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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

Woody Floristic Composition of the Secondary Forest Permanent Plot of Nanjenshan Area

Liao, De-Chih 15 September 2000 (has links)
The purpose of this study is to understand the composition of the secondary forest of Nanjenshan area. A 5-ha plot was established at altitudes 200-264m on the north ridge of Nanjenshan. All free-standing woody plantsin the plot with DBH¡Ù1cm were identified, measured, tagged and mapped. A total of 108 tree species belonging to 40 families and 77 genera was recorded. The dominant species are Acacia confusa, Lagerstroemia subcostata, Psychotria rubra, Ficus septica¤ÎDendrocnide meyeniana. The dominant families are Fabaceae, Moraceae, Euphorbiaceae, Rubiaceae¤ÎLythraceae. TWINSPAN analysis reveales four groups. Group 1 is dominanted by Acacia confusa, Glochidion philippicum and Psychotria rubra. Group 2 is dominanted by Acacia confusa, Psychotria rubra and Lagerstroemia subcostata. Group 3 is dominanted by Acacia confusa, Psychotria rubra and Glochidion rubrum. Group 4 is dominanted by Acacia confusa, Lagerstroemia subcostata and Dendrocnide meyeniana. There are four kind of distribution pattern in this plot. Machilus obovatifolia and Osmanthus marginatus occurred on the hilltop; Dendrocnide meyeniana and Ficus virgata occurred on the middle-woody site; Zanthoxylum ailanthoides and Wendlandia uvariifolia only occurred along the steamside; Acacia confusa and Psychotria rubra were commonly distributed over the plot.
2

Biomechanical study of foot with hallux valgus deformity

Eshraghi, Saba January 2015 (has links)
Background: Hallux valgus (HV) is one of the most common foot deformities. Considering the fact that 23% of adults develop such condition during their lifetime, understanding HV is badly needed. Plantar pressure technologies are used widely for determination of biomechanical changes in foot during walking. There are already published claims relating to the pressure distribution of HV condition. Association of HV to sole pressure widely presented as a means of identifying such condition. Methods: plantar pressure patterns can be linked to the deformity progression or existence, extracting some patterns out of force measurements can be beneficial in recognizing the patients with and without deformity. The dynamic changes of the forces that applied to the fore-foot in volunteers with and without HV when they walked at self-selected and fast speeds were examined. Furthermore, Markovian chain transfer matrices were used to obtain the transfer coefficient of the force among five metatarsals. Another method was to measure the lateral flexibility of the 1st metatarsal joint as an indication of HV deformity by Motion Capture cameras. Finally, two 3D feet models of HV and non-HV volunteers were made in Mimics software and then in FEA (finite element analysis) the stress distribution under the foot was validated with the experiments. Results: The higher forces were observed under the 2nd, 3rd and 1st metatarsal heads in both speeds but the results obtained were significantly different among groups and in fast speed and under 3rd and 1st metatarsals in self-selected speed. In this study the use of Markovian transfer matrices as a means of characterising the gait pattern is new and novel. It was intended that highest coefficients of the matrix would indicate the existence of HV, however studies showed that the biggest difference between HV and non HV patients was the scatter of the coefficients which shown to give very strong indication of the existence of HV. It was shown by kinematic studies and also it was found that the 1st metatarsal joint was significantly more flexible in HV patients compared to non–HV individuals. Finally FEA studies has shown that in the 3D feet models of both volunteers (with and without HV), the highest stress was under the heal area and then transfers towards fore-foot area. In patient with HV the higher force were seen under the 1st to 3rd metatarsal heads compare to non-HV individual and each model was validated its related experiments. Conclusion: it was observed that there was a significant variability of pressure distribution of the same individual from one trial to another indicating that getting consistent pressure pattern is an important hurdle to overcome in our studies, raised loading is observed on Metatarsal 2, 3 and 1 in HV patients and it was possible to give statistical significance to these findings. In this thesis, it was intended to obtain early diagnostics of HV condition and much work was put in this, however outcome was not conclusive. However it was possible to distinguish HV form non-HV volunteers from the scatter characteristics of the transfer pattern. Investigation of the 1st metatarsal joint laxity of non-HV and HV patients revealed that HV individuals were significantly higher compared to non–HV volunteers and this can be used as an indication of HV existence. Finally, the 3D models show that FEA is a reliable tool as the FEA study showed good correlation with the experimental results.
3

