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--- trabalhos:abstracts [2021/05/27 01:18]
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+++ trabalhos:abstracts [2021/12/08 01:28]
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-==== Teses de Doutorado ====
+=====Teses de Doutorado=====
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 **Abstract:** One of the greatest challenges of ecology is to understand and predict the fluctuations in the biological populations. When we consider the human intervention in this understanding, we can, at the same time, make predictions about the future of the populations and understand better their natural processes of regulation and control. In this work we carried out a study about the ecology of populations of two shade tolerant tree species (Guapira opposita (Vell.) Reitz, that occupies the canopy and Rudgea jasminoides (Cham.) Müll.Arg., that occupies the understory) to answer the question of how the structure, population dynamics and seedling performance respond to environmental heterogeneity caused by disturbances related with fragmentation and secondary succession. In the first chapter we tested if the population structure, measured by size distributions, is related to the size and/or to the successional stage of the fragment. From the conclusions generated in this first study, in the second chapter we evaluated if population dynamics parameters, such as asymptotic growth rate and vital rates explain the variation in density and structure. In the third chapter we tested if the seedling performance of these species is affected by canopy openness and litter depth, which are known promoters of environmental heterogeneity in secondary forest fragments. In order to achieve this goal we marked and followed by two years (2007- 2009) populations of both species in six secondary forest fragments of different successional stages in the Southeast Atlantic Plateau. Regarding the population structure, Guapira showed variation associated to the degree of forest structuring, while for Rudgea the fragment size was the most important explanatory variable, what lead us to hypothesize that Rudgea is in risk of local extinction in the medium fragments. Regarding the analysis of population dynamics, Rudgea showed a population doubling time in the medium fragments 4.5 times greater than in the large ones, what lead us to conclude that this risk of local extinction can be mitigated or even reversed. For Guapira, the rates did not differ between the successional stages, being predicted stable populations in both (955;8776;1). The analysis of the effect of the canopy openness and the litter depth in the seedling performance showed the importance of the interaction between these factors and the relevance of considering the different seedling ontogenetic stages. Through a new approach, we demonstrated how important is to consider complementary studies (structure and dynamics) in order to really understand what happens at population level. Besides, we highlight the importance of studies with dynamics in order to elucidate the demographic mechanisms that occur in each population. This knowledge is a fundamental tool for planning more directional management and conservation actions.
-==== Dissertações de Mestrado ====
+=====Dissertações de Mestrado=====
+=== BEL, Renan Lucas Siena Del ===
+**Tree recruitment in a restinga rainforest: Influence of functional neighborhood and soil**
+**Abstract:** While biological communities are complex systems in which numerous mechanisms act in different scales and different processes can generate the same pattern, one way to answer questions regarding the assembly of plant communities is to find correlations between environmental patterns indicative of underlying niche processes with the emerging patterns of a community. Because of that, it is essential to keep developing our understanding on how to represent the niche processes and how to better assess the community structure. In this dissertation we investigate how different environmental variables contribute to our understanding of niche processes. In particular, we are interested in how variables of biotic or abiotic nature interact and contribute to the pattern observed in the structure of the community, and whether the integration of these components is important in identifying the processes involved in community assembly. We use the spatially explicit leaf traits distribution of young (recruited in the last 10 years) individuals from a restinga in Ilha do Cardoso to represent the resulting pattern of the assembly processes, as well as data collected in 2009, to rebuild the neighborhood in which these individuals were recruited. We found that different combinations of biotic and abiotic variables explain different leaf traits distributions, but when we include the young individuals species as a random factor in our models, our results point for no correlation between environmental variables and leaf traits. Because of these conflicting results we infer that while both biotic and abiotic variables work together as predictors of the structure of the community, they do so via species distribution, which is in turn, correlated to an individual's leaf traits values. Thus, environmental variables are only informative when we have no information about the identity of the species. Based on our results, we propose that both types of variables (biotic and abiotic) must be used together when trying to assess the niche processes in a community, as both may be complementary and sometimes interact to form a more complete picture. Together our results open some lines of investigation that may further our knowledge over the mechanisms behind the tree community assembly and may inform future work in the field in order to achieve a better resolution in structure analyses.
