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Traços funcionais e estratégias ecológicas de espécies arbóreas em Floresta Ombrófila Mista no Planalto Catarinense / Functional traits and life-strategies of tree species Montane Araucaria Forest in Southern BrazilMissio, Francieli de Fátima 13 June 2014 (has links)
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Previous issue date: 2014-06-13 / The present study was conducted in a fragment of montane Araucaria Forest, from southern Brazil. The first chapter aimed to describe functional traits (wood density, leaf size, regime of leaf renovation, dispersion syndrome and maximum height) for tree species and to group them functionally. The second chapter sought to evaluate the relationships among functional traits (wood density, leaf size and maximum height), demographic rates and environmental gradients. For this sake, the 20 most abundant species in the fragment were selected, sampling for each species a total of 10 individuals, in order to determine the wood density and leaf size. Information about leaf renovation regime, dispersal syndrome and maximum height were obtained through field observation and literature review. Data of abundance, demographic rates from 2008 and 2012, and environmental characterization were obtained from the Database of Laboratory of Dendrology and Phytosociology (LABDENDRO), of the Santa Catarina State University. The data for this area were collected within 50, 100 m2, plots, totaling 1 ha of sampling area. The species were grouped according to their functional traits, by a dendrogram, using Ward algorithm. For the analyzes of the relationship between functional traits and demographic rates, the species were ordered through a Non-metric Multidimensional Scaling (NMDS), in which the demographic rates were fitted a posteriori to the ordination, being those significant (p ≤ 0,10) plotted as vectors. The response of function traits to environmental gradients was verified through a Redundancy Analysis (RDA), using a community weight matrix of functional traits (CWM) and environmental data. The dendrogram indicated
the existence of two main groups of species, formed due to foliar renovation regime, with subsequent subdivisions in function of leaf size and dispersal syndrome. The species with greatest values of wood density and short maximum height showed more elevated values of recruitment, increment of population abundance and basal area turnover. The species with greatest values of diametric increment were those with higher maximum height and lower values of wood density. In sites with basic soils, the community demonstrated greater values of wood density. Plots with more elevated values of soil Mg content and lower altitude predominantly showed large trees, with larger leaf size. We conclude that the community was organized in functional groups, with distinct life strategies, as demonstrated by species performance along 2008 and 2012. Furthermore, the functional traits were influenced by environmental gradients, indicating a short space turnover / O presente estudo foi realizado em um fragmento de Floresta Ombrófila Mista Montana, localizado em Lages, SC. O primeiro capítulo teve como objetivo descrever os traços funcionais (densidade da madeira, tamanho da folha, regime de renovação foliar, síndrome de dispersão de propágulos e altura máxima) das espécies arbóreas e agrupá-las funcionalmente. O segundo capítulo teve como objetivo avaliar as relações entre os traços funcionais (densidade da madeira, tamanho da folha e altura máxima), taxas demográficas das espécies arbóreas e gradientes ambientais. Para isto, foram selecionadas as 20 espécies mais abundantes do fragmento, amostrando um total de 10 indivíduos, e determinado a média, por espécie, da densidade básica da madeira e do tamanho das folhas. Informações sobre o regime de renovação foliar, síndrome de dispersão de propágulos e altura máxima foram obtidos por meio de observações de campo e revisão de literatura. Os dados de abundância da comunidade, as taxas demográficas para o período de 2008 a 2012 e a caracterização ambiental foram obtidas a partir do banco de dados do Laboratório de Dendrologia e Fitossociologia (LABDENDRO), da Universidade do Estado de Santa Catarina. Esses dados foram coletados a partir de 50 parcelas alocadas no fragmento, de 10 x 20m, totalizando 1 ha de área amostrada. As espécies foram agrupadas de acordo com seus traços funcionais, em um dendrograma, construído por meio do algoritmo de Ward. Para a análise da relação entre os traços funcionais e as taxas demográficas, as espécies foram ordenadas por meio de um Escalonamento Multidimensional Não-métrico (NMDS), onde as
taxas demográficas foram ajustadas a posteriori a ordenação, sendo aquelas significativas (p ≤ 0,10) plotadas na forma de vetores. A relação dos traços funcionais em resposta aos gradientes ambientais foi verifica por meio de uma análise de redundância (RDA), utilizando uma matriz de traços funcionais ponderada para a comunidade (CWM) e de dados ambientais. O dendrograma indicou a existência de dois grandes grupos de espécies, formados em função do regime de renovação foliar e com subdivisões subsequentes devido ao tamanho das folhas e à síndrome de dispersão. Espécies com maiores valores em densidade básica da madeira e menor altura máxima apresentaram elevado recrutamento, elevada mudança líquida positiva em número de indivíduos e rotatividade em área basal. As espécies com maiores valores em incremento diamétrico foram aquelas com maiores valores de altura máxima e menor densidade básica da madeira. Em solos mais básicos a comunidade apresentou maiores valores em densidade básica da madeira. Os locais com maiores teores de Mg e com menor altitude apresentaram predominantemente maior porte das árvores e maiores tamanhos de folha. Conclui-se que a comunidade avaliada apresenta-se organizada em grupos funcionais, com estratégias de vida distintas, como indicado pela performance das espécies ao longo do período de 2008 a 2012. Além disso, os traços funcionais foram influenciados pelos gradientes ambientais, demonstrando rotatividade dos mesmos em pequena escala espacial
