Abstract: The relationship between phytoplankton succession and dinoflagellate red tide is discussed in this paper. Aseries of marine enclosed experiments in different seasons and years show that in an ecosystem of relatively stable water body enriched with nutrients, a dinoflagellate red tide always appeares following the diatom bloom or its red tide in phytoplankton succession. The abnormal increase of vitamin B₁₂ may promote the succession processes. The succession in stable water column could be interfered by stirring. Under this condition, the diatom bloom would develop continuously. block the formation of dinoflagellate dominance and prevent its red tide formation. The experimental results have practical meaning as they may be used to predict possible dinoflagellate red tide occurrence in enclosed or semi-enclosed waters.

Key words: Red tide, Dinoflagellate, Enclosed ecosystem, Phytoplankton succession, Xiaoxing’anling Mountains, climate change, Pinus koraiensis, radial growth, drought stress