Variação funcional de espécies arbóreas ao longo de um gradiente hidro-edáfico de campinarana na Reserva de Desenvolvimento Sustentável do Uatumã

Abstract

By understanding the variation in the functional characteristics of plant communities, we provide a better understanding of the factors that affect future changes in the composition of this planning. It is an important tool for studies in Campinarana ecosystems, characterized by a distinct terrain, which have adaptations and specific morphological and physiological characteristics, which allow them to develop in these locations, which have different phytophysiognomes and are under constant threat. In this dissertation, we investigated how the hydro-edaphic gradient acts on the composition of the functional characteristics of campinarana tree species from the Uatumã Sustainable Development Reserve (RDS) in the Central Amazon. We seek to answer the following questions: How does the hydro-edaphic gradient of Campinaranas influence the functional variation in the characteristics of tree communities? What strategies do tree communities adopt along the gradient? How are the characteristics of the leaves, trunk and bark coordinated with each other? For this, eleven plots measuring 50 x 50 meters were used, installed along a hydro-edaphic gradient in Campinarana. From the inventory, the five most abundant tree species with a diameter at breast height (DBH at 1.30 cm from the ground) ≥10 cm were selected in each plot, totaling 30 species. Leaf traits (specific leaf mass, leaf thickness, leaf area, leaf density), and wood traits (height, DBH, wood density, bark thickness, bark density) of the dominant tree species were measured and related to the availability of water and nutrients in the soil. We found that environments with greater soil charm drive functional convergence in leaf traits across communities. Fertility, on the other hand, drove functional divergence in leaf traits and cascades. We also found that water availability is the main predictor of the functional media of communities, directing the strategies of tree species, which are acquisitive in more charming environments, conservative in environments with deeper water tables. We also identified a coordination of leaf, stem and cascade traits varying along a single axis, corresponding to the spectrum of global leaf and wood economy integrated into the cascade. We report that, although Campinaranas are known to be oligotrophic ecosystems, we selected sets of traits mainly related to resource conservation, Campinarana environments with shallow water tables, we selected sets of traits more related to resource acquisition, such as taller trees, lower wood density, less dense and thick bark, greater leaf mass per unit area.