Dissertations / Theses on the topic 'Soil biological activity'
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Franey-Gardiner, Mercedes. "The dynamics and biological activity of ALS-inhibiting herbicides in soil." Thesis, Cranfield University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426107.
Full textBerglund, Hanna. "Biological Soil Invertebrate Activity in a Tropical Rainforest : A comparison of soil invertebrate activity in two tropical rain forests in Borneo." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-411109.
Full textChoosai, Chutinan. "Biological activity in paddy fields : the role of soil engineers in ecosystem functioning." Paris 6, 2010. http://www.theses.fr/2010PA066156.
Full textPark, Kee Choon. "Enzymatic activity, microbial diversity, and weed seed banks in soils receiving different organic amendments and the biological fertilizer EM(tm) /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p3164535.
Full text(tm) after EM in title is for Trademark symbol. Typescript. Vita. Includes bibliographical references (leaves 120-142). Also available on the Internet.
Kurek, Danielle K. "Effects of prescribed burning on soil physical, biological, and chemical properties of the Oak Openings region of Northwest Ohio." Toledo, Ohio : University of Toledo, 2010. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=toledo1271430752.
Full textTypescript. "Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Masters of Science Degree in Biology." "A thesis entitled"--at head of title. Title from title page of PDF document. Bibliography: p. 58-63.
Oppong, Francis Kofi. "Studies on the biological activity of a novel herbicide (Triasulfuron) including studies of mobility and persistence in soil." Thesis, Bangor University, 1988. https://research.bangor.ac.uk/portal/en/theses/studies-of-the-biological-activity-of-a-novel-herbicide-triasulfuron-including-studies-of-mobility-and-persistence-in-soils(20ca442c-519c-4e3a-a11e-9e0b162ff25e).html.
Full textShi, Shengjing. "Influence of root exudates on soil microbial diversity and activity." Lincoln University, 2009. http://hdl.handle.net/10182/1549.
Full textUhrová, Anna. "Remediační potenciál huminových kyselin." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-234455.
Full textShort, Nicolyn. "Implications of green manure amendments on soil seed bank dynamics." University of Western Australia. School of Earth and Geographical Sciences, 2006. http://theses.library.uwa.edu.au/adt-WU2006.0022.
Full textFialho, Jamili Silva. "Indicadores da qualidade do solo em Sistemas AgrÃcolas anuais e perenes na Chapada do Apodi - CE." Universidade Federal do CearÃ, 2005. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=1739.
Full textEste trabalho se propÃs a avaliar as alteraÃÃes nas atividades microbiana, quÃmica e fÃsica em solo sob sistemas agrÃcolas anuais e perenes na regiÃo da Chapada do Apodi - CE. Procurou-se testar a hipÃtese de que o uso agrÃcola de Ãreas sob sistemas anuais e perenes causam alteraÃÃes ambientais que influenciam a biomassa e a atividade microbiana do solo, reduzindo-a em relaÃÃo a Ãreas sob vegetaÃÃo natural. Foram selecionadas duas Ãreas com respectivas testemunhas (vegetaÃÃo natural); a primeira sob cultivo de bananeiras (Fazenda Frutacor) e a outra sob cultivo de rotaÃÃo milho e soja (Fazenda Faedo). Coletaram-se amostras compostas de solo em trÃs profundidades (0-5, 5-15 e 15-25 cm) com quatro repetiÃÃes. Nas amostras coletadas foram realizadas anÃlises fÃsicas, quÃmicas e microbiolÃgicas. Fisicamente, observou-se uma elevaÃÃo no teor de argila, com o aumento da profundidade na Ãrea cultivada com banana e na mata natural pivot. Em relaÃÃo aos atributos quÃmicos do solo, os riscos potenciais de salinidade e de saturaÃÃo por sÃdio aparentemente sÃo desprezÃveis. As prÃticas de manejo reduziram o N e o carbono orgÃnico total nos solos das Ãreas sob cultivo. Quanto à microbiologia dos solos, o carbono da biomassa microbiana e a populaÃÃo de fungos micorrÃzicos arbusculares foram mais elevados na profundidade de 0-5cm do solo. A respiraÃÃo basal do solo mostrou que os solos das Ãreas avaliadas tÃm baixa atividade microbiana quando comparados a solos do Cerrado. A atividade e produÃÃo da arilsulfatase e da fosfatase Ãcida foram estimuladas possivelmente, pela competiÃÃo dos Ãnions H2PO4 - e SO4 - pelos mesmos sÃtios de adsorÃÃo nos colÃides do solo, nas Ãreas de banana e rotaÃÃo milho e soja. A maior atividade da enzima β-glucosidase ocorreu nas Ãreas cultivadas, influenciada pela quantidade e qualidade do resÃduo vegetal retornado ao solo.
This work had the proposed to evaluate the alterations in the microbial activities, chemistry and physics in soil under annual and perennial agricultural systems in the area of the Chapada do Apodi - CE. It tried to test the hypothesis that the agricultural use of areas under annual and perennial systems causes environmental alterations that they influence the biomass and the microbial activity of the soil, reducing it in relation to areas under natural vegetation. Two areas were selected with respective witness (natural vegetation); the first under cultivation of banana trees (Fazenda Frutacor) and the other under cultivation of rotation corn and soy (Fazenda Faedo). Samples composed of soil were collected in three depths (0-5, 5-15 and 15-25 cm) with four repetitions. In the collected samples physical analyses, chemistries and microbiological were accomplished. Physically, an elevation was observed in the clay text, with the increase of the depth in the area cultivated with banana and in the forest natural pivot. In relation to the chemical attributes of the soil, the potential risks of salinity and of saturation for sodium seemingly are worthless. The handling practices reduced N and the total organic carbon in the soils of the areas under cultivation. With relationship to the microbiology of the soils, the carbon of the microbial biomass and the population of arbuscular mycorrhizal fungi were more elevated in the depth of 0-5cm of the soil. The basal breathing of the soil identified that the soils of the appraised areas have microbial when compared low activity the soils of the Cerrado. The activity and production of the arylsulphatase and of the acid phosphatase were stimulated possibly, for the competition of the anions H2PO4- and SO4- for the same ranches of adsorption in the coloides of the soil, in the banana areas and rotation corn and soy. The largest activity of the enzyme β-glucosidase happened in the cultivated areas, influenced by the amount and quality of the vegetable residue come back to the soil.
