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| Registros recuperados: 232 | |
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| Maeda, Shizuo; Bognola, Itamar Antonio. |
| O efeito da aplicação combinada de calagem, fontes de fósforo e forma de aplicação das fontes no crescimento e absorção de fósforo em mudas de Eucalyptus dunnii foi estudado em condições de vaso. O experimento foi conduzido em casa-de-vegetação não climatizada, utilizando um Cambissolo Húmico Ta Alumínico Típico, durante 67 dias. Os tratamentos consistiram na combinação de dois níveis de calagem (C0, sem calagem e C1, dose para elevar o pH em água a 5,5 pelo método do pH SMP), duas fontes de fósforo (superfosfato triplo e fosfato natural de Gafsa) e dois modos de aplicação das fontes de fósforo (incorporada e localizada). A calagem aumentou a produção de matéria seca da parte aérea, o crescimento das mudas, o acúmulo e a eficiência de uso do P no... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fontes de fósforo; Calagem; Fertilidade do solo Phosphorus sources; Liming; Soil fertility. |
| Ano: 2011 |
URL: http://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/302 |
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| Neves, Edinelson José Maciel; Santos, Álvaro Figueredo dos; Martins, Emerson Gonçalves; Ahrens, Sérgio; Kalil Filho, Antonio Nascim. |
| An experiment was established in Paranaguá, located in the costal region of the State of Paraná, in southern Brasil, in order to evaluate commercial yield of hearth-of-palm produced by Peach-Palm (Bactris gasipaes) established under the following four different initial spacings: T1 2x1m (5000 seedlings/ha); T2 3x1m (3333 seedlings/ha); T3 1,5x1x1m (8000 seedlings/ha); and T4 2x1x1m (6666 seedlings/ha). Mineral fertilizers (NPK) were applied at planting as well as subsequently. Results obtained by the time of the first cutting, 24 months after planting, allowed the following conclusions: a) the quantities of the NPK fertilizer used promoted changes in the chemical soil characteristics; b) commercial yield of hearth-of-palm improved as a function of stand... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil fertility; Fertilization; Commercial yield Fertilidade do solo; Adubação; Produção industrial. |
| Ano: 2003 |
URL: http://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/1619 |
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| Andrade, Guilherme de Castro; Bognola, Itamar Antonio; Bellote, Antonio Francisco Jurado; Franciscon, Luziane; Waterloo, Maarten Johannes; Bruijnzeel, Leendert Adriaan. |
| No Brasil os plantios florestais ocupam 7 milhões de hectares que correspondem a 1% do território (68% com plantações de Eucalyptus e 25% com Pinus) O objetivo desse trabalho foi avaliar plantios de Eucalyptus urograndis. Estoques elevados de Ca e Mg no solo, sugerem uma lixiviação do calcário. A resistência do solo até os 60 cm de profundidade na linha de plantio foi menor do que na entrelinha, indicando que a subsolagem foi eficiente. Os valores de resistência do solo foram mais altos na entrelinha, distante 1 m da linha de plantio, até os 20 cm de profundidade, provavelmente pelo aumento da compactação na preparação da área. A biomassa da copa das árvores diferiu entre as classes de DAP, justificando o uso de equação para a sua estimativa. A variação... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Forest plantation; Biomass; Litter; Soil fertility; Soil strength Plantação florestal; Biomassa; Serapilheira Fertilidade do solo; Resistência do solo. |
| Ano: 2011 |
URL: http://pfb.cnpf.embrapa.br/pfb/index.php/pfb/article/view/273 |
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| Costa,Claudio Hideo Martins da; Crusciol,Carlos Alexandre Costa; Ferrari Neto,Jayme; Castro,Gustavo Spadotti Amaral. |
| Abstract The objective of this work was to evaluate the long-term effects of the surface application of lime on soil fertility and on the mineral nutrition and grain yield of soybean, and of black oat and sorghum in crop succession. The experiment was carried out on a clayey Oxisol, in a randomized complete block design, with four replicates. Treatments consisted of lime the rates of 0, 1,000, 2,000, and 4,000 kg ha-1, applied in October 2002 and November 2004. Soil samples were collected at five soil layers, down to 0.60-m depth. Surface liming was effective in reducing soil acidity and increasing Ca2+ and Mg2+ contents in the subsurface. Moreover, it increased available phosphorus contents and soil organic matter in the long term (48 to 60 months after... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Crop rotation; Long-term experiment; Plant nutrition; Soil fertility; Subsurface soil acidity; Yield components. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2016000901633 |
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| Vendrame,Pedro Rodolfo Siqueira; Marchão,Robélio Leandro; Brito,Osmar Rodrigues; Guimarães,Maria de Fátima; Becquer,Thierry. |
