沉积物对潮下带岩礁上铜藻早期定居阶段的影响  

Effects of sediment on the early settlement stage of Sargassum horneri on rocky subtidal reefs.

作　　者：毕远新[1] 章守宇[1] 吴祖立[1] 

机构地区：[1]上海海洋大学海洋科学学院,上海201306

出　　处：《应用生态学报》2013年第5期1439-1445,共7页Chinese Journal of Applied Ecology

基　　金：国家海洋公益性行业科研专项(201005013-3);国家自然科学基金项目(41176110)资助

摘　　要：采用沉积物捕获器和抽吸泵测量不同站点和不同水深的沉积物相对数量,通过现场测量铜藻的分布密度,评估了枸杞岛潮下带铜藻分布与沉积水平和暴波强度的关系,并通过试验研究了不同沉积水平对铜藻幼孢子体附着和附着后藻苗存活的影响.结果表明:沉积物少且暴波强度小的站位铜藻分布密度最高,沉积物数量多、暴波强度高的站位铜藻分布稀少;在不同水深处,铜藻分布密度与沉积物数量呈负相关关系;附着基上沉积物数量干质量达到10.47 mg·cm^(-2)(0.543 mm厚)时,仅4.4%的铜藻幼孢子体能够附着,当沉积数量为13.96 mg·cm^(-2)(0.724 mm厚)时,则完全阻止幼孢子体附着;幼孢子体附着1周后,沉积物覆盖数量达到13.96 mg·cm^(-2)时,铜藻幼苗仍有24.0%存活,当沉积物覆盖数量达到34.9 mg·cm^(-2)(1.81 mm厚)时,铜藻幼苗全部死亡.总的来说,铜藻分布密度不但与沉积数量有关,在一定程度上还受暴波强度制约,沉积物对铜藻早期定居阶段的影响在铜藻种群分布上起到决定性作用.By using sediment trap and suction pump to measure the relative sediment levels across different sites and water depths, and through the in situ measurements of Sargassum horneri densi- ty, this paper assessed the relationships between the distribution of S. horneri and the sediment levels and wave exposure on the rocky subtidal platforms around Gouqi Island, China. The laborato- ry-based experiments were also conducted to test the effects of different sediment levels on the at- tachment of S. horneri zygote and the survival rate of S. horneri germling after the attachment. S. horned predominated at the sites with lesser sediment and wave exposure, but less distributed in the sites with high level sediment and wave-exposure. At different water depths, the distribution of S. horneri was negatively correlated with the amount of sediment. A medium dusting （dry mass 10.47 mg · cm-2, approximate 0. 543 mm deep） of sediment on the plate reduced the percentage of S. horneri zygotes attached to the substratum by 4.4%, and a heavy dusting （dry mass 13.96 mg·cm-2, approximate 0.724 mm deep） of sediment on the plate completely prevented the attachment. One week after the settlement of the zygotes, there were 24% of the germlings still sur- vived when the dry mass sediment coverage was 13.96 mg · cm-2. However, when the dry mass sediment coverage was up to 34.9 mg · cm-2 （ approximate 1.81 mm deep）, 100% of the germ- lings died. Overall, the distribution of S. horneri was not only related to sediment level, but also restricted by wave exposure to some extent. Sediment level was a critical factor affecting the distri- bution of S. horneri, particularly at its zygote attachment stage.

关 键 词：大型海藻 附着 附着基 暴波 

分 类 号：X172[环境科学与工程—环境科学]