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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Economic Analysis of Dryland Wheat Tillage Practices in Box Elder County, Utah

Bond, Michael Dale 01 May 1992 (has links)
The purpose of this study was to determine the economic viability of various dryland wheat tillage systems, many of which were developed from years of cooperative research efforts. In the study three conventional tillage methods were analyzed along with ten conservation tillage practices. The study farm consisted of 2000 acres, of which 1000 acres are classified as land 1 and its wheat yield is assumed to be 35 bushels per acre for non-continuous tillage methods and 23 bushels per acre for continuous tillage methods. The remaining 1000 acres are classed as land 2 and its assumed wheat yield is 30 bushels per acre for non-continuous tillage methods and 20 bushels per acre for continuous tillage practices. The farm operating conditions were changed to allow for an economic evaluation of questions that a dryland farmer would face. Questions such as: 1. do no-till chemical-fallow treatments have higher profits than do conventional tillage treatments; 2. will it pay for my farming enterprise to participate in the 1990 Farm Bills' Acreage Reduction Program (ARP); 3. what effect will be on returns to land, labor and management of a new 20-ft combine purchase, were analyzed using the Cost and Return Estimator (CARE) computer enterprise budgeting program developed for USDA-Soil Conservation Service (SCS) for each land class totaling 104 CARE budgets. A computer linear programming optimization model was run using LINDO to examine the 104 CARE budgets for an optimal tillage practice. The results are as follows: 1. Under the study assumptions chemical-fallow (no-till) treatments have higher profits than do conventional tillage treatments, if conventional tillage equipment can be adapted to no-till tillage methods. 2. Participation in the government ARP set-aside will offset the higher machinery ownership costs and thus it would pay to participate. 3 . The purchase of a new 20-ft combine or no-till Yielder drill as well as other major purchases could bankrupt a farming enterprise. It should be handled with CARE.
2

Optimal Compost Rates for Organic Crop Production Based on a Decay Series

Endelman, Jeffrey B. 01 May 2009 (has links)
One of the more challenging aspects of organic farming is the development of an appropriate fertility plan, which may include crop rotation, cover crops, and/or soil amendments. When fertility is maintained by applying manure and/or compost, a pressing question is how much should be used. A framework was developed to address this question based on the idea of a decay series, which is a sequence of numbers quantifying the effects of compost on crop yield over a multi-year period. Prior research has focused on decay series expressed in nitrogen fertilizer equivalents. Given this information, I show how to calculate what manure/compost rates are needed to meet the nitrogen targets in a multi-crop rotation. Analogous results are presented for when the objective is profit rather than yield maximization. The planning framework is then generalized to include decay series where the carryover effects of manure/compost are measured, not against nitrogen fertilizer, but against new applications of the amendment. This change of basis, from nitrogen fertilizer equivalents to manure/compost equivalents, allows for field research on organically certified land and quantifies non-nutritive effects in a more meaningful way. Two case studies are presented to illustrate how this new type of decay series may be estimated and used to optimize crop production. By using data from a continuous corn (Zea mays L.) system amended with cattle manure slurry, the case study in estimation explores the methodological challenges that arise when the yield response to nitrogen fertilizer is not available as a benchmark. The case study in optimization looks at profit-maximizing compost rates for dryland, organic wheat (Triticum aestivum L.) in northern Utah.

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