Esta tese foi concebida para se integrar ao eixo nº 5 (Paleoclimas e Paleoambientes no final do Peistoceno e Holoceno na região de Lagoa Santa) da terceira versão do projeto temático Origens e Microevolução do Homem na América: uma abordagem paleoantropológica (FAPESP proc. 04/01321-6), onde a principal questão abordada é a existência de um grande período (de 8.000 a 2.000 anos A.P) de drástica redução de sepultamentos e vestígios arqueológicos na região de Lagoa Santa, MG. Para esse período, as pesquisas palinológicas no Brasil central e sudeste, embora existam em número razoável, possuem interpretações paleoambientais contraditórias. Bem caracterizado no Hemisfério Norte, ao redor de 6000 anos A.P., o evento climático conhecido como Ótimo Climático, período predominantemente mais quente e úmido, se estabeleceu devido a uma maior insolação terrestre, propiciando a expansão de coberturas vegetais de maior porte e umidade de diversos pontos do globo e é sustentado por diversos autores para muitas localidades brasileiras. Por outro lado, embora não existam dúvidas de que o nível do mar esteve acima do atual na costa brasileira, é consenso que alterações climáticas foram mais amenas e aparentemente mais complexas. Amparados por este raciocínio, outros estudos sugerem eventos de seca no período aproximado de 6000 a 4500 anos A.P. Neste contexto, objetivando verificar a provável diferença climática ocorrida durante o Holoceno médio é confirmada pelo estudo de lenhos fósseis de região e sustenta a hipótese de a redução de sepultamentos da região reflete um deslocamento humano por causas climáticas, utilizaram-se duas abordagens diferentes no estudo anatômico de lenhos fósseis datados do Holoceno médio e tardio: uma abordagem florística, feita através da identificação taxonômica das amostras fósseis e comparação com localidades atuais; e através de uma abordagem anatômico-ecológica do lenho de Myroxylon peruiferum L.f., que utilizou correlações existentes entre o clima e as características anatômicas pra predizer o clima pretérito da região com base nas características anatômicas dos fósseis. Para a primeira abordagem, foram também realizados um levantamento florístico-lenhoso da APA Carste de Lagoa Santa e estudos fitossociológicos nas diferentes fitofisionomias da região, que proveram informações adicionais para as interpretações paleoambientais. Como resultado, os estudos florísticos e fitossociológicos, além de grande valia para a interpretação das assembléias fósseis, mostraram uma riqueza expressiva de espécies na região. A identificação das assembléias fósseis do Holoceno médio e tardio mostrou muita similaridade entre as duas assembléias, sugerindo a ausência de mudanças climáticas significativas a ponto de alterar a florística da região. Ainda, essas assembléias fósseis são relacionadas fortemente com o mosaico de vegetações existentes na região, que aponta para a manutenção desta vegetação desde o Holoceno médio. Por outro lado, a abordagem anatômico-ecológica revelou uma maior sazonalidade climática durante o Holoceno médio. Embora pareçam conflitantes, estes resultados são interpretados como complementares, e indicam um período sensivelmente mais sazonal no Holoceno médio, porém insuficientes para propiciar alterações florísticas no mosaico vegetacional que existia na época e caracteriza hoje a região. Esses resultados, portanto, não apóiam a hipótese de alterações intensas no clima, na flora e nem na presença das vegetações que ali existiam desde 5.000 anos A.P. / This thesis is designed to integrate the shaft Nº. 5 (Paleoclimates and paleoenvironments in the Late Pleistocene and Holocene at Lagoa Santa region) of the third version of the Project Origins and Microevolution of man in América: an approach paleoanthropological (FAPESP proc. 04/01321-6), where the main issue addressed is the existence of a large period (8000-2000 years BP) of drastic reduction of burials and archaeological sites in Lagoa Santa, MG. For that period, palynological research in central and southeastern Brazil, althoug in reasonable numbers, have contradictory paleoenvironmental interpretations. Well characterized in the Northern Hemisphere, around 6000 yeras BP, the climatic event known as Climatic Optimum, predominantly warmer and wetter, was established due to greater solar insolation, favoring the expansion of humid vegetation cover various parts of the globe and is supported by several authors for many places in Brazil. Moreover, although there is no doubt that the sea level was above the current along the Brazilian coast, there is consensus that climate change was milder and seemingly more complex. In the same way, other studies suggest drought events in the approximate period 6000 to 4500 years