The Influence of Habitat Quality on the Community Structure, Distribution Pattern, Condition, and Growth of Coral Reef Fish: A Case Study of Grunts (Haemulidae) from Antigua B.W.I, A Small Island System

Constantine, Sherry Lynette 25 July 2008 (has links)
The goal of this research was to determine the relative quality of near shore marine areas by investigating their influence on Haemulidae community structure, distribution pattern, condition, and growth. Habitat was defined at the small spatial scale of individual habitat types such as seagrass beds, mangroves and coral reefs, and at the broader spatial scale of the interconnection of these individual habitat types within a mosaic (IHM). Ten spatial, biotic and abiotic parameters (percentage coverage of sand, mangroves, hard substrate, and seagrass, turbidity, pH, salinity, temperature, average depth, and predator density) were investigated. These environmental characteristics acted as proxies for the quality of IHMs. The major findings of the research were: (1) IHMs and discrete habitat types in tropical marine systems are not always equal in quality. Further, the highest quality IHMs/discrete habitat types have the critical resources whether spatial, abiotic or biotic, at the optimum levels needed by organisms to carry out their critical life functions; (2) IHMs of the highest quality contain all the discrete habitat types needed by organisms to carry out their life processes in a spatial arrangement that maximizes energy savings; (3) IHMs can be of high quality in the absence of one habitat type, if this habitat type is replaced by another that can take on its ecological role; and (4) the percentage cover of hard substratum and seagrass, temperature, and predator density have a big impact on Haemulidae distribution pattern, community structure, condition and growth. In addition, this research highlighted some of many characteristics of benthic habitats such as type and configuration that should be included in the design of Marine Protected Areas for the effective management of fisheries resources. Effective Marine Protected Areas should have (1) large overall area with benthic habitat types of high quality; (2) spatial configurations with short distances (corridors) between habitat types; (3) spatial arrangements that place all individual habitat types in connection with all other habitat types so that energy expenditure in moving among habitat types is reduced; (4) habitats with high structural complexity; and (5) the inclusion of all the habitat types needed by focal organisms to carry out their life processes, or surrogate habitat types that can take on the role of ones that are absent.
4

Fitopedologia de disjunções (ilhas de mata) em uma área de savana do município de Boa Vista, Roraima

