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G?nese, caracteriza??o e compara??o de m?todos anal?ticos de solos de natureza calc?ria do Grupo Bambu?, no estado do Tocantins / Genesis, characterization and comparison of analytical methods for calcareous soils from Group Bambu?, in the state of TocantinsMARANH?O, Deyvid Diego Carvalho 20 March 2014 (has links)
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Previous issue date: 2014-03-20 / CAPES / Calcareous soils represent a significant portion of agricultural areas of the planet; commonly have high contents of calcium, magnesium, carbonates, associated with high pH values. In general, although there is little information about their attributes, they are located in areas with great potential for agricultural use. This study aimed to evaluate aspects involved in the genesis of calcareous soils of the Bambu? Group in the municipalities of Lavandeira and Aurora, southeast of Tocantins state, using morphological, physical, chemical and mineralogical attributes, and to compare methods for analytical evaluation ofthis soil attributes. Mostly, these soils havea low degree of pedogenetic development, highlighting the pedogenic processes of melanization and calcification, as well as high levels of silt fraction, which are related to the occurrence of siltstones layers associated with the limestone. From the evaluations, it is suggested that the carbonate character or calcic horizon must be included in the large group level in the class of Luvissolos H?plicos in the Brazilian System of Soil Classification. In this study, the profil P4 of toposequence T2 showed high calcium carbonate content, but were classified as "?rtico" respectively; thus omitting a feature of great importance in the management aspect. This attribute should be emphasized in the classification, since it influences the soil pH, available phosphorus content and micronutrients. The use of the suffix "r" should be reviewed in the Manual for Soil Description and Sampling in the Field, as this suffix has been used exclusively to the horizon and / or layer C, omitting this feature to other horizons, as it is featured in profile P1 of toposequence T2. As for the analytical methods, the phosphorus (P) determination more efficiently to calcareous soilsuses a buffered alkaline solution extraction (Olsen et al., 1954), and the use of acidic nature extractors (Mehlich 1) may overestimate the values of available phosphorus. Moreover, the method for determining calcium carbonateequivalent, with the changes proposed by Donagemma et al. (2011), quantified higher concentrations of calcium carbonate (CaCO3), suggesting that other methods have underestimating the CaCO3 content of the samples. As for the particle size analysis of fine earth, the usage of sodium hydroxide as chemical dispersant was more efficient in determining the clay fraction, with better dispersion of this fraction compared to the sodium hexametaphosphate solution. In contrast, the method for organic carbon measurement proposed by Yeomans and Bremner (1988) was more efficient, when compared to the method of Donagemma et al. (2011), as shown by the values similar to the ones obtained from elemental analysis (CHNS-O) in samples pretreated with an acid solution. / Os solos calc?rios representam uma parcela significativa das ?reas agr?colas do planeta; comumente, apresentam elevados teores de c?lcio, magn?sio, carbonatos, associados a elevados valores de pH. De modo geral, embora haja poucas informa??es acerca de seus atributos, est?o em ?reas de grande potencial para a utiliza??o agr?cola. Esse estudo teve como objetivo avaliar aspectos envolvidos na g?nese de solos calc?rios do Grupo Bambu?, nos munic?pios de Lavandeira e Aurora, sudestedo estado do Tocantins, a partir de atributos morfol?gicos, f?sicos, qu?micos e mineral?gicos, bem como comparar m?todos anal?ticos para avalia??o de atributos desses solos. Majoritariamente, esses solos apresentaram baixo grau de desenvolvimento pedogen?tico, destacando-se os processos pedogen?ticos de melaniza??o e calcifica??o, al?m de elevados teores da fra??o silte, o que est? relacionado ? ocorr?ncia de l?minas de siltitos associadas ao calc?rio. A partir das avalia??es realizadas, sugere-se que o car?ter carbon?tico ou horizonte c?lcico devem ser inclu?dos no n?vel de grande grupo na classe dos Luvissolos H?plicos do Sistema Brasileiro de Classifica??o de Solos. Neste estudo, os perfis P1 e P4 da topossequ?ncia T2 apresentaram elevados teores de carbonato de c?lcio, por?m foram classificados como ?L?tico? e ??rtico?, respectivamente, omitindo-se essa caracter?stica que ? de grande relev?ncia no aspecto de manejo. Esse atributo deve ser ressaltado na classifica??o, visto que ? determinante do pH, teor de f?sforo e de micronutrientes dispon?veis. A utiliza??o do sufixo ?r? deve ser revista no Manual de Descri??o e Coleta de Solo no Campo, pois esse sufixo tem sido de uso exclusivo para o horizonte e/ou camada C, omitindo essa caracter?stica para os demais horizontes, assim como caracterizado no perfil P1 da topossequ?ncia T2. Quanto aos m?todos anal?ticos, o m?todo de determina??o de f?sforo (P) mais eficiente para solos calc?rios faz uso de uma solu??o extratora alcalina tamponada (Olsen et al., 1954), sendo que a utiliza??o de extratores de natureza ?cida (Mehlich-1) pode superestimar os teores de P dispon?vel. Por outro lado, o m?todo de determina??o de carbonato de c?lcio equivalente, com altera??es da metodologia proposta pela Donagemma et al. (2011), quantificou maiores teores de carbonatos de c?lcio (CaCO3), sugerindo que os demais m?todos t?m subestimando os teores de CaCO3 das amostras. Quanto ? an?lise granulom?trica da terra fina, o hidr?xido de s?dio, como dispersante qu?mico, mostrou-se mais eficiente na determina??o da fra??o argila do solo, por ter proporcionado maior dispers?o dessa fra??o, quando comparado ? solu??o de hexametafosfato de s?dio. Em contrapartida, o m?todo de determina??o de carbono org?nico proposto por Yeomans e Bremner (1988) mostrou-se mais eficiente em compara??o ao m?todo da Donagemma et al. (2011), apresentando valores mais pr?ximos dos obtido na an?lise elementar (CHNS-O) em amostras pr?-tratadas com solu??o ?cida.