Sellami, Fatima. "Fonctionnement biologique du sol sableux sous plantations d’eucalyptus d’âges différents. Effets du reboisement sur les communautés de la macrofaune et des microorganismes du sol en milieu tropical (Congo) et méditerranéen (Maroc)." Thesis, Paris Est, 2013. http://www.theses.fr/2013PEST0066.
Full textEucalyptus plantations in Congo (Pointe-Noire region) and in Morocco (Mamora forest) raised certain controversies regarding their effects on the sandy poor soils. In such anthropogenic ecosystems, researches on the subject have multiplied in order to ensure their sustainable management. However, knowledge on the biological functioning of soils in these plantations still needs to be explored. Main actors of this biological functioning are soil organisms and their activities which have been described very little, and need to be more studied. Our thesis encompasses this problematic. Therefore, we evaluated the impact of reforestation on the communities of macrofauna and microorganisms of soil, and the activity of different key enzymes, as well, related to main biogeochemical cycles (C, N and P). This research presents, particularly, a simultaneous consideration of two factors rarely mentioned before: the "age of the plantations" and "soil depth". We addressed these issues by a multi-scale study. We studied macroinvertebrates by their taxonomic diversity and vertically composition by a combined approach (TSPF + English square). Subsequently, the characterization of structure and diversity of microbial communities was done by density measurements, morphotype-specific (in-vitro culture) and the genetic determinations (DGGE) and by measuring the metabolic potential in terms of functional communities (Biolog plates). Finally, soil biological activity was evaluated by determining the activity of eight different enzymes and the total microbial activity (FDA hydrolysis).Therefore, as compared to the adjacent natural forest soils, this study allowed us to demonstrate that the introduction of eucalyptus plantations, in savanna (Congo) or in degraded cork oak ecosystem (Morocco), alters the structure and diversity of macrofauna communities, soil microorganisms and the enzymatic activity profiles. Consequently, the biological functioning of the soils is impacted both in terms of the age of plantations and soil depth. However, the proportions and the consequences of this impact were very specific in each case, with the exception of enzymatic activities related to the nitrogen cycle, which influenced comparatively in both studies. These activities decreased significantly along with the stand age of eucalyptus plantations, confirming the deficient status of nitrogen in such plantations
Peixoto, Fabiana Gomes Teixeira. "Biomassa microbiana e atividade enzimática em solos do Estado de São Paulo sob vegetação nativa e cultivados /." Jaboticabal : [s.n.], 2010. http://hdl.handle.net/11449/88281.
Full textAbstract: The removal of the natural vegetation and the use of the soil for agricultural purposes may cause deep alterations in the soil properties depending on the management applied. It is important periodic evaluations of soil properties in order to detect alterations that can degrade the soil. Among soil properties, soil biological activities are those that first indicate soil modifications. The objective of this study was to evaluate changes in soil biological attributes, comparing areas under native forests with areas with the same soils and cultivated with sugarcane or maize. From a georeferenced point, each selected area was divided into three plots with 100 m2 (10 x 10 m), and 20 simple samples were collected in the 0-0.20 m depth, which were mixed to form a composed sample. The studied areas included the eleven different Oxisols, Ultisols six, three Neossolos two Alfisols, an Ultisol, a Organosol a Cambisol and a Chernosol, these soils located in different districts all in São Paulo State. The following soil attributes were evaluated in the soil samples: carbon and nitrogen in the soil microbial biomass, basal respiration, metabolic quotient (qCO2), the activity of the enzymes amylases, arylsulphatase, cellulose, dehydrogenases, phosphatase acid, proteases and the hydrolysis of fluorescein diacetate (FDA). The activities of arylsulfatase and dehydrogenase were the ones that best reflected changes undergone by anthropogenic soils in the study. Organic matter associated and cation exchange capacity were the soil properties that best correlated with the biological and biochemical attributes evaluated.
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Inagaki, Thiago Massao. "CALAGEM E GESSAGEM COMO ESTRATÉGIAS PARA AUMENTO DO SEQUESTRO DE CARBONO EM PLANTIO DIRETO." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2016. http://tede2.uepg.br/jspui/handle/prefix/2279.
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Although recognized, the effects of lime and gypsum applications over soil organic matter dynamics is still scarcely studied. This research was developed based in the hypothesis the lime and gypsum applications create a favorable environment for biological activity, leading to increase of carbon sequestration and crop productivity. In this way, the objectives of this study were: a) to evaluate the impact of lime and gypsum applications in the soil biological quality, soil organic carbon (SOC) stocks and crop productivity in a long-term no-till system; and b) to evaluate through a laboratory incubation experiment the effects of lime and gypsum in the SOC stocks, Ca and Mg content and soil basal respiration. The field experiment was stablished in 1998 on clay Oxisol (Typic Hapludox), in Ponta Grossa – PR Brazil in a split-plot completely randomized block design. The main plots were comprised in three liming treatments: a) Control, with no lime applications, b) Incorporated lime (IL) at the rate of 4,5 Mg ha-1 and c) Surface-applied lime (SL) at the rate of 4.5 Mg ha-1 divided in three annual applications of 1,5 Mg ha-1 from the experiment establishment. The subplots were comprised by gypsum applied on soil surface at four rates: 0, 3, 6 and 9 Mg ha-1. The soil samples were collected in 2013, fifteen years after the experiment establishment. A laboratory incubation experiment was also carried out to evaluate the effects of both practices. We collected undisturbed samples in 5x5 cm steel rings, which were maintained under 28ºC in 50% of water maximum retention. The experiment design was completely randomized plots with 2x4 factorial design. The treatments assessed were: a) application or not of 4.5 Mg ha-1 of lime; and b) gypsum rates of 0, 3, 6, and 9 Mg ha-1. Over the ring surface, we added corn and soybean residues in order to simulate no-till conditions. In the field experiment, liming provided increase of soil biological activity, SOC stocks, crop productivity, biomass-C input and soil fertility. The C-biomass input and Ca content contributed significantly for increases in SOC stocks. The soil biological activity (measured by enzyme activities) was positively influenced mainly by the labile SOC fractions. Gypsum application positively contributed to increases in SOC labile fractions and arylsulfatase activity. In the incubation experiment, the lime application significantly increased the soil basal respiration, labile SOC stocks and Ca and Mg contents. The gypsum applications significantly increased the labile SOC stocks and Ca content. We observed significant contributions of soil basal respiration and Ca content in the SOC stocks increase. We conclude the lime and gypsum consist in important strategies to promote increases in SOC stocks, governed mainly by the role of Ca as a SOC biding agent and the C-biomass input; and that the use of undisturbed samples were an efficient strategy to assess the effects of lime and gypsum in no-till system.
