Answer: Potash
Notes: Alluvium is a loose clay, silt, sand, soil or gravel which is deposited by the running water. Alluvial soils are rich in Potash but deficient in Nitrogen, Humus, Phosphorus. Potash is predominant in Alluvial soil found in Bihar. Potash includes various mined and manufactured salts that contain potassium in water-soluble form. Potash supports plant growth, increases crop yield & disease resistance and enhances water preservation.
