太湖冬季底泥中活体藻类的检测

Examination of Alive Algal Cells in the Sediments in Meiliang Bay of Taihu Lake during Winter Period

2002年冬从太湖梅梁湾采集柱状底泥,取三段进行直接镜检和用MA培养基进行光照培养. 镜检发现表层(0-3cm)底泥中有多种藻类细胞,中层(10-13cm)底泥的藻类细胞种类明显减少,下层(20-23cm)底泥中没有发现藻类细胞. 底泥培养的结果与之有相似的趋势,但得到的活体藻类细胞的种类相应减少. 培养3个月后得到在外观和群落结构上与夏季水华相似的群落. 结果表明底泥中的微囊藻和小环藻在太湖底泥中具有良好的适应性,占有明显的优势地位,底泥可以作为水华蓝藻的越冬场所和来年水华的种源.

Three layers of a sediment core collected from Meiliang bay of Taihu Lake in December of 2002, were examined under microscope to identify algae species composition and cultured axenically in MA medium to find the living cells and its vertical distribution in sediment. Many species of algae were found in the surface of the core sample(0-3cm) and three of them (Microcystis aeruginosa Kutz, Cyclotella bodanica Eul, Scenedesmus obliquus(Turp) Kutz) were able to develop in culture 8 them. Less algae species could be found in the layer (10-13cm) of the core sample and only two of them(Microcystis aeruginosa Kutz, Cyclotella bodanica Eul) were developed in culure. Two algae species could be identified in the layer(20-23cm) of the core sample and no algae cell could be developed in culture. It showed that Microcystis aeruginosa Kutz, and Cyclotella bodanica Eul, the dominant phytoplankton populations in summer bloom, could be survive the environment of the sediment in Taihu Lake during the winter period.