Apesar de reconhecidos, os efeitos da calagem e gessagem sobre a dinâmica da matéria orgânica ainda são pouco estudados. Este trabalho foi desenvolvido baseando-se na hipótese de que as aplicações de calcário e gesso criam condições favoráveis para o aumento da atividade biológica do solo conduzindo a um incremento do sequestro de carbono e produtividade das culturas. Dessa forma, o objetivo desse trabalho foi: a) avaliar o impacto da calagem e gessagem na atividade biológica do solo, estoques de C e produtividade agronômica em uma área de plantio direto de 15 anos; e b) Avaliar através de um estudo de incubação em laboratório utilizando amostras indeformadas de solo simulando condições de plantio direto, os efeitos da adição de calcário e gesso no solo sobre os estoques de C, conteúdo de Ca e Mg e respiração basal do solo. O experimento a campo foi implantado em 1998 em um Latossolo vermelho argiloso em Ponta Grossa – PR. O delineamento experimental foi em blocos inteiros aleatorizados com parcela subdividida. Os tratamentos implementados nas parcelas foram: a) controle, sem calcário; b) calcário aplicado de forma incorporada (C-inc) na dose de 4,5 Mg ha-1; e c) calcário aplicado em superfície (C-sup) na dose de 4,5 Mg ha-1, dividido em três aplicações anuais de 1.5 Mg ha-1 a partir da instalação do experimento. Os tratamentos que compuseram as subparcelas foram quatro doses de gesso: 0, 3, 6 e 9 Mg ha-1. As amostras de solo foram coletadas em 2013, quinze anos após a implantação do experimento. Um experimento realizado em laboratório com amostras incubadas também foi realizado para estudar os efeitos das práticas. Foram coletadas amostras indeformadas em anéis cilíndricos 5 x 5 cm, mantidas a 28ºC a 50% da capacidade máxima de retenção de água. O delineamento experimental foi inteiramente aleatorizado com fatorial 2 x 4. Os tratamentos foram: a) aplicação ou não de 4,5 Mg ha-1 de calcário em superfície; e b) aplicações superficiais de gesso nas doses de 0, 3, 6 e 9 Mg ha-1. Na superfície do anel foi adicionado resíduos de palha de milho e de soja em períodos distintos para simular uma condição de plantio direto. No experimento a campo, a calagem proporcionou aumento da atividade biológica do solo, estoques de C, produtividade agronômica, aporte de C via resíduos culturais e fertilidade do solo. O aporte de C via resíduos culturais e o conteúdo de Ca+2 do solo contribuíram positivamente para o aumento dos estoques de C. A atividade biológica (medida através da atividade enzimática) foi positivamente influenciada principalmente pela atuação das frações mais lábeis do C. O gesso contribuiu positivamente para o aumento das frações mais lábeis do C e também para a atividade de arilsufatase. No experimento de incubação, a aplicação de calcário aumentou significativamente a respiração basal do solo, estoques de C e concentrações de Ca e Mg. A gessagem aumentou significativamente as frações mais lábeis do C e o conteúdo de Ca. Foram observadas influências significativas do conteúdo de Ca e da respiração basal no aumento dos estoques de C do solo. Conclui-se que a calagem e a gessagem consistem em importantes estratégias para proporcionar aumento dos estoques de C do solo governado principalmente pela atuação do Ca como ligante da matéria orgânica e pelo aporte de C via resíduos culturais e que a utilização de amostras indeformadas com aporte de resíduos em superfície consiste em uma eficiente estratégia para avaliar o efeito da aplicação de calcário e gesso em plantio direto.
Peixoto, Fabiana Gomes Teixeira [UNESP]. "Biomassa microbiana e atividade enzimática em solos do Estado de São Paulo sob vegetação nativa e cultivados." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/88281.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A derrubada da vegetação nativa e o uso do solo para atividades agropecuárias podem causar alterações nos atributos do solo que variam de intensidade, em função do tipo de manejo adotado. É importante o acompanhamento na variação dos atributos do solo no sentido de detectar alterações que venham em detrimento do potencial produtivo, as propriedades biológicas são as que primeiro se alteram, sendo de grande validade na detecção de impactos negativos no solo pelo uso. O objetivo deste estudo foi verificar alterações em atributos biológicos, comparando áreas sob vegetação nativa com áreas cultivadas com cana-de-açúcar, milho, pastagem e citros. A partir de um ponto georreferenciado, cada área amostrada foi dividida em três sub áreas com 100 m2 (10 x 10 m), sendo coletadas 20 amostras simples em cada uma delas na profundidade 0-0,20 m, que foram misturadas para formar uma amostra composta. As áreas em estudo incluíram onze Latossolos, seis Argissolos, três Neossolos, dois Nitossolos, um Gleissolo, um Organossolo, um Cambissolo e um Chernossolo, solos estes situados em diferentes municípios do Estado de São Paulo. Nas amostras de solo foram avaliados: carbono e nitrogênio da biomassa microbiana, respiração basal, quociente metabólico (qCO2) e atividade das enzimas amilase, arilsulfatase, celulase, desidrogenase, fosfatase ácida, protease e o potencial de hidrólise do diacetato de fluoresceína (FDA). As atividades de arilsulfatases e desidrogenases foram as que melhor refletiram alterações antrópicas sofridas pelos solos em estudo. A matéria orgânica e a capacidade de troca catiônica foram às propriedades químicas do solo que melhor se correlacionaram com os atributos biológicos e bioquímicos avaliados.
