Papers by deborah pinheiro dick
Diferentes sistemas agricolas afetam tanto a entrada como a exportacao de carbono (C) em funcao d... more Diferentes sistemas agricolas afetam tanto a entrada como a exportacao de carbono (C) em funcao da producao diferenciada de residuos, a qual e dependente do numero de cultivos anuais, das especies vegetais, da adubacao, do preparo e manejo do solo, entre outros. O objetivo deste trabalho foi avaliar o efeito de sistemas de preparo conservacionistas em solo de textura media nos teores de C e nitrogenio (N) do solo. O experimento foi instalado em um Argissolo Amarelo distrofico, Mâncio Lima, Acre, em 2006. O delineamento experimental consistiu em parcelas subdivididas em blocos (40 m x 50 m) ao acaso, com tres repeticoes, localizando-se o preparo convencional (PC) e o plantio direto (PD) nas parcelas principais (20 m x 50 m), e nas subparcelas (10 m x 20 m) foram estabelecidos os tratamentos T (testemunha), M (mucunapreta) e MPC (mucuna-preta+ fosforo+ calcario dolomitico). A cobertura utilizada desde o inicio do experimento e a mucuna-preta (Mucuna aterrima). Os teores de C e de N e a relacao C/N nao diferiram entre os tratamentos e entre os sistemas de manejo, em nivel de 5%. Em oposicao ao usualmente observado em solos subtropicais, o manejo conservacionista e a correcao da acidez do solo nao afetaram o teor de C apos 10 anos.
Social Science Research Network, 2021
Neste projeto foi estudada a matéria orgânica do solo in situ e suas frações humificadas por anál... more Neste projeto foi estudada a matéria orgânica do solo in situ e suas frações humificadas por análises de DRIFT e FTIR. Foram empregados dois tipos de solos que apresentavam teor de carbono total semelhante (20 mg/g solo): Latossolo Roxo (60% argila) e Brunizem (20% argila). A separação das substâncias húmicas foi realizada pela sua solubilidade em meio alcalino e em meio ácido na amostra de solo natural e na amostra de solo tratado com HF. Foi adaptada uma técnica de concentração da matéria orgânica com solução de HF 10 %, que solubiliza os componentes inorgânicos levando a um enriquecimento relativo da matéria orgânica da amostra. A análise da matéria orgânica do solo in situ por DRIFT forneceu maiores informações que a análise por FTIR. No solo Brunizem foi possível observar as bandas de absorção dos estiramentos alifáticos e do ânion carboxilato, enquanto que no Latossolo, devido ao maior teor de argila, as bandas de absorção da matéria orgânica foram pouco perceptíveis. No espectro da amostra oxidada e no resíduo da solo após extração das substâncias húmicas foi possível observar ainda bandas da matéria orgânica, o que indica que uma parte da matéria orgânica é resistente à oxidação e que parte dela é constituída por humina (respectivamente) Os espectros de FTIR obtidos para as frações humificadas da matéria orgânica mostraram que os ácidos húmicos e a humina são compostos principalmente por estruturas alifáticas e aromáticas, enquanto que nos ácidos fúlvicos os grupos carboxílicos e de carbohidratos são mais abundantes. Os resultados obtidos mostraram que a análise da matéria orgânica no solo in situ por DRIFT é limitada pela mineralogia e textura do solo, sendo mais adequada para solos com baixo teor de argila.
O objetivo desse trabalho foi investigar a capacidade de armazenagem de C e N em perfis com horiz... more O objetivo desse trabalho foi investigar a capacidade de armazenagem de C e N em perfis com horizontes Húmicos e Hísticos, a estabilidade do estoque desses elementos e a origem da MOS nesses solos. Amostras foram coletadas em solos de diferentes profundidades em uma topossequência sob Floresta Ombrófila mista na bacia sedimentar de Curitiba / PR na APA do Iraí. Foram determinados os estoques de C e N e a assinatura isotópica de 13C por analisador elementar acoplado a espectrômetro de massas. A composição química da MOS foi avaliada por 13C RMN CP/MAS e pelas técnicas de Py-GC/MS e Py-CSIA. O estoque total estimado para a APA Iraí foi de 4,2 x 106 Mg C, o que supera em duas vezes os valores usualmente observados para outras áreas de solos altomontanos no PR. Os resultados indicam que no Latossolo a MOS é originária predominantemente da vegetação atual (C3) sobre o solo. Já no Gleissolo e no Organossolo a MOS é originária principalmente de uma vegetação do tipo C4 (gramíneas). Possivelmente, nesses dois solos as condições de saturação promovem a estabilização da MOS mais antiga, enquanto a MOS oriunda da vegetação atual sofre ciclagem mais intensa.Peer Reviewe
Poster presentado en la Session I • September 21, 2015 en el 5th International Symposium on Soil ... more Poster presentado en la Session I • September 21, 2015 en el 5th International Symposium on Soil Organic Matter (SOM 2015) Goettingen (Germany) 20-24 Semptember (2015)Peer Reviewe
Burleigh Dodds series in agricultural science, Nov 8, 2022
LADEe Latin American Developments in Energy Engineering, Jun 3, 2023
The abundance of organic waste generated by agro-industrial activities leads to the need to find ... more The abundance of organic waste generated by agro-industrial activities leads to the need to find alternatives for adequate destinations for these. Composting is the most viable alternative due to its low cost, ease of operation and generation of a product with the possibility of economic exploitation. The objective of this work was to present the dynamics of the composting process in an organic waste processing plant in the municipality of Montenegro, RS, Brazil, as well as to present the results of chemical analyzes for the quantification of humic substances contained in the leachate resulting from the composting process. The results of the leachate revealed that it has high levels of humic substances (humic acids between 12.2 and 30.7%, fulvic acids between 12.2 and 45.5%) significantly higher than those found in the literature (9%). Leachate has humic characteristics desired for the preparation of a commercial product for use in agriculture and can be configured as an interesting extra income alternative for the economic health of the enterprise.
