Effect of Lime on Different Forms of Soil Acidity and Phosphorus Availability in Acid Soil

The incubation study was carried out in the summer of 2023 to investigate the impact of lime on various forms of soil acidity and phosphorus availability in acid soils. at Faculty of Agricultural Sciences, Siksha ‘O’ Anusandhan, Bhubaneswar Odisha. Red and laterite soil that were taken from the experimental field were used in two incubation investigations lab. Four amounts of lime were administered to both soils, along with two levels of phosphorus (P₀-P control & P₁-P @ 40kg/ha (0.066g/pot). In red soil the levels of lime were L₁-0.1 LR (0.2g/pot), L₂-0.2 LR (0.4g/pot), L₃-0.5 LR (1.0g/pot), In laterite soil the levels of lime were: L₁-0.1 LR (0.1 g/pot), L₂-0.2 LR (0.2g/pot), L₃-0.5 LR (0.5g/pot)]. The pH of the soil increased as the lime used increased, but it decreased as the incubation times increased. After a week of incubation, the highest was P₁L₃, where 40 kg of P₂O₅ per hectare was treated in conjunction with lime application at 0.5LR. P₀L₃ showed the lowest value, with lime treatment at 0.5LR without phosphorus (6.66). Depending on the incubation period, applying varying amounts of phosphorus and lime gradually lowers the exchangeable H⁺. After seven days of incubation, exchangeable H⁺ in laterite soil ranged from 0.04 to 0.12 meq/100g. Following six weeks of incubation, ranged between 0.12 and 0.14 meq/100g and grew steadily. The red soil exchangeable Al³⁺ contents were considerably reduced when lime and P treatment rates increased, as well as by the combined impacts of the two applications. Following a 6-week incubation period, exchangeable H⁺ + Al³⁺ in red soil decreased, while the addition of varying phosphorus and lime levels resulted in an increase in exchangeable H⁺ + Al³⁺ in laterite soil. Following the addition of varying quantities of phosphorus and lime to red soil and laterite soil, range of organic carbon was 1.03 to 1.81 % and 0.25 to 0.67% respectively. The rate of lime was when increased in both red and laterite soil, the change in available P gradually reduced. The amount of accessible calcium and magnesium also increased during 42-day incubation period.