The removal of the natural vegetation and the use of the soil for agricultural purposes may cause deep alterations in the soil properties depending on the management applied. It is important periodic evaluations of soil properties in order to detect alterations that can degrade the soil. Among soil properties, soil biological activities are those that first indicate soil modifications. The objective of this study was to evaluate changes in soil biological attributes, comparing areas under native forests with areas with the same soils and cultivated with sugarcane or maize. From a georeferenced point, each selected area was divided into three plots with 100 m2 (10 x 10 m), and 20 simple samples were collected in the 0-0.20 m depth, which were mixed to form a composed sample. The studied areas included the eleven different Oxisols, Ultisols six, three Neossolos two Alfisols, an Ultisol, a Organosol a Cambisol and a Chernosol, these soils located in different districts all in São Paulo State. The following soil attributes were evaluated in the soil samples: carbon and nitrogen in the soil microbial biomass, basal respiration, metabolic quotient (qCO2), the activity of the enzymes amylases, arylsulphatase, cellulose, dehydrogenases, phosphatase acid, proteases and the hydrolysis of fluorescein diacetate (FDA). The activities of arylsulfatase and dehydrogenase were the ones that best reflected changes undergone by anthropogenic soils in the study. Organic matter associated and cation exchange capacity were the soil properties that best correlated with the biological and biochemical attributes evaluated.
PRAGANA, Rossanna Barbosa. "Caracterização pedológica e diagnóstico da qualidade de solos sob plantio direto na Serra do Quilombo, sudoeste piauiense." Universidade Federal Rural de Pernambuco, 2011. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/5381.
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This research was conducted in the Cerrado of Piauí. This area has been targeted for exploitation without due concern for the preservation of natural resources, where production systems are characterized by intensive use of land. The objective of this research was to deepen knowledge about the Serra do Quilombo pedoenvironment Bom Jesus, PI, and evaluate the effect of notillage on altering the characteristics of soils cultivated with soybean. The research was conducted in two parts. The first part consists of the recognition of the soils of the Sierra. The examination of soils, identification and sampling were carried out by trenching. The samples were analyzed for morphological, physical, chemical and mineralogical composition. The analysis of the context in which the sequence of profiles is inserted, and the attributes of the analyzed soils converge to a single class of soil, the Oxisols, however, are apparently formed from parent materials with different contributions, which can be confirmed by the textural variation along the transect and the behavior of oxides. The second part was to assess changes in soil properties, due to the different times of implantation of the no-tillage system, in relation to native Cerrado. The results were submitted to variance analysis and additional analysis was used as multivariate techniques. The second part of the research consisted of two studies. The first was the effect of no-tillage on morphological attributes Yellow Latosol (Oxisol), by evaluating the color, structure and consistency, and the effect on soil physical properties: particle-size-distribution, clay dispersion, degree of clay flocculation, silt / clay comparison, bulk density and particle, total porosity, macroporosity, microporosity, aggregate stability and soil resistance to penetration. The type of management imposed on the ground, conventional till and subsequent implantation of no-tillage system, contributed to alter the morphological properties of soil such as structure and consistency, applied to horizon A. No-tillage also affected soil physical properties in relation to native Cerrado, especially in the surface layer. The second study assessed the effect of no-tillage on the chemical and biological dynamics of organic matter in the same Oxisols. We evaluated the following attributes: exchangeable cations, sum of bases, CEC, base saturation, pH, organic carbon, aluminum saturation, total nitrogen and phosphorus as chemical attributes. We also evaluated organic soil basal respiration, microbial biomass, metabolic quotient and microbial quotient, and for the dynamics of organic matter we used physical and chemical fractionation. The management of the ground solo with conventional cultivation and subsequent implantation of notillage system also altered the chemical and biological soil compared with native Cerrado. As for the physical fractionation of organic matter, some fractions showed significant effect, deferring the soil of the native Cerrado of cultivated soils under no-tillage system, however for the chemical fractions of organic matter there was no significant effect.
Esta pesquisa foi realizada no Cerrado piauiense. Esta área vem sendo alvo de exploração sem a devida preocupação com a manutenção dos recursos naturais, onde os sistemas de produção têm se caracterizado pelo uso intensivo do solo. O objetivo geral desta pesquisa foi aprofundar o conhecimento sobre os pedoambientes da Serra do Quilombo em Bom Jesus- PI e avaliar o efeito do plantio direto na alteração das características de solos cultivados com soja. A pesquisa foi desenvolvida em duas partes. A primeira parte constou do reconhecimento dos solos da serra. O exame dos solos, a identificação e a coleta de amostras foram realizados mediante abertura de trincheiras. As amostras foram submetidas às análises para caracterização morfológica, física, química e mineralógica. A análise do contexto em que a sequência dos perfis está inserida, e os atributos dos solos analisados convergem para uma única classe de solo, a dos Latossolos, entretanto, são aparentemente formados de materiais de origem com diferentes contribuições, o que pode ser comprovado pela variação textural ao longo do transecto e do comportamento dos óxidos. A segunda parte foi verificar as alterações nos atributos do solo, em decorrência dos diferentes tempos de implantação do sistema plantio direto, em relação ao Cerrado nativo. Os resultados foram submetidos à análise de variância e como análise complementar, técnicas multivariadas foram utilizadas. A segunda parte da pesquisa consistiu em dois estudos. O primeiro avaliou o efeito do plantio direto sobre os atributos morfológicos dos Latossolos Amarelos, através da avaliação da cor, da estrutura e da consistência; e o efeito do planto direto sobre os atributos físicos através da distribuição das frações granulométricas, argila dispersa em água, grau de floculação, relação silte/argila, densidade do solo e das partículas, porosidade total, macroporosidade, microporosidade, estabilidade de agregados e resistência do solo à penetração. Os resultados indicaram que o manejo imposto ao solo com cultivo convencional e posterior implantação do sistema plantio direto contribuiu para alterar as propriedades morfológicas do solo como a estrutura e a consistência, que sofreram transformações no horizonte A. O plantio direto também afetou os atributos físicos do solo em relação ao Cerrado nativo, notadamente no horizonte superficial. O segundo estudo avaliou o efeito do plantio direto sobre atributos químicos e biológicos e na dinâmica da matéria orgânica dos mesmos Latossolos Amarelos. Foram avaliados os seguintes atributos: complexo sortivo, soma de bases, CTC, saturação por bases, pH, carbono orgânico, saturação por alumínio, nitrogênio total e fósforo disponível, como atributos químicos. Como atributos biológicos foram avaliados a respiração basal do solo, carbono da biomassa microbiana, quociente metabólico e quociente microbiano. E para avaliar a dinâmica da matéria orgânica foi feito o fracionamento físico e químico. Os resultados indicaram que o manejo imposto ao solo com cultivo convencional e posterior implantação do sistema plantio direto também contribuiu para alterar as propriedades químicas e biológicas do solo em comparação com o Cerrado nativo. Quanto ao fracionamento físico da matéria orgânica, algumas frações apresentaram efeito significativo diferindo o solo do Cerrado nativo dos solos cultivados com o sistema plantio direto; no entanto, para as frações químicas da matéria orgânica não houve efeito significativo.