 === SOUZA, Luanne Caires da Cruz ===
@@ Linha 251: / Linha 256: @@
 larger CBH The sampling units were not grouped within the same condition. Anetium
 citrifolium was an indicator species of the interior of fragments in the pastures matrix.
+=== SALLES, Maysa da Costa Lima ===
+**Linear edge effects of different ages on the composition and structure of the shrub-tree community in the Atlantic Forest**
+**Abstract:** Forest fragmentation reduces the total area covered by the forest and exposes the plant
+community to edge effects, even if the edge is a linear opening. Beside, environmental
+factors associated to disturbances, such as fragmentation and topographical features, are
+some of the factors that determine community change. Hence, the aim of this study
+consisted in evaluating the effects of linear edges with different ages (30 and 200 years)
+of and the influence of environmental factors associated with them on the plant
+community of two forest layers of an Atlantic rainforest area located in the state of Rio
+de Janeiro, Brazil. Data concerning community structure and composition were
+compared between the different locations within the studied area, from which both slope
+and altitudinal interactions were evaluated. We suggested that the plant community of
+the Tinguá Reserve is under edge effects, but that these are less intense given that the
+impacts have been buffered by the formation, along the years, of a secondary vegetation
+layer, associated with an adjacent forest matrix and the absence of stochastic events.
+The older edge (200 years) had a lower richness and a different plant composition from
+the others locations. It suggests that the tree and shrub community may be under the
+influence of permanent damages from edge effects. The more recent edge (30 years)
+could be in a period of transition which the early successional trees, that reproduced
+immediately after the edge creation may reach the adult stage, near by the other tree
+species, and they constitute the upper stratum of the forest. The altitudinal and slope
+variables influence in some way the floristic composition, but other associated variables
+must be considered for a more precise evaluation.
 === PANNUTI, Márcia Ione da Rocha ===
@@ Linha 272: / Linha 303: @@
 **Abstract:** Composition is an important indicator of functional patterns of ecosystems, as it controls basic processes related to the availability of nutrients and to ecosystem productivity. Climatic and edaphic conditions and the quality of the litter and soil fauna as determining factors are of particular importance in the process of decomposition. The significance of each one of these varies with spatial and temporal scale. The objective of this work was to evaluate the importance of certain determining factors of decomposition in sites representing the main forest ecosystems of the state of São Paulo, Brazil. To accomplish this, two independent experiments were conducted. The first, denoted here as the Exotics experiment, was to examine the effects of the type of forest and the soil fauna on the decomposition of leaves of an exotic species (//Laurus nobilis L.//) in two humid forests (Restinga Forest of the Parque Estadual da Ilha do Cardoso e Atlantic Forest of the Parque Estadual Carlos Botelho) and a seasonal forest (Semideciduous Forest of the Estação Ecológica de Caetetus). The effects of these factors were tested above and belowground, to simulate the environment of decomposition among leaves and roots respectively. The type of forest had a significant effect over fauna above the surface, while below the surface, only fauna had significant effect. These results indicate that the hierarchy of determining factors in decomposition differs between leaves and roots. If on the one hand decomposition in leaves is much more susceptible to variation in climate than are roots, on the other hand changes in the soil fauna affect decomposition in both environments. Above the surface, fauna had a significant effect only in the Atlantic Forest, emphasizing the difference between two humid forests. Under the surface, and in the absence of fauna, the percentage of remaining biomass was very similar in the three forests. Notwithstanding differences in the forests, the presence of fauna was apparent, suggesting that there is a specific contribution of fauna in decomposition among roots in these forests. The Restinga Forest produced the most pronounced effect of fauna below the soil surface. These results indicate that fauna is a factor of notable importance in the decomposition of roots, especially in humid sandy tropical forests. The other experiment, here called the Native experiment, was developed to evaluate the effects of the substrate and the forest type on the decomposition of leaves of four native species in sites of the four major forest types in São Paulo state. The experiment was conducted in the same three forest sites as the Exotics experiment, including the Cerradão da Estação Ecológica de Assis. A tree species was chosen in each forest type, the leaves of which were used as substrate for the litter bags. The type of forest and the substrate demonstrated a significantly greater effect on the quantity of remaining mass throughout the experiment. The majority of the species suffered greater losses in the Atlantic Forest, followed by the Restinga Forest, the Semideciduous Forest, and the Cerradão. These results suggest that the total associated precipitation and its distribution are important determinants in the process of decomposition. As such, the two most humid forests show, on average, decomposition rates twice as great as the two seasonal forests. The rest of the differences encountered between forest types can be explained by edaphic and biotic factors. With respect to the effect of the species, the greatest biomass losses were observed in //Esenbeckia leiocarpa Engl.