Desalinization Effect of Pennisetum Alopecuroides and Characteristics of Leachate Depending on Calcium Chloride (CaCl₂) Concentration

Background and objective: Calcium chloride (CaCl₂) and sodium chloride (NaCl) are commonly used as a deicing agent in South Korea and penetrate the soil on the roadside, causing damage to plants. This study was conducted to investigate the salinity reduction effect of Pennisetum alopecuroides and the chemical characteristics of soil leachate. Methods: The plants were treated with five different concentrations of CaCl₂ (0, 1, 2, 5, and 10g·L⁻¹) and were grouped into the Cont., C1, C2, C5, and C10 groups. CaCl₂ of 200 m·L⁻¹ was sprayed to each plant once every two weeks. The growth of P. alopecuroides (plant height, leaf length, leaf width and the number of leaves) was measured. The level of EC and pH, and exchangeable cations (K⁺, Ca⁺², Na⁺, and Mg⁺²) in the leachate of soil was monitored. Results: The pH of soil leachate decreased as the CaCl2 concentration increased, and the EC increased significantly. The content of K⁺ did not change significantly until the concentration of CaCl₂ reached 5 g·L⁻¹, but the content of Ca²⁺, Na⁺, and Mg²⁺ significantly increased. The plant height, leaf length, and leaf width of P. alopecuroides showed the highest value in CaCl₂ 1 g·L⁻¹ followed by CaCl₂ 2 g·L⁻¹ and the control group. Root fresh weight was the highest in CaCl₂ 2 g·L⁻¹. On the other hand, there was no change in the shoot fresh weight, dry weight and root dry weight, and P. alopecuroides growth inhibition at the concentration of 5 g·L⁻¹ or higher in the plant height and leaf length. Conclusion: P. alopecuroides is relatively highly salt-tolerant and can improve the salt damaged soil by lowering the content of the salt-based exchangeable K⁺ ions.