Aggregate characteristics and aggregate-associated soil organic carbon and carbohydrates of soils under contrasting tree land use

Abstract

Protection of soil organic carbon and acid-hydrolyzable carbohydrates in aggregate-size fractions is important for appraising soil degradation and aggregation under land use types. Aggregate-associated soil organic carbon (SOC) and acid-hydrolyzable carbohydrates (R-CHO) in bulk soils and aggregate-size fractions of a sandy loam soil under Alchornea bush, Rubber, Oil palm and Teak plantations in southern Nigeria were studied. Results revealed significant differences in aggregate-associated SOC and R-CHO, bulk densities, total porosity, soil organic carbon stock and aggregate stability among the land use types. Greater SOC was stored in macro-aggregates >0.25 mm, while greater R-CHO was occluded in micro-aggregates 5 µm, therefore they have greater potentials to boost protection of SOC in soil macro-aggregates.

Keywords

• clay content
• organic matter fraction
• plant cover
• soil structure
• water-stable aggregates