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Caracteriza??o dos solos e avalia??o da aptid?o agr?cola das regi?es produtoras de vinhos finos de altitude de Santa Catarina / Soil characterization and evaluation of agricultural potential of the regions producing fine wines in Santa Catarina altitudeDORTZBACH, Denilson 02 June 2016 (has links)
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Previous issue date: 2016-06-02 / CAPES / The soils of fine wines producing regions of Santa Catarina State, has particular altitude characteristics resulting from its lithology and high levels of organic matter. That differentiate the soil of the major producing regions of the world wine. The study was conducted in the regions of west and mountain through Santa Catarina, covering over 80 % of the properties where descriptions and collections of 38 modal profiles and vineyards spread over 45 farms were carried out. The objectives were: a) To characterize the distribution and interaction of soil formation factors and chemical weathering rates; b) evaluate and quantify the carbon, humic fractions in the profiles and ?13C in surface horizons of Cambisols; c) To characterize physical and chemically soils of the vineyards; d) To evaluate the agricultural potential through different methods, with subsequent adaptation of the System for Agricultural Assessment of land for the grape culture in addition to formulating a proposal for zoning for the wine industry of the state. The results indicate that pedogenetic soil was strongly influenced by the source material, weather and terrain. Cluster analysis separated by the similarity the soil profiles in three different groups. Predominate classes Cambisols and Nitossols. Humic substances allowed to discriminate the taxonomic orders of soil and showed ?13C in soil with the humic, little change in isotopic signature, and soils with moderate. The observed changes were derived from C3 and C4 plants crops. The vineyards have similar chemical properties, and thus can be grouped in a single region for a determination of Geographical Indication. As for agricultural suitability evaluating different methods indicated that the evaluated profiles have low agricultural aptitude for annual crops. Therefore, it was proposed an adaptation of the evaluation system of agricultural suitability of the land for the growing of vines, taking into account specific conditions of altitude in the SC state. Allied to this, the drafting of the zoning proposal is an important tool for the implementation of new vineyards. / Os solos das regi?es produtoras de vinhos finos de altitude do estado de Santa Catarina apresentam caracter?sticas particulares decorrentes da sua litologia e dos elevados teores de mat?ria org?nica, que os diferenciam dos solos das grandes regi?es produtoras de vinho do mundo. O estudo foi realizado nas regi?es do meio oeste e serrana de Santa Catarina, abrangendo mais de 80 % das propriedades, onde foram realizadas descri??es e coletas de 38 perfis modais e em vinhedos espalhados em 45 propriedades rurais. Os objetivos foram: a) caracterizar a distribui??o e a intera??o dos fatores de forma??o dos solos e a taxa de intemperismo qu?mico; b) avaliar e quantificar os teores de carbono, fra??es h?micas nos perfis e o ?13C em horizontes superficiais de Cambissolos; c) caracterizar f?sica e quimicamente os solos dos vinhedos; e d) avaliar a aptid?o agr?cola atrav?s dos diferentes m?todos, com posterior adapta??o do Sistema de Avalia??o Agr?cola das Terras, para a cultura da videira, al?m de formular proposta de zoneamento para a vitivinicultura do estado. Os resultados indicam que a pedog?nese dos solos foi fortemente influenciada pelos fatores material de origem, clima e relevo. A an?lise do agrupamento separou pela similaridade os perfis de solo em tr?s grupos distintos. Predominam as classes de Cambissolos e Nitossolos. As subst?ncias h?micas permitiram discriminar as ordens taxon?micas de solos e o ?13C revelando pouca altera??o na assinatura isot?pica nos solos com horizonte A h?mico. Nos solos com A moderado foram observadas altera??es decorrentes de mudan?as nas coberturas (plantas C3 ou C4). As ?reas dos vinhedos apresentam atributos qu?micos similares, podendo ser agrupadas em uma regi?o ?nica para eventual determina??o de Indica??o Geogr?fica. Quanto ? aptid?o agr?cola, ? avalia??o atrav?s de m?todos usuais na literatura resultou em classes que indicam baixa aptid?o para culturas anuais. Diante disto, foi proposta adapta??o do sistema de avalia??o da aptid?o agr?cola das terras, para a cultura da videira, considerando condi??es especificas de altitude no estado de SC e associada ? elabora??o de uma proposta de zoneamento para a implanta??o de novos vinhedos.
