Influência do ácido úmico (Humix) no desenvolvimento inicial de mudas de espécies nativas do Cerrado

Abstract

The Cerrado biome, renowned for its vast biodiversity, faces significant degradation challenges stemming from agricultural expansion and low natural soil fertility. This study investigated the influence of humic acid on the growth and development of seedlings from native Cerrado species (Caroba Roxa, Aroeira, Tamboril, and Gonçalo Alves), aiming to foster more efficient and sustainable restoration practices. The experiment was conducted under controlled conditions, utilizing substrates with varying concentrations of humic acid, and evaluated parameters including root growth, shoot biomass, leaf area, and seedling survival rate. Results indicated that humic acid application significantly enhanced root and shoot biomass, alongside improving seedling height and diameter, particularly at moderate concentrations (1.20; 1.80 ml). However, humic acid concentrations of 2.40 and 3.00 ml led to increased seedling mortality, indicating a need for dosage adjustments. The lack of adequate phosphorus quantities in the employed bio-input was also identified as a limiting factor for root development. Therefore, employing humic acid represents a promising strategy for the biofortification of native seedlings, holding potential for soil quality improvement and the restoration of degraded areas. Further investigations under field conditions and exploring combinations with other bio-inputs are recommended to optimize outcomes.