Silva, Danni Maisa da. "Biota do solo em pastagem sob aplicação sucessiva de dejetos de suínos." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/3364.
Full textO uso sucessivo de dejetos de suínos como fertilizante do solo em áreas de pastagem é uma prática comum na região sul do Brasil. Embora existam benefícios econômicos da reutilização dos dejetos, esta prática apresenta sérios riscos ambientais e pode causar alterações na composição e na atividade dos organismos do solo. Os organismos edáficos e os indicadores microbiológicos de qualidade do solo são bastante sensíveis e permitem o monitoramento das condições do ambiente edáfico. Este trabalho teve por objetivo estudar o efeito da aplicação sucessiva de dejetos de suínos em áreas de pastagem sobre a composição, atividade biológica e a qualidade microbiológica do solo. O estudo foi realizado em Três Passos/RS, em duas épocas de coleta (inverno e primavera), em áreas com uso de dejetos suínos há 2 anos (A2), há 14 anos (A14) e mata nativa (MN). Em todas as áreas foram analisadas a composição dos organismos do solo através do uso do PROVID e do TSBF, a atividade biológica, com o uso de litter bags e do ensaio lâmina bait e a qualidade microbiológica do solo a partir da determinação do teor de C na biomassa microbiana, respiração microbiana do solo, quociente metabólico (qCO2) e atividade das enzimas β Glicosidase, urease e Hidrólise do Diacetato de Fluoresceína (FDA). O uso sucessivo de dejetos de suínos no solo alterou as características biológicas, de acordo com o tempo de aplicação do mesmo; influencia a composição e a diversidade da fauna edáfica, aumentando o número total de indivíduos, principalmente de colêmbolos; a atividade da biota do solo é influenciada pela época de coleta das análises e pela profundidade, sendo maior especialmente até os 6 cm do solo; o uso sucessivo de dejetos de suínos em pastagem não influencia o carbono da biomassa, a respiração microbiana e o quociente metabólico do solo permitindo a manutenção dos níveis de qualidade microbiológica do solo em relação à mata nativa; a atividade enzimática do solo foi influenciada pelo uso de dejetos de suínos, sendo que a urease e a Hidrólise do Diacetato de Fluoresceína (FDA) foram sensíveis na detecção de diferenças na atividade dos microrganismos dos solos com uso de dejetos de suínos enquanto que a enzima β-Glicosidase não permitiu a diferenciação entre as áreas estudadas.
Laurent, Fabien. "Impact de l'oxydation chimique et de la refonctionnalisation sur des paramètres physico-chimiques et biologiques de terres contaminées au HAP." Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0033/document.
Full textIn order to clean up polycyclic aromatic hydrocarbon (PAH) contaminated soils, various techniques have been developed during the last decades, but their impact on soil functions was rarely considered. The objective of this study was to assess the impact of chemical oxidation treatments on different physico-chemical and biological parameters of PAH contaminated soil and to propose solutions to improve the biological functioning of oxidized soil. Various laboratory and field experiments have shown that the efficiency of chemical oxidation reactions (Fenton reaction and activated persulfate) on PAH concentrations depended on pollutant availability and soil physico-chemical properties. Besides, intense acidification processes have been observed on uncarbonated soil with a strong impact on soil physico-chemical and biological parameters. Moreover, this alteration was higher with activated persulfate treatment, leading to the loss of trace metals in water percolation. In the strongly acidified soil, the input of materials, suitable for pH increase, resulted in the restoration of biological activities and soil capacity to support vegetation. The association of chemical oxidation treatment and restoration techniques could present a good mean for soil rehabilitation. Finally, an index, which aimed to represent soil conditions based on the weight given to different parameters, was proposed and was used to evaluate changes induced by oxidation treatments and restoration techniques
Jacometti, Marco Alexander Azon. "Enhancing ecosystem services in vineyards to improve the management of Botrytis cinerea." Phd thesis, Lincoln University. Bio-Protection and Ecology Division, 2007. http://theses.lincoln.ac.nz/public/adt-NZLIU20070126.115223/.
Full textRizvi, Syed. "Amendements calco-magnésiens de bassins versants forestiers acidifiés : effets sur la dynamique de la matière organique et l'activité biologique du sol." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4796.
