广西防城港东湾红树林污损动物的种类组成与数量分布特征

CHARACTERISTICS OF QUANTITATIVE DISTRIBUTION AND SPECIES COMPOSITION OF FOULING FAUNA IN DONGWAN MANGROVE STANDS OF FANGCHENGGANG, GUANGXI

对白骨壤(Avicenniamarina)树上的污损动物进行了定性和定量调查。共采得污损动物9种。以白条地藤壶(Euraphiawithersi)和潮间藤壶(Balanuslittoralis)在多数采样点的附着密度最高,但二者在树上的分布有明显的差异;团聚牡蛎(Ostreaglomerata)分布最广,是惟一一种在各采样点均能采到的污损动物;黑荞麦蛤(Xenostrobusatraus)主要分布在树干和较粗的枝条上,其密度在向海林缘达到最大,超过牡蛎和藤壶的附着密度。污损动物附着高度与树高的比值(h∶H),主干、枝条和叶片上附着的污损动物总量均随林带离岸距离增大而增大,呈明显的变化趋势。

Fouling fauna attaching to the mangrove species Avicennia marina was investigated qualitatively and quantitatively. Nine species of fouling fauna were identified. The individual densities of Euraphia withersi and Balanus littoralis were rather high at most sampling plots, but their distributions on the plants were distinctively different. Ostrea glomerata was most popular, which was the only species collected at all sampling plots. Xenostrobus atraus attached mainly to lower trunks, and its individual density was the highest at the seaward fringe belt of the mangrove, surpassing the individual densities of both oysters and barnacles. The ratio of attaching height to tree height (h/H) and the total amount of fouling faunas attaching to trunks, branches and leaves increased obviously with the distance off the coast.