Naiara Marta Conceição dos Santos 30 August 2010 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O objetivo deste estudo foi o de entender os padrões fitopedológicos ocorrentes nas Formações Florestais (ilhas de mata) de uma área de savana do Município de Boa Vista, Roraima. Para tanto, foram amostradas quatro ilhas florestais localizadas nas áreas de savana do centro-leste de Roraima (Projeto de Assentamento Nova Amazônia I). Em cada ilha foram estabelecidas cinco trincheiras para classificação do solo, sendo uma central à ilha e mais quatro seguindo o direcionamento cardinal (leste, oeste, norte, sul), distanciadas 100 m uma das outras. De cada uma destas trincheiras foram estabelecidos quatro transectos lineares (4 m x 20 m) que, da mesma forma, foram montados seguindo as quatro direções cardinais, caracterizando um Cluster (grupo) de transectos. Cada um destes transectos se distanciava 3 m do centro das trincheiras para evitar sobreposição de medidas. Cada trincheira possuía uma profundidade de 200 cm como modal (trincheira central) e, as demais (pontos cardinais), com 40 cm. Nessas trincheiras foram coletadas amostras indeformadas e deformadas nas profundidades de 0 10 cm, 10 20 cm e de 20 40 cm. As amostras indeformadas foram utilizadas para estudo de densidade dos solos, enquanto as amostras deformadas, para análises físicas e químicas. Foi estabelecida uma amostragem florística para todos os indivíduos arbóreos com DAP (diâmetro à altura do peito) ≥ 10 cm presentes nos transectos estabelecidos a partir das trincheiras. Além do DAP, cada indivíduo inventariado teve sua altura total estimada (m), sendo que todos foram alvos de uma análise fitossociológica, por trincheira e por ilha. Os resultados indicaram que a principal classe de solos presente nas ilhas amostradas foram os Latossolos (12 trincheiras e 4 ilhas), seguidos de Plintossolo (6 trincheiras e 2 ilhas) e Latossolo vermelho Amarelo (2 trincheiras e 1 ilha). As espécies arbóreas de maior representatividade geral foram Abarema floribunda (Benth.) Barney e J.W( Mimosaceae); Pouteria petiolata T. D. Penn (Sapotaceae) e Pouteria macrophilla (Lam.) Eyma (Sapotaceae), representando os maiores índices de valor de importância (IVI) de todo o levantamento. O padrão fitopedológico ordenado pela análise genérica (espécies x características físicas e químicas do solo) indicou que as Tabebuia incana A. H. Gentry, Tabebuia serratifolia (Vahl) Nichols e Sorocea cf. guilleminiana Gaudich são exclusivas de latossolo, onde há predominância de altas concentrações de alumínio tóxico e altas concentrações de Matéria orgânica média, Potássio e Magnésio, ambos associados a alta acidez (pH). Por outro lado, espécies como espécies Protium aracouchini (Aubl.) March e Pouteria petiolata T. D. Penn estão presentes apenas em tipologias com melhor fertilidade de solo, em especial com maiores concentrações de matéria orgânica média, magnésio, argila e baixa toxidez de Al. Os resultados apontaram que as ilhas de mata estudadas podem possuir mais de uma classe de solo determinando diferenças na composição florística e, portanto, definindo diferentes fitopedounidades. Estes achados são de extrema importância para tomadas de decisão que incorporem ações de conservação do solo e uso dos recursos naturais em encraves florestais derivados das áreas de savana de Roraima. / This study aimed at understanding the phytopedological patterns that happen in the forest formations (forest islands) of a savannah in area of Boa Vista, Roraima. For in such a way, four forest islands located in the savannah areas of the center-east of Roraima had been sampled. (Projeto de Assentamento Nova Amazônia I). In each island five trenches for classification of the soil had been established, being a central office to island and more four following the cardinal points (east, west, north, south), 100m one of the others. Each one of these trenches four linear transectos had been established (4m x 20m) in the same way, they had been following the four cardinal directions, characterizing a Cluster (group) of transectos. Each one of these 3 transectos was far 3m of the center of trenches to prevent overlapping of measures. Each trench possessed a depth of 200cm as modal (central trench) and the others (cardinal points), with 40cm. In these trenches had been collected deformed and formed samples in the depths of 0 - 10cm, 10 - 20cm and of 20 - 40cm. The deformed samples had been used for study of density of soil, while the deformed samples, for physical and chemical analyses. A vegetation sampling for all tree individuals was established with DAP (diameter to the height of the chest) ≥ 10cm in the transectos established from trenches. Besides the DAP, each inventoried individual had its total height esteemed (m), being that all had been the target of a phytosociological analysis, for trench and island. The results had indicated that the main kind of the sampled islands had been the Latossolos (12 trenches and 4 islands), followed of Plintossolo (6 trenches and 2 islands) and Yellow red Latossolo (2 trenches and 1 islands). The tree species of bigger general representation had been Abarema floribunda (Benth.) Barney and J.W (Mimosaceae); Pouteria petiolata T.D. Penn (Sapotaceae) and Pouteria macrophilla (Lam.) Eyma (Sapotaceae), representing the biggest of the index of value of importance (IVI) of all the survey. The phytopedology standard commanded by the generic analysis (species x physical and chemical characteristics of the soil) indicated that the Tabebuia incana A. H. Gentry, Tabebuia serratifolia (Vahl) Nichols and Sorocea cf. guilleminiana Gaudich is exclusive of Latossolo, where it has predominance of high toxic aluminum concentrations and high concentrations of organic Substance, Potassium and Magnesium, both associate the high acidity (pH). On the other hand, species as Protium aracouchini (Aubl.) March and Pouteria petiolata T.D. Penn are only in typologies with better soil fertility, in special with bigger concentrations of organic substance, magnesium, clay and low toxicity of Al. The results had pointed that the studied islands of bush can possess more than one type of soil, determining differences composition of vegetation and, therefore, defining different phytopedological units. These findings are of extreme importance for decision taking that incorporates action of conservation of the soil and use of the natural resources in the forest derivatived of the savannah areas of Roraima.
5