Full textThe main objective of this work is to assess the consequences of calco-magnesium liming on two acidified forested catchments in Vosges Mountain (sandstone and granite) on humus morphology, abundance and diversity of mesofauna, fungal biomass and carbon storage in organic horizons 5 and 7 years after liming. Moreover, we performed a study to verify under laboratories conditions by using microcosms filled with soil from acidified catchments lying on sandstone and granite in order to study the short-term effect of calco-magnesium liming. During the two field campaigns, we determined calcium and magnesium contents of OL horizon, pH, humus morphology, mesofauna abundance and diversity, fungal biomass, soil carbon storage of organic layers OL, OF and OH.Results indicated that calco-magnesium liming affects studied parameters in different ways according to elapsed time after liming and the geological substrate (sandstone and granite), the more acidic catchment (sandstone) showing the most remarkable reaction. Results of immediate effects of liming showed a decrease of mesofauna abundance and then gradually increasing tendencies in field campaigns after 5 years while no effect after 7 years after liming. The opposite or no effects were observed on granite substrate. Ca and Mg contents in OL horizon increased by liming but this effect were only significant on sandstone substrate. Soil fungal biomass was not affected by liming but was significantly higher on granite substrate than sandstone. Liming increased the OH horizon thickness on sandstone while decreased the OL horizon on granite, under the influence of biological activity (mesofauna vs microorganisms)
Owen, Andrew. "Phosphorus redistribution in acid archaeological soils from North Wales." Thesis, Bangor University, 1999. https://research.bangor.ac.uk/portal/en/theses/phosphorus-redistribution-in-acid-archaeological-soils-from-north-wales(368d2ef4-5334-461b-8795-4e66a616b62f).html.
Full textGrigaliūnienė, Kristina. "Ilgalaikio tręšimo poveikis skirtingos kilmės dirvožemių biologiniam aktyvumui." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2006. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20060117_170123-78293.
Full textDufrénoy, Pierrick. "Valorisation en synthèse organique d'éco-catalyseurs hétérogènes régénérables à partir de matériaux verts cultivés sur des sols contaminés." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMLH30/document.
Full textThe activities of the former metallurgy industries specialized in the production and processing of lead, zinc or other metals have resulted in significant metallic pollution of soils depending on their location. Current studies propose solutions for the requalification of these soils through the phytoremediation processes in order to maximize the value of plants grown on these contaminated soils. This PhD thesis project was thus realized with the aim of valorizing regenerative heterogeneous ecocatalysts. The latter were obtained from the plants cultivated on contaminated soils in organic synthesis for the production of high value added molecules. The contaminated soils used in this project came from the Hauts-de-France region (Auby and Noyelles-Godault). In this light, four types of reactions have been tested to validate the efficiency and recyclability of ecocatalysts: The aminolysis reaction The Friedel-Crafts reaction The aza-Michael transformation The transesterification reactionThe zinc-rich ecocatalysts (EcoZn), obtained from the plant biomass of ryegrass (Lolium perenne L.), were characterized by physicochemical methods and validated their efficiency and recyclability criteria. The latter were successfully used to reach various series of compounds with anti-inflammatory activity known (piroxicam, meloxicam, idrocilamide) and new, inhibitors of farnesyltransferase (for anticancer purpose or to fight orphan diseases such as progeria) or to discover a new aza-Michael acceptor
Jezile, G., D. Westfall, G. Peterson, DR Child, DP Turner, and Averbeke W. Van. "Effects of liming on microbial activity and N mineralization in broiler manure-amended soils from Bizana, Eastern Cape, South Africa." Taylor & Francis, 2008. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001059.
Full textCaetano, Ana Luísa Neto. "Derivation of soil screening values for metals in Portuguese natural soil." Doctoral thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13764.
Full textThe increasing human activity has been responsible by profound changes and a constinuos degradation of the soil compartment in all the European territory. Some European policies are appearing focusing soil’s protection and the management of contaminated sites, in order to recover land for other uses. To regulate the risk assessment and the management of contaminated soils, many European member states adopted soil guideline values, as for example soil screnning values (SSV).These values are particularly useful for the the first tier of the Ecological Risk Assessment (ERA) processes of contaminated sites,especially for a first screening of sites requiring a more site-specific evaluation. Hence, the approriate definition of regional SSVs will have relevant economic impacts in the management of contaminated sites. Portugal is one of European Member States that still lack these soil guideline values. In this context, this study gaves a remarkable contribution in the generation of ecotoxicological data for soil microbiological parameters, terrestrial plants and invertebrates for the derivation of SSVs for uranium (U), cadmium (Cd) and copper (Cu), using a Portuguese natural soil, representative of a dominant type of soil in the Portuguese territory. SSVs were derived based on two methods proposed by the the Technical Guidance Document for Risk Assessment of the European Commission; namely the assessment factor method (AF) and the species sensitivity distribution (SSD) method (with some adaptations). The outputs of both methods were compared and discussed. Further, this study laid the foundation for a deeper reflection about the cut-off (hazard concentration for a given percentage of species - HCps) to be estimated from the SSDs, and to be selected for the derivation of SSVs, with the adequate level of protection. It was proven that this selection may vary for different contaminants, however a clear justification should be given, in each case. The SSvs proposed in this study were for: U (151.4 mg U kg-1dw), Cd (5.6 mg Cd kg-1dw), and Cu (58.5 mg Cu kg-1dw) These values should now be tested for their descriminating power of soils with different levels of contamination. However, this studies clarifies the approach that should be followed for the derivation of SSVs for other metals and organic contaminants, and for other dominant types of Portuguese natural soils.
