The Study On Effects Of Regulated Deficit Irrigation Of Paddy Rice In The Phaeozem

The area of northeast China had a lot of phaeozem resource, and it was the important production base of the foodstuff. Paddy rice was the most important variety of foodstuff, the area of paddy rice was becoming lager and larger. Because the lacking water resources was the primary factor for agriculture developing, researching saving mechanism was greatly beneficial to both rationally using the water resources and increasing the foodstuff yield in phaeozem area.According to the field experiment made in Qingan County, Heilongjiang Province from 2008 to 2009, researched the yield and the water consumption of the paddy rice in phaeozem region. This article adopted the field-testing research technique and the room– analyzing methods. It used uniform design U6(66), through controling water quantity to devise the different disposal. The experiment used pressure instrument through taking soil bake to measure soil water characteristic curve. Through the biology character (plant height, leaf area index, root, effective tillers) and the yield, analyzing the different water disposal for these factors influences and determining the lower water limit of different stages. Depended on consumed water quantity and the yield of the different irrigated, used Jensen model, Blank model, Singh model, Stewart model to calculate the Paddy rice- water Production Functions in the phaeozem area of Qingan County, and tested and analyzed the results. Adopted the calculated software of the LINGO of the non-linear programming model to accomplish optimum distribution of limited water during the different growth stages of the crop.The result indicated following content. The soil moisture was important for growth of paddy rice. Under different water disposal, the variational trend of the plant height and leaf area index was similar under the different water disposals. But the biology character(plant height, leaf area index ,dry matter)of the high water disposal was better then that of the low water disposal. Under the deficit irrigation, plant height and leaf area index of disposal 2 and disposal 3 were batter than the other disposal. And these soil moisture was favor of forming reasonable group. The quantity of tillers was growing in pace with addition of soil moisture,disposal 7 was the most, but effective tillers would be reduce. The yield of disposal 2 exceeded the other disposal, and the water use efficiency of the disposal 1 had finer effect comparing with the comparison of the other disposal. It can clearly be seen that deficit irrigation of paddy rice can increase the yield and water use efficiency.Through checking and analyzing the models, Jensen model excelled other models for calculating the different phases of water sensitive index. According to the water sensitive index, in the condition of gaining the same yield, the method could save the water quantity, which was used the calculated software of the LINGO of the non-linear programming model to accomplish optimum distribution of limited water during the different growth stages of the crop. That is using little irrigation quota to gain more yield.Under the condition of the lacked water resource, the restricted agricultural irrigation water and the increaser foodstuff requirement, researched the relation between the crop requirement water and the yield, accomplished optimum distribution of limited water during the different growth stages of the crop, and actualized accurately irrigation had important significance and provided powerful guarantee for the saving water and the high yield.