外源草酸和柠檬酸对土壤中磷释放量的影响

摘要

利用化学浸提法，研究了不同浓度外源草酸和柠檬酸的添加对构树和桑树根际土壤磷释放量的影响。结果表明，草酸和柠檬酸浸提液能显著提高两种植物根际土壤的磷释放量，在0～10 mmol／L 外源有机酸浓度范围内，土壤磷释放量与有机酸浓度呈正比关系。在同一植物根际土壤中，利用柠檬酸浸提的根际土壤磷的释放量要高于草酸的浸提量；草酸、柠檬酸对构树根际土壤磷的活化能力要强于对桑树根际土壤磷的活化能力，这可能与构树的环境适应性能力强有关。%This study investigates different exogenous oxalic and citric acids addition on rhizosphere soil phosphorus release of Broussonetia papyrifera and Morus alba by chemical extraction.The results show that both of oxalic acid and citric acid can increase rhizosphere soil phosphorus release of two plant spe-cies significantly.The higher concentration of organic acids,the greater of soil phosphorus release in range 0 ~10 mmol /L of organic acid concentration.The capacity of citric acid to release phosphorus is stronger than that of oxalic acid under the same plant rhizosphere soil;the ability of oxalic acid,citric acid on soil phosphorus ability of B.papyrifera rhizosphere was stronger than that of M.alba.The results may be re-lated to the intensity of environmental adaptability ability of B.papyrifera.