O aumento das atividades humanas tem sido responsável por mudanças profundas e por uma degradação contínua do compartimento solo, em todo o território Europeu. Em resposta a este problema, algumas políticas Europeias estão agora a emergir orientadas especificamente para a proteção do solo e para a gestão das áreas contaminadas, a fim de recuperar os solos degradados para outros usos. Para regulamentar a avaliação de risco e a gestão de solos contaminados, muitos Estados-Membros Europeus adoptaram valores de qualidade do solo, como por exemplo os “valores de rastreio ou triagem” (do inglês: soil screening values ou SSVs). Estes valores são particularmente úteis para a primeira etapa dos processos de avaliação de risco ecológico (ARE) de locais contaminados, especialmente para um primeiro rastreio dos locais, destinado a separar aqueles em que os riscos são claramente reduzidos daqueles que exigem uma avaliação mais específica e aprofundada para o local. Assim, a definição de SSVs regionais terá impactos económicos relevantes na gestão dos locais contaminados. Portugal é um dos Estados-Membros Europeus que ainda não definiu SSVs. Neste contexto, este estudo dá uma notável contribuição na geração de dados ecotoxicológicos para parâmetros microbiológicos do solo, plantas terrestres e invertebrados necessários para a obtenção de SSVs para urânio (U), cádmio (Cd) e cobre (Cu), utilizando um solo natural Português, representante de um tipo dominante de solo existente no território nacional. Assim, foram obtidos SSVs para os metais referidos com base em dois métodos propostos pelo Documento de Orientação Técnica para Avaliação de Riscos da Comissão Europeia, nomeadamente o método dos factores de avaliação (do inglês: assessment factors ou AF) e o método probabilístico da distribuição da sensibilidade espécies (do inglês: species sensitivity distributions ou SSDs) (com algumas adaptações). Os resultados dos dois métodos foram comparados e discutidos. Além disso, este estudo lançou as bases para uma reflexão mais profunda sobre o ponto de corte (concentração de risco para uma determinada percentagem de espécies) a ser estimado a partir das distribuições de sensibilidade das espécies (SSDs), e para ser selecionado para a obtenção de SSVs, com o nível adequado de proteção. Neste estudo foi comprovado que esta seleção pode variar para diferentes metais ou outros contaminantes, no entanto, uma justificação clara deve ser dada, em cada caso. Os SSvs propostos neste estudo foram de: U (151,4 mg U kg- 1ms ), Cd (5,6 mg Cd kg- 1ms ) e Cu ( 58,5 mg Cu kg- 1 ms) Estes valores devem agora ser testados quanto à sua capacidade para descriminar solos com diferentes níveis de contaminação. No entanto, este estudo esclarece e sugere a abordagem que deve ser seguida para a derivação de SSVs para outros metais e contaminantes orgânicos, e para outros tipos dominantes de solos naturais portugueses.
El, Alam Imad. "Phytoremédiation d'un sol contaminé de la Bekaa (Liban) : Valorisation de la biomasse par production d'huiles essentielles à activités biologiques." Thesis, Littoral, 2018. http://www.theses.fr/2018DUNK0486.
Full textLocated in the Bekaa valley in Lebanon, The Litani River is exposed to agricultural, industrial, domestic and urban wastewaters. Through the irrigation of agricultural soils, the river's water contributes to soil and culture contamination and represents a risk for human health and environment. Amongst the emergent sustainable remediation methods, there is arbuscular mycorrhizal fungi (AMF) assisted-phytoremediation. However, one of the limitation in using phytoremediation as depollution method is its socio-economic profitability. Among the eco-innovative valorization processes with high profitability, the cultivation of aromatic and medicinal plants producing essential oils (EO) with biological activities has been suggested as a promising option. Thus, this thesis work aims firstly at characterizing the soil of an experimental site located at Marj-Bekaa and directly irrigated by the Litani's water and secondly at proposing a mode of management of the contaminated soil based on the production of EO that can meet environmental, economic and social expectations. Our findings showed that the soil sampled in Marj-Bekaa is mainly contamined by metal trace elements [Ni (88 mg.Kgˉ ¹), Cr (122 mg.Kgˉ ¹), V (170 mg.Kgˉ ¹) and Mn (551 mg.Kgˉ ¹) and alkanes (2.5 g.Kgˉ ¹ of soil). This contamination is causing (i) cytotoxicity against both bronchial and hepatic human cells revealed by the evaluation of two enzyme activities, extracellular lactate dehydrogenase and mitochondrial dehydrogenase, as well as (2) ecotoxicity pointed out by the reduction of (i) seed germination (wheat, clover, alfalfa, ryegrass and tall fescue), (ii) soil microbial biomass [Gram-positive and Gram-negative bacteria, arbuscular mycorrhizal fungal (AMF), ectomycorrhizal and saprotrophic fungi], (iii) abundance and diversity of AMF spores as well as (iv) the plant diversity and richness. The AMF-assisted phytoremediation of the Bekaa experimental site was evaluated both in microcosms and in situ experiments using an aromatic plant producing EO, oregano (Origanum syriacum L.). Our results revealed that oregano plant possess an alkane's dissipation potential and no polluant transfer is detected in EO. Moreover, the mycorrhization modified the EO composition. On the over hand, our study evaluated several biological (antifungal, antioxidant and anti-inflammatory) activities of a range of EO extracted from many plant species including oregano, in the presence and the absence of cyclodextrines (HP-β-CD), cyclic oligosaccharides that encapsulate EO and enhance their bioavailabilities
Machado, Jéssica Cristine Viera. "RECUPERAÇÃO DE SOLO EM PROCESSO DE ARENIZAÇÃO COM O USO DE ESPÉCIES VEGETAIS EM POMAR DE AMOREIRA-PRETA." Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/4857.
Full textThe southwest region of Rio Grande do Sul (RS) state has widespread areas with sandy soils in the process of sandification. In the present study, we report the effect of different intercropping in blackberry plants on the soil recuperation and crop productivity. The experiment was conducted in São Francisco de Assis located in southwest region of the RS. The soil was a typical Psament with 60 g kg-1 clay and 0.5 g kg-1 organic matter in the top 0- 10 cm layer. The crops that were intercropped with blackberry were jack bean (Canavalia ensiformis) / oat (Avena strigosa) (JB-O); Brachiaria (Brachiaria decumbens) (BRA) and native grass (NG). The soil recuperation was measured by assessing the C and N stocks in the soil and biological indicators such as the enzymatic activity and soil fauna in relation to traditional grazing native grass (GNP). Results showed that intercropping of crops with blackberry improved soil biological conditions in relation to the GNP. Intercropping of JB-O with blackberry resulted in high dry matter production and C and N accumulation in shoots. Similarly, among the crops BRA appeared to be the crop that has potential to increase C and N stocks in the soils. This effect could be explained the rooting system of this grass. The presence of NG under blackberry helped to achieve average fruit yield and could be used as a strategy to establish the cultivation of blackberry in this region. Moreover, blackberry showed adaptation to the ecological conditions of the sandy soils and can be considered as an alternative crop for 1) recovering and reducing the outspread of sandification 2) as a possible source of income for the farmers of this region.
