Salt removal effect of gypsum
Gypsum is used as a building material, fertilizer and soil conditioner, but it also has an effect on rehabilitating salt damage (desodification) of the soil in farmlands affected by seawater inflow caused by typhoon, storm surge, tsunami etc.
Salt Salt (sodium chloride) from seawater remains in the soil and affects the growth of crops. While chlorine tends to flow into water, sodium adheres to the surface of soil particles and is said to be difficult to remove with water. Therefore, desodification can be applied by exchanging sodium (ion) adsorbed by the soil from sea water with calcium (ion) from gypsum, and then turning it into an aggregate structure. This process will enable soil recovery.
Mechanism of Desodification ① (replacement of sodium with calcium)
Mechanism of Desodification ② (sodium discharge by aggregation)
To learn about the effect of desodification by applying gypsum, please refer to the guidelines and demonstration examples as follows.
1. Guidelines set by national and local government regarding post-earthquake salt-affected farmlands
Farmland desodification manualMinistry of Agriculture, Forestry and Fisheries (this link will lead to the Ministry of Agriculture, Forestry and Fisheries website)
＜In page 15, gypsum (calcium sulfate) is mentioned as a measure against salt damage＞
Technical information on agricultural crops associated with the 2011 Tohoku Earthquake (1st report)Miyagi Prefectural Government Agricultural Horticultural Environment Division (this link will lead to the Miyagi Prefecture website)
＜Page 4 describes gypsum as desodification material＞
- Farmland desodification manualMinistry of Agriculture, Forestry and Fisheries (this link will lead to the Ministry of Agriculture, Forestry and Fisheries website)
2. Academic validation on desodification effect of gypsum
- Influence of seawater inflow into agricultural land on agricultural crops and its countermeasuresPublished in 2004 by Kagawa Prefectural Government Agricultural Management Division (this link will lead to the Kagawa Prefecture website)
- Practical implementation of alkaline soil improvement and stable food production by desulfurized gypsumMatsumoto and Chun, JSPS Research for the Future Program WG3-24 (this link will lead to Keio Associated Repository of Academic Resources)
3. Demonstration example of gypsum desodification effect in reclaimed land (Links to Scholarly and Academic Information Navigator CiNii)
- Effect of Soil-improving Inputs for the Salts Exclusion from reclaimed land in Kasaoka BayFaculty of Agriculture, Okayama University. Miyake et al., 1988; Scientific reports of the Faculty of Agriculture, Okayama University Vol 72.p77-87
- Soil Layer Change in Experimental Field Resulting from the Drying after Land DrainageFaculty of Agriculture, Okayama University. Uchida et al., 1988; Scientific reports of the Faculty of Agriculture, Okayama University Vol 72.p43-50
Proper desodification material is required depending on the method of countermeasures against salt damage and the condition of the customer's agricultural land.
Please contact the address below for details.
Yoshino Gypsum Co., Ltd. Ceramic Sales Division
3-3-1, Marunochi, Chiyoda-ku, Tokyo, 100-0005, Japan