Soil Science Society of America Journal · 1981 · 275 citations · 0 references
AgricultureAgronomySoil SciencesElemental AnalysisSoil ChemistrySoil Organic MatterManure Nutrient ManagementNitrogen BalanceNitrogen CycleNitrogen CyclingNitrogen ManagementSoil Nitrogen ChemistryDigestionManure Nitrogen ManagementManure Nutrient AvailabilityMultiple CorrelationNitrogen Dynamics In ManureNitrogen Losses From ManureNitrogen Mineralization KineticsNitrogen To Phosphorus Ratios
Abstract Simple and multiple correlations between available N estimated from a 10‐month greenhouse trial with 10 manures and a number of potential laboratory indexes to available N are presented. The best single chemical index to available N was the N extracted by digestion with pepsin. Slightly more than 80% of the variation in available N was related to variations in pepsin N. High correlations were found between available N and the C released as CO 2 during incubations of 1, 2, and 4 weeks. In a multiple correlation using all chemical indexes plus N and C released in 1‐week incubations, the significant indexes were N released by incubation, C released during incubation and the C/N ratio. In a multiple correlation with all indexes, the significant factors were N released in 1‐ and 10‐week incubations, the C/N ratio, and N released to acid KMnO 4 solution. Pepsin digestion and C release during a short period of incubation appear to be useful single indexes.