Post-Harvest Silviculture Influences Survival, Growth and Projected Biological Rotation of Dinizia Excelsa in Amazonian Logging Gaps

Selective logging in Amazonian forests often fails to ensure demographic recovery of low-density, high-value timber species within conventional cutting cycles. We evaluated the long-term (17-yr) effects of three post-harvest silvicultural treatments (1 – control; 2 – tending of natural regeneration; and 3 – enrichment planting) on survival, growth, structural development, and projected biological rotation of Dinizia excelsa in reduced-impact logging (RIL) gaps in eastern Amazonia. Mortality dynamics were modeled using generalized linear mixed-effects models, and growth responses were assessed through linear mixed-effects models accounting for gap-level clustering. Enrichment planting exhibited higher early mortality, but significantly greater diameter (0.817 cm yr−1) and volume increments compared to tending and control treatments. After 17 yr, diameter-class distributions revealed accelerated structural advancement under planting. A bootstrap-based projection framework incorporating size-dependent growth deceleration indicates potential reductions in time to reach the 50 cm commercial threshold under assisted densification relative to unmanaged gaps. While projections should be interpreted as scenario-based estimates rather than deterministic forecasts, results demonstrate that targeted gap-based silviculture can enhance productivity and improve demographic trajectories of low-density hardwoods within operational RIL systems. Assisted densification emerges as a strategic complement to conventional management for improving long-term sustainability of Amazonian timber production.