NEAR-INFRARED SENSING OF MANURE NUTRIENTS

Abstract

The effectiveness of near-infrared (NIR) technology for quickly analyzing the nutrient content of three types ofanimal manure was evaluated. Swine lagoon effluent, liquid swine pit manure, and solid beef feedlot manure were tested.An NIRSystems 6500 scanning monochromator unit was calibrated against wet chemistry data. Total solids (TS), totalKjeldahl nitrogen (TKN), ammonia nitrogen (NH3-N), total phosphorus (P), and potassium (K) were measured.Correlation coefficients (r) ranged from 0.688 to 0.976, Ratios of data range:standard error of prediction (SEP) variedfrom 7.0 to 13.6 for the various chemical constituents and manure sources. Based on the individual ratios we concludethat NIR techniques will allow us to predict TS, TKN, NH3-N, and K in all three manure types. Further work will berequired before P is predictable.