(Eff ect of linear edges in the phenology of animal dispersed tree species in a remnant of Atlantic Forest). Th e dispersal of seeds is one of the crucial phases of the life cycle of plants and plant phenology is among the factors that regulate the dispersal mode and activity of dispersers. In landscapes subject to fragmentation, the distribution of dispersal syndromes may be modifi ed due to changes in fl ora composition and structure caused by edge eff ects, which may also change plant phenodynamics. In this study, the dispersal syndromes (zoochory, anemochory and autocory) of 162 tree species were identifi ed and, for 57 of these species, this information was related to diff erent measures of fruiting phenology (activity index, percentage of Fournier intensity and intensity weighted by basal area) in environments of linear edges and forest interior. In all environments there was a predominance of animal dispersed species and, in general, the distribution of syndromes did not diff er among environments. Considering the three environments together, zoochorous and anemochorous species had continuous fruiting, while the autochorous fruiting pattern was intermittent. When the environments were analyzed separately, the fruiting phenodynamics of animal dispersed species (N = 44) diff ered among the three environments. Th e results indicate the existence of edge eff ects on fruiting phenology of species dispersed by animals, despite the absence of these eff ects in the distribution of dispersal syndromes. Th is suggests that the passage of electric transmission lines and gas pipelines in remnants of Atlantic Forest may aff ect the temporal dynamics of fruit availability for frugivores, with possible consequences for plant-seed disperser interactions, even when it does not lead to a decrease in the total supply of resources for these animals.

Plant reproductive success is supposedly influenced by phenology and individual size, which may be modified under edge effects. We tested if reproductive success, estimated by fruit set, in Senefeldera verticillata (Euphorbiaceae) is related to flowering synchrony and tree size, including plant height and circumference at breast height. The study was carried out in the interior and in edges of clearings for gas pipelines and electric lines of a lowland rainforest in south-eastern Brazil. Monthly observations were performed during one reproductive season, of 19 individuals that grew at edges of electric lines and gas pipelines and at forest interior. Reproductive success was significantly higher at forest interior than at gas pipeline area; there was no significant difference between gas pipeline and electric line areas or between forest interior and electric line area. In the forest edges, only plant height was positively related to plant reproductive success. This is probably related to crown exposure to sunlight, which enhances flower production. At forest interior, reproductive success was positively influenced by the synchrony of flowering activity among neighbouring individuals. In contrast, flowering synchrony based on phenophase intensity negatively impacted reproductive success. Senefeldera verticillata shows temporal dioecy and is mainly pollinated by small social bees, and the high degree of flowering synchrony at low intensity may increase the number of mating partners and therefore enhance its reproductive success. Inside the forest fragments, individuals with thicker trunks showed lower reproductive success, which may be related to a loss of reproductive capacity of older individuals. Our results evidenced the complexity of responses experienced by tropical plants subjected to forest fragmentation because of linear clearings.

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In the Brazilian Amazon, forest fragments increase annually leading many species to local extinction. Euxylophora paraensis Huber is an endemic species whose natural habitat is restricted to the north of Brazil. The natural regeneration was evaluated using 10 circular plots of land each with a radius of 20 meters. The density of regenerating individuals at the edge and the interior of the fragment and the behavior in relation to the parent tree. The Periodic Annual Increment of the diameter and the height were calculated individually for each plant that remained alive during all four measurements and GLM (General Linear Model) was applied to verify if there were differences between environments and the size of the individuals.  The results show that the density of natural regeneration increases as the distance from the parent tree increases and has a significant negative correlation with canopy area, the smaller the canopy area the higher the density of individuals. Larger diametric growth was observed in saplings and small trees at the edge and larger increments of height in small trees were observed both at the edge and interior of the fragments. Therefore, natural regeneration is influenced by the process of forest fragmentation where the germination of seeds and establishment of saplings is favorable, however, there were no adult trees at the edge.