本文研究了辽西褐土区特定的生态环境,寻出影响土壤储水量变化的主要生态因子及其变化规律,以水量平衡原理、伊万诺夫蒸散公式为基础,将时间序列理论引进SPAC系统,建立一个适合该地区特点的数学模型.经1987年和1988年土壤储水量对模型检验,结果证明模型可预测该地区干旱年或水分充沛年土壤储水量. This paper studied the specific ecological environment of the cinnamon soil area in western Liaoning and found out the main ecological factors that affect the change of soil water storage capacity and its variation law. Based on the water balance principle and Ivanov’s evapotranspiration formula, the time series theory was introduced into the SPAC system, A mathematical model suitable for the characteristics of the region was established.According to the soil water storage in 1987 and 1988, the model was tested and the results showed that the model could predict the soil water storage during the dry years or the years with plenty of water in the area.