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土壤pH值和铝饱和度对农作物生长影响的研究,已进行了半个多世纪。但无论是土壤pH或某些潜育性铝对作物毒性的测定,仍然没有取得一致的意见。例如,在酸性土壤中,铝饱和度达到多少标准时,便有可能引起谷物减产。在宾夕法尼亚洲的两种酸性(pH4.7)老成土(Wharton土和Murrill土)中,由试验得知:Wharton土pH值低于5.5,谷物产量明显下降;而Murrill土pH值低于4.9时,产量仍无明显下降的趋势。然而,当铝饱和度超过12％时,两者产量都减少到最高产量的90％。由此可见,在酸性土壤中,为了预测谷物减产的情况,铝饱和度比pH值更为准确、灵敏。
Research on the effect of soil pH and aluminum saturation on crop growth has been carried out for more than half a century. However, no agreement has been reached whether soil pH or the toxicity of some spermicidal aluminum to crops is determined. For example, in acidic soils, how much of the aluminum is up to saturation could lead to reduced grain yields. In two acidic (pH 4.7), aged soils (Wharton and Murrill) in Pennsylvania, it was experimentally shown that the pH of Wharton soil was below 5.5 and the grain yield was significantly reduced; while the Murrill soil pH was below 4.9 , The yield still no obvious decline trend. However, when aluminum saturation exceeds 12%, both yields are reduced to 90% of maximum production. Thus, in acid soils, aluminum saturation is more accurate and sensitive than pH in order to predict grain yield reduction.