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--- trabalhos:abstracts [2021/12/08 00:44]
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+++ trabalhos:abstracts [2021/12/08 01:28]
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 **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 ===

Laboratório de Ecologia de Florestas Tropicais

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