Comments on the cybernetics of stability and regulation in social systems

Ben-Eli, M. U. January 1976 (has links)
The methods and principles of cybernetics are applied to a discussion of stability and regulation in social systems taking a global viewpoint. The fundamental but still classical notion of stability as applied to homeostatic and ultrastable systems is discussed, with a particular reference to a specific well-studied example of a closed social group (the Tsembaga studied by Roy Rappaport in New Guinea). The discussion extends to the problem of evolution in large systems and the question of regulating evolution is addressed without special qualifications. A more comprehensive idea of stability is introduced as the argument turns to the problem of evolution for viability in general. Concepts pertaining to the problem of evolution are exemplified by a computer simulation model of an abstractly defined ecosystem in which various dynamic processes occur allowing the study of adaptive and evolutionary behaviour. In particular, the role of coalition formation and cooperative behaviour is stressed as a key factor in the evolution of complexity. The model consists of a population of several species of dimensionless automata inhabiting a geometrically defined environment in which a commodity essential for metabolic requirements (food) appears. Automata can sense properties of their environment, move about it, compete for food, reproduce or combine into coalitions thus forming new and more complex species. Each species is associated with a specific genotype from which the species’ behavioural characteristics (its phenotype) are derived. Complexity and survival efficiency of species increases through coalition formation, an event which occurs when automata are faced with an “undecidable” situation that is resolvable only by forming a new and more complex organization. Exogenous manipulation of the food distribution pattern and other critical factors produces different environmental conditions resulting in different behaviour patterns of automata and in different evolutionary “pathways.” Eve-1, the computer program developed to implement this model, accepts a high-level command language which allows for the setting of parameters, definition of initial configurations, and control of output formats. Results of simulation are produced graphically and include various pertinent tables. The program was given a modular hierarchical structure which allows easy generation of new versions incorporating different sets of rules. The model strives to capture the essence of the evolution of complexity viewed as a general process rather than to describe the evolution of a particular “real” system. In this respect it is not context-specific, and the behaviours which are observable in different runs can receive various interpretation depending on specific identifications. Of these, biological, ecological, and sociological interpretations are the most obvious and the latter, in particular, is stressed.
6

The effects of landscape features on the distribution and genetic structure of forest duikers (Cephalophinae) in the tropical forest of Moukalaba, Gabon / ガボン、ムカラバの熱帯林におけるダイカー亜科(Cephalophinae)の分布と遺伝構造に与える景観の影響

Akomo, Okoue Etienne Francois 24 November 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第19360号 / 理博第4122号 / 新制||理||1593(附属図書館) / 32374 / 新制||理||1593 / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 中川 尚史, 教授 中務 真人, 教授 曽田 貞滋 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
7

Diatom communities in lakes and streams of varying salinity from south-west Western Australia : distribution and predictability

