A study was done to assess the chemical properties of a type of soil called Vertisol in a long-term fertilizer experiment with soybean and wheat crops. Different treatments were applied to the crops, including varying levels of nutrients and organic matter. The researchers found that the pH and electrical conductivity of the soil did not change significantly with the treatments. However, the organic carbon content, cation exchange capacity, and calcium carbonate levels in the soil were significantly affected by the long-term application of balanced nutrients with or without organic matter.