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Item type:Publication, Mountain Ecosystems as Natural Laboratories for Climate Change Experiments(Frontiers Media S.A., 2020-03-31)Experimental studies are needed to empirically examine the effects of climate change on terrestrial organisms and to serve as the basis for predictions and management practices. As such, designing and implementing experimental systems that can simulate complex changes in the natural environment is currently a major area of interest of climate change science. Most climate change experiments (e.g., infrared heaters, open-top chambers) are typically performed within small, controlled environments and often manipulate just temperature and/or CO2 concentration. Other factors are more difficult to control (e.g., wind speed, soil moisture) or are frequently ignored (e.g., biotic interactions), leading to uncertainties in the results and limiting our ability to make realistic predictions about species’ responses to future environmental changes. We examined the natural variation of abiotic and biotic factors along mountain elevational gradients in order to highlight the potential for using these systems as natural laboratories for climate change research and experiments. The high variability of different abiotic and biotic factors along elevational gradients provides a good opportunity to carry out field transplant/translocation experiments aimed at answering some critical questions, including: How will new biotic assemblages affect key interactions and processes? What are the factors that influence species assemblages under novel climates? How do local abiotic factors influence the establishment of species migrating into novel and climatically suitable habitats? Based on empirical evidence, we strongly encourage researchers to take advantage of the natural environmental gradients found in mountains to study the potential direct and indirect impacts of climate change on species, communities and biodiversity as a whole. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Severe fires alter the outcome of the mutualism between ants and a neotropical savanna tree(Oxford University Press, 2020-01-01)Abstract Physical disturbances, such as fire, may affect the relationship between ants and plants. We evaluated the extent to which severe fires alter the protective effect of ants against the herbivores of an extrafloral-nectary bearing tree. We performed an ant removal experiment and sampled the ant fauna from the same trees over 4 years: the pre-fire year, the fire-year, and again 1 and 2 years later. Ants reduced insect herbivory in the pre-fire year and in the fire-year but failed to provide any plant protection in the two years after fire. The magnitude of the ant effect on herbivory did not differ between the pre-fire year and the fire-year. Fire reduced the abundance of ants with strictly arboreal-nesting habits. However, in the fire year (but not in the subsequent ones), this decline was compensated by an increase in the abundance of arboreal generalists and ground-nesting ants foraging in trees. Our results indicate that severe fires can affect the strength and direction of the ant effects on herbivory by altering the structure of the arboreal ant community and the abundance of insect herbivores. Fire disturbance is thus an important factor of conditionality of ant-plant mutualisms in fire-prone habitats, like the Cerrado savannas. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Multi‐population seedling and soil transplants show possible responses of a common tropical montane tree species (Weinmannia bangii) to climate change(Wiley, 2020-05-30)Abstract A possible response of many plant species to global warming is migration to higher elevations. However, these migrations may not be required if species can tolerate higher temperatures, or may be prevented if there are other factors such as changes in soil conditions that make upslope areas unsuitable. We used a set of 3‐year field transplant experiments in the remote Peruvian Andes to simulate two possible responses of an abundant tropical montane cloudforest tree species (Weinmania bangii) to global warming: (a) ‘upward migration’, in which case seedlings of W. bangii's were grown at their current elevation/temperature but in soils transplanted from higher elevations and (b) ‘migration failure’, in which case seedlings were transplanted downslope along with their home soils into areas that are 1°C or 2°C warmer. We conducted separate experiments with populations from the upper/leading edge, middle and lower/trailing edges of W. bangii's elevational/thermal range to assess the influence of local adaptation on responses to changes in temperature or soil. We found that seedling survival and growth were not affected by changes in soil conditions, regardless of the origin population. However, seedling survival decreased with temperature. A simulated warming of 1°C caused a significant reduction in the survival of seedlings transplanted from the mid‐range population, and 2°C warming caused a severe decrease in the survival of seedlings transplanted from both the mid‐range and bottom‐edge populations. Synthesis. Our findings reveal that rising temperatures are a serious threat to plants, especially in populations growing in the hotter portion of their species’ range. At least in the case of W. bangii, novel soil conditions will not limit the establishment or growth of seedlings at higher elevations. As such, decreases in the survivorship at lower elevations may be offset through upward migrations as temperatures continue to increase. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Revisiting florivory: an integrative review and global patterns of a neglected interaction(Wiley, 2021-08-07)Florivory is an ancient interaction which has rarely been quantified due to a lack of standardized protocols, thus impairing biogeographical and phylogenetic comparisons. We created a global, continuously updated, open-access database comprising 180 species and 64 families to compare floral damage between tropical and temperate plants, to examine the effects of plant traits on floral damage, and to explore the eco-evolutionary dynamics of flower-florivore interactions. Flower damage is widespread across angiosperms, but was two-fold higher in tropical vs temperate species, suggesting stronger fitness impacts in the tropics. Flowers were mostly damaged by chewers, but neither flower color nor symmetry explained differences in florivory. Herbivory and florivory levels were positively correlated within species, even though the richness of the florivore community does not affect florivory levels. We show that florivory impacts plant fitness via multiple pathways and that ignoring this interaction makes it more difficult to obtain a broad understanding of the ecology and evolution of angiosperms. Finally, we propose a standardized protocol for florivory measurements, and identify key research avenues that will help fill persistent knowledge gaps. Florivory is expected to be a central research topic in an epoch characterized by widespread decreases in insect populations that comprise both pollinators and florivores. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, The effects of high-severity fires on the arboreal ant community of a Neotropical savanna(Springer Science and Business Media Deutschland GmbH, 2021-08-01)Fire-suppression is of concern in fire-prone ecosystems because it can result in the loss of endemic species. Suppressing fires also causes a build-up of flammable biomass, increasing the risk of severe fires. Using a Before-After, Control-Impacted design, we assessed the consequences of high-severity fires on Neotropical savanna arboreal ant communities. Over a 9-year period, we sampled the ant fauna of the same trees before and after two severe fires that hit a savanna reserve in Brazil and the trees from an unburned savanna site that served as a temporal control. The ant community associated with the unburned trees was relatively stable, with no significant temporal variation in species richness and only a few species changing in abundance over time. In contrast, we found a strong decline in species richness and marked changes in species composition in the burned trees, with some species becoming more prevalent and many becoming rare or locally extinct. The dissimilarity in species richness and composition was significantly smaller between the two pre-fire surveys than between the pre- and post-fire surveys. Fire-induced changes were much more marked among species with strictly arboreal nesting habits, and therefore more susceptible to the direct effects of fire. The decline of some of the ecologically dominant arboreal ant species may be particularly important, as it opens substantial ecological space for cascading community-wide changes. In particular, severe fires appear to disrupt the typical vertical stratification between the arboreal and ground-dwelling faunas, which might lead to homogenization of the overall ant community. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, How much leaf area do insects eat? A data set of insect herbivory sampled globally with a standardized protocol(Ecological Society of America, 2021-04-01)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.