三江平原小叶章湿地土壤有机硫矿化特征研究

利用开放系统培养法,分别在不同温度和水分条件下,研究了三江平原小叶章典型草甸和小叶章沼泽化草甸两种湿地类型的不同层土壤有机硫的矿化特征。结果表明,在不同培养条件下,两种小叶章湿地土壤有机硫的矿化具有一致性:每层土壤有机硫累积矿化量随培养时间的延长而增加,二者之间符合一级动力学方程。上层土壤有机硫的矿化量高于下层土壤,好气培养条件下每层土壤有机硫的累积矿化量均高于淹水条件下矿化量;30℃培养条件下每层土壤有机硫的累积矿化量均高于20℃培养条件下矿化量。温度、水分条件和土壤类型对土壤有机硫的矿化影响显著,但它们之间的交互作用影响不明显。对比两种湿地类型不同层土壤有机硫的矿化,发现在不同培养条件下,小叶章沼泽化草甸土壤有机硫的矿化速率和潜力均高于小叶章典型草甸。

Study on Mineralization Characteristics of Soil Organic Sulfur in Deyeuxia angustifolia Wetland of Sanjiang Plain

With the open incubation method,the mineralization characteristics of organic sulfur in the soil from the typical meadow and marsh meadow of Deyeuxia angustifolia in Sanjiang Plain were studied under different temperature and water conditions.The results showed that the mineralization of organic sulfur in the soil of the two Deyeuxia angustifolia wetlands were accordant under the different incubation conditions: the cumulative amount of mineralized organic S in every layer increased with the time going on and followed the first-order kinetic equation.The mineralization amount of organic sulfur in the topsoil was higher than that in the subsoil.The mineralization amount of organic sulfur in soil under the aerobic condition was higher than that under the waterlogged condition.The cumulative amount of mineralized organic sulfur in every layer at 30℃ was higher than that at 20℃.Temperature,water condition and soil type all had significant effects on the mineralization of organic sulfur in soil of the two type wetlands,while their interaction was not significant.The comparison results indicated that the mineralization rate and potential of organic sulfur in the soil of Deyeuxia angustifolia marsh meadow were both higher than those in the typical meadow of Deyeuxia angustifolia.