2023 年 11 巻 1 号 論文ID: 23-00110
Field observation of chlorophyll fluorescence and laboratory experiments were conducted on the oxygen consumption rate of the causative red-tide dinoflagellate Akashiwo sanguinea to estimate the nighttime oxygen consumption rate by algal respiration in the field. The estimated oxygen consumption rate based on these data was compared to the oxygen consumption rate of suspended solids and sediments in previous studies. Diurnal vertical migration of dinoflagellates and their nighttime respiration in the bottom layer contributed significantly to hypoxia and oxygen consumption through suspensions and sediments. Furthermore, based on the continuous observation results, the diurnal vertical migration of A. sanguinea was remarkably reduced during the period of development of hypoxia with oxygen saturation below 20%. This suggests that the hypoxia levels affect the patterns of A. sanguinea migration.
