The effect of agricultural waste biochar on the availability of silicon in ultisol and inceptisol under flooded conditions

The research was conducted to know the effect of several kinds of biochar on the availability of Silicon (Si) on different soils in a flooded condition. The experiment used a complete randomized design (CRD) with two factors: biochar and soil type. Biochar type consists of B1 = rice straw; B2 = rice husk; B3 = sawdust; B4 = coconut shell; B5 = corn stover. Soil type consists of T1= Inceptisol and T2 = Ultisol. Each treatment is replicated three times. The experiment used 2 kg of soil, and the dose of biochar was 5 tons.ha−1. Incubation is carried out for four weeks by maintaining a water height of 5 cm. Soil observation parameters include organic carbon, total Si, available Si, water leached Si, and pH H2O. The data were analyzed using Analysis of Variance with 95% and 99% confidence levels, Duncan’s Multiple Range Test, and Correlation Test. The results showed that rice husks biochar has a higher total Si and available Si than other biochar. Rice husk biochar gives the highest available Si of Inceptisol (8.66 mg.kg−1) and Ultisol (7.49 mg.kg−1) compared to the other biochar. Silicon leaching ranges from 5.23-8.66% of soil available Si in both soils.