文摘
To evaluate the importance of dispersal by water transportation in structuring phytoplankton community, we compared phytoplankton composition and succession between two connected tropical reservoirs: a large reservoir with a bottom outlet that periodically feeds a small reservoir via a 40 km open channel. Multivariate analysis was carried out on datasets of phytoplankton for exploring the relationship between phytoplankton and environmental variables. Differential survival of phytoplankton taxa during long channel transportation contributed to high dissimilarity of phytoplankton community between the two reservoirs. Local ecological filtering was mainly responsible for structuring the phytoplankton community with a few dominant functional groups in the large reservoir. Phytoplankton community succession in the large reservoir also showed a clear seasonal pattern. The community in the small reservoir had a more diverse functional group composition and did not show a clear seasonal succession because of strong hydrodynamic disturbance and phytoplankton inoculation with periodic water transportation. In conclusion, periodical transportation and mass effect by dispersal disturb succession and seasonal dynamics, and phytoplankton community assemblage depends on both environmental filtering (habitat selection) and dispersal in the small (receiving) reservoir. In addition, the dissimilarity of phytoplankton community between the connected waters was caused by both habitat difference and differential survival of phytoplankton taxa during transportation. Keywords Succession Dissimilarity Dispersal Environmental filter Water transportation