Estudo comparativo de métodos para a determinação da concentração de carbono em solos com altos teores de Fe (Latossolos)

Segnini, A.; Santos, Lucas da Silva; Silva, Wilson Tadeu Lopes da; Martin‐Neto, Ladislau; Borato, C.E.; Melo, Wanderley José de; Bolonhezi, Denizart

doi:10.1590/s0100-40422008000100020

Cited by 30 publications

(24 citation statements)

References 6 publications

(9 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Due to its high specific surface area and the diversity of functional groups, the OM can interact with the organic molecules of different shapes. The possible mechanisms involved in the interaction among herbicides of low water solubility, such as oxadiazon (Garbi et al, 2006), with 0.57 mg L -1 (Footprint, 2013), and the OM are hydrogen bonding, Van der Waals forces, hydrophobic interactions and charge transfer, and they can operate concurrently in the sorption of the same molecule (Sheng et al, 2001). The molecular ** p < 0.01 by the F test.…”

Section: Resultsmentioning

confidence: 99%

“…However, the direct effect on the OC was negatively unrepresentative, highlighting the high magnitude of the indirect effect of the OM, because the OC is a major component of the OM of the soil and its stock is influenced by the management system adopted (Steiner et al, 2011), where it is assumed that the OM of the soil contains 58% of OC (Segnini et al, 2008).…”

Section: Sorption Of Oxadiazon In Soils Cultivated In the Brazilian Cmentioning

confidence: 99%

See 1 more Smart Citation

Sorption of oxadiazon in soils cultivated in the brazilian cerrado

et al. 2014

View full text Add to dashboard Cite

-The objective of this study was to evaluate oxadiazon sorption in different soils of the Brazilian Cerrado, highlighting the correlations of lethal doses of this herbicide capable of inhibiting 50% of the dry matter accumulation of the bio-indicator (LD50) among the chemical characteristics of the soil and its direct and indirect effects. The experiment was carried out in a greenhouse in a randomized block design and four repetitions. Each experimental unit consisted of a pot with increasing rates of oxadiazon and oat (Avena sativa), as the bio-indicator species. For sorption evaluation, washed sand and 22 soils (substrates) from Cerrado Brazilian's Alliaceae cultivated areas were used. LD50 and sorption ratio (SR) = [(LD50soil -LD50sand)/ LD50sand] to the substrates were determined. Pearson correlation analysis was performed between the chemical characteristics of the substrates and the LD50 of oxadiazon. A path analysis was quantified, to deploy only the significant correlations estimated in direct and indirect effects of the characters on LD50, which is a basic variable. A more pronounced LD50 (528.09 g ha -1 ) for the Cerrado soil sample resulted in higher SR (> 53.00), while in the washed sand substrate, LD50 corresponded only to 9.74 g ha -1 of the oxadiazon (available in soil). It was concluded that oxadiazon sorption is influenced by the chemical characteristics of the soils, highlighting the correlation with pH (CaCl 2 ), magnesium content, aluminum, organic matter, organic carbon, and aluminum saturation.Keywords: bioassay, neutral herbicide, organic matter. RESUMO -Objetivou-se neste estudo avaliar a sorção do oxadiazon em diferentes solos do Cerrado Brasileiro, destacando as correlações da dose letal do herbicida capaz de inibir 50% do acúmulo da massa seca do bioindicador (DL50) entre as características químicas do solo e seus efeitos diretos e indiretos. O experimento foi realizado em casa de vegetação, com delineamento em blocos casualizados com quatro repetições. Cada unidade experimental foi constituída de um vaso com doses crescentes do oxadiazon; utilizou-se a aveia (Avena

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Sorption Of Oxadiazon In Soils Cultivated In the Brazilian Cmentioning

confidence: 99%

Sorption of oxadiazon in soils cultivated in the brazilian cerrado

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Hence, underestimation of C content in soil samples from areas subjected to fire (i.e., those producing sugarcane or soybean and maize in Brazil), is expected if WB methods are used. Trends for overestimating soil C content with the WB method were observed by Segnini [117], which could be a result of the high iron content of Oxisols. Using the WB method, they found that C content was underestimated by 18% when compared to the EA method when all samples were compared.…”