B.P. In this context, to verify if the climatic differences likely ocurred during the middle Holocene is confirmed by the study of fóssil Wood from the region and supports the hypothesis that the reduction of burials in the region reflects a human migration causes climate, we used two different approaches in a anatomical study of fóssil Wood dated to the middle and late Holocene: 1.) a floristic approach, made through the taxonomic identification of fóssil specimens and comparison with current local florist, and 2.) through na approach of ecological Wood anatomy of Myroxylon peruiferum L.f., which correlation between climate and anatomical characteristics were used to predict the past climate of the region based on the same anatomical characteristics in fossils samples. For the first approach, were also carried out a floristica-woody survey of APA-Lagoa Santa Karst and phytosociological studies in different Forest types in the region, which provided additional information for paleoenvironmental interpretations. As a result, floristic and phytosociological studies, besides showing great importance for the interpretation of fóssil assemblages, revealed and expressives richness of species. The identification of fóssil assemblages from middle and late Holocene showed high similarity between both, suggesting the absence of enough climate change lo alter the flora in the region. Still, these fóssil assemblages are strongly related with the mosaico of vegetation in the region, pointin to the maintenance of vegetation since the middle Holocene. Furthermore, the ecological-anatomy approach revealed a greater climatic seasonality during the middle Holocene. Although these two approaches seem conflicting, these results are interpreted as complementary, and show a markedly more seasonal period in middle Holocene, but insufficient to provide floristic changes in the vegetation mosaic that existed nowadays and characterizes the region. These results therefore do not support the hypothesis of intense changes in climate, flora and even in the presence of vegetation that existed there since 5000 years BP.

Global warming and its influence on the environment has become a popular and widespread issue. Nowadays, an analogy of a high latitude ecosystem during the greenhouse type of climate does not exist. The Cretaceous polar ecosystem gave us a unique possibility of understanding these extreme ecosystems and the specific adaptations of organisms to these conditions. Such types of ecosystem are crucial for a better understanding of possible future climate changes. This thesis focusses on the adaptation strategies of land plants during the Late Cretaceous in the Arctic peninsula. The land plants responded to these specific solar conditionals in two different ways: evergreen or deciduous. The fossil material for this study comes from Brandy Bay and Crame Col, James Ross Island, Antarctic. The material was collected in a continuous sequence from Kotic point to Santa Marta Formation (Cenomanian - Companian). A detailed and systematic analysis was performed on five out of fifty-five samples that well represented the studied region and age: Agathoxylon kellerense, Agathoxylon antarcticus, Araucarioxylon chapmanae, Podocarpoxylon multiparenchymatosum and Phoroxylon sp. Based on the detailed study of Agathoxylon kellerense (sample number AN34) wood anatomy and growth rings structure, adaptation strategies were...

Global warming and its influence on the environment has become a popular and widespread issue. Nowadays, an analogy of a high latitude ecosystem during the greenhouse type of climate does not exist. The Cretaceous polar ecosystem gave us a unique possibility of understanding these extreme ecosystems and the specific adaptations of organisms to these conditions. Such types of ecosystem are crucial for a better understanding of possible future climate changes. This thesis focusses on the adaptation strategies of land plants during the Late Cretaceous in the Arctic peninsula. The land plants responded to these specific solar conditionals in two different ways: evergreen or deciduous. The fossil material for this study comes from Brandy Bay and Crame Col, James Ross Island, Antarctic. The material was collected in a continuous sequence from Kotic point to Santa Marta Formation (Cenomanian - Companian). A detailed and systematic analysis was performed on five out of fifty-five samples that well represented the studied region and age: Agathoxylon kellerense, Agathoxylon antarcticus, Araucarioxylon chapmanae, Podocarpoxylon multiparenchymatosum and Phoroxylon sp. Based on the detailed study of Agathoxylon kellerense (sample number AN34) wood anatomy and growth rings structure, adaptation strategies were...

