| 摘要 |
PROBLEM TO BE SOLVED: To prevent the temperature drop of soil in a greenhouse caused by reduction in soil temperature and to check excessive water to soil in the greenhouse. SOLUTION: A water-permeable block 6 is bonded to one side of a water- impermeable heat insulating material 5. The lower parts of the insulating material 5 and the water permeable block 6 are inserted into a drain conduit 4 long in one direction. The drain conduit 4, the heat insulating material 5 and the water-permeable block 6 embedded in soil on which a house for a greenhouse is built so as to be laid along the side walls of the house to intercept soil outside the house 2 from soil in the zone of the house 2. |
