AgEcon Search

AgEcon Search >
       University of Minnesota >
          Department of Applied Economics >
             Staff Papers >

Please use this identifier to cite or link to this item: http://purl.umn.edu/14111

Title: ESTIMATING SITE-SPECIFIC NITROGEN CROP RESPONSE FUNCTIONS: A CONCEPTUAL FRAMEWORK AND GEOSTATISTICAL MODEL
Authors: Malzer, Gary L.
Hurley, Terrance M.
Kilian, Bernard
Authors (Email): Hurley, Terrance M. (thurley@apec.umn.edu)
Issue Date: 2004
Series/Report no.: Staff Paper P04-2
Abstract: Confirming the precision agriculture hypothesis for variable rate nitrogen applications (VRA) is challenging. To confront this challenge, researchers have used increasingly sophisticated statistical models to estimate and compare site-specific crop response functions (SSCRFs). While progress has been made, it has been hampered by the lack of a conceptual framework to guide the development of appropriate statistical models. This paper provides such a framework and demonstrates its utility by developing a heteroscedastic, fixed and random effects, geostatistical model to test if VRA can increase nitrogen returns. The novelty of the model is the inclusion of site, spatial, treatment, and treatment strip heteroscedasticity and correlation. Applied to data collected in 1995 from two corn nitrogen response experiments in South Central Minnesota, results demonstrate the importance of including site, spatial, treatment, and treatment strip effects in the estimation of SSCRFs. Results also indicate a significant potential for VRA to increase nitrogen returns and that these potential returns increase as the area of the management unit decreases. At one location, there was greater than a 95% chance that VRA could have increased profitability if the cost of implementing VRA was less than 14.5 $ ha-1. At the other location, if implementation costs were less than 48.3 $ ha-1, there was greater than a 95% chance of increased profitability.
URI: http://purl.umn.edu/14111
Institution/Association: University of Minnesota>Department of Applied Economics>Staff Papers
Total Pages: 32
Language: English
Collections:Staff Papers

Files in This Item:

File SizeFormat
p04-02.pdf271KbPDFView/Open
Recommend this item

All items in AgEcon Search are protected by copyright.

 

 

Brought to you by the University of Minnesota Department of Applied Economics and the University of Minnesota Libraries with cooperation from the Agricultural and Applied Economics Association.

All papers are in Acrobat (.pdf) format. Get Adobe Reader

Contact Us

Powered by: