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INDICE AGRARIO
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PRECISION AGRICULTURE


Economics of Variable Rate Lime In Indiana (Look this paper in the category: Ensayos a Campo)

Abstract: “In Indiana, variable rate application (VRA) of lime is often considered a good place to start site-specific management (SSM). This is because soil pH is one of the most variable of manageable soil characteristics in the state, the availability of essential nutrients is closely related to soil pH, and because spreaders can be retrofitted relatively inexpensively to do VRA. The objective of this study is to evaluate the profitability of VRA for lime as a standalone activity. The methodology involves a spreadsheet model using corn and soybean pH response functions estimated with small plot data. The overall results indicate increased annual returns to corn and soybean production with site-specific pH management strategies.  On average, SSM with agronomic recommendations provides an increased annual return of $7.24 per hectare (ha) (+1.78%). SSM with the economic decision rule provides an average increase in annual return of $19.55 ha-1 (+4.82%). Information strategy, which uses sitespecific information to determine the economically optimal uniform rate of lime, provides an average increase in annual return of $14.38 ha-1 (+3.54%)”.

Authors: Rodolfo Bongiovanni (Proyecto Agricultura de Precisión, INTA Manfredi), J. Lowenberg-DeBoer (Universidad de Purdue). Source: Agricultura de Precisión, Manfredi, Córdoba, Argentina.  Consult other works in Spanish of the same institution in:  INDICE AGRARIO: AGRICULTURA DE PRECISION.

 

Economics of Variable Rate Planting for Corn (Look this paper in the category: Ensayos a Campo)

Abstract: “This analysis works out the economic implications for variable rate seeding of the corn population response curves estimated by Pioneer Hi-Bred agronomists. Examples are developed for various mixes of low, medium and high yield potential soil, as well as for a range of seed costs and variable rate equipment costs. The strategies analyzed were: variable rate planting using agronomic recommendations for each yield potential zone, variable rate planting using an economic decision rule for each yield potential zone, an information strategy which sets the uniform planting rate at the highest population indicated by agronomic recommendations for any part of the field and a second information strategy which uses an economic decision rule for the whole field based on potential in each yield zone. The economic decision rule sets the value of additional yield produced by adding a few more plants equal to the cost of planting a few extra seeds.  Major assumptions of the analysis include: only corn is considered for variable rate planting, 1000 acres of corn are planted annually, the yield potential zones are small, irregularly shaped and interspersed so that changing population by field is ineffective, the zones are accurately mapped and corn price at harvest is $3/bu. The analysis does not include risk, alternative uses for low yield potential soil or the benefits of variable rate planting other than seed cost savings and matching population to the yield potential of the soil.  The general conclusion is that variable rate seeding has profit potential only for farmers with some low yield potential land(<100 bu./a). Farmers with mix of medium and high potential land are better off with uniform rate seeding. The surprise is that variable rate seeding is potentially profitable when the proportion of low yield land is small. In the example, the farm with 10% low yield potential soil shows positive returns to variable rate planting. The results are not particularly sensitive to seed cost or variable rate investment cost”.  

Author: J. Lowenberg-DeBoer, Universidad de Purdue. Source: Agricultura de Precisión, Manfredi, Córdoba, Argentina.  Consult other works in Spanish of the same institution in:  INDICE AGRARIO: AGRICULTURA DE PRECISION.

 

Nitrogen Management in Corn Using Site-Specific Crop Response Estimates from a Spatial Regression Model (Look this paper in the category: Ensayos a Campo)

Abstract: “Adapting variable rate technology (VRT) to Argentine conditions requires methods that use inexpensive information and that focus on the inputs and variability common to Argentine maize and soybean growing areas. The goal of this study is to determine if spatial regression analysis of yield monitor data can be used to estimate the site-specific crop Nitrogen (N) response needed to fine tune variable rate fertilizer strategies. N has been chosen as the focus of this study because it is the most commonly used fertilizer by corn farmers in Argentina. The methodology uses yield monitor data from on-farm trials to estimate site-specific crop response functions. The design involves a strip trial with a uniform N rate along the strip and a randomized complete block design, with regression estimation of N response curves by landscape position. Spatial autocorrelation and spatial heterogeneity are taken into account using a spatial error model and a groupwise heteroskedasticity model. A partial budget is used to calculate uniform rate and VRT returns. First year data indicate that N response differs significantly by landscape position, and that VRA for N may be modestly profitable on some locations depending on the VRT fee level, compared to a uniform rate of urea of 80kg ha-1. A more complete analysis will pool data over many farms and several years to determine if reliable differences exist in N response by landscape position or other type of management zone. The study is planned for four years. The purpose of this preliminary analysis is to show how spatial regression analysis of yield data could be used to fine tune input use”.

