|Reeves Iii, James|
|Van Kessel, Jo Ann|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/28/1999
Publication Date: N/A
Technical Abstract: The objective of this study was to investigate the feasibility of using Near-Infrared Reflectance Spectroscopy (NIRS) to determine constituents of dairy manures related to their value as fertilizer. One hundred and seven diverse dairy manures, collected from dairy farms in the northeastern US were assayed by conventional means and NIRS for C, total N, NH3, moisture, P and K. Samples were scanned from 400 to 2498 nm in polyethylene bags on a NIRSystems Model 6500 scanning monochromator equipped with a sample transport device. Calibrations were developed using a one-out cross validation procedure using Partial Least Squares Regression. Preliminary results showed that 8 samples were outliers due either to inaccurate conventional analysis or for being uncharacteristic (i.e., two samples had moisture contents below 72% while all others were above 78%), and were removed from further consideration. Final calibration results using the remaining 99 samples demonstrated that NIRS can accurately determine the moisture (R2 = 0.945, RMSD = 1.0 %), C (R2 = 0.950, RMSD = 0.40 %), Total N (R2 = 0.956, RMSD = 0.030 %) and NH3 (R2 = 0.967, RMSD = 0.013 %), but not P or K contents of dairy manures. In conclusion, NIRS was shown to be a viable alternative to conventional analysis procedures for determining moisture, C, Total N and NH3 in a very diverse set of dairy manures.