob Inga edulis e Andira anthelmia; a RBS foi mais elevada no outono; qCO2 foi menor na primavera. Os valores de N mineralizado foram mais elevados nos solos sob I. edulis, assim como na camada superficial do solo e variaram conforme as estações do ano; indicando, assim, influência da espécies florestal, da profundidade de amostragem e das condições meteorológicas sobre a atividade microbiana. A caracterização genotípica mostrou que as bactérias encontradas pertencem aos filos Proteobacteria (90,4%), Firmicutes (4,8%) e Actinobacteria (4,8%). A maior diversidade de gêneros ocorreu nos solos sob A. anthelmia (14 gêneros); Burkholderia, Cupriavidus, Pseudomonas e Rhizobium foram mais frequentes, somando 37,5% da frequência total de gêneros; observou-se distinção das espécies florestais, com características como valores de pH, P, K, Ca e Mg agrupadas ao I. edulis; e, por fim, a distinção da floresta primária quanto as características químicas do solo. Assim, o estudo conclui que os fatores clima, espécies florestais e formação florestal podem influenciar o desenvolvimento e atividade microbiana do solo. Palavras-chave: Biomassa Microbiana do Solo, mineralização de N, bactérias diazotróficas, atividade microbiana e Fixação Biológica de Nitrogênio. / Abstract: The diversity, abundance and dynamics of soil microbiota in forests depends to a large extent on the process of transformation of soil organic matter, the characteristics of which depend on forest vegetation. It is believed that the presence of different forest species on the soil can influence BMS and microbial activity; and among others, the process of N mineralization in the soil. The objectives of this work were to investigate the relationships between tree species (Andira anthelmia, Inga edulis, Inga striata, Pterocarpus rorhii) native to the Atlantic Forest of southern Brazil and edaphic parameters of a microbiological nature. It was evaluated the carbon of the microbial biomass (CMB) and microbial nitrogen (Nmic), basal respiration of the soil (BRS), metabolic quotient (qCO2) and the mineralization of the nitrogen; and the microbial communities of the soil were characterized genotypically in areas of natural regeneration in different successional stages. The extraction of the CMB and Nmic was carried out by the irradiation-extraction method, the BRS by incubation of the samples with retention of CO2 by NaOH and the qCO2 by the ratio between BRS and CMB; mineralized N rate was evaluated by anaerobic incubation method; and the diversity of diazotrophic bacteria was performed by the serial dilution method and plaque culture with the LGI, NFb and JNFb media, colonization purification, 16S amplification and sequencing. The CMB and Nmic results were higher in the soil under Inga edulis and Andira anthelmia; BRS was highest in the fall; qCO2 was lower in spring. The values of mineralized N were higher in the soils under I. edulis, as well as in the superficial layer of the soil and they varied according to the seasons of the year; indicating, therefore, the influence of the forest species, the depth of sampling and the meteorological conditions on the microbial activity. The genotypic characterization showed that the bacteria found belong to the phyla Proteobacteria (90,4%), Firmicutes (4,8%) and Actinobacteria (4,8%). The greatest diversity of genera occurred in soils under A. anthelmia; Burkholderia, Cupriavidus, Pseudomonas and Rhizobium were more frequent, accounting for 37.5% of the total frequency; was observed the distinction between forest species, with characteristics such as pH, P, K, Ca and Mg values grouped with I. edulis; and, finally, the distinction of the primary forest as the chemical characteristics of the soil. Thus, the study concludes that the factors climate, forest species and forest formation may influence the development and microbial activity of the soil. Key-words: Soil Microbial Biomass, mineralization of N, diazrotrofic bacterial, microbial activity and Biological Nitrogen Fixation.
2

Avaliaçao das florestas de Araucaria angustifolia (Bert.)O. Ktze. do Sul do Brasil, através de imagens do satélite Landsat-II

Gantzel, Otto Luiz, 1948- 25 March 2011 (has links)
This research was carried out in the South of Brazil and had as its principal aim a qualitative and quantitative evaluations of the Araucaria angustifolia (Bert.) O. Ktze forests using Landsat imagery. Trough visual interpretation of monochromic images, Araucaria could always be identified by its 10w reflectance characteristic giving a dark tone wi.ch differentiated it from the surrounding forest. A methodology of analysis was developed using the technique of colour enhancement to define the types of forest and to separate the areas of Paraná Pine from the rest of the forested areas. Then diapositives were obtained from the television screen used in the 1-100 computer analysis system, showing different colour combinations wich enhanced certain analytical features. The analysis revealed that Araucaria absorbs a high level of solar energy giving a dark green characteristic wich differentiates it from other vegetation, principally deciduous forests. The following forest types were defined in the mapping; TYPE I - Araucaria angustifolia pure stands, with 80 to 100% density TYPE II - Araucaria angustifolia stands with 50 to 80% density TUPE III - Hardwood forests with a low density of Araucaria angustifolia TYPE IV - Plantations of Araucaria angustifolia TYPE V - Plantations of other species The areas in hectares of each of the Groups identified in the survey are as follows: Group Hectares Percentage I 120.776,56 0,76 II 444.642,20 2,79 III 2.353.307,86 14,78 IV 13.379,73 0,08 V 121.879,70 0,77 TOTAL 3.O53.985,90 19,18 The quantitative evaluation showed that 565,419ha of native forests of Araucaria angustifolia remain wich is 64% of the 1974 area and represents a deforestation rate of 79,294 hectares per year. The results of the study confirm that Landsat data can be sucessfuly used in forest surveys.

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