三亚岩相潮间带底栖海藻群落结构及其季节变化

为了解三亚潮间带大型海藻生态现状,布设6条岩相断面,于2008年1—11月进行了四季野外的调查,并使用物种多样性指数与聚类分析研究了潮间带大型海藻四季的群落结构和多样性变化。调查共鉴定出大型底栖藻类130种,隶属于4门75属,其中红藻门41属67种、褐藻门16属31种、绿藻门15属29种、蓝藻门3属3种。潮间带海藻种类数季节变化不大,并呈低潮带>中潮带>高潮带的垂直分布特征,且中低潮带有共同分布种,夏季尤为普遍。潮间带海藻夏冬两季平均生物量高于春秋两季,但并无显著差异。优势种季节变化明显:春季有波利团扇藻Padina boryana、日本仙菜Ceramium japonicum、半叶马尾藻Sargassum hemiphyllum、海柏Polyopes polyideoides,夏季有波状软凹藻Chondrophycus undulates、冠叶马尾藻Sargassum cristaefolium、宽扁叉节藻Amphiroa dilatata、石花菜Gelidium amansii,秋季有冠叶马尾藻、波状软凹藻、叶状铁钉菜Ishige foliacea,冬季有瓦氏马尾藻Sargassum vachellianum、苔状鸭毛藻Symphyocladia marchantioides、珊瑚藻Corallina officinalis、波利团扇藻、日本仙菜。群落多样性冬高夏低:Shannon多样性和Margalef丰富度指数最大值出现在冬季,Shannon多样性和Pielou均匀度指数最低值出现在夏季。区域底栖藻类以暖水性热带-亚热带种为主,其次为温水性的暖温带种类,基本符合南海南区暖水区系特点。研究表明,尽管三亚潮间带底栖海藻种类数与生物量上并无显著的季节差异,但群落结构与多样性均显示出一定的季节变化。

Community structure of benthic algae and its seasonal variation in the rocky intertidal zone of Sanya

In order to investigate the current situation of benthic algal community in the intertidal zone of Sanya, field sampling was carried out including six rocky intertidal sections from Jan. 2008 to Nov. 2008. The changes of community structure and diversity of benthic algae in the intertidal zone were analyzed by species diversity indices and cluster analysis. A total of 130 species in four seasons were identified, among them, 67 species of 41 genera belong to Rhodophyta, 31 species of 16 genera belong to Phaeophyta, 29 species of 15 genera belong to Chlorophyta and 3 species of 3 genera belong to Cyanophyta. Species number altered slightly in four seasons, and its vertical distribution indicated a decreasing trend along with increased vertical gradient. Moreover, mutual species were found at mid-tide and low-tide zone, especially during the summer. Although the average biomass of benthic algae in summer and winter seemed slightly higher than that in spring and autumn, there was no significant difference between them. Dominant species of benthic algae varied with different seasons, indicating their functions in the community changed with seasons. Dominant species were Padina boryana, Ceramium japonicum, Sargassum hemiphyllum, Polyopes polyideoides in spring; Chondrophycus undulates, Sargassum cristaefolium, Amphiroa dilatata, Gelidium amansii in summer; S. cristaefolium, C. undulates, Ishige foliacea in autumn; and, Sargassum vachellianum, Symphyocladia marchantioides, Corallina officinalis, P. boryana, C. japonicum in winter. The diversity index and Margalef's species richness peaked in the winter, while the diversity index and the Pielou's evenness bottomed in the summer. The benthic algae in the intertidal zone of Sanyaare mainly composed of tropical-subtropical species, followed by warm temperate species, which generally in accordance with the taxonomic features of the Southern South China Sea. These results suggest that the community structure and diversity of benthic algae in Sanya varies with seasons despite of no significant seasonal differences in species number and biomass.