冬季生态浮床对浮游藻类数量及生物多样性的影响

为了考察生态浮床在冬季的运行效果,选择世博园区白莲泾生态浮床工程为研究对象,研究了冬季生态浮床对浮游藻类数量及生物多样性的影响。结果表明,取样期间浮游藻类生物总量逐月增加,且对照区明显高于浮床区;浮床区与对照区浮游藻类的种群结构差异明显,浮床区以硅藻门为主,而对照区以绿藻门为主。并且,小环藻与细微颤藻的优势度指数均有明显的下降。同时,浮床区的Shannon-Wiener多样性指数明显高于对照区。以上结果均证明,虽然在冬季较低温的情况下水生植物新陈代谢缓慢,但生态浮床仍会影响浮游藻类的数量及生物多样性,从而对水质净化起到一定的改善作用。

Influence of ecological floating bed on density and biodiversity of planktonic algae in winter

To study the operation effect of ecological floating bed in winter, floating bed restoration project of Bailianjing River in Expo Sites was selected as objective. Influence of ecological floating bed in winter on density and biodiversity of planktonic algae investigated. The results showed that density of planktonic algae increased every month during the experiment period, and density of planktonic algae in control area was higher than that in floating bed area. Community structure of planktonic algae density between floating bed area and control area were obviously different. Bacillariophyta was the dominant species in the floating bed area, whereas chlorophyta was the dominant species in the control area. Meanwhile, dominant degree of Cyclotella bodanic and Oscillatoria subtillissima both decreased. In addition, Shannon-Wiener diversity index in floating bed area were obviously higher than that in the control area. All of these results indicated that though the temperature was very low in winter and most of the aquatic plants were grown slowly, the ecological floating bed could influence the density and biodiversity of planktonic algae and improve water quality to a certain extent.