Field Incubation Studies on Nutrient Mineralization of Bagasse on Spodosols and Histosols in Florida

Abstract

The addition of organic byproducts to soils is a vital source of essential nutrients for plant uptake. To reuse the nutrients effectively, there is a need to estimate the release patterns of nutrients from the byproducts. This study aimed to investigate the release patterns of nutrients [nitrogen (N), phosphorus (P), and potassium (K)] from bagasse, a sugarcane milling byproduct, at two soil depths (surface at 0 cm vs. buried at 15 cm) in sugarcane and fallow fields on two soil types (Histosols vs. Spodosols) in Florida. In addition, field incubation studies were conducted using the mesh bag technique for one year of sugarcane production. The nutrient release patterns and bagasse decomposition rates were determined under each scenario. The results indicated that bagasse decomposed faster when buried (totally decomposed after approximately 450 days) than when placed on the soil surface (about 50% remained after 450 days) in both sugarcane and fallow fields on Spodosols and Histosols. Bagasse decomposed faster in Histosols compared to Spodosols. N and P showed net immobilization after approximately one month of bagasse application when buried, which indicated additional N and P fertilizers should be considered to meet crop demand. K presented no immobilization, with a rapid initial release in Spodosols and a gradual release in Histosols.

Keywords

• bagasse
• field incubation
• nutrient release
• sugarcane