Revista Brasileira De Ciencia Do Solo, 2022
Bases are chemical species that donate electrons, accept protons, or release hydroxyls (OH-) in a... more Bases are chemical species that donate electrons, accept protons, or release hydroxyls (OH-) in aqueous solution. In Soil Science, "base saturation", "exchangeable bases" or "basic cations" has been widely used to distinguish Ca 2+ , Mg 2+ , Na + , and K + from H + and Al 3+ cations. This terminology is confusing since none of these cations are truly a base in chemistry sense. However, in the absence of the proposition of a correct term, the term "base saturation" remains in use nowadays, causing confusion among students, professionals, and even among professors and researchers in Soil Science, as it leads to the erroneous interpretation that the soil acidity can be corrected by adding these cations to the soil. Here, we present the historical background of this nomenclature and a theoretical foundation that justifies the abolition of the use of these terms in Soil Science. We consider that the most correct is to call it "Ca-Mg-K-Na saturation", which, despite being long, would refer directly and without any misinterpretation of the terminology. In Soil Fertility, the "base saturation" is often calculated only as a function of the sum of Ca, Mg, and K, since the Na content is negligible in most tropical and subtropical soils. Thus, one could use the term "Ca-Mg-K saturation". Likewise, it is also suggested to abolish the use of the term "sum of bases" and use the term "sum of Ca-Mg-K" or "sum of Ca-Mg-K-Na" instead when necessary.
Soil & Tillage Research, Oct 1, 2023
EGUGA, Apr 1, 2009
Atrazine is a widely used herbicide on corn and sugar cane plantations, which, along with soybean... more Atrazine is a widely used herbicide on corn and sugar cane plantations, which, along with soybeans, are the most productive crops in Brazil and are responsible for 36.5% of the annual national consumption of herbicides. Mesotrione is a new herbicide registered in the last years used for controlling weeds in corn plantations as a tentative substitution for atrazine. After its
Os ácidos húmicos diferem fundamentalmente dos ácidos fúlvicos por apresentar massa molar média, ... more Os ácidos húmicos diferem fundamentalmente dos ácidos fúlvicos por apresentar massa molar média, maior grau de aromaticidade e menor teor de oxigênio. Estas diferenças químicas refletem-se na maior solubilidade e no poder complexante superior verificado nos ácidos fúlvicos, influenciando diretamente a retenção e mobilidade de cátions no solo. O objetivo do presente trabalho foi comparar a composição de ácidos húmicos e fúlvicos. Ácidos húmicos (AH) e fúlvicos (AF) foram extraídos de uma amostra de lodo orgânico e submetidos à análise de Infra-Vermelho (IV), à espectroscopia UV/VIS e à análise termogravimétrica (TG) Os espectros de IV de AH e os de AF
Scientia Agricola, Oct 1, 2007
Organic carbon (C) concentration evaluated by the Walkley-Black method, and total nitrogen (N) co... more Organic carbon (C) concentration evaluated by the Walkley-Black method, and total nitrogen (N) concentration determined by Kjeldahl method, were compared with corresponding results of C and N concentrations obtained through the dry combustion method (Elementar Vario EL analyzer), using samples of ten soil layers down to the depth of 107.5 cm of a kaolinitic Typic Paleudult (220-418 g clay kg-1 along the profile) subjected to no-till cropping systems [fallow bare soil, pigeon pea (Cajanus cajan L. Millsp.) plus maize, and lablab (Lablab purpureum L. Sweet) plus maize]. A close correlation (R 2 ≥ 0.96) was observed between the C results of the Walkley-Black and dry combustion methods, but a correction was suggested to be applied to C results of Walkley-Black (C = 1.05C W.Black + 0.47). A close correlation (R 2 ≥ 0.96) was also found between results of Kjeldahl-N and dry combustion-N, but no correction was necessary to be applied. The relationships between results of Walkley-Black and dry combustion and between results of Kjeldahl and dry combustion did not change among soil samples from different management systems, in disagreement to findings of a previous study where results of analytical C recovery were influenced by samples from different managements, supposedly because changes in lability or recalcitrance of organic matter might have affected the wet combustion reactions. A poor correlation (R 2 = 0.42) was found between the C:N ratios based on Walkley-Black and Kjeldahl analysis and the C:N ratios based on dry combustion analysis. The methods for C and N determination did not affect the interpretation of the effects of management systems on soil C and N stocks.
