Montane forest tree species have lower hydraulic efficiency and vulnerability than lowland forest species in the Atlantic Forest

Abstract The adaptations of plants to different environments are closely related to their wood anatomical traits. This study investigated the wood anatomy of a montane forest community and compared it with anatomical data from three other areas in the Atlantic Forest biome (montane and lowland forest). Samples from 23 montane forest species were processed and analyzed according to standard wood anatomy techniques. Quantitative xylem traits were measured and conductivity parameters were calculated. Wood anatomical data for 76 species from other areas were obtained from previous studies and incorporated into the analyses. Shared wood features indicated ecological trends related to the forest formations. Species of the sampled montane forest were discriminated into groups based on their qualitative and quantitative features, especially those related to ray and xylem conduction traits. Hydraulic traits were also important for distinguishing forest communities along the altitudinal gradient. The montane forest communities had lower conductivity and higher hydraulic safety than the lowland forest community. Apart from these differences, all the studied communities are in the Atlantic Forest biome and present traits related to high hydraulic efficiency and vulnerability, as expected for this tropical region

Annual tree rings in Piptadenia gonoacantha (Mart.) J.F.Macbr. in a restoration experiment in the Atlantic Forest: potential for dendroecological research

ABSTRACT The tree Piptadenia gonoachantha is widely used in forestry and in forest restoration projects, which require methods for evaluating tree growth. Long-term studies are necessary to determine patterns and detect changes in species growth rhythms. Tree ring analysis provides a precise method for determining age and documenting long-term growth trends in tropical tree species. The present study evaluated the periodicity of tree ring formation and radial growth dynamics of P. gonoachantha from a population of known age in the Poço das Antas Biological Reserve. Two radii from six trees were sampled using non-destructive methods. Tree rings were counted and measured to estimate age and to calculate diametric increment. All samples had 16 tree rings, which matched the known plantation age and confirmed the annual formation of rings. The individuals sampled had a mean annual diametric increment of 9.5 mm / year. Results showed a trend towards decreasing growth rate with increasing age. Individuals of P. gonoachantha in Ombrophilous Dense Forest produce annual tree rings, which holds potential for future dendroecological studies