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Influence of Humic Acids on the Migration Behavior of Radioactive and Non-Radioactive Substances Under Conditions Close to Nature -Synthesis, Radiometric Determination of Functional Groups, Complexation-Nitsche, Heino, Heise, Karl-Heinz, Bernhard, Gert, Schmeide, Katja, Pompe, Susanne, Bubner, Marianne 31 March 2010 (has links) (PDF)
The interaction behavior of humic acids with uranium(VI) and the influence of humic substances on the migration behavior of uranium was investigated. A main focus of this work was the synthesis of four different humic acid model substances and their characterization and comparison to the natural humic acid from Aldrich. A radiometric method for the determination of humic acid functional groups was applied in addition to conventional methods for the determination of the functionality of humic acids. The humic acid model substances show functional and structural properties comparable to natural humic acids. Modified humic acids with blocked phenolic OH were synthesized to determine the influence of phenolic OH groups on the complexation behavior of humic acids. A synthesis method for 14C-labeled humic acids with high specific activity was developed. The complexation behavior of synthetic and natural humic acids with uranium(VI) was investigated by X-ray absorption spectroscopy, laser-induced fluorescence spectroscopy and FTIR spectroscopy. The synthetic model substances show an interaction behavior with uranium(VI) that is comparable to natural humic acids. This points to the fact that the synthetic humic acids simulate the functionality of their natural analogues very well. For the first time the influence of phenolic OH groups on the complexation behavior of humic acids was investigated by applying a modified humic acid with blocked phenolic OH groups. The formation of a uranyl hydroxy humate complex was identified by laserspectroscopic investigations of the complexation of Aldrich humic acid with uranium(VI)at pH 7. The migration behavior of uranium in a sandy aquifer system rich in humic substances was investigated in column experiments. A part of uranium migrates non-retarded through the sediment, bound to humic colloids. The uranium migration behavior is strongly influenced by the kinetically controlled interaction processes of uranium with the humic colloids. The influence of humic acids on the sorption of uranium(VI) onto phyllite was investigated in batch experiments using two different humic acids. The uranium(VI) sorption onto the rock phyllite is influenced by the pH-dependent sorption behavior of the humic acids.
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Aqueous photochemistry of syringic acid as a model for the environmental photochemical behaviour of humic substancesDallin, Erin 09 October 2007 (has links)
The aqueous photochemistry of 4-hydroxy-3,5-dimethoxybenzoic acid (syringic acid) has been studied as a model humic substance in order to better understand the reactions that compounds of this type undergo in the natural environment. Syringic acid was chosen since it has been identified as a component of humic substances in the environment and bears many of chemical moieties found in structures of this type. In addition, there has been speculation that humic substances are responsible for some of the production of halomethanes that are released into the environment. Photolysis of these compounds in marine and estuarine waters may be responsible for the release of halomethanes which are known stratospheric ozone depleters. Photochemical product studies of syringic acid and related compounds along with UV-Vis spectrometry, laser flash photolysis and membrane introduction mass spectrometry were carried out in aqueous solutions to study its photochemical transformations. Syringic acid was found to form methanol at a 0.01 quantum yield upon its photolysis in basic solution. Other major photoproducts included 3-methoxygallic acid and 3,5-dimethoxybenzoic acid. Chloromethane was identified as a minor photoproduct in chloride enriched solution by following its production via membrane introduction mass spectrometry. The proposed mechanism for the formation of these photoproducts involves an initial photoprotonation of the benzene ring, resulting in a carbocation that can facilitate the nucleophilic attack by water or chloride, to produce methanol or chloromethane, respectively. The formation of 3,5-dimethoxybenzoic acid is via a novel pathway that involves the loss of the hydroxy group from the aromatic ring after the photoprotonation.
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Prophylaktischer und therapeutischer Einsatz von Braunkohle-Huminstoffen in der Nutz- und ZierfischzuchtHeidrich, Stefan 04 August 2005 (has links) (PDF)
F�r die Therapie und Prophylaxe von Fischkrankheiten stehen nur wenige geeignete und zugelassene Medikamente zur Verf�gung. Daher kommt der Suche nach wirksamen und f�r Tier, Verbraucher und Umwelt sicheren Alternativen in der Fischhaltung eine besondere Bedeutung zu. �ber positive Effekte beim oralen Einsatz von Huminstoffen an landwirtschaftlichen Nutztieren, Zootieren und Heimtieren liegen eine Vielzahl von Berichten vor. Deshalb sollten in der vorliegenden Studie Huminstoffe (HS) in der �u�erlichen Anwendung bei Zierfischen und in der oralen Verabreichung �ber das Futter bei Nutzfischen n�her untersucht werden. Dazu wurden zwei Versuche (B I: Dauer 4 Tage; B II: Dauer 12 Tage) an Goldfischen (Carassius auratus) unter teichwirtschaftlichen Bedingungen, zwei Aufzuchtversuche (F I: Kv bis K3, Dauer: 1.000 Tage: F II: K0 bis K1, Dauer: 150 Tage) an Karpfen (Cyprinus carpio) in der Teichwirtschaft und ein Aufzuchtversuch (F III: vorgestreckte Brut bis 30 g Lebendmasse, 166 Tage) an Regenbogenforellen (Oncorhynchus mykiss) unter Laborbedingungen