Nippon Suisan Gakkaishi 65 (4), 665-672 (1999)

Relationship between the Bloom of Chattonella antiqua (Hada) Ono and the Water Quality or Meteorological Factors

Chitari Ono,*1,*2 Sadaaki Yoshimatsu,*1 and Yoichi Yoshida*3

The relationship between the bloom of Chattonella antiqua and water quality or meteorological factors was examined in the southwest part of Harima-nada, by referring to the Meteorological Agency's data (1986-1988).

In early August 1986, C. antiqua with comparatively high density of cells occurred in the water with low DIN (dissolved inorganic nitrogen), DIP (dissolved inorganic phosphorus), and DIN×DIP, and high DON (dissolved organic nitrogen): DIN, DOP (dissolved organic phosphorus): DIP, TN (total nitrogen): DIN, and TP (total phosphorus): DIP ratios. Then, high density plankton which formed a red tide occurred in the water with low DIN, DIP, and DIN×DIP, and a high DIN:DIP ratio. This occurred in early August 1987 when the meteorological conditions showed high precipitation and low air temperature in mid July, and long sunshine duration and high air temperature in late July.

These characteristics of water quality and meteorological factors suggest that the abnormal occurrence of C. antiqua was closely related to a sudden increase in diatoms due to marked rainfall, the subsequent intense consumption of nutrient salts by these plankton, and the utilization of very low concentrations of nutrient salts by C. antiqua.


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