Influência do clima na herbivoria e produção de biomassa foliar em uma floresta da Amazônia Central

Abstract

Herbivory is a fundamental ecological process that acts in the transfer of energy between trophic levels and influences vegetation dynamics and biogeochemical cycles in tropical ecosystems. In Amazonian forests, it can affect primary productivity and nutrient cycling, especially through the modulation of litter production and quality. In this context, this dissertation investigates the dynamics of leaf production and herbivory in a terra firme forest in Central Amazonia, within the scope of the AmazonFACE experiment, between 2019 and 2022, evaluating the influence of climatic variables such as precipitation, temperature, and relative humidity. The results indicate that leaf dynamics are not determined solely by water availability, but by the interaction between plant physiological processes, herbivore activity, and microclimatic conditions. Seasonality was observed in leaf biomass production, with peaks associated with the dry season, while herbivory showed a distinct pattern, increasing in wetter months, evidencing a partial decoupling between leaf production and consumption. The analysis also revealed a time lag effect between herbivory and litter deposition, indicating its role as an integrator of canopy processes over time. Statistical models demonstrated significant effects of climatic variables, especially when considering time lags, highlighting the importance of non-immediate ecological responses. Precipitation stood out as an important modulator of herbivorous activity and leaf dynamics. Finally, the results highlight the functional complexity of Amazonian forests, where interactions between biotic and abiotic factors influence productivity, nutrient cycling, and carbon balance, contributing to the understanding of the resilience of these ecosystems in the face of climate change. KEYWORDS: Climate Seasonality; Leaf Phenology; Amazon Rainforest