durchgef�hrt. Als Versuchsparameter dienten Mortalit�t und Morbidit�t, Wachstum und Futteraufwand in den Aufzuchtversuchen, pathologisch anatomische (einschlie�lich histologischer Befunde in B I und F II), parasitologische, bakteriologische und virologische Kriterien. Die Wasserqualit�t wurde regelm��ig ermittelt. In den Versuchen B I und B II wurde eine 10%ige Na-Humat-L�sung (HS vom Typ WH 67 SNa der Fa. Pharmawerk Weinb�hla) dem H�lterungswasser so zugesetzt, dass eine Na-Humat-Konzentration von 10 mg L-1 entstand. Zweij�hrige, multifaktoriell erkrankte Goldfische (B I: N=2 x 322, B II: N=2 x 100) wurden dem Na-Humat-Bad t�glich f�r die Dauer einer Stunde (B I) bzw. von 1,5 bis 2 Stunden (B II) ausgesetzt. Die HS-Badehandlungen f�hrten in beiden Versuchen zu einer Senkung der Verluste (Mortalit�tsrate in B I: 0,6 versus 4,7 %, p<0,0005; B II: 8 versus 16 %, p<0,05). Bei Versuchsende war in den Versuchsgruppen (Na-Humat-Bad) der Gesundheitszustand, beurteilt nach �u�erlich sichtbaren Ver�nderungen an Haut, Flossen und Kiemen, deutlich verbessert (B I: p<1�10-16; B II: p<0,001). So waren (Signifikanzangaben nur f�r B II) vor allem H�morrhagien der Haut und der Flossen (p<0,05), Flossenrand- und Kiemennekrosen (p<0,05) sowie akute Kiemenentz�ndungen (p<0,02) verringert. Die Badebehandlungen bewirkten weiter eine geringere Auspr�gung integument�rer Mykosen der Haut, Flossen und Kiemen durch Pilze der Gattung Saprolegnia (p<0,05). Der Befall von Haut und Kiemen mit vorrangig protozo�ren Ektoparasiten konnte insgesamt ebenso vermindert werden (p<0,01) wie der Befall der Kiemen mit Ichthyophthirius sp. (p<0,05). Aus der beobachteten Milderung von Krankheitssymptomen umweltbedingter, bakterieller, ektoparasit�rer und mykotischer Genese nach Na-Humat-B�dern bei Goldfischen kann auf einen gewebeprotektiven, antiphlogistischen, antimykotischen und antiparasit�ren Effekt der Na-Humat-Behandlung geschlossen werden. In der Aufzucht von Karpfen (F I) und Regenbogenforellen (F III) wurden dem Futter 5 % Humocarb, formuliert� (HS vom Typ WH 67 A), im Karpfenversuch F II 5 % Cellu-Ligno-Karbon-Isolat (HS vom Typ WH 67 G, beide Produkte: Fa. Pharmawerk Weinb�hla) zugesetzt. In F I und F III wurde ein gleiches pelletiertes Alleinfutter f�r Forellen, in F II ein pelletiertes Alleinfutter f�r Karpfen eingesetzt. In Versuch F I (Besatzdichte der beiden Teiche (0,2 ha) jeweils 35.000 Kv ha-1) wiesen die Karpfen der Versuchs- gegen�ber der Kontrollgruppe h�here mittlere K�rpermassen auf. Der Unterschied zwischen den Gruppen bewegte sich mit einer Ausnahme (zu geringer Stichprobenumfang) zwischen p<0,05 (65 versus 45 g, 114. Tag) und p<0,0001 (1.146 versus 855 g, Versuchsende 1000. Tag). Der um die HS-Aufnahme bereinigte Futteraufwand des ersten Versuchsjahres war durch HS um 34 % verbessert. Die Futterquotienten in der zweiten und dritten Aufzuchtperiode waren durch die subjektive Futterzumessung (Nichtber�cksichtigung zwischenzeitlicher Verluste) verf�lscht. In Versuch F II (Besatzdichten der 2 x 3 Teiche (0,25 ha) 20.000, 30.000 bzw. 40.000 K0 ha-1) erhielten die Br�tlinge �ber die ersten zwei Wochen kein zus�tzliches Futter (nur Naturnahrung), anschlie�end wurde Weizenschrot zugef�ttert, erst ab dem 63. Tag das Versuchs- bzw. Kontrollfutter f�r 87 Tage. Bei Versuchsende war in den Gruppen der h�chsten Besatzdichte die Mortalit�t durch HS um ca. 20 % verringert (p<0,0001). Die Abfischungsmassen waren bei geringer Besatzdichte ann�hernd gleich, bei mittlerer Besatzdichte war die Kontrollgruppe, bei h�chster Besatzdichte die Versuchsgruppe favorisiert (statistische Pr�fung wegen des Fehlens von Einzeldaten nicht m�glich). Der um die HS-Aufnahme bereinigte Futteraufwand war in den HS-Gruppen bei geringer bzw. h�chster Besatzdichte um 5 bzw. 17 % verringert. In beiden Versuchen, F I und F II, wurde eine deutliche Verringerung des Gehaltes der inneren Organe Leber, Niere und Milz an fakultativ pathogenen Aeromonas- und Pseudomonas spp. nachgewiesen (p<0,05). Bei der Aufzucht von Regenbogenforellen (F III; N=2 x 25) trugen die durch den HS-Zusatz bedingten Ver�nderungen der Konsistenz von Futter und Kot zur Verminderung einer starken Belagbildung (Bewuchs aus Algen und anderen Mikroorganismen) sowie zur Vermeidung von Wassertr�bungen in den Aquarien, insbesondere bei h�heren Temperaturen, bei. Signifikante Unterschiede in den Kenndaten von Wachstum und Futteraufwand wurden nicht beobachtet. Insgesamt gesehen erscheint aber der Zusatz von 5 % HS zum Futter als zu hoch gew�hlt, da sich der Futteraufwand in den HS-Gruppen bei Ber�cksichtigung der Gesamtfuttermenge (einschlie�lich des 5%igen HS-Zusatzes) �berwiegend ung�nstiger gestaltete. Die Effekte der oralen Applikation von 5 % HS im Futter sind damit weit weniger augenf�llig als nach �u�erlicher Anwendung. Die zootechnischen Parameter waren �berwiegend mehr oder weniger unver�ndert; allein in Versuch F I war die K�rpermasse in der HS-Gruppen im Versuchsverlauf (Stichproben und Abfischung) in der Regel signifikant h�her als in der Kontrollgruppe. Von k�nftiger Bedeutung f�r die Aquarienhaltung von Fischen (und m�glicherweise in Klein- und Zierteichen) k�nnte die beobachtete Wasserkl�rung und die Verminderung einer Belagbildung aus Algen und anderen Mikroorganismen sein. Eine intestinale Wirkung der HS wird insoweit unterstellt, als in beiden Karpfenversuchen die inneren Organe einen verminderten Befall an beweglichen Aeromonaden und Pseudomonaden aufwiesen. / Prophylactic and therapeutic use of brown coal-derived humic substances of the type WH 67 in finfish and ornamental fish farming On the market, there is a limited number of suitable and approved drugs available for therapy and prophylaxis of fish diseases. The search for alternatives which are both effective and safe for animals, consumers and environment is therefore of special importance. There