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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.
51

Florística, estrutura e mapeamento da vegetação de caatinga da Estação Ecológica de Aiuaba, Ceará / Floristics, structure and mapping of caatinga vegetation of Aiuaba Ecological Station, Ceará state

Jesus Rodrigues Lemos 30 March 2006 (has links)
A caatinga foi reconhecida recentemente como uma das 37 grandes regiões naturais do planeta. De um modo geral, tem sido descrita na literatura como pobre, possuindo baixo valor para fins de conservação. Talvez devido a este fato, a caatinga seja o bioma brasileiro mais desvalorizado e menos conhecido botanicamente, permanecendo como um dos mais desconhecidos na América do Sul do ponto de vista científico. Neste contexto, é preemente a necessidade da ampliação do conhecimento sobre a distribuição de organismos e a forma como eles estão organizados em comunidades na caatinga. No Estado do Ceará, a caatinga é a unidade fito-ecológica mais representativa espacialmente, abrangendo aproximadamente 72.980 Km2 e apesar da grande abrangência espacial da caatinga, pouco se conhece ainda sobre seus padrões de comunidades vegetais no Estado. Assim, este trabalho objetivou contribuir com a ampliação do conhecimento sobre a caatinga, investigando a flora e estrutura, bem como realizando o mapeamento orbital das fisionomias existentes na vegetação da Estação Ecológica (EE) de Aiuaba, Ceará. Esta é uma área considerada, pelo Programa Nacional da Biodiversidade/PROBIO, de Alta Importância Biológica no estado do Ceará. Foram realizadas coletas botânicas mensais, aleatórias, no período de outubro/2003 a fevereiro/2005, de ervas, subarbustos, arbustos, árvores, epífitas e lianas. A coleção botânica encontra-se depositada no acervo dos Herbários SPF, EAC, HUVA, IPA e K. No levantamento florístico foram coletados 183 espécimes, pertencentes a 47 famílias, 113 gêneros e 161 espécies. Deste total, dois táxons estão sendo propostos como espécies novas para a ciência. As famílias mais ricas em termos específicos foram Leguminosae, Euphorbiaceae, Bignoniaceae, Convolvulaceae, Acanthaceae e Asteraceae, as quais responderam por 51,5% do total das espécies. O maior índice de similaridade de Sørensen (IS) verificado entre a área de estudo e outros levantamentos realizados em diferentes estados do Nordeste brasileiro foi de 23,33%. Algumas espécies registradas na EE apresentam distribuição em todo o semi-árido nordestino, com algumas ocorrendo em outros estados brasileiros e até em outros países da América do Sul. Para o estudo fitossociológico, foram alocadas através de sorteio, 50 parcelas de 10 x 10 m em uma área de 1,5 ha. Foram medidos os caules de todos os indivíduos lenhosos vivos ou mortos ainda em \"pé\", inclusive cipós, que se individualizassem ao nível do solo e que atendessem aos seguintes critérios: Diâmetro ao Nível do Solo (DNS) >= 3 cm e altura total (AT) >= 1 m. Foram amostrados 3.007 indivíduos distribuídos em 47 espécies e 21 famílias. Leguminosae, Euphorbiaceae, Erythroxylaceae, Acanthaceae, Bignoniaceae e Rutaceae responderam por 65,9% das espécies e as três primeiras totalizaram 62,97% do valor de importância total. Croton floribundus (Euphorbiaceae), Piptadenia moniliformis (Leg. Mimosoideae), Erythroxylum caatingae (Erythroxylaceae) e Bauhinia cheilantha (Leg. Caesalpinioideae) tiveram os maiores valores de importância. As alturas e os diâmetros médios e máximos foram 4,51 e 13 m e 7,28 e 44,88 cm, constatando-se tratar de um trecho de caatinga cuja maioria dos indivíduos concentra-se no estrato inferior a 5 m de altura, com algumas espécies emergentes. O uso de imagens CBERS-2 e dados de campo proporcionaram a elaboração de um mapa da vegetação da EE de Aiuaba. Através de processamento de imagens, utilizando o Normal Difference Vegetation Índex (NDVI), foi produzido um mapa vegetacional. Foram diagnosticadas três fisionomias vegetacionais, havendo predomínio de caatinga arbustiva-arbórea alta aberta. A importância deste estudo está nas informações básicas acerca do estado atual da vegetação, vindo a fornecer subsídio para estudos futuros relacionados à compreensão e previsão de mudanças no padrão de distribuição das comunidades vegetais, bem como possibilitar a efetivação de investigações mais detalhadas. No aspecto geral, este estudo gerou informações acerca da diversidade biológica e ambiental da EE de Aiuaba. Informações como estas são fundamentais para o entendimento