Alkaline soils are characterized by a high pH level, typically above 7.0, which indicates a lower concentration of hydrogen ions. These soils often contain higher amounts of calcium carbonate and sodium, which can affect nutrient availability for plants. Common in arid and semi-arid regions, alkaline soils can limit the growth of certain crops that prefer more acidic conditions. The presence of alkaline conditions can lead to nutrient deficiencies, particularly of iron and manganese, which are essential for plant health. Farmers may need to amend alkaline soils with organic matter or specific fertilizers to improve soil quality and support crop production.