标题：Spatial relationships between Ananas ananassoides (Bromeliaceae) and Tachigali vulgaris (Fabaceae) influencing the structure of the Amazon/Cerrado transition in Brazil
摘要：In the present study, we tested the hypothesis that: a) bromeliad Ananas ananassoides individuals and Tachigali vulgaris tree individual have an aggregate distribution pattern, and b) are spatially dissociated. To this effect, we quantified all A. ananassoides and T. vulgaris individuals (DBH of at least 30 cm) in large plot (1 ha) composed by 100 subplots measuring 10×10 m in a savanna woodland in the Bacaba Municipal Park, Nova Xavantina, Mato Grosso. The spatial pattern of A. ananassoides and T. vulgaris, and their spatial relationships, were measured using the aggregation and the association index, respectively. Both species had an aggregate distribution pattern and were spatially dissociated, which corroborates the hypotheses of this study. In this case, the preferred occupation in gaps by both species and the growth of the bromeliad in clumps may be conditioning the populations’ spatial dependence. On the other hand, the bromeliad’s clump formation and the tree species shading may be mutually exclusive factors, which intensify their competition for space and light and reveal spatial incompatibility by these populations. Further studies should be conducted to better understand the interactions between the herbaceous and tree layer, incorporating the temporal dynamics of natural regeneration and habitat conditions.