//, followed by //Copaifera langsdorfii Desf.//, //Guapira opposita Vell.// and //Calophyllum brasiliensis Camb.// Chemical parameters only show significant negative correlation with decomposition rates when G. opposita is excluded from the analysis. In this case the percentage of lignin was the parameter that showed the greatest correlation (r2= 0,59). In spite of the general patterns presented above, the interaction between forest type and substrate showed some variation, principally related to the loss of mass of C. langsdorfii in its native habitat, the Cerradão. Comparing decomposition rates (k) found in the Semideciduous Forest and Cerradão, //C. langsdorfii// shows a decrease of 40% more in the Cerradão, while the other species show, on average rates 28% lower in the Cerradão than in the Semideciduous Forest. These results suggest a strict correlation between the decomposition community and the local litter. Understanding processes of decomposition, is of fundamental importance and includes recognizing the determining factors and the variation in the importance of these factors under different environmental conditions, as presented in this study. This is true not only for our understanding of the forest ecosystems of São Paulo, but also for management planning, restoration, and conservation.
+=====Monografias (Iniciação Científica e trabalhos de conclusão de graduação)=====
+=== AULER, Jennifer Prestes ===
+**Environmental heterogeneity and the spatial distribution of Amazonia's trees**
+**Abstract:** Niche and dispersal limitation are important coexistence mechanisms that can spatially structure tree communities. We aimed to verify the influence of environmental heterogeneity in the relative importance of those processes. We used data from ForestGEO plots with different environmental heterogeneity (Colombia-CO < Brazil-BR < Ecuador-EQ). We selected the most plausible of four concurrent spatial models: Randomness (CSR), Niche (NH), Dispersal Limitation (DL), and both (NH+DL). BR e EQ didn't diverge in the probability of model selection, having 85,6% and 83% of niche models selected (NH and NH+DL), while in CO only 57,5% were observed. The proportion of no model selected was four times higher in CO than in BR and EQ. We attribute these differences to CO's lesser environmental heterogeneity and conclude that it influences the relative importance of processes. Plots with a higher proportion of coexistence mechanisms are also significantly more diverse (BR and EQ > CO).
+=== ROSA, Matheus Guthierris Bitencourt ===
+**Phylogenetic structure of seedling communities in Restinga forests with different environmental conditions**
+**Abstract:** Ecological communities often differ in species richness, composition and abundance,
+reflecting different assembly processes. Niche-determined processes and neutral
+processes may interact in the role of structuring different communities. Assessing the
+phylogenetic structure of communities should allow us to infer niche-related
+processes with respect to neutral processes, if the phylogenetic distances between
+co-ocurring species reflects niche differences. On one hand, if species tolerance to
+abiotic conditions are phyllogenetically conserved, intense environmental filtering is
+expected to promote community assemblages more phyllogenetically related than
+chance. On the other hand, negative interactions between neighbouring species can
+limit niche similarity in local assembly, if species interactions, such as competition for
+limited resources, is stronger between species that share the niche of a common
+ancestor. In the stage of seedlings, competition may not be able to impose a non-
+random signal on the phylogenetic structure of the entire habitat, but it may drive the
+assembly of local neighbourhoods. We therefore intend to infer the relative
+importance of different assembly processes by comparing the phylogenetic structure
+of seedlings communities in different Restinga forest physiognomies from the Parque
+Estadual da Ilha do Cardoso (Restinga Alta Alagada - RAA, Restinga Alta Drenada -
+RAD e Restinga Baixa – RB), at the scale of the entire habitat and the scale of local
+neighbourhoods. We describe phylogenetic structure of the entire habitat and local
+neighborhoods by calculating the mean pairwise phylogenetic distances between co-
+occuring species, both weighted and unweighted by species abundances. At the
+scale of the entire habitat, we ask if species composition at each forest type differs
