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Registros recuperados: 101 | |
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Arnberg, Soren; Hansen, Lars Garn. |
This study develops a dynamic multi-output model of farmers crop allocation decisions that allows estimation of both short-run and long-run adjustments to a wide array of economic incentives. The method can be used to inform decision makers on a number of issues including agricultural policy reform and environmental regulation. The model allows estimation of dynamic effects relating to price expectations adjustment, investment lags, and crop rotation constraints. Estimation is based on micro-panel data from Danish farmers that includes acreage, output, and variable input utilization at the crop level. Results indicate that there are substantial differences between the short- and long-run land allocation behavior of Danish farmers and that there are... |
Tipo: Conference Paper or Presentation |
Palavras-chave: Land allocation; Crop rotation; System of dynamic equations; Micro panel data; GMM; Land Economics/Use; C33; Q12; Q15. |
Ano: 2007 |
URL: http://purl.umn.edu/9978 |
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Chung, S.W.; Gassman, Philip W.; Huggins, David R.; Randall, G.W.. |
The Erosion Productivity Impact Calculator (EPIC) model was tested using four years of field data collected at a site near Lamberton, Minnesota, under three different crop rotations: continuous corn (Zea mays L.) or CC, soybean (Glycine max L.)-corn (SC), continuous alfalfa (Medicago sativa L.) or CA. The model was evaluated by comparing measured versus predicted subsurface drainage flow (tile flow), nitrate-nitrogen (NO3-N) loss in tile flow, residual NO3-N in the soil profile, crop N uptake, and yield. Initially, EPIC was run using standard Soil Conservation Service (SCS) runoff curve numbers (CN2) suggested for the soil type at the site. Two different SC runs were performed with a nitrogen fixation parameter denoted as parm(7) set at either 1.0 or 0.3,... |
Tipo: Working or Discussion Paper |
Palavras-chave: Modeling; Water quality; Crop rotation; Tile drainage; Nitrate leaching; Fertilizer; Crop Production/Industries. |
Ano: 2000 |
URL: http://purl.umn.edu/18479 |
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Tavares Filho,João; Guimarães,Maria de Fátima; Curmi,Pierre; Tessier,Daniel. |
It is known that any kind of soil management causes changes in the soil physical characteristics and can affect agricultural yield. The purpose of this study was to evaluate soil properties of an Alfisol and soybean yield under different management systems for no-tillage annual crops, no-tillage with chiseling and no-tillage crop rotation. The 11-year experiment was initiated in the 1998/99 growing season, on 100 x 30 m plots (11 % slope). Soil samples (5 per management system) were systematically collected (0-25 cm layer) in the summer growing season, to quantify soil organic matter, bulk density, macroporosity and flocculation, as well as soybean yield. The highest values for soil bulk density and organic matter content and the lowest for macroporosity... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: No tillage; Soil physical properties; Organic matter; Crop rotation. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000100026 |
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Andrade,Andréia Patrícia; Mafra,Álvaro Luiz; Baldo,Gizele Rejane; Piccolla,Cristiano Dela; Bertol,Ildegardis; Albuquerque,Jackson Adriano. |
Soil is the basis underlying the food production chain and it is fundamental to improve and conserve its productive capacity. Imbalanced exploitation can degrade agricultural areas physical, chemical and biologically. The objective of this study was to evaluate some soil physical properties and their relation with organic carbon contents of a Humic Dystrudept under conventional tillage (CT) and no-tillage (NT), for 12 years in rotation (r) and succession (s) cropping systems. The experiment was carried out in Lages, SC (latitude 27 º 49 ' S and longitude 50 º 20 ' W, 937 m asl), using crop sequences of bean-fallow-maize-fallow-soybean in conventional tillage rotation; maize-fallow in conventional tillage succession; bean-oat-maize-turnip-soybean-vetch in... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Crop rotation; Crop succession; No-tillage; Soil management. |
Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832010000100022 |
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Ciancio,Nathalia Riveros; Ceretta,Carlos Alberto; Lourenzi,Cledimar Rogério; Ferreira,Paulo Ademar Avelar; Trentin,Gustavo; Lorensini,Felipe; Tiecher,Tadeu Luis; De Conti,Lessandro; Girotto,Eduardo; Brunetto,Gustavo. |
Animal manure is applied to the soil as a nutrient source, especially of nitrogen, to plants. However, manure application rates can be reduced with the use of N fertilizer in topdressing. The aim of this study was to evaluate crop responses to different application rates of animal manure sources, used alone and supplemented with mineral N topdressing, in a no-tillage system. The study was carried out from 2005 to 2008 on a Hapludalf soil. The treatments consisted of rates of 10, 20 and 30 m³ ha-1 of pig slurry (PS), and of 1 and 2 t ha-1 of turkey manure (TM), applied alone and supplemented with topdressed N fertilizer (TNF), as well as two controls, mineral fertilization (NPK) and one control without fertilizer application. Grain yield in common bean and... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Animal manure; Crop rotation; No-tillage cropping system. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000300023 |
