Data/hora: 06/06/2024 12:04:32

Biblioteca(s): 	Embrapa Instrumentação; Embrapa Pecuária Sudeste.	
Data corrente: 	10/03/2022	
Data da última atualização: 	08/11/2023	
Autoria: 	TADINI, A. M.; GORANOV, A. I.; MARTIN NETO, L.; BERNARDI, A. C. de C.; OLIVEIRA, P. P. A.; PEZZOPANE, J. R. M.; HATCHER, P. G.	
Afiliação: 	ANA MARIA TADINI, USP; ALEKSANDAR I. GORANOV, Old Dominion University; LADISLAU MARTIN NETO, CNPDIA; ALBERTO CARLOS DE CAMPOS BERNARDI, CPPSE; PATRICIA PERONDI ANCHAO OLIVEIRA, CPPSE; JOSE RICARDO MACEDO PEZZOPANE, CPPSE; PATRICK G. HATCHER, Old Dominion University.	
Título: 	Structural characterization using 2D NMR spectroscopy andTMAH-GC × GC-MS: application to humic acids from soils of anintegrated agricultural system and an Atlantic native forest.	
Ano de publicação: 	2022	
Fonte/Imprenta: 	Science of The Total Environment, v.815, apr. 2022, 152605.	
Páginas: 	14 p.	
DOI: 	https://doi.org/10.1016/j.scitotenv.2021.152605	
Idioma: 	Inglês	
Conteúdo: 	Understanding the chemical make-up of soils and their structure is critical for constraining the role of soil organic mat-ter (SOM) into the global biogeochemical cycles, as well as to understand the capability of SOM to sequester carbonand mitigate greenhouse gas emissions. Here, we use two-dimensional1H-13C heteronuclear single quantum coher-encenuclear magnetic resonance (2D1H-13C HSQC NMR) spectroscopy to structurally characterize the most refractorycomponent of SOM, the humic acid (HA). The observations from 2D1H-13C HSQC NMR were coupled with lignin phe-nol and fatty acid measurements using tetramethylammonium hydroxide (TMAH) thermochemolysis?two-dimensional gas chromatography?mass spectrometry (TMAH-GC × GC-MS). We studied humic acids extractedfrom an integrated Crop?Livestock?Forest System (CLFS) agricultural area and an undisturbed Atlantic Native Forest(NF) area. We evaluated soils from two different depths: the topsoil (0?20 cm) and subsoil (60?100 cm) layers, andreveal the presence of oxidized ligninaceous phenols as we had previously hypothesized. Collectively, our results indi-cate that there are significant oxidative processes with increasing soil depth which are more pronounced in the CLFSrelative to the NF area. Degradation of stearic acid with increasing depth in the CLFS soils indicated that the CLFS ismore microbiologically active than NF. Therefore, CLFS is less biochemically stable than we originally perceived.The enhanced bio-reactivity of CLFS is likely driving the enhanced carbon sequestration in the CLFS soils. This is perhaps dueto the diversityof biomass remnants available at the CLFS soil rhizosphere which allowsfor more differenttypes of biomass to be sequestered as oxidized ligninaceous phenols. Our results employing structural characterizationwith 2D1H-13C HSQC NMR and TMAH-GC × GC-MS provide a new layer of knowledge about the practice of inte-grated agricultural systems and allow us to understand the structure and fate of sequestered carbon in soils from dif-ferent soil environments.	
Palavras-Chave: 	2D1H 13CHSQCNM; ILPF; Lignin phenols; TMAH thermochemolysis.	
Thesaurus Nal: 	Humic acids; Integrated agricultural systems; Soil organic matter.	
Categoria do assunto: 	P Recursos Naturais, Ciências Ambientais e da Terra	
Registro original: 	Embrapa Pecuária Sudeste (CPPSE)	
Exemplares: 	CPPSE - (25573-1) - UPC - AP - DD - PROCI-2022.00004 - TAD - 2022.00004 - DIS
CNPDIA - (17932-1) - UPA - AP - DD - PROCI.22/03 -  - 2022/03 - DIS