The Experimental Study On Coupling Effect Mechanism And Model Of Crop Response To Water Of Uun-sufficient Irrigation Under Intercropping Condition

Under he current severe situation that the water resource of Yellow River is in short supply and the amount of water being drawn from Yellow River is shrinking, how to take full advantage of the limited water resource and irrigate more fields without or with little decrease in the output of crops has been a big problem for the dry area and loop irrigation district in the north of the country. This paper takes wheat and crops which are the main grain crops in loop irrigation district in Inner Mongolia as the object of study. An experiment of insufficient irrigation is conducted under different irrigating condition and different planting pattern in Linhe dawn Experiment Station of Bayannaoer City. On the basis of the analysis on the statistics from the experiment, the relevant crop - water model is constructed and the main research production is as follows:1. The influence to physiological index (plant height, leaf area, dry material, photosynthesis speed, nitrogen content, yield and water utilization efficiency) of wheat and crops under different irrigating condition and different planting pattern has been analyzed. The result is that the physiological index under sufficient irrigation is comparatively high except water utilization efficiency. The index decreases as the irrigation reduces, which contributes to the direct reflection of the influence from drought at different growing stages.2. The soil moisture under different treatment varies as the irrigation varies in the growing stages. It reaches the highest with full irrigation. The higher the soil moisture is, the better the crops grow. As the decrease of irrigation, the soil moisture relevantly reduces, which leads to the fall of physiological indices.3. Taking rainfall and the yield reduction from insufficient water into consideration, the connections between crop yield and water amount of whole growing period as well as every growing stage is analyzed and established according to the statistics from the deficit irrigation experiment, based on which sensitive index for common crop - water model is worked out. What's more, Minhas model has been chosen as the proper crop-water model in the experimental area.