Crescimento e características funcionais de espécies florestais em plantio para a recuperação de área perturbada

Abstract

The current scenario of deforestation in the Legal Amazon is represented by a total of about 42 million hectares of altered areas only between 1988 and 2016. The revegetation of these areas from reforestation programs presupposes adequate species selection. The success in the initial establishment (survival and growth) of the species in disturbed areas depend on the performance of the functional processes that affect the growth rates. The objective was to investigate how the functional traits explain the growth variation of forest species planted in disturbed area after abandoned area and vegetation remotion). The relative growth rates in height (TCR-a) and diameter (TCR-d) and functional traits were analyzed in eight native forest species (Bombacopsis macrocalyx, Cedrela odorata, Ceiba pentandra, Endlicheria anomala, Hymenaea courbaril, Ochroma pyramidale, Tachigali Vulgaris and Trattinnickia rhoifolia) 15 months after planting. T. vulgaris, T. rhoifolia and O.pyramidale had the highest relative growth rates in height and diameter, while B. macrocalyx had the lowest growth. TCR-a and TCR-d were on average 2.5 times higher for the faster growing species (T. vulgaris) relative to the slower growing species (B. macrocalyx). Morphological (leaf area and specific leaf mass) and physiological traits (water potential, leaf nutrient and chlorophyll content), which are usuallyassociated with the relative growth rates, were not strong predictors of the growth variation ofthe eight species studied here. The best predictors were: maximum photosynthesis (A max ), instantaneous carbon use efficiency (EUC) and photosynthetic macronutrient use efficiency, mainly phosphorus (EUP). The growth rates increased with increasing of A max , EUC and EUP. The mean variation in growth rates explained by the three individual functional traits (A max , EUC and EUP) was about 25%. The observed relationship between growth and functional traits can improve the selection of native forest species for the composition of planting models in reforestation programs in disturbed areas.