da evolução, da ecologia e da conservação de uma biota, vindo a fornecer suporte às decisões governamentais nas áreas de proteção ambiental, bem como no manejo das mesmas / Caatinga was recently recognized as one of the 37 great natural regions of the planet. In general, it has been described in literature as poor, having little value for conservation purposes. Perhaps due to this fact, caatinga may be the most devalued and least botanically recognized Brazilian biome, remaining as one of the most unknown in South America from a scientific point of view. In this context, the need for broadening knowledge about the distribution of organisms and the way they are organized into communities in caatinga is predominant. In the state of Ceará, caatinga is the most spatially representative phyto-ecological unit, covering approximately 72,980 Km2 and despite the great spatial coverage of caatinga, little is yet known about its patterns of vegetal communities in the State. Therefore, this study aims to contribute to the broadening of knowledge about caatinga, investigating the flora and structure, as well as carrying out the orbital mapping of the existing physiognomies in the vegetation of the Estação Ecológica (EE) in Aiuaba, Ceará state. This is an area considered, by the National Biodiversity Program/PROBIO, to be of High Biological Importance in the state of Ceará. Random monthly botanical collections were carried out, in the period from October/2003 to February/2005, of herbs, subshrubs, shrubs, trees, epiphytes and lianas. The botanic collection is to be found deposited in the SPF, EAC, HUVA, IPA and K Herbarium collections. In the floristic survey 183 specimens were collected, belonging to 47 families, 113 genera and 161 species. From this total, two taxa are being proposed as new species for science. The richest families in specific terms were Leguminosae, Euphorbiaceae, Bignoniaceae, Convolvulaceae, Acanthaceae and Asteraceae, which corresponded to 51.5% of the species total. The highest Sørensen\'s Similarity Index (IS) rate verified between the study area and other surveys carried out in different states of the Brazilian Northeast was 23.33%. Some species registered in the EE present a distribution throughout the northeastern semi-arid area, with some occurring in other Brazilian states and even in other South American countries. For the phyto-sociological study, 50 plots of 10 x 10m in an area of 1.5ha were assigned, by means of a draw. The stems of all living or dead but still \"standing\" woody organisms were measured, including lianas, which might become distinct at ground level and which might observe the following criteria: Diameter at Ground Level (DNS) >= 3cm and Total Height (AT) >= 1m. Three thousand and seven organisms were sampled distributed into 47 species and 21 families. Leguminosae, Euphorbiaceae, Erythroxylaceae, Acanthaceae, Bignoniaceae and Rutaceae corresponded to 65.9% of the species and the first three totaled 62.97% of the total importance value. Croton floribundus (Euphorbiaceae), Piptadenia moniliformis (Leg. Mimosoideae), Erythroxylum caatingae (Erythroxylaceae) and Bauhinia cheilantha (Leg. Caesalpinioideae) had the greatest importance values. The average and maximum heights and diameters were 4.51 and 13m and 7.28 and 44.88cm, proving that deals with a stretch of caatinga where the majority of organisms are concentrated in the stratum of less than 5m in height, with some emergent species. The use of CBERS-2 images and field data provided the elaboration of a vegetation map at the EE in Aiuaba. Through the processing of images, using the Normal Difference Vegetation Index (NDVI), a vegetation map was produced. Three vegetational physiognomies were diagnosed, with a predominance of tall open shrubby-arboreal scrub. The importance of this study is in the basic information regarding the current state of vegetation, providing assistance for future studies related to the understanding and forecast of changes in the distribution pattern of vegetal communities, as well as enabling the effectuation of more detailed investigations. In a general aspect, this study generated information about the biological and environmental diversity of the EE in Aiuaba. Information like this is fundamental for the understanding of evolution, ecology and the conservation of a biota, providing support for governmental decisions in areas of environmental protection, as well as in the management of them
52

