A SFUDY ON THE SOIL WATER MOVEMENT PATTERN OF A "BI-UTILIZATION PIPE" IN A IRRIGATION AND DRAINAGE SYSTEM

To set up the underground irrigation and drainage system becomes a developing tendency for the countries of the whole world. By using the pipe only for irrigation or drainage will cause greater investment and higher cost which will restrict the popularization of underground irrigation and drainage system. This study suggests to set up one permeable pipe under the ground for both works of irrigation and drainage. That is why authors call such pipe the "bi-utilization pipe" . From the experiments of the soil water movement pattern that shows the "bi-utilization pipe" is able to be used for both irrigation and drainage under the ground.