Pioneer tree responses to variation of soil attributes in a tropical semi-deciduous forest in Brazil

ABSTRACT

The occurrence of pioneer tree species inside tropical forests is usually associated with canopy openness due to disturbances. The distribution of these species under different environmental conditions, aside from light presence, can be influenced by other variables such as soil attributes, water availability, and non-arborous species presence. This work evaluates pioneer tree distribution in the Pindorama Biological Reserve, Brazil, with respect to altitude, soil attributes, and non-arborous species in 65,400-m² plots in two toposequences of semi-deciduous forest. We evaluated the physical and chemical soil attributes altitude, basal area, height, and number of individuals of tree species with diameter at breast height (DBH) ≥5 cm in a randomly chosen quadrant in each plot. Pioneer trees were characterized by the following higher occurrence species: Acacia polyphylla, Aloysia virgata, Casearia sylvestris, and Croton floribundus. Cluster analysis suggested five similar groups among sampling plots. For each group, the mean of altitude, physical and chemical soil attributes, and degree of non-arborous species infestation was calculated. Principal components analysis correlated variables with pioneer tree data. C. floribundus occurred at low altitudes at lower or higher fertility, C. sylvestris occurred in lower fertility plots, and A. polyphylla and A. virgata occurred in higher altitude plots.

KEYWORDS:

• Acacia polyphylla
• Aloysia virgata
• Casearia sylvestris
• Croton floribundus
• soil attributes tropical tree species
• tropical forest species

Acknowledgments

The authors would like to thank CAPES-CNPQ for supporting this study and for the doctoral scholarship. We also acknowledge the APTA for enabling work at the Pindorama Biological Reserve and UNESP-FCAV, Campus Jaboticabal-SP, Brazil and to Dr. Ricardo Marques Coelho for soil classification.

Funding

This work was supported through a research grant from the CNPq to the first author.

Additional information

Funding

This work was supported through a research grant from the CNPq to the first author.