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Search Results: 1 - 10 of 16356 matches for " Ibanor;Carvalho "
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Diversidade metabólica e atividade microbiana no solo em sistema de integra??o lavoura-pecuária sob intensidades de pastejo
Chávez, Luis Fernando;Escobar, Luisa Fernanda;Anghinoni, Ibanor;Carvalho, Paulo César de Faccio;Meurer, Egon José;
Pesquisa Agropecuária Brasileira , 2011, DOI: 10.1590/S0100-204X2011001000020
Abstract: the objective of this work was to evaluate the metabolic diversity and the microbial activity in an integrated crop-livestock system under no-tillage, and at different grazing intensities and soybean production. the experiment was carried out in s?o miguel das miss?es county, in rio grande do sul state, brazil, in a clayey rhodic hapludox (oxisol), subjected to grazing intensities at 10, 20, 30 and 40 cm-height of pasture with black oat + italian ryegrass, and a nongrazing treatment, in the winter. the metabolic diversity was evaluated with the biolog ecoplate technique, by the shannon diversity index, and the microbial activity by the fluorescein diacetate hydrolysis method. there was higher functional diversity at the moderate grazing intensities (20 to 40 cm). the highest microbial activity, in the soil, occurred in the nongrazing treatment because of the high quantity of plant residues. microbial functional diversity and activity had alterations caused by the grazing intensities, which can be used as soil quality indicators on integrated crop-livestock systems under no-tillage.
Densidade, agrega??o e fra??es de carbono de um Argissolo sob pastagem natural submetida a níveis de ofertas de forragem por longo tempo
Conte, Osmar;Wesp, Cristiane de Lima;Anghinoni, Ibanor;Carvalho, Paulo César de Faccio;Levien, Renato;Nabinger, Carlos;
Revista Brasileira de Ciência do Solo , 2011, DOI: 10.1590/S0100-06832011000200027
Abstract: the adjustment of animal quantity according to the herbage allowance is fundamental to the sustainability of natural pastures. the management of herbage allowance, besides affecting the plant species that compose the pasture, can also compromise soil properties, such as density and aggregation. this study aimed to evaluate the soil bulk density, weighted mean diameter of soil aggregates and carbon fractions under natural pasture, under varying grazing intensities for 22 years, represented by herbage allowance levels of 4, 8, 12, and 16 kg dry matter per 100 kg animal weight. two ungrazed areas were included as references. changes in soil properties were found, related to the grazing intensity. these changes occurred mainly in the soil surface layer (0-10 cm), where soil density increased with decreasing herbage allowance. the behavior of the weighted mean diameter of soil aggregates and the root mass in the layer 0 - 10 cm were inversely proportional to the herbage allowance. the carbon storage index indicated that under forage supplies of 12 % the soil c stock increased compared to the control, but decreased at other allowance rates. the index of carbon management shows that the highest herbage allowance (12 and 16 %) improved the system quality of natural pasture, while at the lowest allowance rate (4 %) the system lost quality and sustainability, as demonstrated by the substantial reduction of this index.
Ciclagem e balan?o de potássio e produtividade de soja na integra??o lavoura-pecuária sob semeadura direta
Ferreira, Eric Victor de Oliveira;Anghinoni, Ibanor;Andrighetti, Marcelo Hoerbe;Martins, Amanda Posselt;Carvalho, Paulo César de Faccio;
Revista Brasileira de Ciência do Solo , 2011, DOI: 10.1590/S0100-06832011000100015
Abstract: nutrient cycling and balance in integrated crop-livestock systems (icl) are processes that involves soil, plant and animal components, beyond fertilization. animal management, by modifying soil biotic and abiotic conditions, also influences this process as it affects the residue decomposition rate. the objective was to evaluate potassium (k) cycling and balance in an icl system with grazing (black oat and ryegrass) intensities in the winter, followed by soybean cultivated in the summer. the experiment was conducted as of may of 2001 in an area in the state of rio grande do sul - brazil, on a rhodic hapludox (oxisol), under no tillage since 1991. the treatments consisted of continuous bovine grazing intensities at a pasture height of 10, 20, 30 and 40 cm, and a control (no-grazing), in a randomized block design, with three replicates. the forage/soybean cycle of 2007/08 was evaluated in this paper. to calculate k cycling, the contents accumulated in pasture, soybean and animals in one pasture-soybean cycle were considered, and the balance, "in the field" and "in the soil", of k inputs (fertilizer) and outputs (soybean grains and animal tissue) and the k remaining in plant and soil, respectively, were calculated. potassium cycling increased with increasing grazing intensity and the balance, despite negative, with a higher deficit in areas with higher grazing intensity, did not influence soybean yield.
Atributos químicos do solo em fun??o da aplica??o superficial de calcário em sistema de integra??o lavoura-pecuária submetido a press?es de pastejo em plantio direto
Flores, Jo?o Paulo Cassol;Cassol, Luis César;Anghinoni, Ibanor;Carvalho, Paulo César de Faccio;
Revista Brasileira de Ciência do Solo , 2008, DOI: 10.1590/S0100-06832008000600017
Abstract: the use of large areas occupied only with winter soil cover crops for cattle grazing may become an alternative income source for summer grain producers in southern brazil. the presence of cattle in areas used only with no tillage crops may, however, affect soil attributes, depending on the management type. this study aimed to evaluate the effects of surface liming on the chemical attributes of a red latosol (oxisol) under no-tillage and crop-livestock integration. treatments consisted of pasture management at different heights (10, 20, 30 and 40 cm), in addition to areas without grazing, during the winter. in december 2001, the soil (layers of 0-25, 2.5-5, 5-7,5, 7,5-10, 10-12,5, 12,5-15, 15-17,5, 17,5-20 and 20-25 cm) was evaluated for chemical properties after the first grazing cycle. thereafter, 4.5 mg ha-1 limestone (62 % effective neutralization value) was broadcast and left on soil surface and soybean grown in succession to grazing. soil samples were colleted at the end of the first, second, third, fourth and fifth soybean growing seasons, corresponding to 6, 12, 24, 36, and 48 months after liming. the following variables were evaluated: ph-h2o, smp, exchangeable ca, mg, k and al, and total organic carbon (toc). the surface lime application was effective in correcting the acidity to a depth of 25 cm, depending on the attribute and variable over time. the presence of cattle grazing in the area increased the depth effect of liming. the input of different residues to the soil did not affect the toc levels.
Critérios de calagem para a soja no sistema plantio direto consolidado
Nolla, Antonio;Anghinoni, Ibanor;
Revista Brasileira de Ciência do Solo , 2006, DOI: 10.1590/S0100-06832006000300009
Abstract: lime recommendations developed for conventional systems are being used in no-tillage systems with different dynamics of the acidity attributes, due to organic matter and nutrient accumulation on the superficial layer and lower aluminum toxicity. this study associated different acidity indicators of a rhodic hapludox after eight years under no-tillage system with soybean plant characteristics in order to establish liming criteria. two field experiments were compared, both under no-tillage for eight years; one had previously been under conventional tillage and the other under natural pasture, and presented different acidity levels owing to previous liming. undisturbed soil samples were collected in pvc columns, in which the soybean plants were grown for 25 days. lime criteria were obtained by derivation of equations relating soybean grain yield and plant characteristics with the following soil acidity indicators: water and cacl2 ph, exchangeable aluminum, aluminum saturation, exchangeable al/ca + mg ratio and base saturation. a ph in water of 5.5 and base saturation of 62 % were the most suitable liming criteria for soil samples from the 0 to 15 cm as well as from the 0 to 10 cm depth soil layers. liming criteria can also be determined, in the short term, by growing plants in undisturbed soil columns, preferentially using root characteristics.
Atividade e especia??o química na solu??o afetadas pela adi??o de fósforo em latossolo sob plantio direto em diferentes condi??es de acidez
Nolla, Antonio;Anghinoni, Ibanor;
Revista Brasileira de Ciência do Solo , 2006, DOI: 10.1590/S0100-06832006000600005
Abstract: in no-tillage systems, crop residues and nutrients, namely phosphorus and calcium, accumulate in soil surface and can inactivate soil aluminum. in this way, only the presence of this element in soil analysis does not indicate plant toxicity, since organic and inorganic anions may affect the free aluminum dynamics by decreasing its activity in the soil solution. knowledge on ion activity and speciation in soil solution is therefore useful to understand al dynamics. ionic activity and speciation were determined in the soil solution of an oxisol (rhodic hapludox), under no-tillage for the seven preceding years and different acidity conditions due to previous applications of variable lime rates in 1994. after the chemical characterization of the study soil, undisturbed samples were collected in pvc columns and subjected to surface application of different phosphorus rates (0, 40, 80, 160, 320, 640, 1.280, and 2.560 mg l-1 of p in solution) and then incubated for 30 days. soil solution was directly extracted from the tubes by centrifugation and acidity attributes and cations and anions were determined to estimate ionic activity and speciation using a visual minteq a2 program. a decrease in aluminum content and activity in soil solution after phosphorus application was observed. the increase of phosphorus in soil solution did not directly affect aluminum inactivation, because no aluminum phosphates were formed. the increase of phosphorus in soil solution, however, displaced organic and inorganic anions that were effective in aluminum complexation in soil solution.
Sistema de integra??o lavoura-pecuária: desempenho e qualidade da carca?a de novilhos superprecoces terminados em pastagem de aveia e azevém manejada sob diferentes alturas
Lopes, Marília Lazzarotto Terra;Carvalho, Paulo César de Faccio;Anghinoni, Ibanor;Santos, Davi Teixeira dos;Kuss, Fernando;Freitas, Fabiana Kellermann de;Flores, Jo?o Paulo Cassol;
Ciência Rural , 2008, DOI: 10.1590/S0103-84782008000100029
Abstract: this trial aimed at evaluating the performance and carcass quality of superprecoce steers grazing oat and annual ryegrass pastures managed at 10, 20, 30 and 40cm height, and supplemented at the final third of the grazing cicle. young animals with 10 months on average and initial weight of 190kg were distributed in a randomized block design with three replicates. the herbage allowances were 8.8, 14.7, 29.0 and 48.9kg of dry matter 100kg of live weight-1 (lw), respectively for the treatments 10, 20, 30 and 40cm. the live weight gain per hectare was superior in treatments with lower heights, due to the increased stocking rate, being 529.7, 489.5, 320.9 and 201.6kg of lw, respectively for 10, 20, 30 and 40cm height. the average daily gain and slaughter weight increased with pasture height being fitted by a quadratic model (p<0.05). the fat deposition and the medium dressing of cold carcass averaged 3.8mm and 53.3%, respectively (p>0.05). superprecoce steers reached slaughter weight and adequately finishing degree when finished in winter cultivated pasture supplemented in final third of grazing cicle. better individual animal performance was obtained when pasture height ranges from 25 to 30cm, and animal production per hectare when the pasture was managed at 10 cm height.
