喷灌均匀系数对作物产量影响的模拟研究

Simulating the Effects of Sprinkler Uniformity on Crop Yield

在假定喷灌水量符合线性分布的条件下，提出了一种研究作物产量与灌水均匀系数关系的模型。模拟结果表明，对一定的灌水量来说，作物产量随均匀系数的增大而增加。以净效益最大为原则，用所提出的模型研究了不同灌水均匀系数时的最优灌水量。结果指出，最优灌水量随均匀系数的增大而减小，但随产品价格与水的造价比值的增大而增大。该模型还用来确定不同灌水量时的最优灌水均匀系数，结果表明，最优灌水均匀系数随灌水量的增大而增大，但当毛灌水量与要求灌水量之比超过０．８５时。

A model about the affects of the irrigation amount and uniformity to the crop yield was developed in this study by assuming that the sprinkled water was linearly distributed. The simulation results demonstrated that crop yield increased with increasing irrigation uniformity for a given irrigation amount. The model was used to determine optimum irrigation amount for obtaining maximum net return. The results showed that the optimum irrigation amount depends upon irrigation uniformity and economic factors, decreasing with the uniformity but increasing with the ratio of product price to water cost. The model was also used to determine optimum irrigation uniformity for various irrigation amounts. The optimum uniformity increases with an increase of irrigation amount expressed by a ratio between gross and required irrigation quantity, but approximates 90 % when the ratio exceeds 0.85.