Structure, survival, and species diversity in a tropical dry forest submitted to coppicing

Abstract

The Caatinga is a tropical dry forest. Rational exploitation of Caatinga wood resources consists of sustainable forest management under coppice systems. Therefore, the recovery of the timber stock for the next cycle will depend on the regrowth and survival capacity of the exploited species, as well as on the future structure of the forest. The objective of this work was to characterize the survival, structure, and diversity of Caatinga submitted to coppicing under sustainable forest management comparing pre- and post-harvest conditions. Permanent plots were installed in a Caatinga in the municipality of Floresta-PE, Brazil, in 2013, and measured 2 years after clearcutting. Height and circumference at the base (CAB) of the stumps and shoots were obtained for two situations: pre-cut (grouping by live and dead stumps) and (ii) post-cut (shoots on only live stumps). In addition, all individual shrub-tree species (CAB ≥ 4 cm) not included in the post-cut situation were identified, measured (CAB and height total) and tagged as persisting (6 cm ≤ CAB) or growing (6 < CAB ≤ 4 cm) in 2015. The survival and mortality of the stumps were quantified, as well as changes in the horizontal structure and floristic diversity. There was a decrease in the number of species 2 years after cutting, mainly due to the loss of Croton rhamnifolius H. B. K. and Sapium glandulatum (Vell.) Pax and predominance of Cenostigma bracteosum (Tul.) E. Gagnon & G. P. Lewis, Aspidosperma pyrifolium Mart., and Cnidoscolus quercifolius Pohl., resulting in a greater number of individuals of a few species. The outstanding regrowth capacity of these three species indicates that the forest remnant under study may eventually consist of populations with a predominance of species capable of coppicing.