| The objective of this work was to assess the relationship between macrofauna, mineralogy and exchangeable calcium and magnesium in Cerrado Oxisols under pasture. Twelve collection points were chosen in the Distrito Federal and in Formosa municipality, Goiás state, Brazil, representing four soil groups with varied levels of calcium + magnesium and kaolinite/(kaolinite + gibbsite) ratios. Soil macrofauna was collected in triplicate at each collection point, and identified at the level of taxonomic groups. Macrofauna density showed correlation with contents of kaolinite, gibbsite and exchangeable Ca + Mg in the soils. Mineralogy and exchangeable Ca + Mg had significant effects on taxonomic groups and relative density of soil macrofauna. The termites... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Gibbsite; Kaolinite; Soil fauna; Soil fertility; Total carbon. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2009000800031 |
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| Souza,Géssica Pereira de; Figueiredo,Cícero Célio de; Sousa,Djalma Martinhão Gomes de. |
| Abstract The objective of this work was to evaluate the effects of soil management systems, cover crops, and phosphate fertilization on soil humic fractions in a long-term experiment. The treatments consisted of conventional tillage and no-tillage with pearl millet (Pennisetum glaucum) or velvet bean (Mucuna aterrima) as cover crops, at two doses of phosphorous: 0 and 100 kg ha-1 P2O5 per year. Soil samples were taken 11 years after the establishment of the experiment and analyzed for soil total organic carbon and carbon content of humic fractions at 0.00-0.05, 0.05-0.10, and 0.10-0.20-m depths. The humic fractions are sensitive to soil management, except free fulvic acid, which was the only one that did not reduce its carbon contents on the surface layer... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Humic fractions; No-tillage; Organic matter fractions; Phosphate fertilization; Soil fertility; Soil quality. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2016000901668 |
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| Corassa,Geomar Mateus; Santi,Antônio Luís; Silva,Vanderlei Rodrigues da; Baron,Felipe Arthur; Reimche,Geovane Boschmann; Fioresi,Dejales; Flora,Diandra Pinto Della. |
| Abstract: The objective of this work was to identify soil chemical attributes restricting grain yield in Oxisols under the no-tillage system, using directed soil sampling. High, medium, and low yield zones were defined in two agricultural fields using historical yield data of several crops. The yield zones were defined based on the harvest maps of the following crops: corn in 2008/2009, white oat in 2009, and corn in 2012/2013 in field I, with 117.70 ha; and corn in 2009/2010, soybean in 2010/2011, and wheat in 2012 in field II, with 107.30 ha. Soil sampling points were georeferenced in each yield zone, where samples were collected at eight soil depths, spaced 0.05 m apart, totaling 80 variables. Low yields were associated with low cation exchange... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Organic matter; Precision agriculture; Site-specific management; Soil fertility; Soil sampling; Yield zones. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2018001101203 |
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| Fuentes,Luis Felipe Garcia; Souza,Luiz Carlos Ferreira de; Serra,Ademar Pereira; Rech,Jerusa; Vitorino,Antonio Carlos Tadeu. |
| Abstract: The objective of this work was to evaluate corn agronomic traits in a cultivation subjected to different N rates, during the fall-winter (off-season) and spring-summer crop seasons, and N recovery from fertilizer. The experiment was set up in a randomized complete block design with four replicates, in a 5x2 factorial arrangement, with the following treatments: five N topdressing rates - 0, 30, 60, 90, and 120 kg ha-1 -, using urea as source; and two crop seasons, fall-winter and spring-summer. The following variables were determined: plant height, height of the first ear insertion, number of grains per ear, diameter and length of ear, 1,000-grain weight, N concentration in the leaves and grains, grain-protein concentration, grain yield, N... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Zea mays; N-fertilizer management; Plant nutrition; Soil fertility; Soil-N supply. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2018001001158 |
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| Novotny,Etelvino Henrique; Auccaise,Ruben; Velloso,Marcia Helena Rodrigues; Corrêa,Juliano Corulli; Higarashi,Martha Mayumi; Abreu,Valéria Maria Nascimento; Rocha,José Dilcio; Kwapinski,Witold. |
| The objective of this work was to develop an alternative methodology to study and characterize the phosphate crystalline properties, directly associated with solubility and plant availability, in biochar from swine bones. Some phosphate symmetry properties of pyrolyzed swine bones were established, using solid state nuclear magnetic resonance spectroscopy, principal component analysis, and multivariate curve resolution analysis, on four pyrolyzed samples at different carbonization intensities. Increasing carbonization parameters (temperature or residence time) generates diverse phosphate structures, increasing their symmetry and decreasing the crossed polarizability of the pair ¹H-31P, producing phosphates with, probably, lower solubility than the ones... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bone phosphate; Phosphate availability; Principal component analysis; Pyrolysis; Multivariedade curve resolution analysis; Soil fertility. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2012000500006 |
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| Veiga,Milton da; Pandolfo,Carla Maria; Balbinot Junior,Alvadi Antonio; Spagnollo,Evandro. |
