Grazing on toxic and non-toxic Microcystis aeruginosa PCC7820 by Unio douglasiae and Corbicula fluminea |
| |
Authors: | Ying Liu Ping Xie Xiao-Ping Wu |
| |
Institution: | (1) Donghu Lake Ecosystem Experimental Station, Institute of Hydrobiology, Chinese Academy of Sciences, 430072 Wuhan, Hubei, People’s Republic of China;(2) College of Life Science, Nanchang University, 330047 Nanchang, Jiangxi, People’s Republic of China |
| |
Abstract: | To explore the potential grazing effects of mussels on Microcystis aeruginosa, a common bloom-forming phytoplankton, Unio douglasiae and Corbicula fluminea were fed with Scenedesmus obliquus, toxic and non-toxic strains of Microcystis aeruginosa as single food and as mixtures in the laboratory. When fed with single foods, U. douglasiae has similar clearance rates on the three algae populations, while C. fluminea has significantly lower clearance rate on toxic M. aeruginosa than those on the other two algae populations. When fed with mixture foods, both the mussels show significantly higher clearance
rates than on single foods. The clearance rates of U. douglasiae on the different food mixtures are not significantly different, and C. fluminea has a significantly lower clearance rate on the toxic food mixtures than that on non-toxic food mixtures. Although the relative
lower clearance rates of C. fluminea on toxic food, we may still deduce that both the mussels can exert grazing pressure on phytoplankton. The deduction is supported
by the composition of the excretion products. The excretion products (faeces and pseudofaeces) of both mussels contained mainly
S. obliquus. In both mixed-food treatments, the ratios of S. obliquus to M. aeruginosa in the excrete products are significantly higher than those in the foods. Therefore, it can be concluded that both mussels
prefer M. aeruginosa to S. obliquus, and can cause grazing pressure on M. aeruginosa. |
| |
Keywords: | Microcystis aeruginosa PCC7820 Scenedesmus obliquus Unio douglasiae Corbicula fluminea Excrete products |
本文献已被 SpringerLink 等数据库收录! |
|