+from null expectations, we test this by comparing the observed MPD value for each
+Restinga forest with a null distribution of communities generated by drawing species
+by chance from an adult tree species pool. We found that different Restinga forests
+show random phylogenetic structure at this scale. And, at the scale of local
+neighbourhoods, we ask if the distribution of MPD per triad differs between Restinga
+forests physiognomies, by comparing the F statistics from a simple Analysis of
+Variance with the distribution of F generated by permutations of MPD between
+habitats. We then conducted a post-hoc test to evaluate the absolute differences
+between groups of neighbourhoods in different Restinga forest types. We found that
+the distribution of MPD per triad in Restinga Baixa differs from the distribution of both
+Restinga Alta forests, but the Restinga Alta Alagada (flooded habitat) and Restinga
+Alta Drenada (drained habitat) don’t differ from each other. Our results therefore
+suggest that neutral processes are more important than niche processes to
+determine the assembly of seedlings communities at the entire habitat scale,
+however, niche-related processes, such as habitat filtering and competition may have
+a secondary role by determining local differences in the phylogenetic structure of
+neighbouring species.
+=== MORETTO, Felipe Alexandre ===
+**Natural regeneration and seedling diversity in a coastal plain transition ecosystem - hillside**
+**Abstract:** The seedling community of coastal plains of Caraguatatuba county was studied in a
+fragment of 50 acres of Forest Transition Restinga - Hill. The study area has been
+described by means of 40 sets of three plots of 1m x1m totaling an area of 120m2,
+with 23 sets were flooded condition and 17 in non-flooded conditions (drought). We
+obtained canopy opening with the help of Densiometer. In total 507 seedlings were
+identified, representing an average of 4.23 seedlings per m2. It was possible to
+observe a high richness, with 82 different species. The most abundant species were
+//Calypthrantes sp// (107), //Myrta sp1// (82) and //Annona cf reticulata cf// (19). The family
+Myrtaceae showed the highest species richness, totaling 18 species. The flooded
+plots had on average 9.99 seedlings per 3m 2 and droughts 15.69 per 3m 2. The
+average number of species in the wetlands was 3.69 species per 3m 2 and in the dry
+plots was 6.11 seedlings per 3m 2. The predictions of this study were that the
+wetlands should contain fewer species and lower species richness compared to
+areas not flooded. For canopy opening was expected that more open areas possess
+greater number of seedlings and greater species richness. However after
+randomization of data was not possible to observe that wetlands had less wealth and
+fewer species (p = .33). Increasing the percentage of canopy openness did not
+significantly affect the number of seedlings (p = 0.23) or species richness (p = .44).
+Thus, the results indicate that environmental variables are not sufficient to explain the
+observed variation in abundance and species richness of seedlings in this
+ecosystem. However other factors may be limiting for seedling establishment. Among
+the possible factors, the human disturbance area for removal of palm (Euterpe
+edulis), the large number of paths traced in the region (trampling seedlings) and
+competition from herbaceous plants deserve more detailed studies in the future.
+=== DIAS, Julia de Freitas ===
+**Survey of Seedling Production of Restinga Species in Nurseries State of São Paulo: Implications for ecological restoration**
+**Resumo:** To be viable to carry out restoration projects following the scientific statements and
+legislation is essential that there is availability of seedlings in nurseries with high species and
+genetic diversity. In order to evaluate the current availability of seedlings, production capacity
+and the main constraints to the production of a high diversity of restinga (white sand coastal
+vegetation) species, a study was conducted with nurseries producing seedlings of restinga
+species in the state of São Paulo. In total, 122 nurseries and 41 counties were contacted,
+resulting in only six nurseries producing seedlings from areas of restinga. The definition of
+the profile of resting seedlings production in these six nurseries was done through
+questionnaires technical and administrative. Among the main results of this survey, we can
+highlight the small number of seedlings of restinga species produced by the north coast
+nurseries, the difficulties in obtaining seeds mainly related to the process of seed collection,
+the disarticulation of the sectors involved in the production of seedlings of restinga species,
+the tiny share of the municipalities in seedling production and the perception of the producers
+of changes in the fruit phenology of the restinga species in their collection areas. This study
+highlights the current shortage of seedling of restinga species and should be useful as a tool to
+reveal the nurseries working in this ecosystem, and to improve the contact between them and
+the restoration planning groups.