are numerous reports on positive effects of orally administered humic substances (HS) on agricultural livestock, zoo animals and pets. Therefore, the present study aimed on effects of HS for both external treatment of ornamental fish and oral application on culture fish via feed. Two experiments on goldfish (Carassius auratus) (exp. B I: 4 days; exp. B II: 12 days), and on common carp (Cyprinus carpio) (exp. F I: 1,000 days, fry to 3-year-old fish ; exp. F II: 150 days, fry to young-of-the-year size) were carried out under pond culture conditions. Additionally, one experiment on rainbow trout (Oncorhynchus mykiss) was carried out in the laboratory (exp. F III: 166 days, fingerlings up to 30 g body weight). The following parameters were examined: mortality, morbidity, growth, feed conversion ratio (exp. F I, F II, F III only), pathologic anatomical criteria (including histological examination of fish from B I and F II), parasitological investigation, bacteriological and virological state. Water quality was regularly examined as well. In the experiments B I and B II, a 10% sodium-humate solution (type WH 67 SNa, Pharmawerk Weinb�hla) was mixed into the water until a sodium-humate concentration of 10 mg L-1 was reached. Two-year old, multifactorially diseased goldfish (B I: N= 2 x 322; B II: N= 2 x 100) were daily exposed to this water for a period of one (B I) and 1.5-2 (B II) hours, respectively. In both experiments the treatment of fish reduced in mortality (B I: 0.6 vs. 4.7 %, p<0.0005; B II: 8 vs. 16 %, p<0.05). Moreover, at the end of the experiments the sodium-humate treated fish showed a significantly improved health state (B I: p<10-16; B II: p<0.001) as indicated by externally visible changes of the skin, fins and gills. Specifically, reductions in haemorrhage of skin and fins (B II: p <0.05), and fin and gill necroses (B II: p<0.05), and gill inflammations (B II: p<0.02) were noted. Additionally, the sodium-humate treatment reduced integumental mucoses of skin, fins and gills (p<0.05) caused by Saprolegnia sp. The infection of skin and gills with protozoan parasites was reduced (p<0.01) as well. Ichthyophthirius sp. infections of the gills dropped significantly (p<0.05) in the treated fish groups as compared to the controls. Due to the observed mitigation of disease symptoms of environmental, bacterial, parasitic and fungal origin after a sodium-humate bath treatment of goldfish, a tissue protective, antiphlogistic, antimycotic and antiparasitic effect of sodium-humate can be concluded. For rearing of carp (F I) and rainbow trout (F III), 5 % Humocarb, formuliert� (type WH 67 A, Pharmawerk Weinb�hla) was mixed among the feed, while for the experiment F II 5 % Cellu-Ligno-Carbon-Isolat (type WH 67 G, Pharmawerk Weinb�hla) was added. In F I and F III a complete feed for trout was applied whereas for F II a complete feed for carp was used. In experiment F I (stocking density of both ponds 35,000 carp fry per ha) test fish revealed a higher mean body weight compared to the controls. With one exception (sample size to small), the difference between the groups was either significant (day 114: 65 vs. 45 g, p<0.05) or highly significant (day 1000: 1,146 versus 855 g, p<0.0001). The feed conversion ratio of the first experimental year (expurgated by HS-uptake) improved by 34 % due to HS application. Feed conversion ratio of the second and third year were falsified because of subjective feeding (which does not consider occurring losses). In experiment F II (stocking density of the 2 x 3 ponds (0,25 ha) were 20,000, 30,000 and 40,000 individuals per ha, respectively) no additional feed was given to the hatched fry during the first two weeks so that all the fish lived on natural feed items. Afterwards, bruised wheat grain was given until from day 63 either test or control feed was applied for a total of 87 days. At the end of the experiment, at the highest stocking density the mortality was significantly (p<0.0001) decreased by 20% in the test group supplied with HS. At low stocking density the total weight of fish at harvest was not different between the test and control group. However, at medium stocking density the average body weight was higher in the control whereas reverse conditions were observed at the highest stocking density (due to a loss of data no statistical analysis was possible). The feed conversion ratio (expurgated by the uptake of humic substances) was decreased in the test groups of low (5 %) and high (17 %) density. In both experiments (F I and F II) significantly reduced infections of the internal organs liver, kidney and spleen with potentially pathogenic Aeromonas and Pseudomonas spp. were detected. In the rainbow trout rearing (F III; N = 2 x 25), the HS-caused changes in consistency of feed and faeces impaired the formation of heavy algal films and large microorganism populations, and contributed to less turbid water turbidity in the aquaria, particularly at high temperatures. Significant differences in growth and feed conversion ratio could not be observed. In general, the addition of 5 % HS to the feed is regarded as being too high because the total amount of feed given (inclusive 5 % HS) is considered. The feed conversion ratio was higher in most of the HS-groups. Effects of oral application of 5 % HS in feed were thus less obvious than the bath treatment. Zootechnical parameters, in general, did not change. Merely in experiment F I the body weight of the HS-groups was significantly higher than that of the controls. In aquaria and small ponds used for ornamental fish breeding the observed cleaning of water and reduced formation of algal films and microorganism populations caused by HS could be of future importance. Intestinal effects of HS are assumed as internal organs revealed a reduced infection with both motile aeromonads and pseudomonads.
