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-(Post-dispersal seed predation of Anadenanthera falcata (Benth.) Speg. (Leguminosae-Mimosoideae) in a gallery forest in Barra do Garças, MT, Brazil). Seed predation is one of the bottlenecks for the regeneration of tropical trees. The influence of post-dispersal seed predation of A. falcata on seedling recruitment was studied in a gallery forest in "Parque Estadual da Serra Azul" (PESA) in Barra do Garças, MT. Field experiments were designed to assess the differences in post-dispersal seed predation by vertebrates and invertebrates with regards to temporal and spatial variation, leaf litter and distance from parent tree. Ants Solenopsis (Diplorhoptrum) sp. were the main seed predator of A. falcata. Seed mortality by insects varied through the fruiting season; it was more intense at the beginning and at the end of the fruiting season. The survivorship of seed did not vary among different microhabitats and was independent of litter cover and proximity to an adult fruiting tree. The results of this study indicated that predation by ants can limit the recruitment of A. falcata. However, rainfall reduces predation rate by promoting seed germination and favouring seedling recruitment of A. falcata.

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Aims Litterfall at a global scale is affected by climate, edaphic features, and vegetation structure, with litter production increasing from grasslands to forests following the rise in standing biomass. However, at landscape scales, the same relationship between litter production and vegetation structure has rarely been studied and comparisons of litterfall patterns between adjacent, structurally distinct communities are lacking. Here we use a standardized methodology to describe the structural differences among four savanna physiognomies and analyze their relationship with changes in litterfall across the Cerrado. Methods We evaluated the woody vegetation structure and composition in 48 sites, equally distributed across four physiognomies, and monitored the monthly litter production from April 2014 to March 2015. Important Findings Results showed that the density, basal area, cylindrical volume, and aboveground biomass of woody vegetation differ among physiognomies, increasing consistently from cerrado ralo, cerrado típico, cerrado denso, and cerradão. Indeed, we found a strong and positive relationship between aboveground biomass and annual litter production, with litter yield increasing from 0.9 to 8.4 Mg ha-1 across different physiognomies, following the increment in vegetation structure. Monthly production was seasonal and similar among vegetation types, increasing during the dry season. Leaves comprised the dominant fraction (approx. 85%) and litterfall seasonality primarily resulted from the concentration of leaf shedding during dry months. However, the temporal pattern of litterfall throughout the year showed a gradual reduction in the seasonality from open to closed vegetation types, likely following the decrease of deciduous species abundance in the plant community. Our results showed that changes in vegetation structure may affect spatial and temporal litterfall patterns in different physiognomies, which co-occur across the Cerrado landscape, with potential implications for the overall functioning of this ecosystem. Moreover, these findings highlight the use of standardized methods as essential to correctly compare litterfall patterns among different environments.