Na região sudoeste do Rio Grande do Sul (RS) existem extensas áreas com solos arenosos em processo de arenização. O objetivo deste estudo foi de avaliar o efeito de diferentes culturas intercalares a amoreira-preta sobre a recuperação de solo em processo de arenização e produtividade da cultura na região Sudoeste do RS, no município de São Francisco de Assis. O solo do experimento foi um Neossolo Quartzarênico típico com 60 g kg-1 de argila e 0,5 g kg-1 de matéria orgânica na camada de 0-10 cm. Os tratamentos avaliados nas entrelinhas da amoreira-preta foram os seguintes: feijão-de-porco (Canavalia ensiformis)/aveia preta (Avena strigosa) (FP-AP); Brachiaria (Brachiaria decumbens) (BRA); e campo nativo (CN). A recuperação do solo no pomar foi medida através da avaliação da recuperação dos estoques de C e N no solo e de indicadores biológicos como, a atividade enzimática e a fauna do solo em relação ao campo nativo sob pastejo tradicional (CN-T). Os tratamentos FP-AP, BRA e CN nas entrelinhas da amoreira-preta resultaram em melhora das condições biológicas do solo em relação ao CN-T. A combinação de feijão-de-porco e aveia-preta nas entrelinhas da amoreirapreta apresentou maior produção de matéria seca da parte aérea e acúmulo de C e N. A BRA foi a espécie que se destacou quanto a capacidade de promover o aumento do estoque de C e N no solo na entrelinha da amoreira-preta. Efeito esse devido possivelmente ao sistema radicular agressivo desta gramínea. A permanência do CN nas entrelinhas da amoreira-preta, além de permitir a obtenção de média produtividade de frutos, se apresenta como uma alternativa para a redução no custo de implantação e condução do pomar com essa espécie frutífera na região dos solos arenosos do sudoeste do RS. A amoreira-preta apresentou adaptação às condições edafoclimáticas dos solos arenosos do sudoeste do RS, podendo ser considerada como alternativa para a recuperação e redução do avanço das áreas arenizadas e também como uma possibilidade de fonte de renda para o produtor rural desta região do estado.
Mollard, Claire. "Modèles pour l'étude de l'assimilation du fer par les bactéries et les plantes : sidérophores abiotiques et processus d'échange." Université Joseph Fourier (Grenoble ; 1971-2015), 1997. http://www.theses.fr/1997GRE10295.
Full textMoncousin, Charles. "Évolution de l'AIA, des composés phénoliques, de l'activité spécifique des péroxydases et de la production d'éthylène, au cours de la rhizogénèse, sur des microboutures de vigne (V. Riparia Michx. X V. Rupestris Scheele)." Nancy 1, 1987. http://www.theses.fr/1987NAN10216.
Full textPoissonnier, Marie. "Étude expérimentale de la mycorhization in vitro de clones d'eucalyptus gunnii et eucalyptus gunnie x eucalyptus dalrympleana : Recherche de facteurs impliqués dans l'obtention de synthèses ectomycorhiziennes de ces clones par pisolithus tinctorius." Nancy 1, 1989. http://www.theses.fr/1989NAN10238.
Full textDominy, Carol Susan. "Comparative effects of sugarcane monoculture on soil organic matter status and soil biological activity." Thesis, 2002. http://hdl.handle.net/10413/4913.
Full textThesis (M.Sc.)- University of Natal, Pietermaritzburg, 2002.
Hwang, Jiann Lang, and 黃建郎. "The effect of fire on biological nitrogen fixation activity of Kuandashi forest soil." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/86330561629525204690.
Full textHellwig, Niels. "Spatial patterns of humus forms, soil organisms and soil biological activity at high mountain forest sites in the Italian Alps." Doctoral thesis, 2018. https://repositorium.ub.uni-osnabrueck.de/handle/urn:nbn:de:gbv:700-20181024676.
Full textCarvalho, Bruno Miguel Castro. "In vitro screening of the anticancer activity of marine and soil-derived fungi extracts and compounds used alone and combined with doxorubicin:evaluation of the anticancer properties of fungi extracts and compounds alone and in combination with doxorubicin in lung cancer cells." Dissertação, 2014. https://repositorio-aberto.up.pt/handle/10216/77835.
Full textCarvalho, Bruno Miguel Castro. "In vitro screening of the anticancer activity of marine and soil-derived fungi extracts and compounds used alone and combined with doxorubicin:evaluation of the anticancer properties of fungi extracts and compounds alone and in combination with doxorubicin in lung cancer cells." Master's thesis, 2014. https://repositorio-aberto.up.pt/handle/10216/77835.
Full text[Verfasser], Le-Thi-Thu-Huong. "Activity of fungal and bacterial endophytes for the biological control of the root-knot nematode Meloidogyne graminicola in rice under oxic and anoxic soil conditions / von Le Thi Thu Huong." 2010. http://d-nb.info/1005308233/34.
Full textPfeiffer, Birgit. "Impact of plant species, N fertilization and ecosystem engineers on the structure and function of soil microbial communities." Doctoral thesis, 2013. http://hdl.handle.net/11858/00-1735-0000-0022-5E3E-7.
Full textBaková, Izabela. "Izolace alkaloidů druhu Magnolia soulangeana Soul.-Bod. a studium jejich biologické aktivity." Master's thesis, 2017. http://www.nusl.cz/ntk/nusl-361795.
Full textHope, Sharon Margaret. "Biologic activity in two western Oregon Douglas-fir stands : a research link to management /." 1995. http://hdl.handle.net/1957/10877.
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