To evaluate the compression wood response in eastern white pine (Pinus strobus L.) following a severe ice storm in 1994, 47 trees were felled in 2007 and cross-sectional samples were collected at 0.5 (±0.2) m stem height. The disks were sanded and digitally scanned, and the cross-sectional area (mm2) of compression wood within each tree-ring was quantified using image analysis software. Topographic data (slope, aspect, and elevation) were also recorded for each P. strobus tree, along with a modified competition index. Wood anatomical features were also quantified in the three years before and after the storm along a tree diameter gradient. Although tree age was relatively constant in this stand, tree size was influenced by topographic position; larger trees grew in the valley while smaller trees were found growing in thin soils at the mid-slope position. When the cohort was about 25 years old, ice deposition caused a heterogeneous compression wood response which was highly related to tree size. In the thirteen years following the ice storm, the 6 – 9 cm (2007) diameter class formed significantly more compression wood area than any other, followed by the 10 – 13 cm (2007) diameter class. The tree diameter range that formed the most post-storm compression wood was 4 – 8 cm at the time of the storm, suggesting that this diameter range was most affected by 8.5 cm of ice loading in P. strobus. Trees > 18 cm in 1994 did not form any compression wood after the storm, but many experienced a growth release to fill canopy gaps. Topographic variables did not influence compression wood formation directly, but only one plot was sampled so these results are tenuous. However, topography did influence tree size which was the most important predictor in compression wood. There was no relationship between compression wood area and competition index. Due to compression wood formation after the ice storm, cell wall thickness and cell circularity were significantly higher in the 1994 tree-ring than in other rings examined (1991 – 1993, 1995, and 1996). Tracheid and lumen diameters were significantly smaller in compression wood cells (30.5 and 19.5 μm, respectively) than in normal wood (36.8 and 28.4 μm, respectively); opposite wood cells were intermediate in size (32.4 and 24.4 μm, respectively). Due to small tracheid size, compression wood contained significantly more cells mm⁻¹ (33) than normal wood (27), but no significant differences in cell wall area. Therefore, cumulative cell wall area occupied 47% of the cross-section in compression wood tissue on average, compared to 31% in normal wood. Dispersing tree weight across a greater surface area may help compression wood to prop up a bent tree, but reduced lumen area may also impact hydraulic conductivity in the stem. / Master of Science

No description available.

En 2011, cinq (5) cultivars de saules ont été sélectionnés pour leur rendement en biomasse. Ils ont été plantés sur quatre sites de la province du Québec et ont été maintenus selon le protocole de la culture intensive sur courtes rotations (CICR) afin de déterminer leur potentiel pour la bioénergie dans des environnements contrastés. La composition et l’anatomie du bois de ces cultivars ont été caractérisées et comparés en fonction des conditions environnementales caractéristiques de chaque site. La hauteur et le diamètre à la base des plantes diffèrent selon les sites. Ainsi, les cultivars répondent de façon spécifique aux conditions pédoclimatiques dans lesquelles ils sont cultivés. L’effet de l’environnement n’a pas été mis en évidence sur la teneur en lignine des cultivars. Cependant, un effet génotypique a pu être constaté soulignant l’importance de la sélectivité des cultivars. La densité du bois a étonnamment conservé la même hiérarchie génotypique entre les sites. À l’opposé, l’anatomie du bois présente des différences notamment au niveau des caractéristiques des fibres et des vaisseaux. Une forte teneur en polyphénols ainsi que des fibres moins larges et des vaisseaux plus nombreux ont été observés sur le site dont le bois est le plus dense supposant l’effet probable d’un stress abiotique. De plus, deux fois plus de fibres gélatineuses, fibres riches en cellulose, ont été identifiées sur ce site montrant un intérêt pour la production de bioéthanol. / In 2011, five (5) willow cultivars were selected for biomass yield. They were planted according to SRC (Short Rotation Coppice) protocol on four sites in Quebec (Canada) to determine their bioenergy potential in contrasting environments. Wood composition and anatomical traits were characterized and compared between both genotypes and environmental growing conditions. Tree height and stem diameter differed between sites, and pedoclimatic conditions more favorable for willow growth were identified. However, each cultivar showed a specific response to its environment. While no significant variation in lignin content was observed between sites, a clonal effect confirms the importance of cultivar selection. Surprisingly, the pattern of genotype variability in stem density was the same on all sites. Wood anatomy differed on fiber and vessel traits between high and low wood density sites, which suggests a probable effect of an abiotic stress. Furthermore, twice as many cellulose-rich G fibers were also found at the most dense site, evidence of potential for use in bioethanol production.

