Project Number: 1902-11130-001-05
Project Type: Grant

Start Date: Sep 27, 2007
End Date: Apr 30, 2009

Objective:
Derive predictive regression equations for nutrient analyses that are conducted by different laboratory procedures and instrumentation through analysis of data collected by the North American Proficiency Testing (NAPT) program consisting of 164 soils by 125 analytical methods tested in average of 165 laboratories in North America.

Approach:
Recipient will coordinate the project, organize the data, and conduct statistical analyses of the data using appropriate statistical methods available through existing statistical packages such as SAS. A minimum of five papers will be developed focusing on: (1) soil pH and EC method comparisons; (2) comparison of soil extractable phosphorus methods; (3) comparison of soil extractable potassium; (4) comparison of soil organic matter methods; (5) an evaluation of laboratory industry performance on primary soil analysis methods; and (6) comparison of soil extractable nitrogen methods.