Flowering plants of Omega Mine, Table Mountain, Tuolumne County, California

Wilcox, Mary 01 January 1974 (has links) (PDF)
The flora of California has been studied as a whole, but with the exception of Yosemite Valley few specific areas in Tuolumne County have been investigated. The area chosen for this investigation was approximately forty acres of the lava flow known as Table Mountain. This forty acres is located in the southeast portion of the Omega Mine near Rawhide Flat, Tuolumne County, California. The decision to use this area for study was based on its relative freedom from man's influence and its accessibility. The Omega Vine belongs to the author and its use was restricted during the period of investigation
53

<em>Vitis</em> Seeds (Vitaceae) from the Late Neogene Gray Fossil Site, Northeastern Tennessee, USA.

Gong, Fade 19 December 2009 (has links) (PDF)
This study focuses on the morphometric and systematic studies of fossil vitaceous seeds recently recovered from the Gray Fossil Site (7-4.5 Ma, latest Miocene-earliest Pliocene) northeastern Tennessee. Morphologically, all fossil seeds correspond to the extant subgenus Vitis (genus Vitis) of the Vitaceae based on the smooth dorsal surface with a centrally positioned chalaza connected with a conspicuous chalaza-apex groove and short linear ventral infolds that are slightly diverged apically. A multivariate analysis based on 11 measured characters from 76 complete seeds identified three types of seeds, each representing a distinct morphotaxon. Based on comparison with modern and fossil vitaceous specimens, three new species were recognized: Vitis grayana sp. nov., Vitis lanatoides sp. nov., and Vitis latisulcata sp.nov. The close resemblance between the first two fossil grapes (Vitis grayana and Vitis lanatoides) with extant eastern Asian Vitis provides further evidence that the eastern Asian floristic elements existing in the southeastern North American flora continued to as late as late Neogene.
54

Phytogeographic study of the Kaokoveld Centre of Endemism

Craven, Patricia 03 1900 (has links)
PhD / Thesis (PhD (Botany and Zoology))—University of Stellenbosch, 2009. / An intriguing biogeographic area that lies in northwestern Namibia and southwest Angola is known for having numerous endemic taxa. It had, however remained vaguely defined because of the complex flora, the arid environment and confusing and inconsistent use of biogeographic terminology. This thesis redefined the area as a centre of endemism based on recurrent patterns of plant distributions by shared species. The end result is a well-defined entity with regard to, not only geographic boundaries and floristic elements, but also to its history and floristic relationships. A vast amount of information on the plants of the area, their affinities and their distributions is required for a study of this nature and this was undertaken through literature surveys and field work. All the relevant information on Namibia and the southwestern Angolan flora, i.e. the region and the study area, were incorporated into a database which formed the bases for numerical analysis and GIS studies. The database also brought together a wide range of information from literature sources that included facts and theories about the past and present physical environment. The structure of the database permitted querying this electronic data in many different ways. To accommodate the wide variety of subjects in a logical way, the thesis was divided into two sections. Section A concentrated on the region and provided background information and context. The theory, terminology and phytogeographic studies in the region were evaluated as a first step. A large amount and variety of palaeo-environmental and palaeo-ecological information, pertinent to the region was incorporated. Secondly the flora was assessed. Besides the diversity, distribution patterns of the plants within and outside the region, including disjunct distributions, phylogenies were assessment. Finally taxa with similar geographic ranges were grouped. These entities were mapped and both the taxa and their environments were evaluated Section B focused on the core area, namely the Kaokoveld Centre of Endemism, which was delimited by numerical techniques, and then investigated further with regard to its floristic components, relationships and origins. The flora and endemic components are described in detail. The result is a well-defined centre of endemism which comprises one endemic family, 10 endemic genera and nearly 300 endemic species. The flora of the Centre includes about 1600 species in nearly 550 genera in 130 families. Three floristic Groups, identified in section A, that have a remarkable number of endemics are found in the Centre. Historical explanations for the distribution patterns were suggested and the Group that includes Welwitschia mirabilis Hook.f., has been shown to be linked to the Arid Corridor. The demand for accurate knowledge about biodiversity has been highlighted by the Convention of Biological Diversity and there are a remarkable number of users with different requirements today. This study provides a much needed alternate look at the plants of the region, as well as a summation of the principle phytogeographic elements of the Namibian flora. It also includes a new phytogeographic classification and map of the floristic Groups of Namibia, which will contribute to defining floristic areas in the region.
55

Cape elements on high-altitude corridors and edaphic islands.

