Affonso Celso Gonçalves Junior

This study estimates the annual generation of ash from biomass combustion in boilers at slaughterhouses in Paraná, based on animals slaughtered under federal inspection in 2024 and thermoenergetic parameters reported in the literature. The methodology converted slaughter volumes into species-specific thermal demand, which was then translated into biomass consumption used as fuel, considering ranges of lower heating value; finally, ash production was estimated using ash contents between 0.5 and 0.8%. The resulting estimates were 91–154 t yr⁻¹ for cattle, 540–912 t yr⁻¹ for swine, and 167–282 t yr⁻¹ for poultry, totaling 798–1,348 t yr⁻¹ of ash generated. Low seasonality was observed, with monthly variations below 18%, and the swine sector accounted for approximately 60% of total ash generation, indicating a continuous supply of residue from cattle, swine, and poultry slaughtering. The results provide a quantitative baseline for ash management planning in Paraná’s meat-processing sector, indicating potential for valorization through agronomic, cementitious, and sustainable biosorbent pathways, subject to physicochemical characterization and regulatory compliance. Further performance testing, environmental risk assessment, and techno-economic analysis are recommended to confirm applicability at scale.

The increasing concern about Cd contamination, a toxic metal that accumulates in the environment and enters the food chain, poses risks to human health and the environment. This research focuses on remediation methods such as phytoremediation using Crambe abyssinica and bioremediation with plant growth-promoting bacteria (PGPB), highlighting their potential to reduce Cd bioavailability. The experiments were carried out in a protected cultivation system in Paraná, Brazil, using a randomized block design. Seeds were inoculated with A. brasilense and P. fluorescens under varying Cd doses. Evaluated variables included plant growth, anatomical characteristics, and concentrations of macronutrients and Cd in plant tissue and soil. Results showed that bacterial inoculation significantly increased plant growth even under Cd contamination. Inoculated plants exhibited greater root and shoot length, as well as improved vascular structure in xylem and phloem. Nutrient analysis revealed better macronutrient uptake and greater Cd accumulation, especially in aerial plant parts. The results confirm that phytoremediation and bioremediation are effective strategies for mitigating Cd contamination in agricultural soils. Inoculation with PGPB not only improved plant health and growth but also enhanced Cd accumulation capacity, supporting their use in sustainable remediation strategies. The techniques presented offer sustainable approaches for managing environmental risks associated with toxic metals.

Assessing the risks of pesticide use in the environment, especially in groundwater, requires predicting their movement. Pesticide leaching models represent an accessible and economical method to predict groundwater and surface water pollution and should be calibrated based on experimental data to better understand the dynamics of pesticides in soil and ensure their efficiency. This long-term study explored the ability of the MACRO model to describe water movement and atrazine distribution along the profile of a Rhodic Ferralsol cultivated with corn in western Paraná, Brazil, using data from a drainage lysimeter under high intensity simulated rainfall (150 mm h-1). The soil parameters analyzed in the laboratory were used as pedotransfer functions. The initial simulations showed significant differences, due to the particularities of the model and the complexity of the soil and its pore space, so the tests adjusted the retention curve and the sorption parameters. After final adjustments to the model, the simulated atrazine mass results were evaluated. Calibration of pesticide concentrations required small changes in sorption and degradation rates, and the results were compared to quantities measured at a specific depth. The simulation of atrazine transport was considered acceptable, estimating 0.71, 4.63, and 3.05% of the total mass of atrazine in percolate, runoff and retained in the profile, respectively.

The microbial communities present in cavities, especially in iron lithology environments, remain largely unknown. The isolation and characterization of cave microbiota are essential for identifying new species and obtaining substances of biotechnological relevance, such as antimicrobial compounds and microorganisms capable of bioremediating heavy metals. The objective of this study was to evaluate the antimicrobial activity and metal tolerance of bacteria isolated from the soil of caves GEM-1423 and GEM-1462 located in the Campos Ferruginosos National Park, in Serra de Carajás, Pará, Brazil. The bacteria were isolated from soil in different zones of the caves (photic, penumbra and aphotic) and subjected to antimicrobial susceptibility tests using the disk-diffusion technique and assessment of tolerance to metals by determining the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (CBM). Regarding the resistance profile, the bacteria showed high resistance to the antimicrobials Trimethoprim, Ampicillin and Amoxicillin. All bacteria showed tolerance to the metals Fe, Mn, Pb, Mg and K. These data are fundamental to understanding the potential of these microbial communities in iron lithology environments, thus contributing to the advancement of knowledge around ​​cave microbiology, with implications significant for environmental biotechnology and conservation of underground ecosystems.