Biotic drivers of seedling establishment in Neotropical savannas: selective granivory and seedling herbivory by leaf-cutter ants as an ecological filter.

摘要: Summary Herbivory has been shown to have prominent top-down effects on vegetation in Paleotropical savannas, where consumers of early stages life history act as demographic bottlenecks. Such impact largely ignored Neotropical however, despite insect consumption being linked reduced recruitment woody species. We hypothesize that Atta leaf-cutter ants – the prevalent herbivores Neotropics alter establishment plant seedlings Brazilian Cerrado by reducing seed availability and seedling survival. We also will be species-specific. To test these hypotheses, we experimentally (i) compared removal areas with without foraging (ii) survivorship exposed or protected from foraging. Both experiments were performed same common species which allowed us evaluate potential net at population community levels. Overall rates sites greater than those absent (59.2% 39.2% seeds removed, respectively). There differences for 10 12 tested species, per 1.1- 3.8-fold On transplanted plants, 45% attacked, resulting a survival 7.6% lower seedlings. Seedling was 11.8–31.5% five largest between treatments during dry season. Taken together, results support hypothesis can lead bottlenecks savanna varying among life-history species. Synthesis. Granivory Cerrado. Our show may limit differential species-specific effects. therefore acting an ecological filter, coupled selectivity reproductive stages, ultimately influence relative abundance different hence structure composition vegetation.