Carbutt, Clinton. 28 November 2013 (has links)
Common to the temperate floras throughout sub-Saharan Africa is a group of taxa with strong ties to the Cape Floristic Region (CFR) (≈ Cape elements). Their distribution is limited to the eastern escarpment of Africa (e.g. the Drakensberg Alpine Centre - DAC), on nutrient-rich humic soils, as well as on isolated sandstone outcrops of low elevation, on nutrient-poor soils (e.g. the Pondoland Centre - PC), suggesting that intrinsic soil fertility is not the primary determinant of their distribution. The principal aim of this study was to determine which aspect of the edaphic environment of the DAC is most influenced by temperature, that may indirectly render it nutrient-poor and therefore provide suitable niches for Cape elements, as in the PC. A multidisciplinary approach involving aspects of plant biogeography, plant ecology, plant ecophysiology and soil chemistry was therefore adopted. The study regions were the DAC, PC and the KwaZulu-Natal Midlands. The flora of the DAC was resurveyed for this study, and is richer than previously thought: 2818 native taxa, most of which (2520) are angiosperms. The phytogeography of the DAC and PC is discussed, and comparisons are made with the floras of KwaZulu-Natal and the CFR. Their climatic environments, as well as those for the CFR and Sneeuberge, were compared using rainfall and temperature data from a range of sources. These climatic regimes were correlated with the floristic patterns of Cape elements for the high-altitude regions of South Africa and Lesotho. Altitude and rainfall increased, and temperature decreased, as the number of Cape elements increased towards the DAC. This study provided a contemporary inventory of the Cape elements of the DAC and PC. A total of 89 genera are recognised as Cape elements, of which 60 (c. 67%) are shared between the two regions. The highest number of Cape elements recorded for the eastern escarpment was the DAC (72 genera), with the highest number from all sites analysed being the PC (77 genera). The most Cape elements are contributed by the Asteraceae, Scrophulariaceae, Iridaceae, Fabaceae, Orchidaceae and Restionaceae, partly due to the success of annual aerial parts and their geophytic growth forms, which are convergent in these families. Further compartmentalisation into life and growth forms shows that most Cape elements of the DAC and PC are either ericoid (and sclerophyllous) or mesic herbs and shrubs. The ecological and ecophysiological aspects of this study involved the use of reciprocal pot experiments established along a gradient of altitude from coastal hinterland to mountain, that investigated the interactions between altitude, temperature and substrate on plant productivity in sites known either to support or to exclude Cape elements. Three soils were used at each site, representative of the DAC, PC and KwaZulu-Natal Midlands. The interactions between 'soil' and 'site' (≈ the climatic environment) were quantified using a temperate test taxon (Diascia) that has a strong Cape-centred distribution. Plant characters relating to morphology and nutrient content, and soil characters relating to fertility, were used as the basis for comparing treatment effects (soil-site interactions). Soil nitrogen availability was assayed using pot experiments with Eragrostis curvula (Schrad.) Nees. Wheat pot experiments revealed no Al³⁺ toxicity in 'Drakensberg' soil. Non-metric multidimensional scaling (NMDS) and redundancy analysis (RDA) indicated that all soil-site interactions were significant contributors to biomass differences, and that the Cape taxon performed poorly in the nutrient-rich Drakensberg soil at low altitude. Soil samples indicated that Drakensberg soil was the most nutrient-rich, and Pondoland soil the most nutrient-poor. Although total nitrogen in Drakensberg soil was six times higher than Pondoland soil, both soils mineralised similar low levels of nitrogen at their respective spring temperatures. The result for Drakensberg soil (simulated so as to include the effect of altitude) meant that only 1.7% of its total nitrogen was mineralisable at 12°C (its mean spring temperature). These findings suggest that nitrogen mineralisation rate is a key growth-limiting factor in the DAC, exacerbated by a number of complex interactions with soil pH and organic matter. It is hypothesized that Cape elements are preadapted to high-altitude habitats. These habitats are nutrient-deprived due to low temperatures, which reduce metabolic rates and the movement of ions in cold soils. This constraint imposes nutrient-related stresses similar to those of the CFR and PC. Taxa that are adapted to the nutrient-poor soils of the CFR are preadapted to the temperature-induced 'nutrient-poor' soils of the DAC and vice versa. This 'compatibility' has allowed the reciprocal exchange of taxa between regions, as suggested by cladistic biogeographical analyses using Cliffortia, Disa, Moraea and Pterygodium. The strong overlap of Cape elements between the CFR and PC is a product of similar nutritional niches and ancient floristic continuity. The result therefore is a high number of Cape elements common to the DAC and PC. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2004.
56

ESTUDOS FITOGEOGRÁFICOS NA BACIA HIDROGRÁFICA DO ARROIO LAJEADO GRANDE OESTE DO RS / PHYTOGEOGRAPHICAL STUDIES IN THE BASIN HYDROGRAPHIC THE STREAM LAJEADO GRANDE - WEST OF THE RS

