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Forest islands are unique habitats standing out across mountains dominated by rupestrian grassland in southeastern Brazil. In this work we evaluated the relationship between the plant species functional traits (number of ecoregions in which a species occurs, potential height, mean height, mean basal area, mean leaf area) and ecological variables (leaf damage from chewing herbivores, the number of individuals) with environmental parameters (physical and chemical properties of the soil, canopy cover) of the tree communities in an archipelago of montane forest islands immersed in rupestrian grasslands. We found a strong connection between the traits of tree species and environmental parameters; habitats associated with high soil fertility and canopy cover (leaf area index) harbored species with high structural values (i.e., height and basal area), broad distribution among Brazilian ecoregions, high rates of leaf damage from chewing insects and fewer individuals. Habitats with low soil fertility and canopy cover values harbored species with low structural values, restricted geographic distribution and low rates of leaf damage by chewing insects. Although physical parameters play an important role in the establishment of forest islands, our results point to chemical indicators of soil fertility as a relevant environmental promoter, influencing the composition and structure of island tree communities. The impact of local habitat parameters on the tree species functional traits showed that habitat heterogeneity is essential in structuring tree communities in this natural archipelago of forest islands. We advocate that understanding the connection between habitat parameters and species functional traits can help to predict the ecological consequences of anthropogenic or natural impacts to those forests, supporting the development of effective conservation strategies.

Species that evolved in high-altitude grasslands, where soils are dystrophic and metal rich, developed adaptations for these extreme conditions, such as metal accumulation and sclerophyllous leaves, and these adaptations may secondarily affect insect herbivory activity. The present study investigates the hypothesis that costs related to accumulation of certain metals may be evolutionarily compensated for by decreasing leaf herbivory in some plant species from rupestrian fields. Studies were conducted in different locations at the Ferriferous Quadrangle, a metal-rich region in south-east Brazil, with four species adapted to high-altitude grasslands: Eremanthus erythropappus, Eremanthus incanus, Lychnophora ericoides and Byrsonima variabilis. Sample design varied according to population sizes and spatial distribution of individuals. We found that concentrations of manganese (Mn) and iron (Fe) significantly reduced the herbivory in the leaves of E. erythroppapus and E. incanus, whereas aluminum (Al) reduced herbivory in L. ericoides, and Mn affected negatively the herbivory in B. variabilis. These results support the hypothesis that metal-accumulating plants, as a response to the harsh environment in which they evolved, are protected against foliar damage caused by insect herbivores in rupestrian fields.

Herbivory is ubiquitous. Despite being a potential driver of plant distribution and performance, herbivory remains largely undocumented. Some early attempts have been made to review, globally, how much leaf area is removed through insect feeding. Kozlov et al., in one of the most comprehensive reviews regarding global patterns of herbivory, have compiled published studies regarding foliar removal and sampled data on global herbivory levels using a standardized protocol. However, in the review by Kozlov et al., only 15 sampling sites, comprising 33 plant species, were evaluated in tropical areas around the globe. In Brazil, which ranks first in terms of plant biodiversity, with a total of 46,097 species, almost half (43%) being endemic, a single data point was sampled, covering only two plant species. In an attempt to increase knowledge regarding herbivory in tropical plant species and to provide the raw data needed to test general hypotheses related to plant-herbivore interactions across large spatial scales, we proposed a joint, collaborative network to evaluate tropical herbivory. This network allowed us to update and expand the data on insect herbivory in tropical and temperate plant species. Our data set, collected with a standardized protocol, covers 45 sampling sites from nine countries and includes leaf herbivory measurements of 57,239 leaves from 209 species of vascular plants belonging to 65 families from tropical and temperate regions. They expand previous data sets by including a total of 32 sampling sites from tropical areas around the globe, comprising 152 species, 146 of them being sampled in Brazil. For temperate areas, it includes 13 sampling sites, comprising 59 species. Thus, when compared to the most recent comprehensive review of insect herbivory (Kozlov et al.), our data set has increased the base of available data for the tropical plants more than 460% (from 33 to 152 species) and the Brazilian sampling was increased 7,300% (from 2 to 146 species). Data on precise levels of herbivory are presented for more than 57,000 leaves worldwide. There are no copyright restrictions. Please cite this paper when using the current data in publications; the authors request to be informed how the data is used in the publications.

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Currently, we are facing many ecosystem changes derived from years of anthropogenic disturbances. Habitat simplification stands out among human-derived impacts, due to its detrimental effects on vegetation structure and associated biota. Here, we assessed the effects of litter disturbance and forest simplification on a tropical ground-foraging ant community. To do that, we tested whether ant richness will be negatively affected by litter disturbance and habitat simplification. Additionally, we tested whether litter disturbance affects the time of resource discovery and dominance, and if so, whether its effects are intensified by forest simplification. This study occurred at Rio Doce State Park, a preserved area of Atlantic Forest in Southeastern Brazil. We experimentally simulated litter disturbance by removing the leaf litter and superficial soil layer in a mahogany monoculture forest and preserved Atlantic Forest. We sampled ants using paired-mixed baits of protein and carbohydrate in 12 points, half of them in each forest type. As expected, we found higher richness in the preserved and non-disturbed forest. Moreover, resource discovery was faster in disturbed monoculture, but bait dominance was higher in the undisturbed preserved forest. Litter heterogeneity seems to play an important role in determining ant dispersion and intra-specific communication, as we observed that litter disturbance impacts were strengthened by forest simplification. Our results highlight the efficiency of ground-foraging ants as bioindicators of disturbance and habitat quality. Moreover, our study indicates how distinct types of disturbances can act synergistically, changing the assembly of associated biota.

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Plants adapted to different habitats exhibit differences in functional traits and these characteristics are in uenced by soil properties. We tested the hypothesis that soil resource availability in uences the functional traits of plants, affecting therefore herbivory levels. We examined three Byrsonima plant species with different life forms that occurred across a distinct edaphic habitat along the Doce River Basin, South-eastern Brazil. We characterize habitats according to soil nutrient concentration and measured functional characteristics of crown architecture, leaf nutrients, sclerophylly, leaf area and leaf density. In addition, we evaluated how these variables in uenced herbivory levels of congeneric plants.Our data have shown that species along a gradient of soil nutrients have functional characteristics in uenced by habitat, which in turn affected herbivory levels. By comparing species from different life forms but within the same genus along a stress-gradient of continuous habitats, we described a corresponding gradient of plant functional traits and tissue consumption by herbivorous insects.