雷州半岛东南海域污损浮标的大型藻类

摘要

大型藻类是海洋污损生物群落中的常见类群,其附着会破坏浮标防护涂层,增加浮体重量,增大水流拖曳力,导致腐蚀危害风险升高,甚至可能造成浮标移位,从而缩短相关设施的工作时间.为探讨热带海区冬季浮标大型藻类附着污损状况及其与浮标布设时间的关系,于2015年2月初,对布设在雷州半岛东南海域2个近岸浮标上附着的大型海藻进行采样分析.结果表明,该海域浸海时间6个月的浮标A,浮体侧面仅附着浒苔(Enteromorpha prolifera)和石莼(Ulva lactuca)2种大型绿藻,而在浸海时间19个月的浮标B上,共采集到绿藻门的浒苔、肠浒苔(E.intestinalis)、石莼、裂片石莼(U.fasciata)和红藻门的舌状蜈蚣藻(Grateloupia livida)、柔质仙菜(Ceramium tenerrimum)6个种类.浮体侧面下部和浮底没有采集到大型污损藻类.浒苔、肠浒苔、石莼、裂片石莼为喜强光藻类,繁殖力强,配子或孢子在浮体固着形成一定生物量的种群后,不太喜光的舌状蜈蚣藻和柔质仙菜才出现,表现出先附着绿藻后附着红藻的着生规律,且浮标浸海时间越长,污损藻类的种类越多.浮体水线部位的污损主要由绿藻引发,而红藻则多出现在浮体侧面浸没区域略深的部位,这种格局应与藻类所含色素的种类和比例及光线在海水中的穿透性等因素密切相关.研究结果可为航标污损生物防治和南海大型藻类生态研究提供基础资料.%Macroalgae are common constituents of fouling communities. Their colonization can damage protective coatings, add loading, increase corrosion risk and even may result in position change of buoys. Under such circumstances the service time of buoys will be shortened. In order to elucidate the fouling pattern of macroalgae in winter on buoys deployed in waters southeast of the Leizhou Peninsula, located in tropical zone, northern South China Sea and the relationship between the macroalgal community and duration of buoy deployment, a navigation buoy investigation was conducted in early February 2015. The results indicate that only 2 species of green algae,Enteromorpha prolifera and Ulva lactuca, were observed on the water line of buoy A, which was deployed for 6 months. However, a total of 6 species, including the green algae,E. prolifera,E. intestinalis,U. lactuca, and U. fasciata, and red algae Grateloupia livida and Ceramium tenerrimum, were identified from the samples collected on the water line and submerged upper side hull of buoy B deployed for 19 months. No algae were found on the lower part of the side hull and bottom of both buoys. It can be concluded that colonization of green algae occurred earlier than the red algae and the number of species of fouling macroalgae increased with time. The green algae,E. prolifera,E. intestinalis,U. lactuca and U. fasciata, favour strong light and have vigorous reproductive capacity and were the forerunners in the algal fouling community. Moreover, water line regions of buoys were fouled by green algae and slightly deep parts mainly by red algae, particularly C.tenerrimum. The vertical distribution pattern should be closely related to the type and proportion of pigments in macoralgae and the penetrability of light in seawater. This study provides basic data useful for the prevention and control of fouling organisms on navigation buoys in the northern South China Sea and it may also be helpful in understanding the ecology of macroalgae on artificial facilities in the South China Sea.