缺磷条件不同钙浓度水培杉木营养液酸度的比较

为了探讨施用钙肥对增强杉木根系活力以适应缺磷环境的效果，笔者通过设计6个钙浓度室内水培模拟试验，进行缺磷条件不同钙浓度水培杉木营养液酸度的测定比较，分析不同胁迫时期营养液酸度的变化规律。结果表明：水培杉木营养液酸度随缺磷胁迫时间推移，呈先上升后缓慢下降的变化规律。与低钙处理Ⅳ（2.0 mmol/L）、Ⅴ（1.0 mmol/L）、Ⅵ（0 mmol/L）相比，加钙处理Ⅰ（7.0 mmol/L）、Ⅱ（5.0 mmol/L）、Ⅲ（3.0 mmol/L）条件下根系分泌酸性物质数量明显增多，有利于杉木增强根系活力以抵抗缺磷逆境。

Comparison of Acidity in Hydroponic Cultivation for Chinese Fir with Different Calcium Levels under Phosphorus Stress

By determining and comparing of the acidity value in hydroponic cultivation for Cunninghamia lanceolata under phosphorus stress,hydroponics was adopted to study effects of calcium to strengthen on the adaptability of Cunninghamia lanceolata with 6 different calcium levels treatments.The results showed that：the change law was that the acidity increased first but then decreased slowly during phosphorus stress.Compared with the treatments of Ⅳ （2.0 mmol/L）,Ⅴ （1.0 mmol/L） and Ⅵ （0 mmol/L）,quantity of root acid exudation markedly increased in the treatments Ⅰ （7.0 mmol/L）,Ⅱ （5.0 mmol/L） and Ⅲ （3.0 mmol/L） with higher calcium levels,which could strengthen the root vigor of Cunninghamia lanceolata to resist environmental phosphorus stress.