Alves, Fabiano da Silva 17 December 2008 (has links)
Phytogeographical studies that seek to understand how was the colonization and distribution of native vegetation in the territory do Rio Grande do Sul State, back since the end of the XIX century. However, currently, there is still no consensus with regard to different types shows that the vegetation in the state, nor about the terminology to be used more generally. When dealing specifically with the West and Southwest regions, the theme, "Phytogeography" is of utmost importance, therefore still has no points and clarified in the scientific literature. Facing this situation, the phytogeographical studies in the basin hydrographic the Lajeado Grande stream- west of the RS has as its main objective, to contribute to the advancement of knowledge phyto-geographic South Rio-Grandense. For that, initially, was made an analysis in terms of the physical environment, where they were recognized and differentiated, morpholithological units, based on the characteristics of the relief, of the substrate rocky and soils. These units were represented on the morpho-lithological map, which served as a geographical basis to achieve the floristic survey. Developed under the physiognomic and ecological aspect, this survey revealed the existence of different types in native vegetation. Since then, a study was conducted correlative between vegetation and physical environment in order to identify the factors that influence the environment in floristic composition and spatial distribution of vegetation cover. This correlation showed that all types, in the area under study, have close relations with the physical environment, presenting a "pattern" of geographic distribution. In certain situations, such relationships are so strong that two phanerophytas species were defined as "geo-indicators" of substrate rocky. The results in this study were represented in phyto-geographic map, defined from the types of vegetation in relation to the units morpho-lithological, and differentiated into: campos (grassland) in sandstone hills, campos with curupi (Sapium haematospermum Müll. Arg. Euphorbiaceae) in sandstone hills, campos with butiá-anão (Butia lallemantii Deble & Marchiori Arecaceae) in sandstone hills, campos in volcanic hills, campos with espinilhos (Acacia caven (Molina) Molina - Leguminosae ou Fabaceae) in volcanic hills, vegetation of cornijas (steps in middle rocky slopes), vegetation of morrotes (hills with slopes) of sandstone, capão (forest) of forest and the gallery forest. It is hoped that this work will serve as an allowance for future studies and proposals for conservation and preservation of biodiversity and natural landscapes in Rio Grande do Sul state. / Estudos fitogeográficos que buscam a compreensão de como ocorreu a colonização e a distribuição da vegetação nativa no território gaúcho, remontam desde o final do século XIX. Entretanto, atualmente, ainda não há consenso no que diz respeito às distintas tipologias que apresenta a vegetação no Estado do Rio Grande do Sul, nem quanto às terminologias a serem utilizadas de modo mais geral. Ao tratar especificamente das regiões Oeste e Sudoeste, o tema, "Fitogeografia" reveste-se de extrema importância, pois ainda apresenta pontos não bem esclarecidos na literatura científica. Frente a tal situação, os Estudos Fitogeográficos na Bacia Hidrográfica do Arroio Lajeado Grande - Oeste do RS, têm como objetivo principal, contribuir para o avanço do conhecimento fitogeográfico sul-rio-grandense. Para isto, inicialmente, foi realizada uma análise nas condições do meio físico, onde foram reconhecidas e diferenciadas, unidades morfolitológicas, com base nas características do relevo, do substrato rochoso e solos. Estas unidades foram representadas no mapa morfolitológico, que serviu de base geográfica à realização do levantamento florístico. Desenvolvido sob o aspecto fisionômico e ecológico, este levantamento revelou a existência de distintas tipologias na vegetação nativa. A partir de então, foi desenvolvido um estudo correlativo entre vegetação e meio físico, de modo a identificar os elementos do meio que exercem influência na composição florística e na distribuição espacial da cobertura vegetal. Esta correlação revelou que todas as tipologias, existentes na área em estudo, possuem estreitas relações com o meio físico, apresentando um padrão de distribuição geográfica. Em certas situações, tais relações são tão acentuadas que duas fanerófitas foram definidas como espécies geo-indicadoras de substrato rochoso. Os resultados obtidos nesta pesquisa foram representados em mapa fitogeográfico, definido a partir das tipologias de vegetação, em relação com as unidades morfolitológicas, sendo diferenciadas em: campos em colinas de arenito, campos com curupis (Sapium haematospermum Müll. Arg. Euphorbiaceae) em colinas de arenito, campos com butiá-anão (Butia lallemantii Deble & Marchiori Arecaceae) em colinas de arenito, campos em colinas vulcânicas, campos com espinilhos (Acacia caven (Molina) Molina - Leguminosae ou Fabaceae) em colinas vulcânicas, vegetação de cornijas, vegetação de morrotes de arenito, capões de mato e floresta de galeria. Espera-se que este trabalho sirva de subsídio a futuros estudos e propostas de conservação e preservação da biodiversidade e das paisagens naturais no Estado do Rio Grande do Sul.
57

Estudos floristicos, fitossociologicos e fitogeograficos em formações vegetacionais altimontanas da Serra da Mantiqueira Meridional, sudeste do Brasil / Floristic, phytossociology and phytogeography of the high-altitude vegetation of Serra da Mantiqueira Meridional, southeastern Brazil

