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本文通过不同土壤条件下幼稚苗磷吸收实测值与机理模型预测值的比较，检验了几种养分吸收机理模型对玉米与大豆幼苗磷吸收的预测能力，同时探讨了影响几种养分吸收机理模型预测能力的主要因素。研究结果表明：供试四种机理模型均能较好地反映玉米与大豆幼苗的磷吸收变化情况；四种机理模型中，以建立于解析解基础上的 Ｓ Ｃ 模型的预测能力最低，两种数值解模型的预测能力相当，而以考虑了根毛作用的 Ｃ２ 模型的预测能力最强；影响机理模型预测能力的重要因素是土壤供磷与含水量水平、土壤供 Ｎ 形态、土壤性质及土壤供 Ｃａ 水平或ｐ Ｈ 值。土壤养分与水分胁迫、土壤质地粘重、土壤施 Ｎ Ｈ＋４ Ｎ 及酸性土壤施用石灰等条件均会使数值解机理模型的磷吸收预测能力降低，其原因可归结于这几种土壤条件均能诱导或加强幼苗根系吸收磷的某种主动适应机制，而这种机制并未考虑在养分吸收机理模型之中。
In this paper, the predictive value of phosphorus uptake by immature seedlings under different soil conditions was compared with that predicted by the mechanism model, and the predictive ability of several models of nutrient uptake on phosphorus uptake by maize and soybean seedlings was tested. At the same time, the effects of several nutrient uptake models The main factor of ability. The results showed that all the four models could reflect the changes of phosphorus uptake of maize and soybean seedlings. Among the four models, the S C model based on analytical solutions had the lowest predictive power and the two models The numerical model has the same prediction ability and the C2 model considering the root hair has the strongest predictive ability. The important factors influencing the predictive ability of the model are soil phosphorus supply and water content, soil N supply, soil properties and soil supply Ca level or p H value. Soil nutrients and water stress, soil texture stickiness, soil N +4 N and acid soil application of lime and other conditions will reduce the numerical solution mechanism of phosphorus uptake prediction ability, the reason can be attributed to these types of soil conditions can Inducing or enhancing some active adaptation mechanism of seedlings to absorb phosphorus, and this mechanism is not considered in the model of nutrient absorption mechanism.