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Dinâmica da vegetação de um fragmento de mata atlântica nordestina.RABELO, Felipe Rodrigo de Carvalho 30 March 2012 (has links)
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Previous issue date: 2012-03-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Data are presented for 2004, 2007 and 2010 on physiognomy, dynamics, diversity, species composition and density of the wood plant canopy (CA with CBH> 15 cm) and understory (UN, with a circumference at ground level between > 3cm and CAP <15cm) in a gradient edge-interior formed at 35 years in an Atlantic Forest fragment, Igarassu, PE. In 2004, three environments were evaluated: edge (0-50m), intermediate (50-100m) and interior (more than 150m from the tree line), and analyzed by environment of 1000 m², divided into plots of 10 × 10m, to measure the CA individuals. In each plot was plotted a subplot of 5 × 5m for the UN sample. In 2010 branches were collected from three adult individuals of the species for the collection of sample disks. The number of individuals (NI), basal area (BA) and demographic rates in the three environments the CA showed no edge effect or if there was, since the edge is sealed. In UN the edge had lower values of NI and BA demographic rates and higher than the inside. Differences between strata occur, regardless of sealing the border, as the young plants that are still in UN are more sensitive than the trees of the CA, the changes caused by the creation of the border. Rates of loss and gain of BA and BA rotation in NI and UN showed higher values than in the CA, which points to a stratum with major changes. In CA there were no differences in species richness between environments, distinct from that observed in UN. The composition in CA environments closer to the tree line were very similar and distinct from the interior, indicating that there has been no recovery in all environments while the composition of the UN had low similarity. The edges of CA and UN showed higher concentration of individuals at intervals of class values lower density wood. It can be concluded that the CA has regained biomass, although the edge and have not recovered to intermediate composition. The UN also suffer from edge effect. If we consider that the environment had more edge classes of individuals in wood density of less value and that there is an inverse relationship between wood density and mortality rates / annual periodic increment in diameter can be assumed that the different composition of the edge would be result of the increased mortality of species of lower density wood. / São apresentados dados de 2004, 2007 e 2010 sobre fisionomia, dinâmica, diversidade, composição de espécies e densidade da madeira de plantas do dossel (DO, com CAP > 15cm), e sub-bosque (SB, com circunferência ao nível do solo entre > 3cm e CAP < 15cm) em um gradiente borda-interior formado a 35 anos em um fragmento de Mata Atlântica, Igarassu, PE. Em 2004, foram avaliados três ambientes: borda (0-50m), intermediário (50-100m) e interior (mais de 150m do limite florestal), sendo analisados 1000 m² por ambiente, divididos em parcelas de 10×10m, para medir os indivíduos do DO. Em cada parcela foi plotada uma sub-parcela de 5×5m para amostragem do SB. Em 2010 foram recolhidos ramos de três indivíduos adultos das espécies, para coleta de discos amostrais. O número de indivíduos (NI), área basal (AB) e taxas demográficas no DO dos três ambientes mostraram que não houve efeito de borda ou se houve, a borda já estaria selada. No SB a borda teve menores valores de NI e AB e maiores taxas demográficas que o interior. Diferenças entre os estratos acontecem, independente do selamento da borda, já plantas jovens do DO que ainda estão no SB são mais sensíveis que as árvores do DO, as mudanças causadas pela criação da borda. Taxas de perda e ganho de AB e de rotatividade em NI e AB no SB apresentaram valores maiores que no DO, o que aponta para um estrato com maiores mudanças. No DO não ocorreram diferenças de riqueza de espécies entre os ambientes, distinto do observado no SB. A composição no DO nos ambientes mais próximos ao limite florestal foram bastante similares e distintos do interior, indicando que ainda não houve recuperação da composição enquanto todos os ambientes do SB tiveram baixa similaridade. As bordas do DO e SB apresentaram maior concentração de indivíduos em intervalos de classe de menores valores de densidade de madeira. Pode-se concluir que o DO já recuperou a biomassa, embora os ambientes de borda e intermediário não tenham recuperado a composição de espécies. O SB ainda sofrer efeito de borda. Se considerarmos que o ambiente de borda teve mais indivíduos em classes de densidade da madeira de menor valor e que há uma relação inversa entre densidade da madeira e taxas de mortalidade/incremento periódico anual em diâmetro pode-se supor que a composição diferenciada da borda seria resultado da maior mortalidade de espécies de menor densidade da madeira.
