Simulating Studies On Water-transport In Plant Stem

The fresh water resource is in a grim situation in our country, especially in the arid area at the West China. It has affected and restricted the development of afforestation and agriculture. Enlightened by water transport in plant, Water-transporting device simulating the root and stem system in plant was made to help plant get water. Being a method of irrigation, the water-transporting device can also help facilitate the development of agriculture and afforestation. Water transport channel was investigated and the mechanism and impetus of water uptake in plant were analyzed in this paper. The main channel of water transport is the vessel in xylem of the stem. The cells, mainly the vacuoles, act as reservoirs in stem. The impetus of water uptake is "transpiration pull"and capillarity phenomena. Simulating the mechanism of water transport, we made water-transporting device using hollow fiber to simulate the vessel, and using the filling materials to simulate the water-storage cell. Water-transporting device was set up by using the gel as the filling material first. The results of experiment prove that water can be taken up by capillarity phenomena of hollow fiber. Considering the difficulty of water transportation to soil when using the gel as the filling material, the method of using sand as the filling material was employed. The effects of hollow fiber on water transport character of water-transporting device are studied so that we can choose the type of hollow fiber, which facilitates the water transport to make the device. It can be prove that the water-transporting device can transport and provide water to plant. In order to get ideal hollow fiber, which facilitates the water transport, polysulfone hollow fiber was prepared in our lab. Water flux measurement and SEM were employed to characterize the structure and morphology of hollow fiber. The applications of water-transporting device are pointed, including providing water to young plants; applying "infiltrating irrigation"in farmland and irrigating potted landscape. Many kinds of applications as well as further research and development are proposed. It is believed that the simulating water-transporting device must have a bright future in agriculture and afforestation for arid areas.