Effects of manure application on carbon,nitrogen, and carbohydrate contents of a silt loam and its particle-size fractions

Summary Changes in the organic matter and carbohydrate contents of a silt loam and of its particle-size fractions were examined after 10 years of applying solid cattle manure. Relative to the unmanured soils, bi-annual applications of 40 and 80 Mg ha^-1 manure increased C, N, and total carbohydrate contents of the whole soil and of all the particle-size fractions. The manure application had no effect on the composition of the carbohydrates. However, the organic matter of the soil with the high application rate (80 Mg ha^-1) was enriched in carbohydrates. The distribution of carbohydrates in the particlesize fractions and the ratio (Ga+Ma):(Ar+Xy) indicated that carbohydrates of both plant and microbial origin were increased upon application of manure to the soil.