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Aqueous photochemistry of syringic acid as a model for the environmental photochemical behaviour of humic substancesDallin, Erin 09 October 2007 (has links)
The aqueous photochemistry of 4-hydroxy-3,5-dimethoxybenzoic acid (syringic acid) has been studied as a model humic substance in order to better understand the reactions that compounds of this type undergo in the natural environment. Syringic acid was chosen since it has been identified as a component of humic substances in the environment and bears many of chemical moieties found in structures of this type. In addition, there has been speculation that humic substances are responsible for some of the production of halomethanes that are released into the environment. Photolysis of these compounds in marine and estuarine waters may be responsible for the release of halomethanes which are known stratospheric ozone depleters. Photochemical product studies of syringic acid and related compounds along with UV-Vis spectrometry, laser flash photolysis and membrane introduction mass spectrometry were carried out in aqueous solutions to study its photochemical transformations. Syringic acid was found to form methanol at a 0.01 quantum yield upon its photolysis in basic solution. Other major photoproducts included 3-methoxygallic acid and 3,5-dimethoxybenzoic acid. Chloromethane was identified as a minor photoproduct in chloride enriched solution by following its production via membrane introduction mass spectrometry. The proposed mechanism for the formation of these photoproducts involves an initial photoprotonation of the benzene ring, resulting in a carbocation that can facilitate the nucleophilic attack by water or chloride, to produce methanol or chloromethane, respectively. The formation of 3,5-dimethoxybenzoic acid is via a novel pathway that involves the loss of the hydroxy group from the aromatic ring after the photoprotonation.
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Avaliação da biodegradabilidade de lixiviado de aterro sanitário consorciado com esgoto doméstico em um sistema biológico de tratamento de efluentesReque, Patrícia Tambosi January 2015 (has links)
O líquido denominado “lixiviado”, formado pela disposição de resíduos em aterros sanitários e lixões, apresenta composição complexa, dada principalmente pela presença de compostos orgânicos extremamente recalcitrantes. O tratamento consorciado deste efluente com esgotos domésticos em ETE’s municipais carece de estudos, tendo em vista que são líquidos com características diferentes. Neste trabalho foi avaliado o desempenho de um processo biológico de tratamento de efluentes, composto por 3 sistemas de banhados construídos (B1, B2 e B3) operados em paralelo, tratando a combinação de esgoto doméstico (90%) + lixiviado de aterro sanitário (10%), no que diz respeito a remoção de matéria orgânica de lenta degradação. Cada sistema foi composto por 4 leitos cultivados com as macrófitas emergentes Luziola peruviana e Typha latifolia, recebendo afluente proveniente de diferentes níveis de pré-tratamento, nomeadamente: B1 - processo biológico anaeróbio (UASB) seguido de aeróbio (CBR); B2 - processo biológico aneróbio (UASB) e B3 - sem prévio tratamento. Para tal, além das análises da matéria orgânica pelos parâmetros não específicos, foi também empregada análise de absorbância e fluorescência para analisar a presença de substâncias húmicas e o uso da respirometria para avaliação da DQO lentamente biodegradável. As eficiências médias de remoção dos sistemas B1, B2 e B3 foi de 97,4, 96,1 e 96,6 % para DBO5, 66,9, 70,9 e 80,6% para DQOT, 61,9, 69 e 62,8 % para DQOFil e de 60,3, 72,8 e 72 % para COT, respectivamente. A avaliação destes parâmetros permitiu inferir que o nível de pré-tratamento não influenciou na eficiência de remoção pelos sistemas de banhados. Os espectros de absorbância foram marcados por maior absorbância na região λ < 400 nm, com diminuição progressiva até 700 nm. A aplicação de coeficientes de absortividade indicaram a predominância de matéria orgânica dissolvida proveniente de esgoto doméstico, com pouca influência de SH’s. Nos espectros de emissão de fluorescência, o aparecimento de bandas na região de 450 nm indicou a presença de substâncias húmicas no afluente e efluente do sistema de banhados construídos, sem diferença significativa entre a intensidade de fluorescência emitida em 450 nm nas amostras analisadas, indicando que a substância em questão passou pelo tratamento sem ser degradada. Os resultados observados pela análise de fluorescência sincronizada do B1 apresentaram contribuição positiva do pré-tratamento (menor concentração de DQOFil) para o desempenho do banhado, devido a menor presença de ácidos húmicos no efluente. / The liquid known as "leachate", produced by the disposal of waste in landfills and dumps, has a complex composition, characterized mainly by the presence of recalcitrant organic compounds. Currently, there is a lack of knowledge regarding the co-treatment of leachate with municipal wastewater in WWTP's, considering that these are effluents with different characteristics. This study evaluated the performance of a biological treatment process of wastewater consisting of 3 constructed wetlands systems (B1, B2 and B3), operated in parallel, treating a combination of domestic sewage (90%) + landfill leachate (10 %). Each system was comprised of four beds cultured with emerging macrophytes Luziola peruviana and Typha latifolia receiving affluent from different levels of pre-treatment, namely: B1 - anaerobic biological process (UASB) followed by aerobic biological process (CBR); B2 - anaerobic biological process (UASB). B3 received the untreated effluents. The content of organic matter and humic substances was analyzed by non-specific parameters, absorbance and fluorescence methods. Respirometry test were conducted to evaluate the content of slowly biodegradable COD. The average removal efficiencies of systems B1, B2 and B3 was of 97.4, 96.1 and 96.6% for BOD5, 66.9, 70.9 and 80.6% for CODT, 61,9, 69 and 62.8% for CODFil and 60.3, 72.8 and 72% of TOC, respectively. The evaluation of these parameters allowed to infer that the level of pre-treatment did not influenced the removal efficiency by wetland systems. Absorbance spectra were marked by greater absorbance in the region λ = <400 nm with progressive decrease up to 700 nm. Absorptivity coefficients indicated the predominance of domestic sewage, with little influence of SH's. In the fluorescence emission spectra, the appearance of bands in the 450 nm region indicated the presence of humic substances in the influent and effluent of the constructed wetland systems without a significant. This indicates that the substance in question went through the treatment without being degraded. The results obtained by synchronous fluorescence analysis showed a positive contribution of the B1 pretreatment (lowest concentration DQOFil) to the observed performance due to less presence of humic acids in the effluent. The authors did not have success during evaluation of the slowly biodegradable COD using the method proposed before.