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Fracionamento da mat?ria org?nica e caracteriza??o dos ?cidos h?micos e sua utiliza??o no Sistema Brasileiro de Classifica??o de Solos. / Organic matter fractionating and characterization of humic acids and its use in the Brazilian System of Soil Classification.Fontana, Ademir 03 April 2009 (has links)
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Previous issue date: 2009-04-03 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The importance of soil organic matter in pedology and especially soil classification studies
can be substantiated by the use of attributes such as organic carbon content, degree of organic
matter decomposition from the fibers content. Recent studies in Brazil with humic substances
report establishment of standards that could be used to differentiate soil horizons (diagnostic
attributes), soil horizon classification and the relationship with properties that connote soil
fertility. This study had as objectives: to characterize humic substances and humic acids of
different diagnostic soil horizons of Brazilian soils; b) to propose the utilization of attributes
related to humic substances in the characterization of the lower hierarchical levels (family and
series) of the Brazilian System of Soil Classification (SiBCS). The soil material utilized
material from 169 diagnostic horizons or epipedons, identified as: 13 O histic, 30 H histic,
42 A mollic, 39 A umbric, and 45 B spodic horizons. In these horizons there were evaluated
the chemical properties: TOC, pH, H+, SB (sum of bases), CEC and V% (base saturation);
physical properties: sand, silt and clay contents; quantitative fractionating of humic
substances: fulvic acid fraction (C-FAF), humic acid fraction (C-HAF) and humin (C-HUM),
C-HAF/C-FAF, C-AE/C-HUM, and C-AE/COT ratio (C-AE = C-FAF + C-HAF), and the
%FAF, %HAF, %HUM and %AE. In the purified humic acid (HA) spectroscopic analyses
were performed on visible and infrared regions, elemental composition and termogravimetric
analyses; in addition to that the alkaline extract (AE) was analyzed by spectroscopy on visible
region. The quantitative fractionating of humic substances showed differential distribution
between the types of diagnostic soils horizons, highlighting the O and H histic horizons,
where the predominance of humin showed average around 53% and 39%, respectively, and
followed by humic acids. Also, for the H histic horizon there were high values of the
C-HAF/C-FAF ratio (average of 5.6). On the mollic epipedon it was observed predominance
of humin with average around 71%, and low values of C-AE/C-HUM ratio (average of 0.2),
and on the umbric epipedon humin predominance averaging 47%, followed by humic acids.
On the spodic horizon there was predominance of fulvic and humic acids with average around
30% and 44%, respectively. On this horizon, the values of the C-HAF/C-FAF ratio were high,
with average around 9.9 (most of them higher than 1.0), and the C-AE/C-HUM ratio averaged
16.5 (majority higher than 2.0). The evaluation of variables related to visible and infrared
spectroscopic, elemental composition and termogravimetric of HA, and visible region for AE,
showed similar characteristics and absence of a pattern independent ly of soils genesis.
