Preliminary Studies on the Mechanism of Winter Dinoflagellate Bloom in Xiangxi Bay of the Three Gorges Reservoir
In order to investigate the mechanism of the winter dinoflagellate bloom in Xiangxi Bay of the Three Gorges Reservoir, field data of phytoplankton and the corresponding water environmental factors were collected from January to February, 2010, The dinoflagellate bloom was observed at the end of Xiangxi Bay, and Peridiniopsis sp. was identified as the predominant species. The bloom lasted for 44 days, and the maximum cell density reached 11. 8 × 106 L-1. Moderate water temperature, adequate nutrients, sufficient sunlight and weak thermal stratification were identified as the main factors causing the dinoflagellate bloom. The favorable ratio of mixing depth to euphotic depth (Zmix/Zeu) for the growth of dinoflagellates was from 2 to 3. Algal bloom was not observed at the middle and lower reaches of Xiangxi Bay, which was due to the strong vertical mixing. The fading of the dinoflagellate bloom mainly resulted from the development of thermal stratification and the decrease of Zmix/Zeu.
Three Gorges ReservoirXiangxi Baywinter bloomsdinoflagellatesmechanism
NETL
NSTL
万方数据
维普