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Decomposição de resíduos vegetais de culturas de entressafra em sistema de semeadura direta e efeitos nos atributos químicos de um Latossolo e na produtividade de soja e milhoMarcelo, Adolfo Valente [UNESP] 27 June 2011 (has links) (PDF)
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marcelo_av_dr_jabo.pdf: 1194015 bytes, checksum: 68c9171ad52d863ef75fe8bb9b03c925 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Em sistema de semeadura direta, os resíduos das culturas de entressafra são utilizados para protegerem a superfície do solo dos agentes erosivos e promoverem a ciclagem de nutrientes. O objetivo desse trabalho foi avaliar o efeito de sequências de culturas na quantidade, qualidade, decomposição e liberação de nutrientes dos resíduos vegetais de culturas de entressafra, bem como a cobertura do solo proporcionada pelos resíduos, na fertilidade do solo, nas frações particulada e associada aos minerais de C, nas substâncias húmicas do solo e na produtividade de milho e soja cultivados no verão, em região de clima tropical. O experimento foi conduzido em Jaboticabal, SP (48°15’22’’ W e 21°18’58’’ S), em um Latossolo Vermelho eutrófico. O delineamento experimental foi em faixas, com três repetições. Os tratamentos foram constituídos pela combinação de três sequências de culturas de verão (rotação soja-milho, monocultura de milho e monocultura de soja) com sete culturas de entressafra (milho, sorgo, girassol, crotalária, guandu, nabo forrageiro e milheto). O experimento foi iniciado em 2002 e o presente estudo se refere aos anos agrícolas 2008/2009 e 2009/2010. Avaliaram-se as quantidades de matéria seca e acúmulo de N, P, K, Ca, Mg e S pelas culturas de entressafra, bem como a dinâmica de decomposição e liberação dos nutrientes, por meio da utilização de sacolas de decomposição, com os seguintes períodos de avaliação: 15, 30, 60, 120 e 180 dias. A cobertura do solo foi avaliada após o manejo e ao final de cada ano agrícola. Amostras de solo foram coletadas nas camadas 0-10, 10-20 e 20-30 cm de profundidade em duas ocasiões, antes da semeadura das culturas de entressafra, em março, e de verão, em outubro, nos anos de 2008 e 2009. As amostras de solo foram submetidas às análises químicas para determinação dos teores... / In no-tillage system, the offseason crops residues are expected to maintain the soil covered in order to control soil erosion and to promote the nutrients cycling. The objective of this study was to evaluate the offseason crops dry matter quality and production, soil cover, residues decomposition and nutrient release and their effects on soil fertility, C content of humic substances, particulate and mineral associated organic matter fractions and summer maize and soybean yield. A field experiment has been carried out on a Rhodic Eutrudox at Jaboticabal, SP, Brazil (48°15’22’’ W and 21°18’58’’ S). A randomized split-block design with three replications was used. The treatments were the combination of three summer crops sequences (soybean-corn rotation, monoculture of corn and monoculture of soybean) with seven offseason crops (maize, grain sorghum, sunflower, sunn hemp, pigeon pea, oilseed radish and pearl millet). The cultivations started in 2002 and this study is related to 2008/2009 and 2009/2010 growing seasons. The offseason crops dry matter production and N, P, K, Ca, Mg and S accumulations were evaluated at management moment. The period of time to measure the residue decomposition and the nutrient release was 15, 30, 60, 120 and 180 days, using litter bags. The soil cover was evaluated after the offseason crops management and at the end of each growing season. The soil was sampled at 0-10, 10-20 and 20-30 cm soil depths in two occasions, before the offseason crops sowing, at March, and before the summer crops sowing, at October, in 2008 and 2009. Total organic C, pH, P, K, Ca, Mg and H+Al were determined in each soil samples. The soil samples obtained on October at 0-10 cm were submitted for physical and chemical organic matter fractionation, for particulate, mineral-associated, humic acid, fulvic acid and humin C content determination. The summer monoculture... (Complete abstract click electronic access below)
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Interações entre íons Hg(II) e substâncias húmicas extraídas de diferentes solos da Bacia do Médio Rio Negro, AmazôniaBellin, Iramaia Corrêa [UNESP] 19 May 2006 (has links) (PDF)
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bellin_ic_dr_araiq.pdf: 1668200 bytes, checksum: bca88ddf4d8550b63d36e4e2d483f6cb (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho caracterizaram-se amostras de solo e substâncias húmicas (SH) extraídas de diferentes solos da Bacia do Médio Rio Negro e também determinaram-se a capacidade de complexação de íons Hg(II) por SH e constantes de troca entre espécies metálicas originalmente complexadas às SH por íons Hg(II). As amostras de solos foram caracterizadas através do teor de matéria orgânica, análises elementar e granulométrica. Os resultados mostraram que os teores de matéria orgânica para as amostras de solo diminuíram com a profundidade. Com base nos resultados de análise granulométrica feita nas amostras de solos, caracterizou-se o aumento dos teores de argila em função da profundidade com a conseqüente diminuição dos teores de areia e silte. As substâncias húmicas extraídas de amostras de solos coletados na Bacia do Médio Rio Negro-AM foram caracterizados por análise elementar, ressonância paramagnética eletrônica e ressonância magnética nuclear. Os resultados mostraram que, em função da profundidade, os valores das razões atômicas C/N foram praticamente constantes ao contrário das razões C/O e C/H, as quais diminuíram. As concentrações de radicais livres do tipo semi-quinona das substâncias húmicas variaram de 0,08 a 5,38 x 1018 spins g-1 de carbono, indicando diferença entre os níveis de humificação das SH extraídas de solos amazônicos. As SH extraídas de solos de regiões alagáveis apresentaram maiores concentrações de spins em relação às SH extraídas de regiões não alagáveis, indicando influência da umidade no processo de humificação. / In this research were characterized humic substances (HS) and soil samples extracted from Rio Negro-AM Medium Basin and capacity of complexation (CC) of Hg(II) by HS and constants of exchange between metallic species originally complexed in the HS by Hg(II) had also been determined. The soil samples were characterized through organic material composition, elemental and granulometry analysis. The results showed decreasing of the organic material composition with the depth. According to the results taken, was characterized an increasing in the composition of clay with the depth, but in the other hand, a reduction in silt and sand composition. The humic substances extracted of soil samples from Rio Negro-AM Medium Basin were characterized by elemental analysis, electronic paramagnetic resonance and nuclear magnetic resonance. The results had shown that, in function of the depth, the atomic ratio values C/N were constants, while the atomic ratio C/O and C/H decresed. The concentrations of free radicals of the humic substances were 0.08 to 5.38 x 1018 spins g-1 of carbon, indicating difference in the humification levels of HS extracted from Amazonian soils. The HS extracted in flooded regions showed bigger spins concentrations comparing to ones extracted in unflooded regions, showing that the humidity influences in the process of humification. The NMR of 13C dates showed the sequence of percentage of kind of carbon: aliphatic > ethers/hydroxyls > carboxyls/esthers/amides > aromatics > phenols @ carbonyls of aldehydes and ketones for HS samples extracted of the differences profiles of the Amazonian soils studied.
