An experimental study on chemical properties and salt exclusion of polder soil: A case in Isahaya bay polder [Japan]

Soil in sea coast reclamation has rich salt. High electric conductivity of the soil could be the largest trouble in crop culture. Therefore it is important for crop product to remove salt from the soil. A purpose of this study is to clear the process which desalinization in sea coast reclamation is progressing. Isahaya bay polder soil was selected as the material in this study. At first, chemical properties of the soil were analyzed. Next, salt exclusion experiment using four wagner pots with the soil and gypsum were carried out. The results were summarized as follows: 1) The soil was judged to be the alkaline soil, because the ESP were 25 to 68 %. 2) The gypsum dressing more than calculated amounts was an effective countermeasure for the salt exclusion. 3) It suggested that the sufficient mix of the soil and the gypsum was important. 4) It was important that the amount of gypsum dressing was determined after consideration of the decrease of CEC with the desalinization