Section: Laboratory Analysis-walkley-black Titration Methods (Wb) Versmentioning

confidence: 91%

“…To illustrate the implications of different analytical procedures, data from four studies carried out in agricultural soils of Brazil comparing WB and EA methods for total C quantification were compiled in Figure 3. Soil analyses from the upper 5 cm of a clayey Oxisol of Central Brazil (Cerrado biome) cropped to different maize rotations were provided by Coser [49], while those from Segnini [117] also corresponded to Oxisols but from the Northern São Paulo state. In a third study [118], soil total C data came from different soils planted to eucalyptus from eastern Minas Gerais, including Oxisols.…”

Section: Laboratory Analysis-walkley-black Titration Methods (Wb) Versmentioning

confidence: 99%

Review of Soil Organic Carbon Measurement Protocols: A US and Brazil Comparison and Recommendation

et al. 2017

View full text Add to dashboard Cite

Soil organic carbon (SOC) change influences the life-cycle assessment (LCA) calculations for globally traded bio-based products. Broad agreement on the importance of SOC measurement stands in contrast with inconsistent measurement methods. This paper focuses on published SOC research on lands managed for maize (Zea mays L.) in the U.S. and sugarcane (Saccharum officinarum L.) in Brazil. A literature review found that reported SOC measurement protocols reflect different sampling strategies, measurement techniques, and laboratory analysis methods. Variability in sampling techniques (pits versus core samples), depths, increments for analysis, and analytical procedures (wet oxidation versus dry combustion) can influence reported SOC values. To improve consistency and comparability in future SOC studies, the authors recommend that: (a) the methods applied for each step in SOC studies be documented; (b) a defined protocol for soil pits or coring be applied; (c) samples be analyzed at 10 cm intervals for the full rooting depth and at 20 cm intervals below rooting until reaching 100 cm; (d) stratified sampling schemes be applied where possible to reflect variability across study sites; (e) standard laboratory techniques be used to differentiate among labile and stable SOC fractions; and (f) more long-term, diachronic approaches be used to assess SOC change. We conclude with suggestions for future research to further improve the comparability of SOC measurements across sites and nations.

show abstract

“…Na determinação do CT foi utilizado um Analisador de Carbono (Organic Carbon Analyser, TOC-V) -1500 da SHIMADZU, equipado com módulo de amostrador de sólidos SSM -1.500 ºC, devidamente calibrado (Segnini et al, 2008); o NT foi extraído por digestão sulfúrica, seguido de destilação Kjeldahl. A densidade do solo foi obtida pelo método do anel volumétrico.…”

Section: Methodsunclassified

Variação nos atributos do solo em sistemas de manejo com adição de cama de frango

Valadão¹,

Maas²,

Weber

et al. 2011

Rev. Bras. Ciênc. Solo

View full text Add to dashboard Cite

RESUMOA cama de frango constitui-se em adubo orgânico com boas características agronômicas, podendo ser bom condicionador das propriedades físicas do solo. Assim, o objetivo deste trabalho foi verificar alterações nas propriedades do solo em sistemas de plantio direto com adição de cama de frango. O estudo foi feito em três camadas (0-10, 10-20 e 20-30 cm) e três repetições, em Latossolo VermelhoAmarelo distrófico submetido a plantio direto contínuo nos últimos anos, com rotação principalmente de soja, milho, algodão e milheto. Os tratamentos foram: sistema com adubação mineral (S2), com adição de cama de frango crua (S3), com adição de cama de frango compostada (S4) e uma área não manejada de Cerrado nativo (S1). Os sistemas de manejo induziram em ordem crescente -S4, S2, S3 -à degradação dos atributos do solo em relação à vegetação nativa (S1), e isso foi quantificado pelos menores valores de carbono total, diâmetro e estabilidade de agregados, macroporosidade e condutividade hidráulica saturada e pelos maiores valores de densidade e resistência do solo à penetração e microporosidade. A cama de frango crua revelou-se mais vantajosa na disponibilidade de nitrogênio total e menos eficiente em garantir a qualidade física do solo. A cama de frango compostada proporcionou atributos mais semelhantes às condições naturais.Termos de indexação: resíduo orgânico de avicultura, composto de aviário, propriedades físicas do solo.

show abstract

Estudo comparativo de métodos para a determinação da concentração de carbono em solos com altos teores de Fe (Latossolos)

Cited by 30 publications

References 6 publications

Sorption of oxadiazon in soils cultivated in the brazilian cerrado

Sorption of oxadiazon in soils cultivated in the brazilian cerrado

Review of Soil Organic Carbon Measurement Protocols: A US and Brazil Comparison and Recommendation

Variação nos atributos do solo em sistemas de manejo com adição de cama de frango

Contact Info

Product

Resources

About