| The objective of this study was to evaluate the pig slurry application effects on chemical attributes of a Hapludox soil managed under no-tillage system. Treatments consisted of 50, 100 and 200 m³ ha-1 per year of pig slurry application, and a control with replacement of P and K exported through harvested grains. Attributes related to soil chemical reaction, exchange complex, and nutrient contents were determined in soil samples collected in the ninth year of experimentation from 0 - 0.025, 0.025 - 0.05, 0.05 - 0.10, 0.10 - 0.20, 0.20 - 0.40 and 0.40 - 0.60 m soil depths. The continuous application of high doses of pig slurry on the Oxisol surface under no-tillage acidifies the soil and increases Al, P, Cu, and Zn contents down to 0.2-m depth, and K levels... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Acidification; Micronutrients; No-tillage system; Soil fertility; Soil pollution; Soil quality. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2012001200013 |
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| ULLAH,R.; ASLAM,Z.; KHALIQ,A.; ZAHIR,Z.A.. |
| ABSTRACT: Continuous and excessive use of herbicides to control various weed biotypes is posing severe threats to soil and human health. Nevertheless, the strategy of using allelopathic crop residues and water extracts for weed control seems to be a sustainable and friendly option to reduce dependence on synthetic herbicides. In addition to controlling weeds, residues of allelopathic crops positively affected soil health. A two-year field study was carried out to examine the impact of sunflower residues on soil properties, weed dynamics and productivity of mung bean. The study was comprised of five treatments viz., control, sunflower water extracts at 10 and 20 L ha-1, and sunflower residues incorporation at 4 and 6 ton ha-1. Results indicated that... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allelopathy; Soil fertility; Soil enzymes; Crop residues. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100258 |
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| Place, Frank; Franzel, Steven Charles; Noordin, Qureish; Jama, Bashir. |
| This case study explores the development, dissemination, adoption, and impact of improved tree fallows in rural western Kenya. The processes of technology development and dissemination throughout the region are described and analyzed. To analyze adoption and impact, the paper applies a variety of different data collection methods as well as samples from both pilot areas where researchers maintained a significant presence and non-pilot areas where farmers learned of the technologies through other channels. Sample sizes for the quantitative analysis ranged from almost 2,000 households for measuring the adoption process to just over 100 households for measuring impact indicators. Qualitative methods included long-term case studies for 40 households and focus... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Agroforestry; Soil fertility; Kenya; Adoption; Impact; Technology; Farm Management. |
| Ano: 2004 |
URL: http://purl.umn.edu/16054 |
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| Place, Frank; Adato, Michelle; Hebinck, Paul; Omosa, Mary. |
| For decades, there has been significant investment in the development of agricultural technologies that aim to increase productivity of smallholder farms in Africa. At a macro-level, however, farm output and productivity have stagnated and poverty rates have remained stubbornly high, even increasing in some areas. It is widely acknowledged that policy and infrastructural constraints play a large role in reducing incentives for farmers to invest in agriculture. Yet the fact that farmers have made some investments and that some progress has occurred suggests that characteristics of the technologies themselves, or the way in which they are promoted, also facilitate or inhibit wider adoption and impact. This research report, part of a set of studies on the... |
| Tipo: Report |
Palavras-chave: Soil fertility; Kenya; Agroforestry extension; Agroforestry projects; Crop Production/Industries; Land Economics/Use. |
| Ano: 2005 |
URL: http://purl.umn.edu/37888 |
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| Bellon, Mauricio R.; Gambara, Peter; Gatsi, Tendai; MacHemedze, Timothy E.; Maminimini, Obert; Waddington, Stephen R.. |
| Soil infertility is a major constraint to food production in the communal areas of Zimbabwe. Smallholders in the region recognize the problems of low soil fertility and have devised ways of coping with them. This study describes the use of farmers taxonomies of themselves and their soils to identify and understand the options they have, and the constraints they face in managing poor soil fertility in Chihota, a sub-humid communal area of north central Zimbabwe. It is part of an effort by a group of agricultural researchers and extensionists working on improved soil fertility technologies, to better integrate their work with farmers in order to expose the latter to promising technologies, get feedback on the technologies merits and feasibility, and help... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Participatory methods; Soil fertility; Local taxonomies; Smallholders; Zimbabwe; Farm Management; Land Economics/Use. |
| Ano: 1999 |
URL: http://purl.umn.edu/7677 |
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| Registros recuperados: 232 | |
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