+=== PEREIRA, Thiago ===
+**Effects of light quality on seed germination of Myrtaceae species from restinga of Cardoso Island**
+**Abstract:** The Myrtaceae family is one of the most ecologically important families, mainly in the Atlantic forest, being the dominant family in diverse tropical forests. Specifically in 3restinga" (coastal sandy plains) areas, Myrtaceae is noted for high species richness, being among the trees, often the most diverse. However there are few studies about the ecology and physiology of this family. Knowledge about the conditions for seed germination, in the case of Myrtaceae species, may increase the success in producing of seedlings in nurseries for use in forest restoration The analysis of light requirements for germination of the Myrtaceae species provides data that can be useful both in evolutionary studies about the family Myrtaceae, as to indicate the correct phase of succession to use of these species of Myrtaceae occurring in the Ilha do Cardoso in restoration projects in tropical areas. The germination of seeds of three species, //Eugenia umbelliflora//, //Myrcia multiflora// and //Blepharocalyx salicifolius//, were analyzed in a white light treatment and in the control (dark). An analysis of seed germination under distinct Red/Far red ratios was also performed for the species //Eugenia umbelliflora//. The seeds of the three species germinated in the presence of light and in the dark, indicating that the seeds have great environmental plasticity about light and can occupy different habitats. //E. umbelliflora// and //B. salicifolius// probably have their germination controlled by phytochrome A (phyA), using a Very Low Fluence Response (VLFR). The species //M. multiflora// show a higher germination rate under white light, which could indicates positive photoblastic seeds, but this classification requires complementary studies. Tests at different levels of R / FR for //E. umbelliflora// reinforce that this species has wide environmental plasticity, with the ability to germinate both in treefall gaps and under the canopy.
+=== PEREIRA, Nathália Helena Azevedo ===
+**Spatial distribution of terrestrial tank bromeliads in restinga: causes and consequences**
+**Abstract:** The plants’ spatial distribution pattern is the result of biotic and abiotic factors, from space
+competition to nutrients, light and water availability. To analyze the factors that vary spatially, light incidence and edaphic characteristics for example, is key to comprehend the influence they could have over the space distribution of the vegetation species in natural environments. This study aimed to analyze the possible factors that determine the distribution of terrestrial bromeliads, a group of plants that is very abundant in restinga, dominating the herbaceous layer on large tracts. On the other hand, the presence of bromeliads in the herbaceous layer can hinder the establishment of arboreal species and affect the vegetation structure. Thus, the consequences of the presence of bromeliads over the vegetation structure were also analyzed in this study. The study was conducted in a patch of restinga forest, at the “Parque Estadual da Ilha do Cardoso”, south coast of São Paulo state. Were sampled 5,76 ha, in 144 contiguous shares of 20 x 20m, in wich was registered the total number of rosettes of terrestrial bromeliads, as well as the percentage of coverage of the ground of each species. Were found seven terrestrial bromeliads species: //Bromelia antiacantha//, //Canistrum cyanthiforme//, //Nidularium innocentii//, //Nidularium procerum//, //Quesnelia arvensis//, //Vriesea carinata// e //Vriesea ensiformis//, and about 50% dos 5,76ha of the forest of restinga sampled were covered by bromeliads. The species that presented the greatest number of rosetas and the biggest coverage area were //N. procerum//, //N. innocentii// e //C. cyanthiforme//. The results indicate that the terrestrial bromeliads distribution is positively related with the canopy opening and that the growing of the porcentage of thick sand between 5 and 20m underground is related to the decrease of the number of bromeliads per share. The variety of individual arboreal adults decreased with the rising of the number of rosetas on a share. It wasn't noticed any relationship between the presence of bromeliads and the abundance of adult arboreal species on the shares, what suggests that the bromeliad don't interfere the structure of the forests dossel and seems to be using other space than the ocuppied by the arboreal species.

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