Os estudos da anatomia macro e microscópica do lenho como ferramenta auxiliar na taxonômia, sobretudo na identificação de espécies florestais, vêm sendo utilizados há décadas. A análise comparativa da estrutura anatômica do lenho permite a identificação de características morfológicas exclusivas das ordens, famílias, gêneros e, em muitos casos, de espécies, aumentando a gama de caracteres utilizados na descrição e identificação botânica de espécies arbóreas pela taxonomia clássica. No presente trabalho, foram utilizadas técnicas de análise comparativa e de descrição da estrutura anatômica macro e microscópica do lenho de árvores de espécies que ocorrem naturalmente na floresta tropical Amazônica nos municípios de Santarém, Mojú, Paragominas e Tailândia, no estado do Pará. Os objetivos do trabalho foram (i) caracterizar a estrutura anatômica macro e microscópica do lenho; (ii) identificar as características de valor taxonômico através de análise comparativa da estrutura anatômica do lenho; (iii) elaborar chaves de identificação das espécies pela estrutura anatômica macro e microscópica do lenho. Foram analisadas 100 amostras do lenho do tronco de árvores de 64 espécies, coletadas em 2004, pelo projeto Dendrogene/Embrapa Amazônia Oriental. A superfície das amostras do lenho foi polida com lixas e navalhas, seguindo-se a sua descrição macroscópica; lâminas histológicas do lenho foram preparadas com navalha de micrótomo de deslize, para a descrição microscópica do lenho. Os resultados possibilitaram, pela análise comparativa da estrutura anatômica do lenho, confeccionar as chaves de identificação macroscópica de 49 espécies dos 51 gêneros. Os gêneros Hymenolobium e Virola com 4 e 2 espécies, respectivamente, não puderam ser separados. A chave de identificação microscópica permitiu identificar 64 das espécies estudadas. A análise comparativa do lenho permitiu, da mesma forma, evidenciar 25 espécies com potencial para a dendrocronologia, sendo 10 e 15, com anéis de crescimento com distintos e pouco distintos, respectivamente. A aplicação da anatomia do lenho como importante ferramenta com potencial a taxonomia de espécies florestais é discutida no presente trabalho / Studies of macro and microscopic wood anatomy as an auxiliary tool in taxonomy, particularly in the identification of forest tree species, have been used for decades. Comparative analysis of the wood anatomical structure allows the identification of unique morphological characteristics of the orders, families, genera, and in many cases, species, increasing the range of characters used in the botanical description and identification of tree species by classical taxonomy. In this work, techniques were used for comparative analysis and description of the anatomical structure of macro and microscopic wood tree species, that occur naturally in the Amazon rainforest in the Santarém, Mojú Paragominas and Tailândia cities, in Pará State. The aims of the study were (i) to characterize the macro and microscopic anatomical wood structure, (ii) identify the characteristics of taxonomic value through a comparative analysis of the wood anatomical structure, (iii) prepare the keys for species identification by macroscopic and microscopic wood anatomical structure. Were analyzed 100 wood samples from 64 tree species collected in 2004, in the project Dendrogene/Embrapa Amazonia Oriental. The surface of wood samples was polished with sandpaper and knives, according to their macro description; histological wood sections were prepared with razor sliding microtome, for microscopic wood description. The results allowed for the comparative analysis of the anatomical wood structure, to produce the macroscopic identification keys to 49 species of 51 genera. The genera Hymenolobium and Virola species with 4 and 2, respectively, could not be separated. The results from comparative wood anatomy showed evidence of 25 tree species with high potential for dendrochronological studies in order to distinct tree-ring presence (10 species) and barely distinct tree-rings (15 species). The application of wood anatomy, as an important tool with the potential of forest species taxonomy is discussed in this paper.

