珠海淇澳岛红树林和芦苇湿地底栖硅藻群落比较

Comparison of Benthic Diatom Assemblages from Mangrove and Reed Wetland in Qi’ao Island, Zhuhai, Guangdong Province, China

摘要:

研究了珠海淇澳岛红树林湿地和芦苇湿地2007年3月至2008年1月间底栖硅藻群落的结构及其动态特征。结果表明，两种湿地共有底栖硅藻28属113种(变种)，其中红树林中检出23属95种(变种)，明显高于芦苇湿地的21属42种(变种)。底栖硅藻的丰度为14.3~553.5 cells cm-3，不同样地和采样期的多样性指数和均匀度指数不同，但红树林湿地高于芦苇湿地。两种湿地底栖硅藻群落的属种结构存在显著差异，红树林湿地中多以羽纹藻类，如布纹藻属(Gyrosigma)、斜纹藻属(Pleurosigma)和羽纹藻属(Pinnularia)等占优势，而芦苇湿地主要以中心藻类，如圆筛藻属(Coscinodiscus)和小环藻属(Cyclotella)等占优势。相似性分析显示，样地基质对底栖硅藻群落的影响大于季节变化的影响。

Abstract:

The structure, species composition and seasonal dynamics of benthic diatom assemblages in two kinds of wetland, mangrove and reed wetland, in Qi’ao Island, Zhuhai were investigated from March 2007 to January 2008. Samples of surface sediment layer (5 cm) were collected and detected under microscope. There were 113 taxa benthic diatom belonging to 28 genera, of which 95 taxa in mangrove and 42 taxa in reed wetland. Abundance of benthic diatoms ranged from 14.3 to 553.5 cells cm-3. The diversity indices and evenness index varied greatly in different sites and sampling time, but those in mangrove were higher than those in reed wetland. Species composition significantly differed in the two sites. Pennales, such as species from Gyrosigma, Pleurosigma and Pinnularia were dominant in the mangrove, while Centrales dominated in the reed wetland, such as Cyclotella and Coscinodiscus. Analysis of similarity indicated that the effects of site sediment were more important than that of season.