Biology subjects

Antonini, Y.

Publications and source records attributed to Antonini, Y..

4 recordsLinked to original sources

bioRxiv2023

Intra and interspecific diversity in a tropical plant clade alter herbivory and ecosystem resilience

Declines in biodiversity generated by anthropogenic stressors at both species and population levels can alter emergent processes instrumental to ecosystem function and resilience. As such, understanding the role of biodiversity in ecosystem function and its response to climate perturbation is increasingly important, especially in tropical systems where responses to changes in biodiversity are less predictable and more challenging to assess experimentally. Using large scale transplant experiments conducted at five neotropical sites, we documented the impacts of changes in intraspecific and interspecific plant richness in the genus Piper on insect herbivory, insect richness, and ecosystem resilience to perturbations in water availability. We found that reductions of both intraspecific and interspecific Piper diversity had measurable and site specific effects on herbivory, herbivorous insect richness, and plant mortality. The responses of these ecosystem-relevant processes to reduced intraspecific Piper richness were often similar in magnitude to the effects of reduced interspecific richness. Increased water availability reduced herbivory by 4.2% overall, and the response of herbivorous insect richness and herbivory to water availability were altered by both intra and interspecific richness in a site dependent manner. Our results underscore the role of intraspecific and interspecific richness as foundations of ecosystem function and the importance of community and location specific contingencies in controlling function in complex tropical systems.

ecology↗

bioRxiv2021

Riparian forest restoration as sources of biodiversity and ecosystem functions in anthropogenic landscapes

AO_SCPLOWBSTRACTC_SCPLOWO_LIRestoration of tropical riparian forests is challenging, since these ecosystems are the most diverse, dynamic, and complex physical and biological terrestrial habitats. This study tested whether biodiversity can predict ecosystem functions in a human-impacted tropical riparian forest. C_LIO_LIWe explored the effects of several biodiversity components (taxonomic or functional groups) on different ecosystem functions associated with restored riparian forests C_LIO_LIOverall, 49% of the biodiversity components showed positive effects on ecosystem functions, each component to a different degree. In general, our results showed that both taxonomic and functional biodiversity had strong effects on ecosystem functions indicating that floral and faunal biodiversity enhanced the multifunctionality of these restored riparian tropical forests. C_LIO_LIThese findings indicate that in restored riparian forests, recovery of biodiversity is followed by improvement in important ecosystem functions that are the basis for successful restoration. Future research and policy for restoration programs must focus on restoring elementary faunal and floral components of biodiversity in order to promote ecosystem multifunctionality. C_LI

ecology↗

bioRxiv2021

Is bigger always better? Neither body size nor aggressive behavior are good predictors to measure the degree of specialization of hummingbird interaction networks in rocky outcrops

Interspecific competition can strongly influence community structure and shape niche breadth and overlap. One of the main factors that determine the hummingbird community structure is competition for food. Hummingbirds functional attributes, such as beak length and body mass, influence nectar acquisition in the flowers, shaping foraging niches according to hummingbird dominance and foraging strategy. This study evaluates how the hummingbirds functional and behavioral attributes are related to plants assemblage in rocky outcrops habitats. We tested the following hypothesis: H1) Functional traits (beak length and body mass) are related to the richness and frequency of pollen grain morphotypes carried by hummingbirds; H2) Dominant and territorial hummingbirds carry a lower richness and frequency of pollen types when compared to subordinate hummingbirds, and H3) Hummingbird species carry different types of pollen grains. We conducted the study between September 2018 and March 2019 in a Campo Rupestre (rocky outcrops) in Southeastern Brazil. Hummingbirds were captured with a trap built based on trapdoors. We recorded their beak size and body masses, marked with commercial bird rings and ink on parts of the body, and then released. Behavioral responses to artificial feeders were collected regarding each visits time and duration and the outcome of aggressive interactions. The pollen adhered to the body parts was collected and identified in the laboratory. Our results showed that neither body size nor aggressive behaviors influenced pollen richness and frequency in rocky outcrops. Beak length was the most important hummingbirds attribute that influenced pollen richness, but not pollen frequency. Short-billed hummingbirds carried the greatest richness of pollen grains. Pollen grain richness and frequency were not related to hummingbird body mass or aggressive behavior. The hummingbird-pollen grain interaction network has shown to be generalized in the pollen grain transport. We conclude that hummingbirds beak length is the central morphological variable to measure pollen grain transport. It has direct implications for the pollination of different plant species.

ecology↗

bioRxiv2020

The mistletoe Struthanthus flexicaulis reduces dominance and increases diversity of plants in campo rupestre

The interaction between hemiparasites and their host plants is an important structuring mechanism for plant communities. The mistletoe Struthanthus flexicaulis (Loranthaceae) is widely distributed in the campo rupestre ecosystem and likely has an important role in structuring the communities of which its hosts are part. The main goals of this study were to investigate the effects of parasitism by S. flexicaulis on host plants in a degraded area of campo rupestre and to determine how parasitism affects characteristics of the structure of this plant community over time. We found that parasitized plants had smaller crowns and branch growth, and suffered lower mortality compared to non-parasitized plants. Parasitism by S. flexicaulis decreased dominance and increased the diversity and evenness of plants in the community over time. Parasitism leads to competition with the host for water and nutrients, which may decrease the performance of the host and, consequently, leading to host death. The high mortality of the most abundant plant species led to a restructured woody plant community. These results reinforce the importance of parasitic plants as key species for maintaining species diversity in plant communities.

ecology↗