Atributos funcionais da flora arbórea e arbustiva de campina e campinarana na Amazônia Central

Abstract

The phyto-physiognomies which are found on white sand (podzol) in the Central Amazon occurr in a fragmented way along the biome and are named “campinas” and “campinaranas”. They comprehend a unique set of physiognomic variations on edaphic components with low contents of mineral nutrients and, in some cases, subjected to water saturation. To understand the physiognomic variation of the “campinas” to the “campinaranas” is necessary to evaluate the functional attributes that respond to environmental changes, being they either morphological (eg., specific wood density, specific leaf area, DBH – diameter at breast height, height) as physiological (eg., concentration of micronutrients in the leaves). This present study had the following objectives: (i) understand the role the edaphic factors in the distribution of values of the individual functional attributes of the tree flora and shrubs at different physiognomies of “campinas” and campinaranas in Central Amazonia, (ii) determine whether there is a functional pattern between the “campinas” and “campinaranas” from two different localities, regardless of their geographical location and floral composition. Two sites were selected for this study, the Jaú National Park (PARNA Jaú) and the Sustainable Development Reserve Uatumã (RDS Uatumã), both located in the Central Amazon. Principal Component Analysis (PCA) was applied and through it was possible to observe the formation of two distinct groups, separating the distribution of functional attributes of the individuals from the “campinas” from those of the “campinarana” in both study areas, for most of the evaluated attributes. However, the physiognomic variation was not explained by edaphic components of vegetation, since they did not vary between the different phyto-physiognomies. Therefore, the factor water saturation of the sandy soils, which is different in the “campinas” when compared to “campinaranas”, corresponds to the possible explanation of the vegetational structural variation between these two phyto-physiognomies.