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Plant functional traits have been recognized as important factors related to the ecological strategies of species in forest ecosystems. We examined the relationships between functional traits and both tree species performance and environmental conditions in a subtropical forest in Brazil. Over four years (2008-2012), we investigated how demographic rates were related to functional traits (wood density, leaf area and tree height) of 20 species sampled within 50 plots of 10 × 20 m, which had previously evaluated as to environmental conditions. Non-metric multidimensional scaling was used to order the species by their functional traits. The demographic rates were fit a posteriori to the ordination, with significant rates (p < 0.05) plotted as vectors. The relationships between environmental conditions and the community-weighted means (CWMs) of trait values were verified using redundancy analysis. CWM wood density was positively correlated with soil pH. CWM leaf area and CWM maximum tree height were both negatively correlated with altitude and positively correlated with soil magnesium (Mg) content. The taller species with lower wood density, which occupied the forest canopy, had a greater diameter increment and lower recruitment than did the shortest species with higher wood density. The shorter species with higher wood density, which occupied the understory, had greater recruitment and a greater increase in abundance than did the taller/lower-wood-density species. Our study (i) revealed changes in the forest related to the light environment, with an increase in the relative participation of shade-tolerant species with higher wood densities, and (ii) detected small-scale spatial variation in community traits as a response to variations in soil chemical properties and topography.

The research aimed to evaluate the effect of Beauveria bassiana and Metarhizium anisopliae on Africanized Apis mellifera L. 1758 (Hymenoptera: Apidae). The application methods of entomopathogens suspensions were: 1) sprayed on eucalyptus leaves; 2) sprayed directly onto workers honey bees; and 3) incorporated in a candy paste. Sterilized distilled water that was offered to bees was used as a control. Each treatment consisted of five replicates of 20 bees. The longevity of the workers was checked from one to 144 hours. To study the effect of entomopathogenic fungi on morphometric parameters of produced queens, two cycles were performed: A) B. bassiana and control and B) M. anisopliae and control. For this, the transfer of worker larvae to acrylic domes containing royal jelly incorporated with the treatments was carried out. After nine days, the queen cells were placed in glass jars individually and stored in an acclimatized chamber until emergence, at which point the measurements of live weight were taken and morphometric analyses were performed. Beauveria bassiana caused a reduction in the survival of workers in the direct spray bioassay and when the entomopathogen was incorporated into the candy paste, while M. anisopliae caused a reduction in the survival in the three bioassays. The entomopathogenic fungi did not interfere negatively with the parameters evaluated for queens produced. [ABSTRACT FROM AUTHOR]

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For the analyze the floristic groups of a Mixed Ombrophylous Forest, in the county of Nova Prata were used 71 plots with dimensions of 10 x 100 m distributed systematically in the study area. Were sampled and identified the individuals with circumference at breast height (CBH) equal to or above 30.0 cm. The Cluster analysis was conducted using the Ward connection method and Euclidean distance as a measure of dissimilarity. The presence of four distinct floristic groups was verified; Matayba elaeagnoides, Lithraea brasiliensis, Campomanesia xanthocarpa and Myrciaria floribunda species presented the highest values of abundance. Group 3 (forest in adavanced stage) presented higher diversity of species and floristic similarity with the forest in general. The results evidence the need to consider the floristic groups in the case of developing a forest management plan. [ABSTRACT FROM AUTHOR]

For the maintenance and conservation of riparian areas it is necessary to know the layer's of the forest, like the natural regeneration of. According to that, the porpoise of this paper is to characterize the natural regeneration of a riparian forest in the city of Jaguari, central region in Rio Grande do Sul, by describing the diversity, structural parameters of natural regeneration, dispersion syndromes and ecological groups. For the sampling were plotted systematically 15 samples with size 5 × 10 m. Inside the plots were identified and measured the trees with height (h) equal or greater than 1.5 m, and diameter at breast height (DBH) less than 10 cm. Were sampled 546 individuals from 16 families and 26 species. The family Myrtaceae presented the highest number of species (6 species) and the greatest percentage of trees (54.8%). The Shannon's index was equal to 2.21 nats.ind-1 and Pielou's index was equal to 0.68, indicating low diversity and an uniform distribution among the species. Eugenia uniflora L. was the most characteristic species of natural regeneration. We observed that there is a deficit of small-sized individuals (0,3 ≤ DAP < 1,3 cm; 1,5 ≤ h < 2,5 m). The zoochoryc syndrome was most expressive in natural regeneration, being the main form to spread diaspores on place. Most species were classified as initial secondary (50%) or pioneer (26.9%), indicating that the riparian vegetation is altered, this indicate that riparian vegetation is in phase of recuperation of antropic activities. [ABSTRACT FROM AUTHOR]