Abstract：
Seagrass meadows serve as critical marine habitats, offering numerous benefits to both humans and wildlife. Taiping Island, situated in the South China Sea, has been historically known for its abundant seagrass meadows. However, satellite imagery suggested there was a low density of seagrasses around Taiping Island. On the other hand, many green turtles (Chelonia mydas) were observed from the shore. To investigate this phenomenon, we conducted drone surveys of the shallow reefs and discovered a density of 902 ± 601 (mean ± SD) individual turtles per square kilometer during high tides. In addition, we conducted a cage experiment to test the hypothesis that large herbivores are impacting seagrass abundance negatively. The results indicated that the blade lengths of seagrasses in cages were significantly longer than those outside. It is likely that large herbivores such as green sea turtles are the key consumers of seagrass on the shallow reef flats of Taiping Island. Accordingly, further research and management should take into account that the increasing number of sea turtles may deplete the seagrasses and have an impact on the seagrass ecosystems.
摘要：
海草草甸是重要的海洋栖息地，为人类和野生动物提供了许多好处。太平岛,位于南中国海，历史上一直以其丰富的海草草甸而闻名。然而,卫星图像显示，太平岛周围的海草密度较低。另一方面,从岸边观察到许多绿海龟（Cheloniamydas）。为了研究这种现象，我们对浅礁进行了无人机调查，发现在涨潮期间每平方公里的个体海龟密度为902±601（平均值±SD）。此外,我们进行了一个笼子实验，以验证大型食草动物对海草丰度产生负面影响的假设。结果表明，网箱中海草的叶片长度明显长于外部。绿色海龟等大型食草动物很可能是太平岛浅礁滩上海草的主要消费者。因此，进一步的研究和管理应考虑到海龟数量的增加可能会耗尽海草，并对海草生态系统产生影响。