Taukulis, Fiona E January 2007 (has links)
The distribution pattern of diatoms from lakes and streams of varying salinity in the south-west of Western Australia was investigated. A total of 95 water bodies were sampled and separated into freshwater (<3 ppt), hyposaline (3-20 ppt), mesosaline (20-50 ppt) and hypersaline (>50 ppt). The south-west and specifically the inland wheatbelt region has been severely influenced by secondary salinisation, due to clearing of native vegetation for agriculture. There has been little research on diatom communities from salt-affected systems, with this data providing the basis for the development of an inference model based on species optima and tolerance limits to salinity. Physico-chemical variables measured from the study sites were collated and assessed. Salinity ranged from freshwater (0.04) to hypersaline (156.80 ppt), and pH ranged from acidic (2.90) to alkaline (10.51). Dissolved oxygen levels were recorded from 1.11 to 18.67 mgL-1, water temperature from 6.30 to 28.10 °C and peripheral vegetation scores from 1 (little or no cover) to 5 (dense cover). Analysis of variance (ANOVA) showed that salinities were significantly higher in standing waters located further inland, compared to flowing waters in high rainfall areas. Hypersaline wetlands displayed significantly lower dissolved oxygen levels, higher water temperatures and reduced peripheral vegetation, compared to freshwaters. The pH of hypersaline sites was also significantly lower, associated with surrounding land use or underlying geology. The data collected provides important baseline information, with implications for aquatic biota. / The community structure of diatoms in relation to varying salinity concentration was explored. An artificial substrate collector (JJ periphytometer) was used to standardise sampling and ensure diatom assemblages were representative of ambient water quality. A total of 217 taxa were identified with the highest diversity observed in freshwater sites (up to 33 species), and limited to less than 15 in hypersaline waters. According to BIOENV, salinity was the key factor influencing diatom community structure. SIMPER analysis found a number of discriminating taxa between salinity ranges, specifically between assemblages from freshwater and hypersaline sites. Taxa such as Achnanthidium minutissimum and Gomphonema parvulum were indicative of freshwaters. In comparison, Amphora coffeaeformis and Nitzschia ovalis were associated with hypersaline water bodies. Diatom community structure was also examined from 20 hypersaline wetlands in the wheatbelt region with varying pH. Characteristic taxa including Amphora coffeaeformis, Hantzschia sp. aff. baltica and Nitzschia ovalis showed a wide tolerance to salinity and pH, or hypersaline acidic conditions. BIOENV analysis found there were no observable differences between diatom assemblages in relation to salinities above 50 ppt and that pH was highly correlated to species composition. The increasing occurrence of acid saline lakes is of concern and is most likely attributable to deep drainage practices and continued use of fertilisers in agricultural areas. / A diatom-based transfer function was developed from the south-west dataset, to document species optima and tolerance limits to salinity. CCA analysis showed that salinity accounted for a significant and independent amount of variation in the diatom data enabling an inference model to be derived. The most successful model was generated using tolerance-downweighted weighted averaging, with a high coefficient of determination and low prediction errors that remained high after jackknifing. The optima of freshwater diatoms were similar to those reported from other regions of the world, although the optima of hypersaline species tended to be higher. Comparatively, the model performed very well, with the potential to be applied in future paleolimnological studies. In conclusion, this study has shown diatoms to be effective biomonitoring tools, providing the basis for future sampling strategies that assess the biodiversity of salt-affected water bodies in Western Australia. Potential indicator species from different salinity ranges were identified and the sensitivity of diatoms allowed for the development of a statistically robust inference model for the south-west. The reported optima and tolerance limits of important taxa may be further explored to evaluate the success of remediation measures implemented for secondary salinised systems in this region.
8

Genetic, Age, and Spatial Structure to Improve Management of Common Privet (Ligustrum vulgare)

Zhao, Wanying 06 January 2012 (has links)
No description available.
9

Distribution des communautés végétales sous l'influence des lisières forestières dans des bois fragmentés / Distribution of vegetation communities under forest edge influence in fragmented forests

