Abstract The solitary ascidian Phallusia nigra is commonly found on hard substrates along the Jeddah coastal waters of the central Red Sea. In this study, the recruitment pattern of P. nigra on artificial substrates was assessed in relation to their type, surface color and orientation. The results showed a higher recruitment rate of the ascidian species on concrete and dark panels. The abundance of the ascidian on test panels varied between the four seasons. The orientation (vertical or horizontal) of the panels did not show any major difference in the recruitment. Significant effects of light intensityon the recruitment of P. nigra were observed on test panels, with higher abundance on panels submerged in the shade. In conclusion, this study clearly indicates the importance of the type and color of substrates in the recruitment of ascidians on artificial materials.

中文翻译：

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1816 年，在沙特阿拉伯红海中部淹没的人工基质上，单独的海鞘 Phallusia nigra Savigny 的募集模式

摘要 孤立的海鞘 Phallusia nigra 常见于红海中部吉达沿海水域的坚硬基质上。在这项研究中，根据类型、表面颜色和方向评估了人工基质上黑质假单胞菌的募集模式。结果表明，混凝土和深色面板上的海鞘物种具有更高的补充率。测试板上海鞘的丰度在四个季节之间有所不同。面板的方向（垂直或水平）在招募中没有显示出任何重大差异。在测试面板上观察到光强度对 P. nigra 募集的显着影响，在淹没在阴影中的面板上具有更高的丰度。综上所述，