Total organic carbon, aluminium and iron in bulk samples and aggregate size fractions of a sandy clay loam humic soil under sugarcane relative to native forest in northern KwaZulu-Natal, South Africa.

The distribution of total aluminium (Al) and iron (Fe) and organic carbon (TOC) in aggregate fractions gives an insight into the dynamics of these elements in soil. This study determined the effects of over 30 years of sugarcane cultivation, compared to adjacent native forest, on Al, Fe and TOC in bulk soil and aggregate fractions within the 100 cm depth of a sandy clay loam humic soil. Samples were separated into large macro-aggregates: LM (>2000 μm), small macro-aggregates: SM (250-2000 μm), micro-aggregates: M (250-63 μm) and silt + clay: SC (<63 μm) fractions.