Microclima e características funcionais da vegetação regulam a dinâmica da serrapilheira ao longo de um gradiente altitudinal em floresta montana tropical

Abstract

Litter dynamics represent a fundamental process for nutrient cycling and the maintenance of productivity in tropical forests, especially in montane environments, where altitudinal gradients promote strong environmental variation over short distances. In this dissertation, we investigated how microclimatic variables and vegetation attributes influence patterns of litterfall and decomposition along an altitudinal gradient (1,700 to 2,500 m) in an Atlantic montane tropical forest in Brazil.The study was conducted in permanent plots distributed across five elevation levels, where litterfall and decomposition were monitored using litterbags. In addition, we continuously recorded microclimatic variables, including temperature, precipitation, and humidity. Structural and functional vegetation attributes associated with the tree community were also assessed. The results indicated that litterfall was positively associated with mean temperature, precipitation, and thermal variability, highlighting a strong microclimatic control over organic matter production. Furthermore, vegetation functional traits influenced decomposition, with traits associated with acquisitive strategies promoting greater mass loss. Overall, the findings demonstrate that small microclimatic variations along the altitudinal gradient can significantly alter organic matter fluxes and nutrient cycling, while the functional composition of vegetation modulates litter quality. These results underscore the importance of integrating microclimatic measurements and functional traits to better understand the functioning of montane tropical forests under climate change.