Neste estudo analisamos a diversidade e endemismos da flora lenhosa das florestas estacionais decíduas (FEDs) do norte e centro do Perú. Caracterizamos a diversidade das plantas lenhosas ao longo dos vales, para definir os valores de conservação da área a nível nacional. Os resultados indicam que as FEDs do vale do Marañón apresentam valores significativamente altos em endemias em relação às outras FEDs do Perú e FEDs vizinhas e o padrão de endemismos e estrutura populacional das espécies variam no gradiente geográfico e altitudinal. Em constraste, as FEDs do vale do rio Tambo, centro do Perú, são moderadamente ricas em espécies do que a média das FEDs neotropicais e apresentam escassos endemismos. Esta região necessita de mais esforços de pesquisas para conhecer mais profundamente os elementos da biodiversidade. Neste estudo, também realizamos a caracterização dendro-anatômica do lenho das árvores de 87 espécies, sendo o primeiro registro da anatomia da madeira das árvores dos dois vales. Das análises do lenho das 183 espécies registradas nas florestas do norte e centro do Perú, só 157 apresentam anéis de crescimento e precisam ser analisadas em detalhe com outras pesquisas de desenvolvimento cambial e técnicas tradicionais de análises dendrocronológicas. A derivação desta informação pode alcançar alto impacto em estudos de variabilidade climática e aplicações na conservação. Assim mesmo, a análise preliminar dendrocronológica das taxas de crescimento do tronco revelam que as árvores de Cedrela kuelapensis apresentam as taxas de crescimento mais altas e ressaltam como um excelente recurso para programas de reflorestamento nos vales interandinos, além, das populações endêmicas de Cordia iguaguana e Esenbeckia cornuta são principalmente de exemplares jovens. Esperamos que as informações dos cinco capítulos constituam-se uma eficiente e importante ferramenta para melhorar a gestão dos recursos florestais dos vales estudados. / In this study we analyzed the diversity and endemism of the woody flora of Seazonally dry tropical forests (SDTF) in northern and central Peru. We characterized the diversity of woody plants along the valleys to define the conservation values of the area at the national and international levels. The results indicate that the SDTF s of the Marañón Valley show surprisingly high values in endemics in relation to other SDTF s in Peru and neighboring SDTFs, and the pattern of endemism and population structure of the species varies in geographic and altitudinal grades. In contrast, the SDTFs of the Tambo River Valley, central Peru, are moderately rich in species that average the neotropical SDTFs and have scarce endemism. This region needs more efforts to get to know the elements of biodiversity more deeply. In this study, we also performed the dendroanatomic characterization of 87 species and is the first report of the anatomy of the wood for the two valleys. From the analysis of the wood of the 183 species recorded in the forests of northern and central Peru, only 157 have growth rings and need to be analyzed in detail with other studies of exchange rate development and traditional techniques of dendrochronological analysis. The derivation of this information can reach high impact in studies of climatic variability and conservation applications. Likewise, the preliminary dendrochronological analysis of growth rates reveals that Cedrela kuelapensis showed the highest growth rates and stands out as an excellent resource for reforestation programs in the inter-Andean valleys, in addition, Cordia iguaguana and Esenbeckia cornuta endemic populations are mainly from young individuals. We hope that the information in the five chapters constitutes in efficient and important tool to improve the management of forest resources in the valleys studied.