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Seben Junior,Getulio de Freitas; Corá,José Eduardo; Lal,Rattan. |
The no-till system with complex cropping sequences may improve the structural quality and carbon (C) sequestration in soils of the tropics. Thus, the objective of this study was to evaluate the effects of cropping sequences after eight years under the no-till system on the physical properties and C sequestration in an Oxisol in the municipality of Jaboticabal, Sao Paulo, Brazil. A randomized split-block design with three replications was used. The treatments were combinations of three summer cropping sequences - corn/corn (Zea mays L.) (CC), soybean/soybean (Glycine max L. Merryll) (SS), and soybean-corn (SC); and seven winter crops - corn, sunflower (Helianthus annuus L.), oilseed radish (Raphanus sativus L.), pearl millet (Pennisetum americanum (L.)... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cerrado; Crop rotation; Winter crops; Soil aggregates; Least limiting water range; Bulk density. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000400023 |
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Tirloni,Carolina; Vitorino,Antonio Carlos Tadeu; Bergamin,Anderson Cristian; Souza,Luiz Carlos Ferreira de. |
Crop-livestock integration represents an interesting alternative of soil management, especially in regions where the maintenance of cover crops in no-tillage systems is difficult. The objective of this study was to evaluate soil physical and chemical properties, based on the hypothesis that a well-managed crop-livestock integration system improves the soil quality and stabilizes the system. The experiment was set up in a completely randomized design, with five replications. The treatments were arranged in a 6 x 4 factorial design, to assess five crop rotation systems in crop-livestock integration, and native forest as reference of soil undisturbed by agriculture, in four layers (0.0-0.05; 0.05-0.10; 0.10-0.15 and 0.15-0.20 m). The crop rotation systems in... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Crop rotation; No-tillage system; Soil quality; Soil carbon; Aggregate stability. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000400024 |
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Marcelo,Adolfo Valente; Corá,José Eduardo; Fernandes,Carolina; Martins,Márcio dos Reis; Jorge,Ricardo Falqueto. |
Decomposing crop residues in no-tillage system can alter soil chemical properties, which may consequently influence the productivity of succession crops. The objective of this study was to evaluate soil chemical properties and soybean, maize and rice yield, grown in the summer, after winter crops in a no-tillage system. The experiment was carried out in Jaboticabal, SP, Brazil (21 ° 15 ' 22 '' S; 48 ° 18 ' 58 '' W) on a Red Latosol (Oxisol), in a completely randomized block design, in strip plots with three replications. The treatments consisted of four summer crop sequences (maize monocrop, soybean monocrop, soybean/maize rotation and rice/bean/cotton rotation) combined with seven winter crops (maize, sunflower, oilseed radish, pearl millet, pigeon pea,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Winter crops; Crop rotation; Cover crops; Soil management. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832009000200019 |
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Lourenzi,Cledimar Rogério; Ceretta,Carlos Alberto; Brunetto,Gustavo; Girotto,Eduardo; Tiecher,Tadeu Luis; Vieira,Renan Costa Beber; Cancian,Adriana; Ferreira,Paulo Ademar Avelar. |
Pig slurry (PS) represents an important nutrient source for plants and using it as fertilizer makes greater nutrient cycling in the environment possible. The aim of this study was to assess how PS application over a period of years can affect grain yield, dry matter production and nutrient accumulation in commercial grain and cover crops. The experiment was carried out in an experimental area of the Universidade Federal de Santa Maria, in Santa Maria, RS, Brazil, from May 2000 to January 2008. In this period, 19 grain and cover crops were grown with PS application before sowing, at rates of 0, 20, 40 and 80 m³ ha-1. The highest PS rate led to an increase in nutrient availability over the years, notably of P, but also of nutrients that are potentially toxic... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Manure; Yield; Crop rotation. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000300027 |
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Queiroz,Rienni de Paula; Lazarini,Edson; Santos,Marcio Lustosa; Carvalho,Morel de Passos e; Santos,Cristiano. |
The Cerrado (Brazilian Savannah) plays an important economic and financial role in the nation, since the pastures of this biome feed cattle for half of the domestic bovine meat productivity, and its agricultural fields produce a third of the country's grain. The variability and spatial dependence between the soil physical attributes and soybean yield were evaluated in a crop rotation planted on a degraded brachiaria pasture, on a dystroferric Red Latosol of an experimental farm of the State University of São Paulo (UNESP), in the 2005/2006 growing season. The linear and spatial correlations between these attributes were also studied, to determine conditions that would allow increased agricultural productivity. In the above pasture area, a grid was... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil conservation; Crop rotation; Pasture management; Glycine max (L.) Merrill; Spatial variability. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832011000500012 |
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Registros recuperados: 101 | |
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