Influence of Sugarcane Cropping on the Quality of an Oxisol and an Inceptisol in Mauritius.

Productive capacity of Mauritius soils could be declining with sugarcane monoculture. Effects of short- and long-term sugarcane cropping on quality of an Oxisol and an Inceptisol were assessed to a depth of 50 cm. In the short term (<25 years), cropping led to less organic matter and topsoil microbial biomass (0 to 15 cm), probably through increased microbial breakdown of organic matter (OM) and downward movement by tillage. The pH of both soils and the cation exchange capacity (CEC) of the Oxisol increased following application of lime, fertilizers, and organic amendments. Physical properties were also affected. Aggregate stability decreased and topsoil was compacted, whereas plant-available water and permeability improved. In the long-term (>50 years), OM and microbial biomass increased with inputs of crop residues, whereas exchangeable base levels improved in the Inceptisol with organic amendments. Physical properties did not change much in the long term, even if some improvement was noted in structural and hydraulic properties. [ABSTRACT FROM AUTHOR]