Effects of filter cake application on soil chemical properties in sugarcane agroecosystems

Resumen

Objective: To evaluate the effects of filter cake application on the chemical properties of a Fluvisol under a sugarcane agroecosystem.

Design/methodology/approach: A targeted soil survey was conducted at a surface depth of 0-30 cm in a Fluvisol cultivated with the sugarcane variety CP 72-2086, in order to identify areas with and without filter cake irregularly distributed at different depths and soil compartments. The soil chemical properties evaluated included pH, electrical conductivity (EC), organic carbon (OC), organic matter (OM), total nitrogen (TN), the C/N ratio, and available phosphorus (P).

Results: The incorporation of filter cake after eight years in a sugarcane-cultivated Fluvisol resulted in statistically significant differences in pH, organic carbon, and organic matter. In addition, filter cake application promoted low to medium levels of available phosphorus, mainly in the rhizosphere and in two filter cake thickness treatments.

Limitations on study/implications: The chemical composition of filter cake varies according to sugar mill processing conditions, clarification reagents, storage practices, and composting procedures, which may lead to variability in the results reported across studies.

Findings/conclusions: The results indicate that filter cake positively influences key soil chemical properties such as pH, organic matter, organic carbon, and available phosphorus, particularly in the rhizosphere, thereby enhancing the long-term sustainability of sugarcane soils.