Desempenho e características das carca?as de novilhos superprecoces em pastos hibernais submetidos a intensidades de pastejo
Rocha, Lemar Maciel da;Carvalho, Paulo César de Faccio;Baggio, Carolina;Anghinoni, Ibanor;Lopes, Marília Lazzarotto Terra;Macari, Stefani;Silva, Jamir Luis Silva da;
Pesquisa Agropecuária Brasileira , 2011, DOI: 10.1590/S0100-204X2011001000035
Abstract: the objective of this work was to assess the grazing intensity effects on the finishing of yearling bulls, in winter pastures in succession to soybean crop. sward pre-grazing different heights of mixed pasture between ryegrass and oat were evaluated: 10, 20, 30 and 40 cm. a randomized complete block design was utilized with three replicates. ten-month-old beef crossbred bulls were used, with initial live weight of 192±12 kg. the following variables were evaluated: forage mass and allowance, sward height, forage daily accumulation rate and forage total accumulation, average daily weight gain (adg), stocking rate and weight gain per unit area (ga), as well as the qualitative characteristics of the carcasses. the yearling bulls were slaughtered at 14 months of age. adg fitted a quadratic model, with maximum performance between 20 and 25-cm sward height, while ga fitted a negative linear model. yearling bulls showed a satisfactory carcass quality when pastures were managed with pre-grazing heights higher than 10 cm. it is possible to finish yearling bulls in the pasture phase of integrated production systems, during winter, in succession to soybean crop. the management of ryegrass and oat mixed pastures at sward pre-grazing heights of 20 and 25 cm optimize individual animal performance and per area unit.
Evolu??o de atributos físicos de solo em sistema de integra??o lavoura-pecuária
Conte, Osmar;Flores, Jo?o Paulo Cassol;Cassol, Luís César;Anghinoni, Ibanor;Carvalho, Paulo César de Faccio;Levien, Renato;Wesp, Cristiane de Lima;
Pesquisa Agropecuária Brasileira , 2011, DOI: 10.1590/S0100-204X2011001000026
Abstract: the objective of this work was to assess the effect of sward height and successive grazing cycles over soil physical attributes in an integrated crop-livestock system. the experiment was established in 2001, in the planalto médio region, rs, brazil, in a rhodic hapludox (oxisol), with annual ryegrass (lolium multiflorum) intercropped with black oat (avena strigosa), under continuous grazing, during the winter, and single cropped soybean (glycine max) during the summer. the treatments consisted of different grazing intensities, determined by sward height (10, 20, 30, and 40 cm), and a no-grazing area was used as a control. soil bulk density and soil porosity were evaluated at the end of the grazing and soybean cycles, as well as soil resistance to mechanic penetration and aggregate stability in the seventh year of the experiment. no significant differences were found on soil bulk density and soil porosity after seven years under crop-livestock integration. soil resistance to penetration is higher on the superficial layer after the grazing cycle. soil aggregation increases in grazing areas, regardless of grazing intensities.
Atributos físicos do solo e rendimento de soja em sistema plantio direto em integra??o lavoura-pecuária com diferentes press?es de pastejo
Flores, Jo?o Paulo Cassol;Anghinoni, Ibanor;Cassol, Luis César;Carvalho, Paulo César de Faccio;Leite, Jo?o Guilherme Dal Belo;Fraga, Thiago Isquierdo;
Revista Brasileira de Ciência do Solo , 2007, DOI: 10.1590/S0100-06832007000400017
Abstract: the integration of farming and cattle production activities in no-tillage system areas with winter cover crops can be an income supplement for summer grain farmers. however, many of them are afraid of adopting this integration system, because of possible negative effects of animal treading on soil attributes, mainly of those related to soil compaction. this study was conducted: (1) to determine the alterations in the soil physical attributes promoted by animal treading; (2) to verify if the alterations in soil attributes due to animal treading affect soybean establishment and grain yield. the experiment was carried out with a rhodic hapludox (oxisol), under black oat + ryegrass pasture grazed at different heights (10, 20, 30 and 40 cm) and an ungrazed area. after one cycle of animal treading there were no significant modifications in soil bulk density, porosity and compressibility at different grazing heights. however, soil density and compressibility were higher and the porosity lower in the grazed plots. the soybean population and grain yield were not affected by modifications in the soil physical attributes.
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