Dolomite powder is applied in some agricultural lands. The purpose of applying it is to

Dolomite powder, a mineral composed of calcium magnesium carbonate [CaMg(CO3)2], is primarily used in agriculture as a liming material to correct soil acidity. In many agricultural lands, soil becomes acidic due to leaching or intensive farming, which negatively impacts nutrient availability [1]. Applying dolomite powder increases the soil pH, making it more alkaline or neutral. This process, known as liming, works because the carbonate ions in dolomite react with and neutralize hydrogen ions in the soil. Beyond pH adjustment, dolomite provides essential plant nutrients like calcium and magnesium, which improve soil structure and fertility. While it can indirectly enhance the availability of other nutrients by optimizing the pH environment, its direct and primary chemical purpose in soil amendment is to raise the pH level to a range suitable for crop growth.

Sources

1. [1] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 25: Agriculture > Podzoliziition: > p. 368