Alignier, Audrey 05 November 2010 (has links)
Les lisières forestières constituent un enjeu pour la gestion des territoires, par la biodiversité qu’elles abritent, les processus écologiques qu’elles régulent et les services environnementaux qu’elles rendent à l’agriculture et à la foresterie. C’est pourquoi il est nécessaire de connaitre et quantifier précisément leurs influences sur la végétation pour proposer des mesures de gestion adaptées à la variabilité des situations de lisière. En référence aux hypothèses de la littérature, ce travail vise à comprendre comment varie la répartition des communautés végétales forestières en réponse à la diversité des types de lisières, dans un paysage agriforestier. Les espèces vasculaires de la strate basse de la végétation forestière ont été recensées le long de 28 transects, représentatifs de sept types de lisières des coteaux de Gascogne. Ces transects, perpendiculaires à la bordure et dirigés vers l’intérieur du bois, comportent 20 quadrats contigus de 2 m × 2 m. J’ai cherché à mesurer la profondeur d’influence des effets de lisières sur la végétation par la méthode de régression à deux phases. Face à l’hétérogénéité observée, j’ai caractérisé les patrons de distribution des communautés végétales par cinq modèles continus pour les comparer. Les lisières structurent la répartition des communautés végétales suivant un gradient, de la bordure vers l’intérieur du bois, mais les patrons sont plus variables qu’attendus et remettent en cause la généricité du modèle théorique à deux phases largement admis dans la littérature. Néanmoins, un patron de distribution de la végétation commun à l’ensemble des lisières a été identifié au moyen de la méthode STATIS d’analyse à k-tableaux. L’analyse des effets de lisière sur un sous-échantillon d’espèces a été affinée par la prise en compte des caractéristiques biologiques et écologiques des espèces d’une part, et des variables environnementales, à différentes échelles spatio-temporelles d’autre part. Les traits biologiques et écologiques des espèces répondent davantage à l’âge et l’histoire des lisières qu’à la distance à la bordure. La hiérarchie des facteurs environnementaux, paysagers et historiques confirment le rôle prépondérant de la qualité locale de l’habitat dans la structure des communautés. La variabilité temporelle des effets de lisière a été abordée par un suivi horaire des variations microclimatiques au cours d’une année. Les faibles écarts microclimatiques entre la lisière et l’intérieur du bois au cours des saisons suggèrent un rôle faible du microclimat sur la structure des assemblages d’espèces. Enfin, la variabilité spatiale des lisières dans un paysage de large étendue a été évaluée par la mise au point d’une méthode originale afin de caractériser et cartographier la diversité des segments de lisières. Les résultats remettent en cause les modèles théoriques antérieurs et ouvrent des perspectives pour une meilleure compréhension des principes d’organisation des communautés végétales en lisières de forêt. La complexité des patrons de réponse aux effets de lisière justifie de porter une attention plus soutenue à la diversité des lisières dans la perspective de mieux les gérer. / Forest edges are a challenge for land management. They contain high biodiversity, regulate ecological processes and provide environmental services to agriculture and forestry. Therefore, it is necessary to evaluate and quantify precisely edge influence on vegetation to propose management measures adapted to edge diversity. Referring to the literature asusmptions, this paper focuses on understanding the variation in the distribution patterns of forest plant communities in response to contrasted edge types in rural landscape. All vascular plant species of the understorey forest vegetation have been identified along 28 transects, pertaining to seven edge types of “coteaux de Gascogne”. Transects were perpendicular to the forest border and included 20 contiguous quadrats of 2 m × 2 m, towards forest interior. I tried to measure the depth of edge influence on vegetation using the two-phase linear regression method. Facing to high heterogeneity, I characterized the distribution patterns of plant communities by five continuous models for comparison. Edge effect structure the distribution of plant communities along a gradient from the border toward the forest interior. Response patterns to edge influence were more variable than expected and challenge the hypothetical response model pattern widely accepted in the literature. However, a common pattern of vegetation for all transects was identified using the k-tables STATIS method. Analysis of edge effects on a sub-sample of species was refined using on the one hand biological and ecological species traits and environmental variables at different spatio-temporal scales, on the other. The functional response of plant species better suited to the age and history of the edges than the distance from the border. Nevertheless, the hierarchy of environmental, landscape and historical context confirm the role of habitat quality on distribution patterns of forest vegetation. Temporal variability of edge effects has been addressed by monitoring hourly microclimatic variations over one year. The small differences in microclimate between edge and forest interior over seasons suggest a weak role of microclimate on the structure of plant species assemblages. Finally, the spatial variability of edges at the landscape level has been evaluated. An original method, Cartolis, has been developed to characterize and map the diversity of forest edge segments. Our results, calling into question the earlier theoretical models, provide opportunities for a better understanding of plant distribution patterns in forest edges. The complexity of responses obtained warrants to bring more attention to edge diversity for better management and conservation of plant species.
10

Fatores abióticos condicionantes da distribuição de espécies arbóreas em quatro formações florestais do Estado de São Paulo / Abiotic factors determining spatial distribution of tree species in four forest formations of the State of São Paulo