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The Influence of sociality on population dynamics in the Alpine Marmot / Influence de la socialité sur la dynamique de population chez la marmotte alpineDupont, Pierre 26 January 2017 (has links)
La dynamique des populations peut être définie comme l'étude des forces responsables de la taille et de la structure d'une population. Plusieurs facteurs influençant la dynamique des populations ont déjà été identifiés. Ces facteurs peuvent être classés de par leur niveau d'influence, d'une influence à l'échelle de la population toute entière, comme par exemple les changements climatiques ou la densité de population, jusqu'à des facteurs individuels comme l'âge ou le sexe. Récemment, de nombreuses études ont insisté sur l'importance de la structure en âge pour cette dynamique.Chez les espèces sociales, un niveau supplémentaire de structuration de la population est le groupe. Cependant,les conséquences de cette structuration en groupes sociaux est encore mal connue.Au cours de ma thèse, j'ai tenté de répondre a cette question de différentes manières. J'ai tout d'abord étudié comment les paramètres démographiques individuels étaient influencés par la taille et la composition du groupe. J'ai pu notamment mettre en évidence un effet négatif du nombre de juvéniles femelles présent lors du développement sur la probabilité de devenir dominant une fois à l'age adulte. Dans une deuxième temps, j'ai étudié l'importance des interactions entre groupes en quantifiant l'impact d'un changement de dominant sur la dispersion des subordonnés. Enfin, j'ai également quantifié l'influence des différents groupes au sein de la population démontrant que les grands groupes contribuent relativement moins au taux de croissance de la population. Ces différents résultats sont ensuite discuté dans un cadre de démographie évolutive et de nouvelles pistes de recherche sont proposées / Population dynamics can be defined as the study of the forces responsible for the size and structure of a population. Several factors influencing population dynamics have already been identified. These factors can be categorized according to their level of influence. Some factors have a population-wide influence, such as climate change or population density, while others affect the individual level such as age or sex. Recently, many studies have emphasized the importance of this age structure for population dynamics.In social species, an additional level of structuring of the population is the group. However, the consequences of this social group structuring are still poorly understood.In this thesis, I try to answer this question in different ways. I first studied how the individual demographic parameters were influenced by the size and composition of the group. I was able to highlight in particular a negative effect of the number of juvenile females present during development on the probability of becoming dominant once in adulthood. In a second step, I studied the importance of interactions between groups by quantifying the impact of a change of dominant on the dispersion of subordinates. Finally, I also quantified the influence of different groups within the population showing that large groups contribute relatively less to the population growth rate. These various results are then discussed in a context of evolutionary demography and new avenues of research are proposed
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Consistency of demographic trade-offs across 13 (sub)tropical forestsKambach, Stephan, Condit, Richard, Aguilar, Salomon, Bruelheide, Helge, Bunyavejchewin, Sarayudh, Chang-Yang, Chia-Hao, Chen, Yu-Yun, Chuyong, George, Davies, Stuart J., Ediriweera, Sisira, Ewango, Corneille E.N., Fernando, Edwino S., Gunatilleke, Nimal, Gunatilleke, Savitri, Hubbell, Stephen P., Itoh, Akira, Kenfack, David, Kiratiprayoon, Somboon, Lin, Yi-Ching, Makana, Jean-Remy, Mohamad, Mohizah Bt., Pongpattananurak, Nantachai, Perez, Rolando, Rodriguez, Lillian Jennifer V., Sun, I-Fang, Tan, Sylvester, Thomas, Duncan, Thompson, Jill, Uriarte, Maria, Valencia, Renato, Wirth, Christian, Wright, S. Joseph, Wu, Shu-Hui, Yamakura, Takuo, Yao, Tze Leong, Zimmerman, Jess, Rüger, Nadja 04 January 2024 (has links)
1. Organisms of all species must balance their allocation to growth, survival and
recruitment. Among tree species, evolution has resulted in different life-history
strategies for partitioning resources to these key demographic processes.Life-history strategies in tropical forests have often been shown to align along
a trade-off between fast growth and high survival, that is, the well-known
fast–slow continuum. In addition, an orthogonal trade-off has been proposed
between tall stature—resulting from fast growth and high survival— and recruit-
ment success, that is, a stature−recruitment trade-off. However, it is not clear
whether these two independent dimensions of life-history variation structure
tropical forests worldwide.
2. We used data from 13 large-scale and long-term tropical forest monitoring plots
in three continents to explore the principal trade-offs in annual growth, sur-
vival and recruitment as well as tree stature. These forests included relatively
undisturbed forests as well as typhoon-disturbed forests. Life-history variation
in 12 forests was structured by two orthogonal trade-offs, the growth−survival
trade-off and the stature−recruitment trade- off. Pairwise Procrustes analysis
revealed a high similarity of demographic relationships among forests. The small
deviations were related to differences between African and Asian plots.
3. Synthesis. The fast–slow continuum and tree stature are two independent di-
mensions structuring many, but not all tropical tree communities. Our discovery
of the consistency of demographic trade-offs and life-history strategies across
different forest types from three continents substantially improves our ability to
predict tropical forest dynamics worldwide.
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