Water Air and Soil Pollution, Aug 1, 2019
Successive applications of pig manure increase Cu and Zn contents in soils and may cause toxicity... more Successive applications of pig manure increase Cu and Zn contents in soils and may cause toxicity to plants. However, plants may have defense strategies that reduce Cu and Zn availability in rhizosphere soil. The study aimed to evaluate growth of white oats (Avena sativa) and Cu and Zn availability in rhizosphere soil subjected to long-term applications of pig slurry (PS) and pig deep litter (PL). The study was carried out with samples of a Typic Hapludalf soil from an 11-year experiment with annual fertilization of 180 kg N ha −1 as pig slurry (PS180) and pig deep litter (PL180) and a control (C) treatment. White oats were grown in pots with soil collected at 0.0-0.10 m depth. Thirty-five and 70 days after emergence (DAE), rhizosphere (RS) and bulk soil (BS) were analyzed to determine Cu and Zn availability. Plant growth, tissue Cu and Zn concentration, and content (concentration X dry weight) were measured. The application of pig manure for 11 years increased available soil Cu and Zn, as well as tissue concentration and content. Dry matter yield and
Environmental Geochemistry and Health, Apr 25, 2020
This study aims to evaluate available Cu and Zn levels in soil and related in soil organic matter... more This study aims to evaluate available Cu and Zn levels in soil and related in soil organic matter (SOM) fractions (fulvic acids-FA, humic acids-HA, and humins-HU) after 10 years of application of pig slurry (PS) and pig deep litter (PL). Soil samples were collected from an experiment with black oat/corn succession under no-tillage in southern Brazil. The treatments consisted of fertilization of 90 and 180 kg N ha-1 applied as PS and PL from 2002 to 2012 and a control treatment without any fertilization. SOM chemical fractionation was performed in airdried samples. Copper and Zn concentrations were analyzed in soil (total, EDTA-and CaCl 2-extracted) and in SOM fractions. The amount of Cu and Zn (in mol) related to each fraction of SOM (Cu/C and Zn/C
Revista Brasileira De Ciencia Do Solo, 1997
The aim of this study was to evaluate the humification process in organic sludges resultant from ... more The aim of this study was to evaluate the humification process in organic sludges resultant from cellulose production, and to characterize the decomposition products. Humic substances (SH) were extracted from samples collected periodically from six different biodigestors during nine months with 0.5 mol L -1 NaOH solution, and three fractions were separated: the insoluble fraction, IN (insoluble in basic medium), the humic acid fraction, AH (soluble in basic but insoluble in acid medium), and the fulvic fraction, FF (soluble in basic as well as in acid medium). The contents of IN and AH were obtained by weighing the respective residues and that ofFF was obtained by difference. The following analyses were performed on the separated fractions: determination ofcontents of C, H and N by elemental analysis; determination of ash content by calcination during 4h at 750°C; calculation of E 4 /E 6 ratio from the W-VIS spectroscopy data, and the identification ofthe functional groups by infrared spectroscopy and solid state 13 C-Nuclear Magnetic Ressonance (NMR) (CP/MAS). Among the six digestion media, the addition ofprotein was the most effective in increasing the production ofhumic substances (AH+FF). The addition of aminoacids and of calcareous residue also stimulated the digestion. The AH fraction showed contents of C, H, N and O (calculated by difference) similar to those of soil humic acids, and the C/N ratio varied between 10 and 14. The functional groups identified by vibrational spectroscopy showed a typical composition of soil humic acids. Data from 13 C-NMR disclosed ca. 40% aliphatic and low carboxyl content both in AH and FF The values for H/C atomic ratio, always >1.51 in the AH, corroborated the NMR results. From the findings it is concluded that organic sludges generated humic substances, even though the humification process occurred in a biodigesto
Advances in Weed Science, 2022
This is an open-access article distributed under the terms of the Creative Commons Attribution Li... more This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided that the original author and source are credited.
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Papers by deborah pinheiro dick