Studies on Morphology and Physiological Ecology of Laminaria (Phaeophyta)

1999年10月至2002年7月，在松岛湾对日本海带（Laminaria japonica）、L. religiosa、L. ochotensis和L. angustata的形态和生理生态进行了比较研究。此外，研究了海湾浮游植物的海洋条件和动态，探讨了海带的营养吸收能力对赤潮的预防作用。在形态和生理特征相同的情况下，认为人工栽培的日本乳草、宗教乳草和蛇叶乳草是同一种，只有奥古斯达乳草是不同种。在冬季至夏季，海带物种适应水温，在其分生组织以外的层中保持较高的光合作用速率和分生组织中较高的营养吸收速率。结果表明，分生组织中积累了丰富的碳和氮。生长早期（12月）开始的尖层侵蚀也促进了分生组织中碳氮的积累。分生组织中丰富的碳氮积累保证了秋季的成熟和次年冬季的再生。冬春季低温高营养复合水文条件下，海带的光合速率和养分需求持续高，海带收获丰富。松岛湾浮游植物种类以硅藻为主，赤潮种类较少。水柱中的硅藻种群全年都是由它们在泥泞的底部发现的静止孢子维持的。

Studies on Morphology and Physiological Ecology of Laminaria (Phaeophyta)Comparative studies on morphology and physiological ecology of Laminaria japonica, L. religiosa, L. ochotensis, and L. angustata cultivated on long-lines were carried out in Matsushima Bay from October 1999 to July 2002. Additionally, oceanographic conditions and dynamics of phytoplanktons in the bay were investigated to explore the possibility of prevention of red tide by the nutrient uptake capacity of Laminaria. It was considered that cultivated L. japonica, L. religiosa and L. ochotensis were same species as morphological and physiological features were identical, but only L. augustata was a different species. During winter to summer, Laminaria species adapted to water temperature, sustained high photosynthesis rates in their lamina excluding meristems and high nutrient uptake rates in their meristems. As the results, abundant carbon and nitrogen were accumulated in the meristems. The erosion of the tip lamina initiating from early growing period (December) also contributed to accumulations of carbon and nitrogen in the meristems. The accumulation of abundant carbon and nitrogen in the meristems ensure the maturation in fall and regrowth in the next winter. Harvest of Laminaria species appear to be abundant under the combined hydrographic condition of low temperature and high nutrient level from winter to spring as high photosynthesis rates and nutrients requirement were sustained during the period. Dominated phytoplanktonic species were diatoms and few red tide species were found in Matsushima Bay. Diatom populations in water columns were sustained from their resting spores found in muddy bottoms throughout the year.