Assessment of demographic sustainability of Comanthera elegans under traditional management in the Brazilian savanna

Nontimber forest product (NTFP) agroextractivism plays a critical role in the livelihoods of billions and offers the potential to balance sustainable development with biodiversity conservation. However, its sustainability depends on analyzing species' vital rates and local management practices because extraction can contribute to their conservation or deplete NTFP populations and ecosystems. We integrated demographic and ethnobiological approaches to evaluate how traditional management affects the population dynamics of Comanthera elegans L. R. Parra & Giul, a Brazilian endemic herb considered at risk of extinction due to harvesting pressures. Over 3 years, we conducted a demographic experiment with 28,441 individuals in the Sempre-Vivas National Park to examine the effect of the traditional harvest and management practices of the Sempre-Vivas Flower Pickers on the species' vital rates. We used six treatments, including variations in traditional harvest times (early or late), traditional use of fire, and control conditions. Fecundity rates, population growth, seedling and adult mortality, and flowering were monitored across 120 plots. Early harvests decreased fecundity and population growth due to reduced seed viability, whereas late harvests combined with fire increased flowering and population growth rates. Fire improved soil conditions by enhancing pH and potassium levels. The improved soil conditions lowered seedling mortality and increased population resilience. These results suggest that traditional fire and harvest management practices contribute to the long-term sustainability of C. elegans populations. We propose that national conservation policies decriminalize these practices because they support sustainable resource use thus enhancing biodiversity conservation and local livelihoods. Our results underscore the need to integrate traditional ecological knowledge into the management and conservation of NTFPs in the Brazilian savanna.