Authors: Rodolfo Bongiovanni (Proyecto Agricultura de Precisión, INTA Manfredi), J. Lowenberg-DeBoer (Departamento de Economía Agrícola - Universidad de Purdue).  Source: Agricultura de Precisión, Manfredi, Córdoba, Argentina.  Consult other works in Spanish of the same institution in:  INDICE AGRARIO: AGRICULTURA DE PRECISION.

 

Precision Agriculture in Argentina – 2001 (Look this paper in the category: Presente y Futuro)

Abstract:  “Argentine farm managers see precision agriculture as a means as a means to reduce costs in grain production, to increase productivity and make input use more efficient. Yield monitors, Global Positioning Systems (GPS) guidance and satellite images are increasingly used in large operations, while variable rate application (VRA) is rare. Factors discouraging precision agriculture adoption are: high investment cost, high risk, low management-induced soil variability, and the widespread use of custom operators. Factors that encourage its adoption include: large farm operations with relatively high capital per worker, highly educated farm management, technology available from abroad, need for yield information, and ease of pooling data. The objective of this article is to present Argentina as a case study in the adoption of precision agriculture”.

Authors: Rodolfo Bongiovanni y James Lowenberg-DeBoer.  Source: Agricultura de Precisión, Manfredi, Córdoba, Argentina.  Consult other works in Spanish of the same institution in:  INDICE AGRARIO: AGRICULTURA DE PRECISION.

 

Precision Agriculture in the 21st Century. Geospatial and Information Technologies in Crop Management

Description: "Sensors, satellite photography, and multispectral imaging are associated with futuristic space and communications science. Increasingly, however, they are considered part of the future of agriculture. The use of advanced technologies for crop production is known as precision agriculture, and its rapid emergence means the potential for revolutionary change throughout the agricultural sector. Precision Agriculture in the 21st Century provides an overview of the specific technologies and practices under the umbrella of precision agriculture, exploring the full implications of their adoption by farmers and agricultural managers. The volume discusses how precision agriculture could dramatically affect decisionmaking in irrigation, crop selection, pest management, environmental issues, and pricing and market conditions. It also examines the geographical dimensions--farm, regional, national--of precision agriculture and looks at how quickly and how widely the agricultural community can be expected to adopt the new information technologies. Precision Agriculture in the 21st Century highlights both the uncertainties and the exciting possibilities of this emerging approach to farming. This book will be important to anyone concerned about the future of agriculture: policymakers, regulators, scientists, farmers, educators, students, and suppliers to the agricultural industry".

Contents: 1. Dimensions of Precision Agriculture. 2. A New Way to Practice Agriculture. 3. Adoption of Precision Agriculture. 4. Public Policy and Precision Agriculture. References. Glossary.

Authors: Steven T. Sonka, Marvin E. Bauer and Edward T. Cherry.  Committee on Assessing Crop Yield: Site-Specific Farming, Information Systems, and Research Opportunities, National Research Council (USA).  1998, 168 pages.

Publisher: National Academy Press.

 

Value of pH Soil Sensor Information (Look this paper in the category: Ensayos a Campo)

Abstract: “The economic trade off between grid soil sampling and laboratory tests, or soil sensor data is the choice between relatively accurate information at a few points, or less accurate information a many points. Estimates indicate that the value of yield lost due to sensor measurement error is small”.

Authors: J. Lowenberg-DeBoer - Alan Hallman (Departamento de Economía Agrícola - Universidad de Purdue).   Source: Agricultura de Precisión, Manfredi, Córdoba, Argentina.  Consult other works in Spanish of the same institution in:  INDICE AGRARIO: AGRICULTURA DE PRECISION.

 

 

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