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Adubos verde na quantidade e qualidade da matéria orgânica do solo de cafezais em sistema de cultivo orgânico / Green manure in the quantity and quality of soil organic matter in the organic coffe systems cultivationCoelho, Marino Salgarello 16 July 2009 (has links)
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Previous issue date: 2009-07-16 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The use of leguminous as green manure is a widespread practice among family farms of Zona da Mata of Minas Gerais, contributing to the maintenance of the organic systems. With the addition of organic materials in the soil, the humic substances (HS) formation is a important process that increase the cycling time and contribute for soil C and N stocks maintenance. Beyond of the stocks, the constant addition of vegetal waste provides larger biological activity, increase of loads capable to minimize the loss of nutrients of the soil, it increases the aggregation and it reduces the erosion. The leguminous present different characteristics amongst themselves as the biomass production accumulate of nutrients and chemical characteristics. Those ones influence in the formation of the HS in the soil. Those characteristics can also be influenced by the climate of the place and, consequently, influencing in the formation and stabilization of the HS of the soil. The objective of this stud was quantity the C and N contents and the stocks of soil and on HS and evaluate the impact of the leguminous use as green manure in the quality of the HS under cultivation of organic coffee in two different edaphic conditions. Four leguminous species were cultivated between the coffee lines: Arachis pintoi, Calopogonium mucunoides, Stylozanthes guyanensis, Stizolobium aterrimum and spontaneous species, with prevalence of the Brachiaria plantaginea, during 4 years in family farmers of Araponga-MG (northwest exposure) and Pedra Dourada-MG (south exposure) in the area of the Zona da Mata of Minas Gerais. After 4 years of manure, was collected the soil in two depths (0-5 and 5-20 cm) and analyzed the content of Total Organic Carbon (TOC) and Total Nitrogen (TN) in the soil and on HS. In the farms were collected soil samples in volumetric rings to calculate the soil density. For the qualitative evaluation of the HS, they were extracted and purified for obtaining of the fulvic acids (FA) and humic acids (HA). FA and HA were accomplished elementary analysis (CHNO), UV-visible spectroscopy, Infra Red spectroscopy and termogravimetric of the purified material. The manure with leguminous and spontaneous species used as green manure can maintain the content of TOC, TN and the content of C and N on SH in the soil, maintaining the close values to the native forest. In the handling after 4 years of cultivation, just the humic fraction more labile (fulvic acids fraction - FAF) had effect in the treatments, what wasn t observed in the content of the most recalcitrant fractions (humic acids fraction HAF and humin fraction - HF). The content of C and N in HF were more the other fractions. The edaphic conditions promoted effect in the formation and in the stock of C and total N and of HS, and in the farm under conditions of smaller sunstroke (Pedra Dourada), the soil presented larger stocks of C and N. The effect of the position in the landscape (face exposure) it was superior to the effect of the clay content. The analyses to evaluate the quality, was verified that HA possesses larger weight molecular, larger hidrofobicity and larger condensation, for the presence of larger proportion of aromatic compositions and with larger content of C, checking larger structural stability in relation to FA. The farm under larger light incidence and temperature and smaller humidity, due to face of exposure northwest solar presented in FA, larger relationship O/C, relationship E4/E6, relationship 3300/1700 and value of inferior ITG, favoring the formation of FA with larger mass molar in relation to the found in the farm under smaller light incidence and temperature and larger humidity. In HA, the treatments obtained little effect due to the time of handling of the leguminous that they were for only 4 years. Among the leguminous, in FA, the treatment with Calopogonium mucunoides presented low content of C and high content of O in his composition, corroborating for the mass loss the temperature lowers, characterizing a material of easy mineralization. Already the treatment with Stylozanthes guyanensis provided FA with smaller molecular weight. / O uso de leguminosas como adubo verde é uma prática difundida entre os agricultores familiares da Zona da Mata Mineira, contribuindo para a manutenção dos sistemas orgânicos. Com a adição de matériais orgânicos ao solo, a formação das substancias húmicas é um importante processo, que aumenta o tempo de ciclagem e contribui para a manutenção dos estoques de C e N no solo. Além dos estoques, o aporte constante de resíduos vegetais proporciona maior atividade biológica, aumento de cargas capazes de minimizar a perda de nutrientes do solo, aumenta a agregação e diminui a erosão. As leguminosas apresentam características diferentes entre si como a produção de biomassa, acumulo de nutrientes e características químicas, características essas que influenciam na formação das substancias húmicas no solo. Essas características também podem ser influenciadas pelo clima do local e, consequentemente, influenciando na formação e estabilização das substancia húmicas do solo. Objetivou-se quantificar os teores e estoques de C e N no solo e nas substâncias húmicas e avaliar o impacto do uso de leguminosas como adubo verde na qualidade das substâncias húmicas em solos sob cultivo de café orgânico em duas condições edafoclimáticas distintas. Foram cultivadas nas entrelinhas do café quatro espécies de leguminosas: amendoim forrageiro (Arachis pintoi), calopogônio (Calopogonium mucunoides), estilosantes (Stylozanthes guyanensis), mucuna preta (Stizolobium aterrimum) e espécies espontâneas, com predomínio do capim marmelada (Brachiaria plantaginea), durante 4 anos em propriedades de agricultores familiares de Araponga - MG (face de exposição noroeste) e Pedra Dourada - MG (face de exposição sul) de agricultores familiares na região da Zona da Mata de Minas Gerais. Após 4 anos de manejo, foi realizada a coleta de solo em duas profundidades (0-5 e 5-20 cm) e analisado os teores de C e N total no solo e nas substancias húmicas. Por meio de amostras coletadas em anéis volumétricos para a obtenção da densidade do solo. Para a avaliação qualitativa das substâncias húmicas, foram extraídas e purificadas para obtenção dos ácidos fúlvicos (AF) e húmicos (AH). Foram realizadas análise elementar (CHNO), UV-Visível, Infra Vermelho e Termogravimetria do material purificado. O manejo com leguminosas e espécies espontâneas utilizadas como adubo verde pode manter os teores de COT, NT e os teores de C e N das SHs no solo, mantendo os valores próximos à mata nativa. No manejo após 4 anos de cultivo, apenas a fração húmica mais lábil (Fração ácidos Fúlvicos - FAF) teve efeito nos tratamentos, o que não foi observado nos teores das frações mais recalcitrantes (Fração Ácidos Húmicos - FAH e Fração Humina - FH). Os teores de C e N na FH foram superiores as outras frações. O efeito do uso da adubação verde foi verificado principalmente na superfície, com o aumento dos teores de C e N no solo. As condições edafoclimáticas promoveram efeito na formação e no estoque de C e N totais e das SHs, sendo que na propriedade sob condições de menor insolação (Pedra dourada), o solo apresentou maiores estoques de C e N. Foi verificado que os AH possuem maior peso molecular, maior hidrofobicidade e maior condensação, pela presença de maior proporção de compostos aromáticos e com maior teor de C, conferindo maior estabilidade estrutural em relação aos AF. A propriedade rural sob maior incidência de luz e temperatura e menor umidade, devido a face de exposição solar noroeste apresentou no AF, maior relação O/C, relação E4/E6, relação 3300/1700 e valor de ITG inferior, favorecendo a formação de AF com maior massa molar em relação ao encontrado na propriedade sob menor incidência de luz e temperatura e maior umidade. Nos AH, os tratamentos obtiveram pouco efeito devido ao tempo de manejo das leguminosas que foram por apenas 4 anos. Dentre as leguminosas, nos AF, o tratamento com calopogônio apresentou baixo teor de C e elevado teor de O em sua composição, corroborando para a perda de massa a temperatura baixa, caracterizando um material de fácil mineralização. Já o tratamento com estilosantes proporcionou AF com menor peso molecular.
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Substâncias húmicas como aditivos para o controle da volatilização de amônia proveniente da ureia / Humic Substances as additives to the control of the volatilization of originating from ammonia the ureaGuimarães, Gelton Geraldo Fernandes 26 July 2011 (has links)
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Previous issue date: 2011-07-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The lower NH3 volatilization from urea combined with humicified organic material has been attributed to the formation and adsorption of NH4+ due the high potential acidity and CEC. In this context, an experiment was conducted to evaluate NH3 volatilization from grainy urea or coated with humic acids (HA) and humic substances (HS) synthesized from vegetable charcoal (VC). The synthesis of HA and HS was due to the oxidation from charcoal of eucalyptus with HNO3 4.4 mol L-1 boiled under reflux for 4 hours. The HS were obtained directly by filtration. For the HA and HS achievement, It was solubilized in NaOH 0.5 mol L-1 and the fraction of HA was the one that precipitated until acidification to pH 2.0. It was produced grainy urea and urea coated with 5, 10, 15 and 20 % HA or HS. For the granulation, mixtures of urea (p.a.) and HA or HS were fused in 137 ° C and dripped using a pipette on a metal plate. With the fast cooling of the drops, granules in the form of tablets (4 to 5 mm in diameter) were formed. The commercial grainy urea (1-2 mm) was coated with HA or humic substances, using vegetable oil to promote adhesion. Volatilization of NH3 was evaluated in the laboratory in a closed system with continuous air flow, where 100 mg of N-urea was applied to a 100 cm3 surface of a red-yellow Acrisol (<2 mm). The synthesis income was 327 g kg-1 of HA and 784 g kg-1 of humic substance. The acidity of the carboxylic and phenolic groups was estimated through adjusting multiparameter non-linear potentiometric titration curve and, together, corresponded to the CEC of the HA (4750 mmol c kg-1) and HS (4360 mmol c kg-1), which were 9.5 and 8.7 times higher than the VC. The carboxylic groups were predominant either in the VC as in HA and HS, but the HA had a higher content of carboxylic groups and lower content of phenolic groups than the HS. The presence of carboxylic groups was confirmed by the spectra in the infrared range, showing absorption of stretching and deformation, characteristic of C = O bond with 1703.74 and 1706.88 cm-1 waves to the HA and HS, respectively. The urea fusion did not change the N content, but they ranged on average from 36 to 42 % with the addition of 20 to 5 % HA or HS. The highest volatilization rate occurred between 37 and 41 h after application and this time was little influenced by the proportions of HA and HS. Without the addition of HA and HS, the urea in a tablet shape and the commercial grainy urea provided a total volatilization of 517.4 and 468.8 mg g-1 of N-NH3. The largest reductions in evaporation occur with grainy urea (44.5 %) and coated (28.7 %) with 15 and 20 % HA, respectively. In the grainy urea the proportions of HA and HS provided equivalent reduction in evaporation. / A menor volatilização de NH3 a partir da ureia combinada com material orgânico
