Banca de DEFESA: NATÁLIA FERNANDES RODRIGUES

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : NATÁLIA FERNANDES RODRIGUES
DATE: 31/08/2026
TIME: 14:00
LOCAL: VIDEOCONFERÊNCIA
TITLE:

Development, Characterization, and Evaluation of a Biopolymer-Coated Organo-Mineral Soil Regenerator Based on Urea, Biochar, and Humic Substances

KEY WORDS:

controlled-release fertilizers; urea; biochar; humic acid; nitrogen efficiency.

PAGES: 80
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUMMARY:

The intensive use of conventional nitrogen fertilizers is associated with nitrogen losses in agricultural systems, reducing nutrient use efficiency and contributing to environmental impacts. In this context, this study aimed to develop and evaluate controlled-release nitrogen fertilizers using urea, biochar, and humic acid as matrix components and a biopolymer as a coating. The formulations were established through a mixture design, in which the proportions of the main components were varied while the remaining components were maintained at constant proportions. The resulting formulations were characterized according to their chemical, structural, and surface properties, including nutrient contents, organic carbon, C:N ratio, cation exchange capacity, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy. Nitrogen release in water was evaluated over time, and the data were fitted to different kinetic models to assess the influence of matrix composition and coating on nutrient release behavior. The formulations were also evaluated for nitrogen losses through volatilization and in a maize crop experiment. The results showed that changes in component proportions promoted differences in the chemical, morphological, and surface characteristics of the formulations, while the coating modified nitrogen release behavior. The developed formulations showed reduced nitrogen volatilization losses compared with urea. In the maize experiment, the fertilizers showed efficiency comparable to urea, demonstrating their potential as controlled-release nitrogen sources. Overall, the results indicate that the combination of the matrix components and biopolymer coating represents a promising strategy for developing fertilizers capable of modifying nitrogen availability and reducing nutrient losses in agricultural systems.

COMMITTEE MEMBERS:
Presidente - 1399485 - ANDRES CALDERIN GARCIA
Externa à Instituição - CAMILA PINHEIRO NOBRE - UEMA
Interno - 2626406 - LEANDRO AZEVEDO SANTOS
Interno - 387406 - RICARDO LUIZ LOURO BERBARA
Externo à Instituição - SAEL SÁNCHEZ ELÍAS - UFRRJ