Comparison of benthic algal composition developed on different substrata in Lake Donghu, Wuhan

Abstract

测定了富营养化武汉东湖中的底栖藻类在不同人工基质上建群发展为成熟群落的生物量(Chl.a),定性分析了人工和天然基质上成熟硅藻群落的种类组成和结构特征.通过比较建群期间底栖藻类在花岗岩、玻璃、塑料(PVC)和木板4种不同人工基质上的生物量变化,发现底栖藻类在PVC上的生物量峰值(Chl.a,71.0μg/cm²)明显高于其它人工基质,说明PVC是最适合底栖藻类生长的人工基质.分析发现人工基质花岗岩上底栖硅藻群落的种类组成、主要优势种类、群落的相似性指数、多样性指数都和天然基质上的硅藻群落是高度相似的,显示该人工基质能够代表天然基质上的藻类群落,表明花岗岩应该是以底栖藻类作指示生物监测和评价水质的理想人工基质.;Biomass (Chl.a) of benthic algae colonized and developed mature community on different artificial substrata was determined in eutrophic lake Donghu, and species composed and structure characteristic of mature diatom communities on artificial and natural substratum were analysed qualitatively. Biomass variance of benthic algae was compared on four different artificial substratum, granite stone, glass, plastic (PVC) and pine wood during the colonization period, and the peak biomass of benthic algae (Chl.a, 71.0μg/cm²) on PVC was significantly higher than that of the other artificial substrata, which showed PVC was the most suitable artificial substratum for benthic algae. Species composition, dominant species, similarity index and diversity index of benthic diatom communities showed a relatively high degree of consistency between natural and granite artificial samplers, which suggested granite should be the most favourable artificial substratum with benthic algae used as indicatory biology that monitored and evaluated water quality.