Les arbres ont la capacité de percevoir des sollicitations mécaniques quotidiennes dues au vent et d’acclimater leur croissance et leur développement en conséquence. Ce stress mécanique se traduit essentiellement par des flexions des organes, en particulier des branches et de la tige. Des études antérieures ont montré que la croissance en diamètre du peuplier était stimulée en réponse aux flexions mimant l’effet du vent. Cette augmentation de la croissance s’accompagne d’une modification de la nature du bois mis en place, qui a pu être observé chez quelques conifères et angiospermes, et nommé « bois de flexion ». Mais la caractérisation anatomique de ce bois a été peu approfondie, et les acteurs moléculaires de sa formation n’ont jamais été recherchés. De plus, dans la plupart de ces études les sollicitations mécaniques appliquées à la tige sont des flexions multidirectionnelles et d’intensité non contrôlée. Or, la déformation étant la variable physique perçue par la plante, il est nécessaire de contrôler l’amplitude de la flexion appliquée à la tige. Grâce à un dispositif expérimental original, nous avons appliqué des flexions unidirectionnelles sur de jeunes tiges de peupliers tout en contrôlant l’intensité des déformations appliquées. Cette étude a montré que la perception des déformations s’effectuait à une échelle locale, conduisant à une ovalisation de la tige. Nous avons pu également différencier le bois formé sous des déformations en tension, que nous avons nommé Tensile Flexure Wood, du bois formé sous des déformations en compression, que nous avons nommé Compressive Flexure Wood. Les analyses anatomiques et moléculaires montrent que l’intensité des déformations en valeur absolue ne suffit pas à expliquer toutes les réponses et que le signe (tension ou compression) de ces déformations joue également un rôle. Chez des arbres stimulés par des flexions unidirectionnelles plus fréquentes, la croissance et la différenciation cellulaire sont modulés encore différemment, notamment dans la zone en compression, apportant à la tige un bénéfice adaptatif face aux sollicitations suivantes. Le gène CLE12.2 appartenant à la famille des gènes CLAVATA, gènes impliqués dans les régulations méristématiques, a été montré mécanosensible. Une approche de génomique fonctionnelle du gène CLE12.2 par l’utilisation de plants transgéniques présentant une sous- ou une surexpression du gène nous a permis d’émettre l’hypothèse d’une implication du peptide CLE12.2 dans la régulation des voies de biosynthèse de la paroi cellulaire. Cette étude a permis de mettre en avant la complexité des mécanismes moléculaires impliqués dans la formation du bois et apporte de nouvelles connaissances pour la poursuite des études sur l’acclimatation des arbres au vent. / Trees have the ability to perceive daily mechanical stresses related to wind and to acclimate their growth and development accordingly. Wind essentially results in organs bending, in particular in branches and stem. Previous studies have shown that growth diameter of poplar stem increased in response to bending; mimicking wind mechanical effect. This growth increment goes along with a change in the structure of the wood formed under bending stimulation. This type of reaction wood has been described for some conifers and angiosperms species, and was called "flexure wood". Until now, its anatomical characteristics have been poorly described, and the molecular actors of its formation have never been investigated. In addition, in most of these previous studies the mechanical stresses applied to the stem were bidirectional bendings with an uncontrolled intensity. Because mechanical strains constitute the physical variable perceived by the plant, it appeared necessary to carefully control the bending amplitude applied to the stem. Thanks to an original experimental setup, we applied unidirectional bendings on young poplar stems, while controlling its intensity. This study showed that the strains are perceived at a local scale and that the secondary growth response was also local, leading to stem ovalization. We also distinguished the wood formed under tension we named “Tensile Flexure Wood” from the wood formed under compression we named “Compressive Flexure Wood”. The anatomical and molecular analyzes show that the strain intensity in absolute value is not enough to explain all the answers and that the sign (tension or compression) of these strains also plays a role. In trees stimulated by more frequent unidirectional bendings, growth and cell differentiation are modulated even differently, especially in the area under compression, bringing to the stem an adaptive benefit to the following solicitations. The CLE12.2 gene, which belongs to the CLAVATA gene family involved in meristematic regulation, has been shown to be mechanosensitive. Functional analysis of the CLE12.2 gene in transgenic plants with under- or overexpression of the gene allowed us to hypothesize that the CLE12.2 peptide is involved in the regulation of the cell-wall biosynthesis pathways. This work highlighted the complexity of the molecular mechanisms involved in wood formation and brings new knowledge for further studies on trees acclimation to wind.

