The present study evaluated the effects of biochar derived from sugarcane straw on the physicochemical and biological properties of soil and the initial development of sugarcane. Microcosm and pot experiments were conducted over 60 days to monitor variables such as pH, water retention capacity, microbial activity, initial growth, and the metabolomic profile of the plant leaves. The results indicated that biochar increased the soil water retention capacity without significantly affecting the pH. The biochar significantly promoted root length and mass and favored the growth of the soil microbiota, as reflected by an increase in the amount of microbial biomass carbon. Metabolomic analysis of sugarcane leaves revealed that soil conditioning with biochar at application rates of 3 and 5% w/w led to increased concentrations of the amino acids isoleucine and valine, accompanied by a reduction in galactose, maltose, and glucose levels. Furthermore, biochar treatment resulted in a decrease in aconitic acid and an increase in acetic and succinic acid concentrations. These findings suggest that biochar may be a promising strategy for enhancing the productivity and sustainability of sugarcane cultivation.

Portland cement production is one of the main global sources of CO₂ emissions, driving the search for sustainable solutions to reduce its environmental footprint. This study evaluated the use of biochar derived from sugarcane bagasse as a partial cement replacement in cementitious composites, aiming to investigate its effects on mechanical and microstructural properties. Composites were prepared with 0, 2, and 5 (% w w⁻¹) biochar at two water-to-cement (w/c) ratios: 0.28 and 0.35. It was hypothesized that the porous structure and carbon-rich composition of biochar could enhance the microstructure of the cementitious matrix and contribute to strength development. Characterization of the biochar indicated compliance with the European Biochar Certificate (EBC) standard, high thermal stability, and notable water retention capacity. Mechanical testing revealed that incorporating 5% w w⁻¹ biochar increased compressive strength by up to 48% in the 0.35 w/c formulation compared to the control. Microstructural analyses (SEM/EDS) showed good interaction between the biochar and the cementitious matrix, with the formation of hydration products at the interfaces. The results confirm the potential of sugarcane bagasse biochar as a supplementary cementitious material, promoting more sustainable composites with improved mechanical performance and reduced environmental impact.

O objetivo deste trabalho foi produzir e caracterizar o biocarvão a partir da palha de cana-de-açúcar, bem como investigar possíveis efeitos fitotóxicos às germinações de algodão, milho e soja. Para tanto, o biocarvão foi produzido em forno de duplo tambor e caracterizado por diferentes técnicas. Os ensaios de germinação foram conduzidos in vitro, com doses de biocarvão variando entre 0 e 100 t/ha. O biocarvão foi obtido com rendimento de 40%, pH igual a 9,10, condutividade elétrica de 2,22 dS/m e área superficial específica de 20,3 m²/g. A análise elementar mostrou razões atômicas H/C e O/C de 0,41 e 0,21, respectivamente. A FTIR mostrou a presença de grupos C=C, enquanto a MEV/EDS mostrou estrutura porosa tipo favo de mel e nutrientes, como o Mg, K e Ca. O ensaio de germinação classificou o biocarvão como fitoestimulante para o milho e mostrou ausência de fitotoxicidade para soja. Por outro lado, para o algodão, as doses mais elevadas (50 e 100 t/ha) causaram fitotoxicidade. Os resultados deste trabalho vêm ao encontro das demandas globais por técnicas verdes. O biocarvão feito da palha de cana-de-açúcar é uma tecnologia promissora para melhorar a infertilidade de solos pobres e gerir o sequestro de carbono.

Eficácia do ácido indolbutírico de sementes de Phaseolus vulgaris L. e do fungo Trichoderma sp. No enraizamento e desenvolvimento de estacas de aceroleira / Efficacy of indolbutyric acid from seeds of Phaseolus vulgaris L. and fungus Trichoderma sp. In rooting and development of acerola cuttings