deep water coral
deep water coral
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深水珊瑚
DOI：
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发表时间：
1993
期刊：
影响因子：
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通讯作者：
H. Fricke
中科院分区：
文献类型：
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作者：
P. Kaiser;D. Schlichter;H. Fricke
本文研究了采自亚喀巴海湾的脆弱细鳞珊瑚（Leptoserisfragilis）中与-共存的虫黄藻的光适应性。1988年夏天在110 - 120 m深度采集的标本移植到70 - 160 m。在每个深度处，个体暴露于其自然生长位置（口侧面向表面）或相反生长位置（口侧面向底部）。暴露1年后，收集珊瑚并分离虫黄藻。作为一个功能的光的深度和生长位置的可用性，几个藻类参数的变化，这是相关的光适应。虫黄藻在自然生长深度为116 m时的密度为0.15 × 106个× cm-2，在自然生长深度为160 m时，虫黄藻的密度为0.0034 × 106个× cm-2（A2%）。在同一深度（160米）的珊瑚口面向下，只能观察到退化的藻类。随深度增加，藻体体积由116 m处的728 × m3减少到160 m处的406 × m3，色素含量增加。每个细胞中多甲藻素的增加量很低（160 m时为116 m时的2倍）。叶绿素a，特别是叶绿素c2的浓度每细胞增加。与116米处的自然量相比，160米处的chl a高5倍，chl c2高8倍。在所有深度，每个细胞的叶绿素C 2含量都高于叶绿素a。讨论了作为光捕获器的叶绿素a/叶绿素c 2复合物的形成。以chlc2为主的捕光现象可以解释为一种特殊的色适应。fragilis在双重意义上：（1）在栖息地光短波长占主导地位。这种光可以直接吸收色素，如叶绿素a和叶绿素c2。(2)宿主色素吸收可见的紫光，并通过自发荧光将这些不适合光合作用的波长转换为更长的波长。发射的较长波长符合藻类色素的最大吸收。因此，宿主支持其共生体的光合作用。珊瑚暴露在160米深处，
Photoadaptations of zooxanthellae living with- in the deep water coral Leptoserisfragilis taken from the Gulf of Aqaba (Red Sea) were studied. Specimens - col- lected in summer 1988 between 110 and 120 m depth - were transplanted to 70 and 160 m. At each depth indi- viduals were exposed in their natural growth position (oral side facing the surface) or in a reverse growth posi- tion (oral side facing the bottom). After 1 yr of exposure the corals were collected and the zooxanthellae were iso- lated. As a function of the availability of light with depth and growth position several algal parameters showed changes which are related to photoadaptations. The rela- tively low density of zooxanthellae of 0.15 x 106 cells x cm -2 at a natural growth depth of 116 m de- creased to 0.0034 x 106 cells x cm -2 (A2%) at 160 m in specimens growing with a natural orientation. In corals with a downward-facing oral surface at the same depth (160 m) only degenerated algae could be observed. With respect to depth dependence the volume of the algae de- creased from 728 ixm 3 at 116 m to 406 ~tm 3 at a depth of 160 m and the content of pigments increased. The aug- mentation of peridinin per cell was low (two times at 160 m compared to 116 m). Chlorophyll a and in particu- lar chlorophyll c2 concentrations per cell were enhanced. Compared to natural amounts at 116 m, chl a was five times and chl c2 eight times higher at 160 m. At all depths the chl c 2 content per cell was higher than for chl a. The formation of chl a/chl c 2 complexes as light harvestor is discussed. Light harvesting, with chl c2 prevailing may be explained as a special type of chromatic adaptation of L. fragilis in a double sense: (1) in the habitat light short wavelengths predominate. This light can be directly ab- sorbed with pigments such as chl a and chl c2. (2) Host pigments absorb visible violet light and transform these wavelengths, less suitable for photosynthesis, into longer ones by means of autofluorescence. The emitted longer wavelengths fit the absorption maxima of the algal pig- ments. Thus the host supports photosynthesis of his sym- bionts. Corals exposed at 160 m depth with a downward