This study aims to investigate biometric parameters and epiphytic algae on the leaves of three seagrass species Posidonia oceanica, Cymodocea nodosa, and Halophila stipulacea, which co‐occur in Eastern coast of Tunisia (islet of Kaboudia, Chebba). Sampling was conducted at six stations (5 m depth) during March 2017. Biometrical measurements showed that shoot density and leaf surface area of P. oceanica and the C. nodosa were higher than those of H. stipulacea. Epiphyte covers were correlated with biometric parameters of the three host plants. Epiphyte algal assemblages were more abundant and more diversified on the leaves of P. oceanica and C. nodosa than those on the leaves of H. stipulacea. Significant differences were found for all epiphytic algae groups among the three seagrass species. Seagrass species characteristics (meadow type, shape forms of leaves, life span, and growth rate) seem to be responsible of these dissimilarities in epiphytic algae communities. No apparent negative interactions of H. stipulacea with P. oceanica and C. nodosa have been observed. No invasive epiphytic algae species were found on the leaves of H. stipulacea. It seems that it is a recent installation of H. stipulacea in this area since its density (average 416.23 shoot m⁻²) was relatively low.

中文翻译：

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切比（东突尼斯）海洋海草波塞冬草（L.）Deile，Cymodocea nodosa（Ucria）Asch和小腹吸虫Stipulacea（Forssk。）Asch叶片上附生藻类组合的比较。

这项研究的目的是调查突尼斯东部沿海（卡布迪亚岛，谢布巴岛）共生的三种海草物种大洋波塞冬，结节藻和嗜盐藻的叶片生物特征参数和附生藻类。2017年3月在六个站（5 m深度）进行了采样。生物特征测量显示，大叶黄杨和结节藻的枝条密度和叶表面积均比硬叶忍冬高。附生植物的覆盖率与三种寄主植物的生物特征参数相关。在P. oceanica和C. nodosa的叶子上，附生藻类组合更加丰富和多样化。比那些叶子H. stipulacea。在这三种海草物种中，所有附生藻类组均存在显着差异。海草物种特征（草甸类型，叶片形状，寿命和生长速率）似乎是附生藻类群落中这些差异的原因。尚未观察到叶拟南芥与P. oceanica和C. nodosa的明显负性相互作用。无侵入性附生藻类物种上的叶子中存在H. stipulacea。由于该地区的密度（平均416.23芽m ^-2）相对较低，因此似乎是该地区最近的一种安息草。