This paper describes the phenology of leaf, flower, and fruit phenology in the Atlantic rain forests of southeastern Brazil. For 17 months, we observed the phenological patterns of trees from two Atlantic forest types at four sites: premontane forest (Sites I and IV; the “typical” Atlantic rain forest) and coastal plain forest (Sites II and III). All sites experience a nonseasonal, tropical wet climate, characterized by an annual rainfall usually > 2000 mm and lacking a dry season. We tested for the occurrence (or absence) of seasonal phenological patterns within each site and compared the patterns detected among the four different forest sites using circular statistics. The expected weakly seasonal phenological patterns were not observed for these forests. Flowering and leaf flush patterns of Atlantic rain forest trees were significantly seasonal, concentrated at the beginning of the wettest season, and were significantly correlated with day length and temperature. These results stress the influence that seasonal variation in day length has on ever‐wet forest tree phenology. Fruiting phenologies were aseasonal in all four forests. Flowering patterns did not differ significantly among three of the four forest sites analyzed, suggesting the occurrence of a general flowering pattern for Atlantic rain forest trees.

Phenology of coastal-plain forest tree species from Southeastern Brazil). The present study aims to characterize the reproductive and leafing phenology of tree species of a coastal-plain forest from Southeastern Brazil and to relate the observed patterns with the local biotic and abiotic factors. The study was carried out in the Parque Estadual da Serra do Mar, Núcleo Picinguaba, Ubatuba, São Paulo State (23°22'30"S and 44°46'-44°51'45"W). The climate is tropical-wet, with a high rainfall, well distributed throughout the year. Monthly observations were carried out from July 1993 to June 1994 on 290 individuals of 46 tree species. The leaf fall was considered non-seasonal (Rayleigh test not significant), while leaf flushing > 25%, flowering and fruiting were defined as weakly seasonal (Rayleigh test significant, but low r values). Flowering and leaf flushing were more intense during the wetter months, from November to February. Fruit production was constant along the year. Ninety percent of the species were defined as evergreen and 87% of the species present animal-dispersed fruits. The phenological patterns observed for the coastal-plain forest at Picinguaba were weakly seasonal, contrasting with the very seasonal patterns found in the semideciduous forests from Southeastern Brazil. RESUMO-(Fenologia de espécies arbóreas em floresta de planície litorânea do sudeste do Brasil). O presente estudo visou determinar os padrões fenológicos reprodutivos e vegetativos para espécies arbóreas da floresta superúmida de planície litorânea e relacionar os padrões observados com os fatores próximos (abióticos) e os evolutivos (bióticos). O estudo foi realizado no Parque Estadual da Serra do Mar, Núcleo Picinguaba, Ubatuba, São Paulo (23°22'30"S e 44°46'-44°51'45"W). O clima da região é tropical chuvoso, com precipitação alta e bem distribuída ao longo do ano. Observações fenológicas foram realizadas mensalmente, de julho de 1993 a junho de 1994 em 290 indivíduos pertencentes a 46 espécies arbóreas. A fenofase queda de folhas não foi sazonal (teste Rayleigh não significativo), enquanto as demais fenofases foram pouco sazonais (teste Rayleigh significativo, mas com valores baixos de r). A floração e o brotamento foram mais intensos nos meses mais úmidos, de novembro a fevereiro, enquanto a frutificação ocorreu ao longo do ano. Cerca de 90% das espécies não são decíduas, com predomínio da dispersão por animais (87%). A floresta de planície mostrou padrões fenológicos pouco sazonais, bastante distintos dos observados para as florestas semidecíduas do interior do estado de São Paulo.

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Habitat loss is the main driver of the current high rate of species extinction, particularly in tropical forests. Understanding the factors associated with biodiversity loss, such as the extinction of species interactions and ecological functions, is an urgent priority. Here, our aim was to evaluate how landscape‐scale forest cover influences fruit biomass comparing different tree functional groups. We sampled 20 forest fragments located within landscapes with forest cover ranging from 2 to 93 percent in the Atlantic forest of southern Bahia, Brazil. In each fragment, we established five plots of 25 × 4 m and carried out phenological observations on fleshy fruit throughout 1 year on all trees ≥5 cm dbh. We estimated fruit availability by direct counting of all fruits and derived fruit biomass from this count. We used spatial mixed linear models to evaluate the effects of forest cover on species richness, abundance, and fruit biomass. Our results indicated that forest cover was the main explanatory variable and negatively influenced the total richness and abundance of zoochoric and shade‐tolerant but not shade‐intolerant species. A linear model best explained variations in richness and abundance of total and shade‐tolerant species. We also found that forest cover was positively correlated with the fruit biomass produced by all species and by the shade‐tolerant assemblages, with linear models best explaining both relationships. The loss of shade‐tolerant species and the lower fruit production in fragments with lower landscape‐scale forest cover may have implications for the maintenance of frugivore, seed dispersal service, and plant recruitment.

As tropical rainforests are cleared, forest remnants are increasingly isolated within agricultural landscapes. Understanding how forest loss impacts on species diversity can, therefore, contribute to identifying the minimum amount of habitat required for biodiversity maintenance in human-modified landscapes. Here, we evaluate how the amount of forest cover, at the landscape scale, affects patterns of species richness, abundance, key functional traits and common taxonomic families of adult trees in twenty Brazilian Atlantic rainforest landscapes. We found that as forest cover decreases, both tree community richness and abundance decline, without exhibiting a threshold. At the family-level, species richness and abundance of the Myrtaceae and Sapotaceae were also negatively impacted by the percent forest remaining at the landscape scale. For functional traits, we found a reduction in shade-tolerant, animal-dispersed and small-seeded species following a decrease in the amount of forest retained in landscapes. These results suggest that the amount of forest in a landscape is driving non-random losses in phylogenetic and functional tree diversity in Brazil’s remaining Atlantic rainforests. Our study highlights potential restraints on the conservation value of Atlantic rainforest remnants in deforested landscapes in the future.

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