Seasonal, multi-scale spatial and slope-oriented effects in cambial dynamics: an evaluation of sampling methods in Cedrela odorata (Meliaceae) in an Atlantic Forest area.

Studies of cambial dynamics have been employed to investigate the growth behavior of trees. In these investigations, however, spatial variation in cambial rhythm within the stem is usually not taken into account. This study aims to evaluate the contribution of multiple sampling scales on the cambial dynamics of Cedrela odorata L. (Meliaceae) in different seasons. The effects of slope orientation were also tested. Samples were processed and analyzed with standard plant histology techniques. Data from multiple sampling scales were analyzed with nested ANOVA for each season, and the total variance was partitioned according to the fraction related to each scale. The main sources of variability were associated with the scale of tree and scales smaller than 1 cm. Radial growth was not significantly related to acclivity orientation. Thus, to obtain samples that represent total variability in cambial dynamics, it is preferable to increase the number of sampled trees; to take multiple samples from a few millimetres apart from each other, or to assess multiple histological sections. Samples on scales greater than a few centimetres apart should not be given priority. [ABSTRACT FROM AUTHOR]