O crescimento e o desenvolvimento de ecossistemas florestais são fortemente influenciados pelas flutuações do clima. Sendo assim, espera-se que florestas de eucalipto de rápido crescimento sejam amplamente afetadas pelas mudanças climáticas. A utilização de métodos que possibilitem a avaliação e comparação dos atributos funcionais do xilema das árvores sob a dinâmica dos ciclos biogeoquímicos são necessários, a fim de antecipar e mitigar as consequências das mudanças climáticas no funcionamento das plantações. A análise do crescimento, anatomia, microdensidade e propriedades hidráulicas do xilema podem trazer importantes conhecimentos sobre a fisiologia das árvores. A avaliação dessas propriedades, contudo, ocorre geralmente em algumas regiões do xilema do tronco, ou ramos, sendo sua avaliação ao longo de todo o histórico das árvores um desafio. Assim, a relação entre as propriedades e atributos funcionais das árvores com os ciclos da água e do carbono no nível do ecossistema ainda não está claro. Em março de 2008, instalou-se em área localizada próxima do município de Itatinga-SP, a torre de fluxo do Projeto EucFlux. O projeto tem como objetivo avaliar os fluxos de carbono e água (eddy covariance) ao longo do crescimento e desenvolvimento de árvores de eucalipto. Isso, permite avaliar as dinâmicas biogeoquímicas sobre o ecossistema florestal, buscando predizer sua produtividade sob diferentes condições climáticas. Em novembro de 2009, mudas de Eucalyptus grandis foram plantadas na área experimental de 90 ha, sendo avaliadas (diâmetro, altura, volume, etc.) até maio de 2018 (final da rotação). Com o corte das árvores, uma análise retrospectiva das propriedades e atributos funcionais do xilema do tronco de árvores de E. grandis foi realizada. Buscando compreender as relações dessas propriedades com as variações inter-intranuais das variáveis climáticas e ciclos do carbono e da água registrados pela torre de fluxo. Os métodos, resultados e avanços do presente estudo são descritos em dois capítulos. No Capítulo I, utilizou-se amostras do lenho de Eucalyptus grandis, Tectona grandis e Cedrela fissilis, para a descrição de um protocolo para obtenção de cortes histológicos longos e seus potenciais usos para avaliação de anéis de crescimento de árvores de eucalipto e espécies arbóreas tropicais, em uma abordagem conjunta de anatomia microscópica, perfis de microdensidade e anatomia quantitativa. Para o Capítulo II, avaliou-se árvores de E. grandis, seus anéis de crescimento (classes dominantes e codominantes), relacionando o crescimento radial e as propriedades do lenho do seu tronco (anatomia e microdensidade conforme capítulo I) com os ciclos biogeoquímicos (torre de fluxo, eddy covariance) em um período de 8 anos e em resolução inter-intranual. Como também a relação da formação do xilema com o crescimento em altura das árvores no mesmo período e resolução. Observou-se diferenças significativas entre o crescimento e as propriedades do lenho das três classes de dominância, onde as dominantes, seguidas pelas codominantes e dominadas, apresentaram maiores dimensões e densidade do lenho. As variáveis climáticas e fluxos de carbono e água apresentaram forte correlação com as propriedades e atributos funcionais do lenho, onde maior temperatura média e disponibilidade de água, resultaram em maior crescimento do tronco, menor densidade do lenho e vasos de maior diâmetro e, assim, maior condutividade potencial do xilema. A evapotranspiração do ecossistema apresentou correlação significativa com todas as variáveis estudadas, sendo forte indício das flutuações das variáveis climáticas e, assim, regulador da formação do xilema e funcionamento das árvores. Observou-se correlação entre os fluxos de carbono e crescimento, onde valores mais negativos de C (maior sequestro) resultaram em maior crescimento. O evento de estresse hídrico de 2014 teve forte efeito sobre os ciclos do carbono e da água, alterando assim, as propriedades do lenho das árvores. Ainda, o crescimento em altura teve forte correlação com as propriedades do lenho, onde maior altura resultou em vasos de maior dimensão e, assim, um sistema hidráulico com maior potencial de condução, contudo, com maior risco de cavitação e falha hidráulica. Os resultados integrados apontam o forte potencial da utilização de cortes histológicos longos para espécies tropicais, aprimorando a delimitação das camadas de crescimento anuais e permitindo a quantificação de variáveis anatômicas em conjunto com perfis de microdensidade, fundamentais para estudos fisiológicos das árvores. Assim, a relação das propriedades do lenho, com as flutuações das variáveis climáticas e ciclos do carbono e da água ao longo de todo o histórico de uma rotação de eucalipto em