The Use of the Ash from the Burning of Sugarcane Bagasse is Associated with Biosolid Application for Soil Fertility

The incorporation of agroindustrial wastes in the soil is an alternative practice for an adequate environmental destination, and it is a nutrient source. Purpose: This study evaluated the effects of incorporating biosolids associated with sugarcane ashes and their effect on bean crop production in a protected environment concerning nutritional chemical parameters. Methods: The experimental design was in randomised blocks in a 2x4+1 factorial scheme with four replications. The main factors consisted of two doses of ash (5 and 10 t ha-1) and four doses of biosolid (0, 2.5, 5 and 10 t ha-1) in two phenological stages, vegetative (V4) and reproductive (R7). Results: The results showed that adding both waste in the soil provided a better availability of secondary macronutrients and essential micronutrients for the bean crop but lower primary macronutrients. This way, the applied ash doses change the pH, considering its neutralising properties. Adding 10 t of SBA significantly reduced the pH compared to applying 5 t in the absence of biosolid. The soil organic matter content increased with the SBA application, mainly at the dose of 10 t ha-1 of the waste. Combining BS with the highest SBA dose ash (10 t ha -1) generally resulted in elevated P levels. About K contents, the 10 t SBA dose promoted the most significant increase in the content of this element. Conclusion: Regarding the effect of doses, considering the studied phenological stages (V4 and R7), the results were promising even at lower doses of applied waste. This result indicates a dose dependence to complement the crop's nutritional needs.