Secondary succession in the Caatinga is composed of species that persist throughout all chronosequence

  • JCR分区:

    影响因子:

  • Several models explain succession in secondary forests, but none are universally accepted. Classical models suggest species replacement, while newer ones propose that early species may persist throughout succession. To better understand how species composition and groups change over time in the Caatinga, we analyzed the structure and organization of plant communities in 13 fragments aged between 7 and 52+ years. We sampled the woody component within a 10 x 100 m plot, recording species richness, abundance, and floristic composition. Species richness increased throughout succession, but most species (66 %) found in the early stages (7-15 yr) persisted across the chronosequence, including in the old-growth forest. Communities' age did not affect soil properties, suggesting no abiotic improvement during succession. However, species composition varied with vegetation age (F = 54.7; df = 11; p-value = 0.003). Changes in the abundance of dominant species and the gradual accumulation of rare species have explained this variation. We concluded that the Caatinga follows an alternative succession model that integrates elements from different theoretical frameworks. Due to its open physiognomy and sparse canopy, shade tolerance is not key for succession. Instead, early species remain dominant across all stages, while rarer species accumulate over time.