resolução inter-intranual tornou-se possível, indicando importantes novas possibilidades para os estudos de dendrocronologia e ciências florestais. / Growth and development of forest ecosystems are strongly influenced by climate fluctuations. Thus, fast-growing eucalyptus forests are expected to be largely affected by climate change. The use of methods that allow the evaluation and comparison of the functional traits of the tree xylem under the dynamics of the biogeochemical cycles are necessary in order to anticipate and mitigate the consequences of climate change on the functioning of plantations. The analysis of the growth, anatomy, microdensity and hydraulic properties of the xylem can bring important knowledge about the physiology of the trees. The evaluation of these properties, however, usually occurs in some regions of the trunk xylem, or branches, and their evaluation throughout the entire tree history is a challenge. Thus, the relationship between the properties and functional traits of trees with water and carbon cycles at the ecosystem level is still unclear. In March 2008, the flux tower of the EucFlux Project was installed in an area located near of Itatinga-SP. The project aims to evaluate the flux of carbon and water (eddy covariance) along the growth and development of eucalyptus trees. This allows to evaluate the biogeochemical dynamics on the forest ecosystem, seeking to predict its productivity under different climate conditions. In November 2009, seedlings of Eucalyptus grandis were planted in the experimental area of 90 ha, being evaluated (diameter, height, volume, etc.) until May 2018 (end of rotation). With the cut of the trees, a retrospective analysis of the properties and functional traits of the trunk xylem of E. grandis trees was performed. Seeking to understand the relationships of these properties with inter and intra annual variations of the climate variables and cycles of carbon and water, recorded by flux tower. The methods, results and advances of the present study are described in two chapters. In Chapter I, samples of Eucalyptus grandis, Tectona grandis and Cedrela fissilis wood, were used to describe a protocol for obtaining long histological sections and their potential uses for evaluation of growth rings of eucalyptus trees and tropical tree species, in a joint approach of microscopic anatomy, microdensity profiles and quantitative wood anatomy. For Chapter II, it was evaluated E. grandis trees, their growth rings (dominant and codominant classes), relating the radial growth and the wood properties of their trunk (anatomy and microdensity according to chapter I) to the biogeochemical cycles (flux tower, eddy covariance) over a period of 8 years in inter and intra annual resolution. As also, the relation of the xylem formation with the growth in height of the trees in the same period and resolution. Significant differences were observed between growth and wood properties of the three dominance classes, where dominant, followed by codominant and dominated, had larger wood dimensions and density. The climate variables and carbon and water fluxes showed a strong correlation with the properties and functional attributes of the wood, where higher mean temperature and water availability resulted in higher trunk growth, lower wood density and larger diameter vessels, greater potential conductivity of the xylem. The evapotranspiration of the ecosystem showed a significant correlation with all the studied variables, being a strong indication of the climate variables fluctuations and, therefore, regulator of xylem formation and tree functioning. There was a correlation between carbon fluxes and growth, where more negative values of C (higher sequestration) resulted in higher growth. The water stress event of 2014 had a strong effect on the carbon and water cycles, thus altering the wood properties of the trees. Also, the growth in height had a strong correlation with the properties of the wood, where higher height resulted in larger vessels and, thus, a hydraulic system with greater potential of conduction, however, with greater risk of cavitation and hydraulic failure. The integrated results point to the strong potential of using long histological sections for tropical species, improving the delimitation of the annual growth layers and allowing the quantification of anatomical variables together with microdensity profiles, fundamental for physiological studies of the trees. Thus, the relationship of wood properties with fluctuations in climate variables and cycles of carbon and water throughout the history of an inter-intranasal eucalyptus rotation became possible, indicating important new possibilities for the studies dendrochronology and forest sciences.