珊瑚藻类钙化的研究

ON THE CALCIFICATION OF CORALLINE ALGAE

于1991年4—6月,在日本海若峡湾采集珊瑚藻类样品,采用钙镁离子定量的方法,对小珊瑚藻、异边孢藻和大边孢藻的Ga、Mg及其碳酸盐的含量,无机和有机态碳元素的量比以及前两种藻类的钙化与光合作用固碳速度进行了研究。结果表明,三种珊瑚藻类的碳酸盐占藻体干重的77％-80％,其中CaCO3占66％-70％,MgCO3占10％—11％。小珊瑚藻中Ga的含量比两种边孢藻高,而Mg的含量则比后两者低。小珊瑚藻与异边孢藻的钙化速度在高光照强度［300μmol／（m2·s）］下比光合作用固碳速度慢;而在低光照强度［50μmol／（m2·s）］下钙化速度比光合作用速度快。钙化与光合作用都受光的影响,但钙化对光的敏感度相对较低。

Samples of coralline algae were collected in Wakasa Bay, Japan Sea, during the period of April to June, 1991. The contents of calcium, magnesium and their carbonates, the ratio of inorganic to organic carbon and the carbon fixation rates by calcification and photosynthesis of Coralline pilulifera, Marginisporum aberrans and M. crassissimum were investigated in order to assess the extent of calcification in coralline algae. It was found that 77%-80% (weight) of the dry algal samples were made of the carbonates, 66%- 70% calcium carbonare and 10%- 11% magnesium carbonate. C. pilulifera contained more calcium and less magnesium than M. Aberrans and M. crassissimum. All of the species contained more inorgainc carbon than organic catbon; the ratio of inorganic to organic carbon was 1.4- 1.7. Calcification in C.pilulifera and M. Aberrans exceeded photosynthesis under low light intensity [(50μmol / (m2·s)], but was below it under high light intensity [(300μmol / (m2. s)]. The calcification process of the coraline algae is affected by light, but not so much as photosynthesis does.