Now, there are 17.8 millions rai or about 28.5 thousand square kilometers of northeast saline soil and the yield of crops is extremely decreased. According to the government's policy, Land Development Department tries to develop such land and make it better for planting.

      Mr.Sima Morakul, the Director General of Land Development Department, revealed that the Department had simple methods to solve saline soil problem and the farmers could do it themselves. Such methods are as the following :

To prevent saline soil spread

      1. To avoid building the reservoir in saline groundwater area, otherwise the saline groundwater degree will be as high as the soil surface.
      2. To plant perennials which can grow in saline soil and be suitable for area condition. They will absorb the rain-water and prevent leaching of soluble salt by the rainfall.
      3. In the salt farm, dig a ditch for saline water drainage or build a dike to dam water.

Saline Soil Area Improvement and Usage

      1. There are two methods of using water to leach salts from saline soil.
      - Leaching salts with water (long period) This method is for sandy soil and shallow groundwater. Start flooding soil surface (10 cm. height) all the time to replace drained and evaporate water. This method is suitable for water-resistant crop like rice. It takes less time to solve saline soil problem but wastes a lot of water
      - Leaching salts with water (short period) This method is for deep groundwater and clay. First,

200 cubic meters of water per rai or 1600 sqr.meters is used to melt salts. Then, 300 cubic meters of water per rai or 2400 sqr.meters is used to leach salts from saline soil and prevent salt occurence on top soil. This method is suitable for vegetable and farming crops. It takes more time but less water.
      2. Growing crops in saline soil area.

Farmers can screen salt tolerant crops themselves for growing in saline soil area. They can grow some crops like tomato, garlic, watermelon, luffa, asparagus, lettuce, cowpea, celery, pepper, acacia and cauliflower in medium saline soil.

      In saline soil area, it can grow crops in lower land. The upper land is left for moisture absorption and salt gathering.

      For northeast saline soil, farmers have to flood the farm in order to leach salts until the water become pale brown and drain it. Do like this 2-3 times and add organic fertilizer such as compost, animal manure or grow plants like S. Speciosa and Sesbania rostrata to make green manure.

      For more information, please contact Saline Soil Improvement Subdivision, Soil and Water Conservation Division, Land and Development Department.
E-mail Address : scd_7@ldd.go.th