According to the distribution of humic substances the following differential characteristics
were proposed to the SiBCS: Stable Organic Matter (surface mineral horizons)
C-AE/C-HUM = 0.5, Iluvial Organic Matter (subsurface mineral horizons) -
C-AE/C-HUM = 2.0, and Leaching Potential (system or soil) - C-HAF/C-FAF and
C-AE/C-HUM = 1.0. Also, the establishment of classes according to humic substances was
efficient to identify distinct groups based on their chemical properties. This result validates
the proposal of using these variables to classify these horizons on the family and series levels,
and contribute to structure the SiBCS in the lower hierarchical levels (5th and 6th). / A import?ncia da mat?ria org?nica do solo nos estudos de pedologia e em especial na
classifica??o de solos pode ser constatada pela utiliza??o de atributos como os teores de
carbono org?nico e grau de decomposi??o da mat?ria org?nica a partir do teor de fibras.
Alguns trabalhos desenvolvidos recentemente no Brasil com subst?ncias h?micas em solos
buscaram estabelecer padr?es que poderiam ser utilizados na separa??o de horizontes
(atributo diagn?stico), classifica??o dos horizontes ou mesmo rela??es com propriedades
ed?ficas que conotam fertilidade dos solos. Este trabalho teve como objetivos: caracterizar
diferentes horizontes diagn?sticos de solos por meio das subst?ncias h?micas e dos ?cidos
h?micos; e propor o uso de atributos relacionados ?s subst?ncias h?micas na categoriza??o
dos n?veis hier?rquicos inferiores (fam?lia e s?rie) do SiBCS. Foram utilizados materiais de
solo de 169 horizontes diagn?sticos, sendo: 13 O h?stico, 30 H h?stico, 42 chernoz?mico,
39 A h?mico, 45 B esp?dico. Foram avaliadas as propriedades qu?micas: COT, pH, SB, H+,
Al3+, CTC e V%; propriedades f?sicas: areia, silte e argila; fracionamento quantitativo das
subst?ncias h?micas: fra??o ?cidos f?lvicos (C-FAF), fra??o ?cidos h?micos (C-FAH) e
fra??o humina (C-HUM), rela??es C-FAH/C-FAF, C-EA/C-HUM e C-EA/COT (C-EA =
C-FAF + C-FAH) e a %FAF, %FAH, %HUM, % EA. Em ?cidos h?micos (AH) purificados
foram realizadas an?lises espectrosc?picas na regi?o do vis?vel e infravermelho, composi??o
elementar e termogravim?trica; al?m de, no extrato alcalino (EA) an?lise espectrosc?pica na
regi?o do vis?vel. O fracionamento quantitativo das subst?ncias h?micas apresentou
distribui??es diferenciadas entre os tipos de horizontes diagn?sticos de solos, destacando-se
no O h?stico e H h?stico o predom?nio da humina com m?dia de 53% e 39%, respectivamente,
seguido dos ?cidos h?micos e ainda para o ?ltimo, altos valores da rela??o C-FAH/C-FAF
(m?dia de 5,6). No A chernoz?mico observou-se o predom?nio absoluto da humina com m?dia
de 71% e baixos valores da rela??o C-EA/C-HUM (m?dia de 0,2) enquanto no A h?mico
houve predom?nio da humina (m?dia de 47%), seguida dos ?cidos h?micos. No B esp?dico o
predom?nio dos ?cidos f?lvicos e h?micos com m?dia de 30% e 44%, respectivamente, e altos
valores da rela??o C-FAH/C-FAF com m?dia de 9,9 (maioria superiores 1,0) e C-EA/C-HUM
com m?dia de 16,5 (maioria superiores 2,0). Pela avalia??o das vari?veis relacionadas ?
espectroscopia do vis?vel e infravermelho, composi??o elementar e termogravimetria dos AH,
e na regi?o do vis?vel para o EA, observou-se caracter?sticas semelhantes e aus?ncia de padr?o
diferencial independente da g?nese dos solos. Com base na distribui??o das subst?ncias
h?micas foram feitas as seguintes propostas de caracter?sticas diferenciais no SiBCS: Mat?ria
Org?nica Est?vel (horizontes minerais superficiais) - C-EA/C-HUM = 0,5, Mat?ria Org?nica
Iluvial (horizontes minerais subsuperficiais) - C-EA/C-HUM = 2,0 e, Potencial de Lixivia??o
(sistema ou solo) - C-FAH/C-FAF e C-EA/C-HUM = 1,0. O estabelecimento de classes com
os valores das subst?ncias h?micas tamb?m foi eficiente para individualizar grupos pela
compara??o das propriedades qu?micas, o que valida a proposta de utiliza??o dessas vari?veis
para a classifica??o desses horizontes nos n?veis de fam?lia ou s?rie e podem contribuir para a
estrutura??o do SiBCS nos n?veis hier?rquicos inferiores (5? e 6?).
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