Magalhães, Simone Rodrigues de 15 March 2016 (has links)
No estudo das comunidades florestais, estabelecer a importância relativa dos fatores que definem a composição e a distribuição das espécies é um desafio. Em termos de gradientes ambientais o estudo das respostas das espécies arbóreas são essenciais para a compreensão dos processos ecológicos e decisões de conservação. Neste sentido, para contribuir com a elucidação dos processos ecológicos nas principais formações florestais do Estado de São Paulo (Floresta Ombrófila Densa de Terras Baixas, Floresta Ombrófila Densa Submontana, Floresta Estacional Semidecidual e Savana Florestada) este trabalho objetivou responder as seguintes questões: (I) a composição florística e a abundância das espécies arbóreas, em cada unidade fitogeográfica, variam conforme o gradiente edáfico e topográfico?; (II) características do solo e topografia podem influenciar na previsibilidade de ocorrência de espécies arbóreas de ampla distribuição em diferentes tipos vegetacionais? (III) existe relação entre o padrão de distribuição espacial de espécies arbóreas e os parâmetros do solo e topografia? O trabalho foi realizado em parcelas alocadas em unidades de conservação (UC) que apresentaram trechos representativos, em termos de conservação e tamanho, das quatro principais formações florestais presentes no Estado de São Paulo. Em cada UC foram contabilizados os indivíduos arbóreos (CAP &ge; 15 cm), topografia, dados de textura e atributos químicos dos solos em uma parcela de 10,24 ha, subdividida em 256 subparcelas. Análises de correspodência canônica foram aplicadas para estabelecer a correspondência entre a abundância das espécies e o gradiente ambiental (solo e topografia). O método TWINSPAN modificado foi aplicado ao diagrama de ordenação da CCA para avaliar a influência das variáveis ambientais (solo e topografia) na composição de espécies. Árvores de regressão \"ampliadas\" (BRT) foram ajustadas para a predição da ocorrência das espécies segundo as variáveis de solo e topografia. O índice de Getis-Ord (G) foi utilizado para determinar a autocorrelação espacial das variáveis ambientais utilizadas nos modelos de predição da ocorrência das espécies. Nas unidades fitogeográficas analisadas, a correspondência entre o gradiente ambiental (solo e topografia) e a abundância das espécies foi significativa, especialmente na Savana Florestada onde observou-se a maior relação. O solo e a topografia também se relacionaram com a semelhança na composição florística das subparcelas, com exceção da Floresta Estacional Semicidual (EEC). As principais variáveis de solo e topografia relacionadas a flora em cada UC foram: (1) Na Floresta Ombrófila Densa de Terras Baixas (PEIC) - teor de alumínio na camada profunda (Al (80-100 cm)) que pode refletir os teor de Al na superfície, acidez do solo (pH(H2O) (5-25 cm)) e altitude, que delimitou as áreas alagadas; (2) Na Floresta Ombrófila Densa Submontana (PECB) - altitude, fator que, devido ao relevo acidentado, influencia a temperatura e incidência de sol no sub-bosque; (3) Na Savana Florestada (EEA) - fertilidade, tolerância ao alumínio e acidez do solo. Nos modelos de predição BRT, as variáveis químicas dos solos foram mais importantes do que a textura, devido à pequena variação deste atributo no solo nas áreas amostradas. Dentre as variáveis químicas dos solos, a capacidade de troca catiônica foi utilizada para prever a ocorrência das espécies nas quatro formações florestais, sendo particularmente importante na camada mais profunda do solo da Floresta Ombrófila Densa de Terras Baixas (PEIC). Quanto à topografia, a altitude foi inserida na maioria dos modelos e apresentou diferentes influências sobre as áreas de estudo. De modo geral, para presença das espécies de ampla distribuição observou-se uma mesma tendência quando à associação com os atributos dos solos, porém com amplitudes dos descritores edáficos que variaram de acordo com a área de estudo. A ocorrência de Guapira opposita e Syagrus romanzoffiana, cujo padrão variou conforme a escala, foi explicada por variáveis com padrões espaciais agregados que somaram entre 30% e 50% de importância relativa no modelo BRT. A presença de A. anthelmia, cujo padrão também apresentou certo nível de agregação, foi associada apenas a uma variável com padrão agregado, a altitude (21%), que pode ter exercido grande influência na distribuição da espécie ao delimitar áreas alagadas. T. guianensis se associou a variáveis ambientais preditoras com padrão espacial agregado que somaram cerca de 70% de importância relativa, o que deve ter sido suficiente para estabelecer o padrão agregado em todas as escalas. No entanto, a influência dos fatores ambientais no padrão de distribuição da espécie não depende apenas do ótimo ambiental da espécie, mas um resultado da interação espécie-ambiente. Concluiu-se que: (I) características edáficas e topográficas explicaram uma pequena parcela da composição florística, em cada unidade fitogeográfica, embora a ocorrência de algumas espécies tenha se associado ao gradiente edáfico e topográfico; (II) a partir de características dos solos e da topografia foi possível prever a presença de espécies arbóreas, que apresentaram particularidades em relação a sua associação com o solo de cada