Meireles, Leonardo Dias 14 August 2018 (has links)
Orientador: George John Shepherd / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-14T22:19:27Z (GMT). No. of bitstreams: 1 Meireles_LeonardoDias_D.pdf: 52013493 bytes, checksum: d5034b3efafae60949067d81a6753f38 (MD5) Previous issue date: 2009 / Resumo: A Serra Fina é o nome de umas das áreas da Serra da Mantiqueira Meridional, uma cadeia montanhosa na divisa geográfica entre Minas Gerais, São Paulo e Rio de Janeiro, sudeste do Brasil. A Serra Fina compreende um dos maciços de rochas alcalinas que forma uma das áreas de maior altitude dessa região com mais de 2.500 metros de altitude em vários locais. Ela apresenta um destacado gradiente altitudinal que permite a ocorrência de diferentes formações vegetacionais altimontanas. Sua vegetação apresenta-se ainda relativamente conservada, mas pouquíssimo conhecida. Nós objetivamos analisar a composição florística de suas formações vegetacionais altimontanas, descrever a estrutura fitossociológica das florestas nebulares, verificar a similaridade dessa floresta com outras florestas montanas brasileiras e verificar como mudanças climáticas quaternárias influenciaram a distribuição geográfica das espécies que as compõem. Nos campos de altitude, matas de candeias e nas florestas nebulares foram coletadas 393 espécies das quais sete são provavelmente novas para a ciência. As famílias Asteraceae, Poaceae, Melastomataceae, Rubiaceae, Cyperaceae, Fabaceae, Myrtaceae, Orchidaceae e Ericaceae apresentaram as maiores riquezas específicas. Duas espécies novas da família Asteraceae restritas aos campos de altitude acima de 2.500 metros de altitude foram descritas e ilustradas e as demais necessitam de estudos detalhados por especialistas. A riqueza específica amostrada denota a importância das áreas de altitude na diversidade da Floresta Atlântica e denotam a importância fitogeográfica da Serra Fina por apresentar um grande número de espécies endêmicas ou com distribuição geográfica restrita e comportar espécies com fortes relações com a flora dos Andes, oeste da América do Sul. As florestas apresentaram características típicas de florestas nebulares como menor riqueza, elevada densidade e um dossel reduzido. Myrsinaceae, Myrtaceae, Symplocaceae e Cunoniaceae foram as famílias de maior valor de importância. As florestas alto-montanas da Serra da Mantiqueira apresentaram alta similaridade florística com florestas nebulares sulinas e em parte com as florestas alto-montanas do interior de Minas Gerais e do topo da Serra do Mar em São Paulo, que apresentam uma composição florística relativamente diferenciada. A similaridade dessas florestas com florestas em altitudes mais baixas é relativamente menor. Os modelos de distribuição potencial para espécies florestais montanas destacaram intensas modificações na área de ocupação dessas espécies em cenários climáticos para o Quaternário Tardio e sugerem que estas espécies possam ter ocorrido em altitudes e latitudes menores e longitudes maiores do que atualmente observado. Esses resultados sugerem que florestas com composição florística similar às atuais florestas alto-montanas possam ter ocupado uma área mais extensa no passado, formando em algumas regiões florestas mais extensas que foram posteriormente fragmentadas e confinadas ao topo de cadeias montanhosas na região leste ao sul do Brasil. / Abstract: The "Serra Fina" is the name given to a block of the Serra da Mantiqueira, a mountain chain that forms the boundary between the states of Minas Gerais, São Paulo, and Rio de Janeiro, southeastern Brazil. The Serra Fina largely corresponds to a massif of alkaline rocks and forms the highest part of the range, rising to more than 2500m at several points. It offers an exceptionally extensive altitudinal gradient, with the occurrence of several high-montane vegetation formations. These formations are still relatively well-conserved, but are very poorly known. The main objectives of the present study were to analyze the floristic composition of some of the high-montane vegetation types, describe and analyze the phytosociological structure of the cloud forests, determine the degree of similarity between these forests and other montane forests in Brazil and to investigate possible explanations of the patterns seen, especially with regard to climate changes in the quaternary. A total of 393 species, of which seven are probably new to science, were collected in the grasslands, "candeia" scrub and cloud forests. The greatest species-level richness was found in the families Asteraceae, Poaceae, Melastomataceae, Rubiaceae, Cyperaceae, Fabaceae, Myrtaceae, Orchidaceae and Ericaceae. Two new species of Asteraceae, confined to grasslands above 2500m have been described and illustrated, and the remainder await more detailed studies by specialists. The species richness encountered demonstrates the importance of the contribution of high altitude areas to the overall diversity of the Atlantic Forest of eastern Brazil, and the phytogeographic importance of the Serra Fina with a large number of endemic species or species with restricted distributions with strong links to the Andean flora of western South America. The forests showed a number of characteristics typical of cloud forests, such as low richness, high density and a reduced canopy, with Myrsinaceae, Myrtaceae, Symplocaceae and Cunoniaceae as the most important families. The Serra da Mantiqueira upper montane forests showed their greatest floristic similarity to be with the cloud forests of southern Brazil and to some extent with the upper montane forests of the interior of Minas Gerais and the crest of the coastal range ("Serra do Mar") in São Paulo, though with a somewhat differentiated floristic composition. Similarities with the surrounding forest matrix at lower altitudes were much less. Models of potential distribution for montane forest species using scenarios for Late Quaternary conditions suggest that extensive modifications of currently observed distributions are likely to have occurred, with many species occupying much lower altitudes and latitudes, together with much greater longitudes. These results suggest that forests similar in composition to current upper montane forests may have occupied much more extensive areas in the past, forming an almost continuous forest that has subsequently been fragmented and confined to high mountain areas in the east-south Brazil. / Doutorado / Doutor em Biologia Vegetal
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A vegetação arborea em um gradiente altitudinal no Morro Cuscuzeiro, Ubatuba (SP) = uma analise floristica, fitossociologica e fitogeografica / Elevational gradient on the arboreal flora on Moutain Cuscuzeiro, Ubatuba (SP) : a phytogeographic, phytosociologic and floristic analysis

