Soil Particle‐size Fractions and Nitrogen Mineralization

Summary Fractionation of East African arable soil samples into size groups < 2 mm has significantly influenced mineralizable N values. There was no evidence to suggest that refined soil fractions of < 2 mm would be an advantage for the determination, by incubation methods, of mineralizable N. Differences were more nearly related to simple physical fractionation of the soil. Organic C, total N, and silt contents of the different particle‐size fractions were positively and significantly correlated with mineralizable N; coarse plus fine sand content of the different soil fractions was negatively and significantly correlated with mineralizable N.