Studies Of Sensitivity Of A Dynamic Model Of Grain Crop Productivity To Soil-hydrophysicalinformation

摘要

The relationship between a target function of a mathematical model of grain crop growth and development-yield-and variations in the soil and hydrophysical information expressed by variations in the soil water-retention function is considered. The function is approximated with a formula based on soil-hydrological constants. The soil profile in the model is represented by a three-layer structure. Each layer has its own agrohydrological characteristics: maximal hygroscopic moisture, wilting moisture, the least moisture capacity, and saturation moisture. The model AGROTOOL, identified from long-term data on field experiment at the Men'kovo experiment station of the Agrophysical Research Institute (the Leningrad region), is used to estimate the influence of variations in these sets on the barley and winter rye yield. It is demonstrated that the yield is most sensitive to variations in the least moisture capacity of the soil and has the least sensitivity to the change in the maximal hygroscopic moisture.