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作 者 ：姚其华1;刘武定2;陈明亮2;谢振翅1

期 刊 ：植物营养与肥料学报 1999年 5卷 3期 页码：263-272

关键词：机理模型验证；幼苗磷吸收；玉米与大豆；

Keywords:Verification of Mechanistic Models, P uptake by Seedlings, Maize and Soybean,

摘 要 ：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pH值。土壤养分与水分胁迫、土壤质地粘重、土壤施 NH₄⁺-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。

Abstract:By comparing the measured and model calculated P absorbed by seedlings, this paper dealt with the predicting ability and its influencing factors of selected mechanistic models of nutrient uptake by both maize and soybean seedlings. The results showed that: (a) All of the three kinds of selected models can reflect the changing trend of P uptake by seedlings of maize and soybean; (b) Among the three selected models, the predicting ability of SC Model is the poorest and that of C2 Model including the effect of root hairs is the strongest; (c) The important factors influencing models‘ predicting ability are soil nutrient and water levels, soil N forms supplied soil properties and soil Ca levels or pH value; (d) The soil conditions that with P and water stress, clay texture, applied NH₄⁺-N and applied limestone in acid soil can make it become poor for the mechanistic model based on numeric solution to predict P uptake, and this is because that the above soil conditions can induce or strengthen the other actively adaptive mechanism of seedlings‘ root system to intake P which has no been considered in the models.

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