微生物对太湖沉积物总磷分布影响研究

利用柱状采泥器采集太湖沉积物,在室内通过辐照灭菌研究微生物对柱状沉积物总磷分布的影响.沉积物混匀装柱后经辐照、添加可溶性淀粉等处理后放置一段时间,分析结果表明:辐照柱状沉积物的pH值比未辐照的柱状沉积物pH值高,说明沉积物中的微生物活动会影响沉积物的pH值;4个柱状沉积物氧化还原电位值的变化十分相似,7～30 cm的沉积物均处于较强的还原状态,在沉积环境下微生物活性对氧化还原电位的影响较小,决定氧化还原状态的主要因素可能是沉积物的压实作用;4个混匀柱状沉积物经处理放置一段时间后均在表层出现磷的聚集,而4～10 cm的总磷含量却低于平均值,这种变化表明在柱状沉积物表层出现了磷素的迁移.

The Influence of Microorganisms on the Total Phosphorus of Sediments from Lake Taihu

In this work,Sediments have been sampled from Lake Taihu;then them were mixed and kept in the PMMA tubes.The mixed sediments were radiated or added with soluble starch to investigate the effect of microbial activity on the total phosphorus of the sediments.The results showed that pH of the irradiated sediment core is higher than the unsterilized one,and microorganisms could have an effect on the pH of sediments.All the four sediments are in the strong reductive environment at the depth of 7～30 cm,and the values of Eh are quite closer,the main factor that affect the redox environment may be the compaction of the sediment.All the sediments had a cumulation of phosphorus at the surface layer,and the total phosphorus of the sediments at the depth of 4～10 cm are lower than the average.It is indicated that phosphorus had been redistributed at the suface layer.