Spectroscopic characteristics of humic acids extracted from soils under different integrated agricultural production systems in tropical regions

Autor(es)

Tadini, Amanda M. ^[1] ; Bernardi, Alberto C. C. ^[2] ; Milori, Debora M. B. P. ^[1] ; Oliveira, Patricia P. A. ^[2] ; Pezzopane, Jose R. M. ^[2] ; Martin-Neto, Ladislau ^[1]

Afiliação do(s) autor(es)

^[1] Embrapa Instrumentacao, Rua 15 Novembro 1452, BR-13560970 Sao Carlos, SP - Brazil

^[2] Embrapa Pecuaria Sudeste, Rd Washington Luiz, Km 234 Fazenda Canchim, BR-13560970 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: GEODERMA REGIONAL; v. 28, MAR 2022.
• Citações Web of Science: 0

Resumo

Soil Organic Matter (SOM) plays an important in many ecosystems on the planet. Therefore, we employed elemental analysis (CHN), fluorescence spectroscopy (EEM-CP/PARAFAC), and electron paramagnetic resonance (EPR) to characterize the humic acids (HA) extracted from soils under integrated agricultural production systems (e.g. agroforestry systems (AFS)). These systems (S) included Crop (C), Livestock (L), Forest (F), and different combinations of them (CLFS, LFS, and CLS), which were compared with pastures (intensive (INT) and extensive (EXT)) and native forest (NF). For this purpose, we collected samples of a dystrophic Red-Yellow Latosol from experimental field areas which it is located at the Embrapa Pecu ` aria Sudeste in Sao Carlos, Sao Paulo state, Brazil. Results showed that the HA humification index increased with soil depth, which is identified by complex structures more affluent in semiquinone-type free radical (SFR) and higher fluorescence intensity, especially in the AFS. Therefore, the HA from the CLFS systems had a higher aromaticity profile than HA from pastures and native forest areas, suggesting a longer lifetime to Carbon compounds. These significant findings are important for developing climate change mitigation strategies. (AU)

• Processo FAPESP: 17/22950-1 - Dinâmica, reatividade e aspectos estruturais da matéria orgânica de solos sob sistemas de integração lavoura-pecuária-floresta
• Beneficiário: Amanda Maria Tadini
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 17/20084-5 - Práticas estratégicas para mitigação das emissões de gases de efeito estufa em sistemas de pastagem do Sudeste brasileiro
• Beneficiário: Paulo Henrique Mazza Rodrigues
• Modalidade de apoio: Auxílio à Pesquisa - Programa de Pesquisa sobre Mudanças Climáticas Globais - Temático