Final answer:
The release of CO₂ into the soil contributes to the formation of hydrogen ions and carbonate ions, which plays a significant role in the dissolution of calcium carbonate in environments like limestone caves.
Step-by-step explanation:
The release of CO₂ into the soil results in the formation of hydrogen ions (H⁺) and carbonate ions (CO₃²⁻). This occurs as CO₂ reacts with water to form carbonic acid (H₂CO₃), which then dissociates into hydrogen ions and bicarbonate ions (HCO₃⁻). The bicarbonate can further dissociate to form carbonate ions (CO₃²⁻). For example, in limestone regions, this reaction enables calcium carbonate (CaCO₃) to dissolve, and the process can eventually lead to the formation of features such as stalactites and stalagmites in caves.