Bertoncello, Ricardo 10 May 2009 (has links)
Orientadores: Kikyo Yamamoto, George John Shepherd / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-15T02:40:57Z (GMT). No. of bitstreams: 1 Bertoncello_Ricardo_M.pdf: 8895754 bytes, checksum: 5b50a52fbb7e96dfd8126d57935601cf (MD5) Previous issue date: 2009 / Resumo: A classificação e a delimitação das diferentes formações fitogeográficas que ocorrem no domínio da Mata Atlântica nas regiões Sul e Sudeste do Brasil constituem um desafio para botânicos, ecólogos e fitogeógrafos. A distribuição atual destas formações está relacionada ao histórico de ocupação das áreas e a complexos gradientes ambientais, que ocorrem nos sentidos horizontal (latitudinal, longitudinal e edáfico) e vertical (altitudinal). Visando a contribuir para o conhecimento das formações florestais que integram a Mata Atlântica, este trabalho foi realizado no Morro do Cuscuzeiro (Ubatuba-SP) com os objetivos de: (1) descrever as variações florísticas e estruturais nas comunidades arbóreas em função da altitude, e verificar se existe uma Floresta Nebular que possa ser discriminada por parâmetros florísticos e estruturais; e (2) verificar a situação fitogeográfica das comunidades encontradas neste local no contexto da Mata Atlântica nas regiões Sul e Sudeste do Brasil. O Morro do Cuscuzeiro se situa no Núcleo Picinguaba do Parque Estadual da Serra do Mar (23° 18' 14" S e 44° 47' 16" W) e possui 1277m de altitude. O gradiente altitudinal foi representado por amostras de quatro cotas altimétricas, 820m, 970m, 1120m e 1270m, obtidas em 10 parcelas de 10 x 10 m em cada cota, exceto na mais alta que foi dividida em duas 'sub-cotas' com 5 parcelas cada. O critério de inclusão amostral da flora arbórea foi de 15 cm de CAP (exceto nas duas 'sub-cotas' superiores, 10 cm de CAP). Em sentido base-topo, foi verificada diminuição na riqueza, na diversidade, na altura, no diâmetro e no volume das árvores, e aumento na densidade. Uma mudança abrupta na composição da comunidade arbórea foi detectada a 1120m, acima da qual aparece uma formação que identificamos como Floresta Nebular, em substituição à floresta de encosta da Serra do Mar, que ocorre abaixo daquela altitude. As espécies destas duas formações florestais foram inseridas em uma matriz de 1546 espécies registradas em 112 levantamentos de 78 localidades do domínio da Mata Atlântica nas regiões Sul e Sudeste do Brasil. As análises multivariadas resultaram em cinco grupos de levantamentos: 1-Florestas Nebulares; 2- Florestas da província costeira (posteriormente sub-dividido em (a) Florestas de encosta e (b) Florestas de topo de morro e florestas da planície costeira); 3-Florestas de Araucária; 4-Florestas Semi-decíduas; e 5- Florestas Semi-decíduas Montanas. As formações encontradas no Morro do Cuscuzeiro foram incluídas nos grupos das Florestas Nebulares (de 1120m e 1270m) e das florestas de encosta da província costeira (820m e 970m), o que reforçou os resultados da análise dos dados locais, mostrando que pequenas diferenças em altitude podem resultar em mudança abrupta na composição das comunidades, evidenciada pela presença de espécies de distribuição disjunta que são compartilhadas com outras formações de Florestas Nebulares das regiões Sul e Sudeste do país / Abstract: The classification and delimitation of different vegetational formations into a phytogeographic system in Brazil has been a challenge to ecologists, botanists, and phytogeographers. The current distribution of these formations is related to historical process of land use and complex environment gradients, occurring in horizontal (latitude, longitude and edafic) and vertical (altitude) ways. The aims of this study were (a) to describe the changes in floristic composition and structure of tree species along an elevational gradient on Morro do Cuscuzeiro, Ubatuba (SP), and to verify the occurrence of a Cloud Forest that can be discriminated by floristic and structural paremeters; and (b) to analyze the phytogeographic position of the communities found in this mountain in relation to other surveys of the Atlantic Rain Forest domain in Southern and Southeastern Brazil. Mountain Cuscuzeiro is located in the Serra do Mar State Park (at 23° 18' 14" S, 44° 47' 16" W it is 1277m in height). A survey of tree species was made in four elevational levels, 820m, 970m, 1120m, and 1270m, using 10 samples of 10x10m on each level, except on the higher one, which was sub-divided in two sub-levels whith five samples on each. The sampling criterion was 4,8cm of DBH (except in the two higher sub-levels, where 3,2cm of DBH was used). The analysis resulted in consistent groups at the different levels, indicating a strong altitude influence on the floristic composition. An abrupt change of the vegetation was identified at 1120m, from where a typical Ombrophilous Dense Forest (slope forest from 820m to 970m) shifted into a Cloud Forest formation (1120m to 1270m). These two formations were inserted in a matrix made by a total of 1546 species of 112 surveys from 78 locations of Atlantic Rain Forest domain in southern and southeastern Brazil. The multivariate analysis resulted in five groups of samples: 1- The Cloud Forest; 2- The coastal province (further subdivided into (a) the slope forests and (b) a subgroup composeded by the mountaintop and the coastal plain forests); 3- The Araucaria Forest; 4-The Semi-Deciduous Forest; and 5- The Montane Semi-Deciduous Forest. The formations found on Mt. Cuscuzeiro were included in the groups of the Cloud Forest (from 1120m to 1270m) and of the Coastal Province (from 820m to 970m), which reinforced the results of the local elevational gradient analysis, showing that minor changes on altitude can lead to abrupt changes in community composition due to the occurrence of species with disjunct distribution that are shared with other Cloud Forest formations of southern and southeastern Brazil / Mestrado / Biologia Vegetal / Mestre em Biologia Vegetal
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Etudes floristique, phytosociologique et phytogéographique de la végétation du Parc Régional du W du Niger

