Growth of seagrass Halophila ovalis at dugong trails compared to existing within-patch variation in a Thailand intertidal flat
Growth of seagrass Halophila ovalis at dugong trails compared to existing within-patch variation in a Thailand intertidal flat
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儒艮小道上海草卵形盐藻的生长情况与泰国潮间带现有斑块内变化的比较
DOI：
10.3354/meps184097
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发表时间：
1999
影响因子：
2.5
通讯作者：
K. Aioi
中科院分区：
文献类型：
--
作者：
M. Nakaoka;K. Aioi
我们研究了小规模的变化形态和生长速度的海草Halophila卵形在泰国海岸的潮间带的海草床受到儒艮放牧。我们的目标是检查是否形态和生长速度不同的根茎在不同位置的斑块内（中心，边缘和儒艮小径），并测试是否H。卵圆藻对儒艮摄食的干扰表现出可塑性生长反应。海草生物量和叶密度在补丁中心比补丁边缘和儒艮小径大3至4倍。相反，在斑块边缘和儒艮小径，根茎的分枝率和节间长度显著大于斑块中心。对H. ovalis揭示，净生产量、叶片生产量和根茎伸长速率在斑块边缘比在中心大2 - 3倍。增长和生产率在边缘的儒艮步道和模仿儒艮步道的人工步道没有显着高于补丁中心。然而，一些形态参数，如分支频率和节间长度的显着差异，儒艮步道和斑块中心之间的形态变化表明，在H。可以在短时间尺度上诱导椭圆形。H.估计儒艮草食动物对卵圆虫的干扰是相当迅速的（<20 d）。H.椭圆形的可能是负责其持久放牧儒艮。
We studied small-scale variation in morphology and growth rate of the seagrass Halophila ovalis in an intertidal flat of Thailand coast where the seagrass bed is subjected to grazing by dugongs. Our objectives were to examine whether morphology and growth rate differ between rhizomes in different positions within a patch (center, edge and dugong trails), and to test whether H. ovalis shows plastic growth response to disturbance by dugong feeding. Seagrass biomass and leaf density were 3 to 4 times greater at the patch center than the patch edge and the dugong trails. In contrast, branching rate and internode length of rhizomes were significantly greater at the patch edge and dugong trails than at the patch center. The results of marking experiments of H. ovalis revealed that net production, leaf production and rhizome elongation rates were 2 to 3 times greater at the patch edge than at the center. Growth and production rates at the edge of the dugong trails and artificial trails mimicking dugong trails were not significantly higher than at the patch center. Nevertheless, significant differences in some morphological parameters such as branching frequency and internode length between the dugong trails and the patch center suggest that morphological changes in H. ovalis can be induced over short time scales. Recovery of H. ovalis atter disturbance by dugong herbivory was estimated to be quite rapid (<20 d). High growth rates of H. ovalis were probably responsible for its persistence under grazing by dugongs.