humificado tem sido atribuída à formação e à adsorção do NH4 + em razão da elevada acidez potencial e CTC. Neste contexto, foi conduzido um experimento para avaliar a volatilização de NH3 a partir da ureia granulada ou revestida com ácidos húmicos (AH) e substâncias húmicas (SH) sintetizadas de carvão vegetal (CV). A síntese dos AH e SH se deu pela oxidação do CV de eucalipto com HNO3 4,4 mol L-1 em ebulição sob refluxo por 4h. As SH foram obtidas diretamente por filtragem. Para obter os AH as SH foram solubilizadas em NaOH 0,5 mol L-1 e a fração AH foi aquela precipitada com a acidificação até pH 2,0. Foi produzida ureia granulada e ureia revestida com 5, 10, 15 e 20 % de AH ou SH. Para a granulação as misturas de ureia (p.a.) com AH ou SH foram fundidas a 137 °C e gotejadas com uma pipeta em uma placa metálica. Com o resfriamento rápido das gotas formaram-se grânulos na forma de pastilhas (4 a 5 mm de diâmetro). A ureia granulada comercial (1 a 2 mm) foi revestida com AH ou SH utilizando-se óleo vegetal para favorecer a aderência. A volatilização de NH3 foi avaliada em laboratório em um sistema fechado com fluxo contínuo de ar, onde 100 mg de N-ureia foi aplicada nas superfície de 100 cm3 de um Argissolo Vermelho-
Amarelo (< 2 mm). O rendimento na síntese foi de 327 g kg-1 de AH e 784 g kg-1 de SH. A acidez dos grupos carboxílicos e fenólicos foi estimada por meio do ajuste multiparamétrico não linear da curva de titulação potenciométrica e, em conjunto, corresponderam à CTC dos AH (4.750 mmolc kg-1) e SH (4.360 mmolc kg-1), que foram 9,5 e 8,7 vezes maiores do que a do CV. Os grupos carboxílicos predominaram tanto no CV como nos AH e SH, porém os AH apresentaram maior teor de grupos carboxílicos e menor teor de grupos fenólicos do que as SH. A ocorrência dos grupos carboxílicos foi confirmada pelos espectros na faixa do infravermelho que evidenciaram absorção de estiramento e deformação característica da ligação C=O com 1.703,74 e 1.706,88 cm-1 ondas para os AH e SH, respectivamente. A fusão da ureia não alterou o teor de N, mas estes variaram, em média, de 36 a 42 % com a adição de 20 a 5 % de AH ou SH. A maior taxa de volatilização ocorreu entre 37 e 41 h após a aplicação e este tempo foi pouco influenciado pelas proporções de AH e SH. Sem a adição de AH ou SH a ureia na forma de pastilha e a ureia granulada comercial proporcionaram volatilização total de 517,4 e 468,8 mg g-1 de N-NH3. As maiores reduções na volatilização ocorreram com a ureia granulada (44,5 %) e revestida (28,7 %) com 15 e 20 % de AH, respectivamente. Na ureia granulada as proporções de AH e de SH proporcionaram redução equivalente na volatilização.
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Interações entre íons Hg(II) e substâncias húmicas extraídas de diferentes solos da Bacia do Médio Rio Negro, Amazônia /Bellin, Iramaia Corrêa. January 2006 (has links)
Resumo: Neste trabalho caracterizaram-se amostras de solo e substâncias húmicas (SH) extraídas de diferentes solos da Bacia do Médio Rio Negro e também determinaram-se a capacidade de complexação de íons Hg(II) por SH e constantes de troca entre espécies metálicas originalmente complexadas às SH por íons Hg(II). As amostras de solos foram caracterizadas através do teor de matéria orgânica, análises elementar e granulométrica. Os resultados mostraram que os teores de matéria orgânica para as amostras de solo diminuíram com a profundidade. Com base nos resultados de análise granulométrica feita nas amostras de solos, caracterizou-se o aumento dos teores de argila em função da profundidade com a conseqüente diminuição dos teores de areia e silte. As substâncias húmicas extraídas de amostras de solos coletados na Bacia do Médio Rio Negro-AM foram caracterizados por análise elementar, ressonância paramagnética eletrônica e ressonância magnética nuclear. Os resultados mostraram que, em função da profundidade, os valores das razões atômicas C/N foram praticamente constantes ao contrário das razões C/O e C/H, as quais diminuíram. As concentrações de radicais livres do tipo semi-quinona das substâncias húmicas variaram de 0,08 a 5,38 x 1018 spins g-1 de carbono, indicando diferença entre os níveis de humificação das SH extraídas de solos amazônicos. As SH extraídas de solos de regiões alagáveis apresentaram maiores concentrações de spins em relação às SH extraídas de regiões não alagáveis, indicando influência da umidade no processo de humificação. / Abstract: In this research were characterized humic substances (HS) and soil samples extracted from Rio Negro-AM Medium Basin and capacity of complexation (CC) of Hg(II) by HS and constants of exchange between metallic species originally complexed in the HS by Hg(II) had also been determined. The soil samples were characterized through organic material composition, elemental and granulometry analysis. The results showed decreasing of the organic material composition with the depth. According to the results taken, was characterized an increasing in the composition of clay with the depth, but in the other hand, a reduction in silt and sand composition. The humic substances extracted of soil samples from Rio Negro-AM Medium Basin were characterized by elemental analysis, electronic paramagnetic resonance and nuclear magnetic resonance. The results had shown that, in function of the depth, the atomic ratio values C/N were constants, while the atomic ratio C/O and C/H decresed. The concentrations of free radicals of the humic substances were 0.08 to 5.38 x 1018 spins g-1 of carbon, indicating difference in the humification levels of HS extracted from Amazonian soils. The HS extracted in flooded regions showed bigger spins concentrations comparing to ones extracted in unflooded regions, showing that the humidity influences in the process of humification. The NMR of 13C dates showed the sequence of percentage of kind of carbon: aliphatic > ethers/hydroxyls > carboxyls/esthers/amides > aromatics > phenols @ carbonyls of aldehydes and ketones for HS samples extracted of the differences profiles of the Amazonian soils studied. / Orientador: André Henrique Rosa / Coorientador: Julio Cesar Rocha / Banca: Wilson Tadeu Lopes da Silva / Banca: Marisa Veiga Capela / Banca: Isabele Rodrigues Nascimento / Banca: Ézio Sargentini Junior / Doutor
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