Mahamane, Ali January 2005 (has links)
Doctorat en Sciences / info:eu-repo/semantics/nonPublished
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Relações florísticas, estruturais e ecológicas entre as florestas do topo da Serra do Mar e as florestas de restinga no Estado de São Paulo / Floristic, structural and ecological relationships between restinga florest and upper montane rain florest in Serra do Mar, SP, Brazil

Micheletti Neto, Joao Carlos Miguel Tomaz 18 December 2007 (has links)
As comunidades florestais periféricas às florestas que recobrem o sopé e as médias encostas da Serra do Mar apresentam uma convergência de fisionomias e aspectos xeromórficos, sustentada por floras que estão relacionadas quanto às suas origens. Como estas semelhanças podem indicar condições ecológicas similares, o trabalho investigou qualitativa e quantitativamente se as semelhanças fisionômicas, entre a Floresta do Topo dos Morros da Serra do Mar e a Floresta Seca de Restinga no Estado de São Paulo, são acompanhadas por semelhanças florísticas e estruturais. Esta investigação teve como objetivos: caracterizar e comparar, em termos fitossociológicos, as florestas secas de restinga e as florestas do topo das escarpas atlânticas; e analisar as relações entre possíveis padrões florísticos e estruturais do componente arbóreo destas florestas e condições edáficas e climáticas de seus ambientes. A amostragem foi realizada a partir de 10 parcelas de 10 m X 10 m em cada uma das seis áreas de estudo. Para o topo da Serra do Mar considerou-se a floresta nas seguintes Unidades de Conservação: Estação Biológica de Boracéia; Núcleo Curucutu do PESM e Parque Estadual Intervales. Para a floresta seca de restinga, as áreas de estudo foram: Núcleo Picinguaba do PESM, Estação Ecológica Juréia-Itatins e Parque Estadual Ilha do Cardoso. Através da descrição fitossociológica das comunidades e de técnicas de análise multivariada para classificação e ordenação, observou-se que as áreas de floresta do topo das encostas são pouco similares florística e estruturalmente em relação às florestas secas de restinga. As pequenas semelhanças entre as florestas estudadas dizem respeito às espécies de grande plasticidade ecológica e que, por isso, possuem ampla distribuição geográfica. As diferenças florísticas e estruturais foram determinadas pelas espécies oriundas das florestas que recobrem as encostas da Serra do Mar, sendo que nehuma das espécies consideradas importantes é endêmica de um dos tipos florestais, não sustentando, assim, a convergência ecológica. / Plant communities at the periphery of the Atlantic rainforest that recover the lower and middle slopes of Serra do Mar presents a convergence of physiognomy and xeromorphycs aspects, supported by floras that are related on its origins. As these convergence can indicate similar ecological conditions, this present work investigated if the similarities between Upper Slope Forest and the Restinga Forest in the State of São Paulo, Brazil, are followed by floristic and structural similarities. This inquiry had two objectives: characterize and compare the Upper Slope Forest and the Restinga Forest in its phytosociological aspects; analyze the relationships between edaphic and climatic conditions and floristic and structural patterns of the arboreal component of these forests. To characterize the Upper Slope Forest was considered forests in the following Conservation Units: Estação Biológica de Boracéia, Núcleo Curucutu do Parque Estadual da Serra do Mar and Parque Estadual Intervales; and to characterize the Restinga Forest the study areas were in the following Conservation Units: Núcleo Picinguaba do PESM, Estação Ecológica Juréia-Itatins and Parque Estadual Ilha do Cardoso. For structural vegetation analysis, were used 10 plots of 10 x 10 m in each area. The phytosociological description and multivaried analysis of classification and ordination showed that areas of Upper Slope Forest and Restinga Forest have low similarity. The resemblances are based on occurrence of broad ecological plasticity species and, therefore, of wide distribution. On the other hand, the floristic and structural heterogeneity is consequence of the predominance, in each forests type, of different species from the Atlantic rainforest that recover the lower and middle slopes of Serra do Mar, not supporting the ecological convergence hypothesis.

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