fitofisionomia; (III) a partir de associações descritivas o solo e a topografia influenciam o padrão de distribuição espacial das espécies, na proporção em que contribuem para a presença das mesmas. / In the study of forest communities, establish the relative importance of the factors that define the composition and distribution of species is a challenge. In terms of environmental gradients study the responses of tree species are essential to the understanding of ecological processes and conservation decisions. In this regard, to contribute to the elucidation of ecological processes in the main forest formations of São Paulo (Dense Ombrophylous Forest of Lowlands, Submontane Dense Ombrophylous Forest, Semideciduous Forest and Savanna Woodland) this study aimed to answer the following questions: (I) floristic composition and tree species abundance in each phytogeographic unit change according to edaphic and topographic gradient?; (II) soil characteristics and topography can influence the occurrence of predictability of tree species widely distributed in different types of vegetation? (III) there is a relationship between spatial distribution pattern of tree species and the soil parameters and topography? The work was carried out in allocated plots in protected areas (PA) with the four main forest formations in terms of conservation and size of Sao Paulo. In each PA was sampled individual trees, topography, texture data and chemical properties of the soil on a plot of 10.24 ha, subdivided into 256 subplots. Canonical corresponding analyzes (CCA) were applied to establish the correspondence between the abundance of species and environmental gradient (soil and topography). The modified TWINSPAN method was applied to CCA ordination diagram to evaluate the influence of environmental variables (soil and topography) on species composition. Boosteed Regression Trees (BRT) were adjusted for predicting the occurrence of the species according to soil variables and topography. The Getis Ord-index (G) was used to determine the spatial autocorrelation of environmental variables used in the BRT models. In analyzed phytogeographic units, correspondence between the environmental gradient (soil and topography) and abundance of species was significant, especially in Savanna Woodland. The soil and topography also correlated with the floristic composition similarity of the subplots, with the exception of Semicidual Seasonal Forest (EEC). The main soil and topography variables related to floristic in each PA were: (1) Dense Ombrophylous Forest of Lowlands (PEIC) - aluminium content in the deep layer (Al (80-100 cm)) which may reflect the Al content at the surface, soil acidity (pH (H2O) (5-25 cm)) and altitude, which outlined the flooded areas; (2) Submontane Dense Ombrophylous Forest (PECB) - elevation, due to the rugged terrain influences the temperature and light incidence in the understory; (3) Savanna Woodland (EEA) - fertility, tolerance to aluminum and soil acidity. In BRT prediction models, the chemical soil variables were more important than the texture due to small variation of this soil attribute in the sampled area. Among the soil chemical variables, cation exchange capacity was used to predict the species occurrence in four forest formations and particularly important in the soil deepest layer on the Dense Ombrophylous Forest of Lowlands (PEIC). In relation to topography, elevation was included in most models and had different influences on the study areas. Overall, the species widely distributed showed the same trend as the association with the attributes of the soil, but with amplitudes of edaphic descriptors that change according to the study area. The occurrence of the Guapira opposita and Syagrus romanzoffiana, whose pattern change according to the scale, was explained by variables with aggregated spatial patterns that amounted to between 30% and 50% relative importance in the BRT model. The presence of A. anthelmia, which defaults also presented certain level of aggregation, was associated only with one aggregate variable, elevation (21%), which may have exerted great influence on the species distribution to delimit wetlands. T. guianensis was related with the predictive environmental variables of aggregate spatial pattern which totaled to about 70% relative importance, what must have been enough to establish the aggregate pattern at all scales. However, the influence of environmental factors (soil and topography) on the species distribution pattern depends not only on the environmental optimum of the species, but a result of species-environment interaction. We concluded that: (I) soil and topographical characteristics explain a small portion of the floristic composition in each phytogeographic unit, although the occurrence of some species have been associated to the soil and topographic gradient; (II) from soil characteristics and topography it was possible to predict the presence of tree species, which showed particular in relation to its association with the soil of each vegetation type; (III) from descriptive associations soil and topography influence the spatial distribution pattern of the species, to the extent that contribute to the presence of the same.

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