The Law Of Soil Water Movement And Its Influence On Growth Of Crop In Oasis Farmland

In this study, winter wheat and corn were chosen to be research objects. Based on data collected from field experiments, one-dimension soil moisture dynamic model containing root water uptake was applied. The model simulated evapotranspiration, root water uptake and soil water movement of winter wheat in different water stress and of corn in different water and fertilizer conditions. According to the simulated results and measurement data, dynamics of soil moisture, root water uptake, evapotranspiration of crop and its influence on growth of crop were analyzed to provide theory for the prediction of soil water dynamics and the frame of water-saving irrigation system. The major conclusions are as following:1. One-dimension soil moisture dynamic model containing root water uptake was applied to simulate the field soil water movement in oasis of arid region. The model represented preferably the influences of water stress and water and fertilizer coupling on evapotranspiration, root water uptake of winter wheat and corn and the process of water movement of field.2. The simulated results show that the root system of winter wheat take up water mainly from 0~80cm deep. Water stress can facilitate the development of new root of winter wheat that makes root system adequately take up water in mid-down layer soil and then attain the effect of water saving.3. The influence of water stress on the height of winter wheat in jointing stage is more serious, and the dry weight of aboveground and underground matter and yield of winter wheat decrease obviously under water stress in grouting stage. The yield winter wheat suffered from water stress in joint stage and then was re-watered was higher than other stage. So in jointing stage low degree of water stress was accepted, yield will decrease under any degrees of water stress in grouting stage, and the great irrigation must avoid in mature stage for fear the leakage of water leading to the waste of water resource and salinity of soil. 4. The offer form the quantity of watering which is 70% and 85% of soil water receptivity is same. The ability of root water uptake can be enhanced by high fertility at a certainly extent and the absorbing of nutrient can be improved by the high watering quantity, but the optimal treatment is middling fertility and water quantity. 5. Water is the major factor to control the height and the development of leaf and stem of corn require relatively good water conditions while the development of spike requires relatively high fertility. The dry matter weight of leaf and stem with the treatment of low fertility and middling watering, low fertility and high watering while spike with the treatment of high fertility and low watering are more relatively. For the yield of corn, the yield with the treatment of middling fertility and watering is higher than other treatments. Therefore, different fertilization and irrigation system in different development stages are needed to ensure the normal development of corn.