莱茵衣藻增殖沉降与死亡过程对太湖底泥氮素释放的影响

以太湖梅梁湾为研究原型区域,采集水样和泥样,通过室内模拟实验,添加莱茵衣藻（ChlamydomonasReinhardtii）于水-泥体系中,研究了莱茵衣藻增殖、沉降与死亡过程对底泥氮素释放的影响。结果表明,莱茵衣藻在大量增殖过程中伴随着藻体沉降,沉降过程中大部分藻体死亡,小部分藻体聚集在底泥表面,当养分增加时其再次增殖并悬浮;藻体增殖、沉降与死亡过程促进了底泥NH4＋-N的释放;上覆水NH4＋-N累积消耗量与底泥脲酶活性呈显著正相关关系。

Effects of Chlamydomonas Reinhardtii Proliferating,Blooming and Decaying on Nitrogen Release from Sediment of Lake Taihu,China

Nutrient releases from sediment in shallow freshwater lakes are partly responsible for eutrophication.Previous studies focused mainly on the release of internal phosphorus,but few of them attempted to define the effects of nitrogen.In the meantime,effects of nutrient release on algae blooming have been widely reported,however,there has been no detailed data available concerning the effects of algae behavior on nutrient releases.Water and sediment samples from Meiliang Bay in Lake Taihu,Eastern China,were employed to investigate the effects of Chlamydomonas Reinhardtii proliferating,blooming and decaying on nitrogen release from sediment under incubation conditions.Algae sedimentation was found during their proliferating and suspending.Most of algae died and decayed during the sedimentation,and minority of them survived on the surface of sediment.Their re-suspending was observed with nutrient increase.In addition,the release of NH4＋-N from sediment was enhanced during the algae proliferating,blooming and decaying.A significant positive correlation between the urease activities of sediment and the accumulated consumption of NH4＋-N in water was found.