The researchers studied how treating phosphate rock with acid can make more phosphorus available in Bihar's alluvial soils. They found that using 50% sulfuric acid was the best treatment, leading to the highest levels of available phosphorus in the soil. The acid treatment increased the water-soluble and citrate-soluble phosphorus fractions, with the most significant effects seen at 50% and 80% acidulation. The study also showed that the acidulated phosphate rock released phosphorus more effectively than inorganic phosphate sources.