Bioactivity and Chemical Characteristics of Humic Acids From Tropical Soils Sequence

Canellas, Luciano P.; Zandonadi, Daniel Basílio; Busato, Jader Galba; Baldotto, Marihus Altoé; Simões, Marcelo Luiz; Martin‐Neto, Ladislau; Façanha, Arnoldo Rocha; Spaccini, Riccardo; Piccolo, Alessandro

doi:10.1097/ss.0b013e3181847ebf

Cited by 54 publications

(64 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The 13 C NMR spectra of HA indicated the increase of hydrophobicity (sum of aromatic and alkyl C) with increasing soil C stability (Piccolo, 2001;Ikeya et al, 2004;Spaccini et al, 2006;Xiaoli et al, 2007;Conte et al, 2007;Canellas et al, 2008). This hydrophobicity in HA as a result of increased stability had previously been shown in association with the quinone moieties Perez et al, 2004;Canellas et al, 2007Canellas et al, , 2008 of HA.…”

Section: Introductionmentioning

confidence: 93%

“…This hydrophobicity in HA as a result of increased stability had previously been shown in association with the quinone moieties Perez et al, 2004;Canellas et al, 2007Canellas et al, , 2008 of HA.…”

Section: Introductionmentioning

confidence: 98%

“…The samples were air-dried, ground, sieved (2 mm) and stored for characterization in the laboratory. Details of soil organic matter fractionation, HA isolation, purification and elementary composition, functional group contents, oxidation capacity, as well as ultraviolet-visible (E 4 /E 6 ), fluorescence (FI), nuclear magnetic resonance (NMR 13 C) and electron spin resonance (ESR) spectroscopy for the HA have previously been presented and discussed by Baldotto et al (2007Baldotto et al ( , 2008, Canellas et al (2008) and Dobbss et al (2008Dobbss et al ( , 2009). Some of the soils and HA properties were selected and are shown in the tables 2 and 3, respectively.…”

Section: Sampling and Characterization Of Soil And Humic Acidsmentioning

confidence: 99%

“…These sites were described and characterized (Table 1) by Baldotto et al (2007Baldotto et al ( , 2008, Canellas et al (2008) and Dobbss et al (2008Dobbss et al ( , 2009). The study also included an Entisol under continuous sugarcane cultivation over the course of 55 years (Canellas et al, 2003Busato et al, 2005a,b;Baldotto et al, 2008).…”

Section: Brazilian Soilsmentioning

confidence: 99%

“…The SFRC was quantified by electron spin resonance (ESR) spectroscopy and correlated with indexes estimated by ultraviolet-visible (E 4 /E 6 ), fluorescence intensity (FI), nuclear magnetic resonance (NMR 13 C) and infra-red spectroscopies Perez et al, 2004;Canellas et al, 2007Canellas et al, , 2008 of HA. Kononova (1961) introduced an index of humification degree based on Russian soils, the E 4 /E 6 ratio, i.e., the relation of absorbances at 465 and 665 nm, and attributed low E 4 /E 6 values to a high humification degree.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Redox index of soil carbon stability

Baldotto

Canela²,

Canellas

et al. 2010

Rev. Bras. Ciênc. Solo

View full text Add to dashboard Cite

SUMMARYAs an alternative to the relatively complex and expensive spectroscopic methods, the redox properties of humic acids, determined by potentiometric titrations, have been used to evaluate the stability of soil organic C. The objective of the present study was to establish a Redox Index of C Stability (RICS) and to correlate it with some properties of the humic acids extracted from different modal soils in Brazil (distinct weathering stages or management) to facilitate system comparison. The RICS was efficient for soil comparison and variations were comparable to those of the chemical and spectroscopic methods used for humic acid characterization. The values of soil pH, point of zero salt effect, sum of bases, exchangeable Ca content, weathering index, as well as the humic acid O/C ratio, quinone and semiquinone free radical contents, aromatic C and fluorescence intensity were closely related with the RICS. The RICS was higher in less weathered soils, with more active clays and higher fertility. The RICS values of soils under long-term sugarcane management were ranked in decreasing order: unburned, burned with vinasse, burned without vinasse.Index terms: soil chemistry, soil organic matter, humic substances, oxidation capacity.(1) Part of the doctoral and post doctoral works from the first author developed at the State University of the North Fluminense "Darcy Ribeiro" -UENF.

show abstract