滆湖3个区域枝角类群落特征的对比研究

Comparison Study of Community Structure of Cladocera Between Three Regions in Lake Gehu

于2013年7月至2014年6月对滆湖鲢、鳙鱼控藻网围内、外和工程示范区3个区域的枝角类群落结构进行了对比分析。3个区域共鉴定出枝角类22种,主要优势种有:长额象鼻溞(Bosmina longirostris)、脆弱象鼻溞(B.fatalis)、角突网纹溞(Ceriodaphnia cornuta)、直额裸腹溞(Moina rectirostris)、镰角秀体溞(Diaphanosoma excisum)、长肢秀体溞(D.leuchtenbergianum)和微型裸腹溞(Moina micrura)等,3个区域种类相似,物种多样性无显著差异。枝角类生物密度:工程示范区(121.5±16.7)ind/L>网围外(38.7±20.6)ind/L>网围内(12.3±1.4)ind/L,生物量也呈同样趋势。冗余分析(RDA)结果表明,水温、高锰酸盐指数、溶氧、透明度和叶绿素a含量是影响枝角类生态特征分布的主要水质因子。结果显示,鲢、鳙鱼养殖会降低枝角类现存量,工程示范区有利于枝角类的生长和群落稳定。

From July 2013 to June 2014, comparative experiment was carried out to study the community structure of cladocera in three regions of Lake Gehu including engineering demonstration area, inside and outside of bio-manipulation area. In three regions, a total of 22 species of cladocera were identified, with dominant species throughout the year as Bosmina longirostris, B. fatalis, Ceriodaphnia cornuta, Moina rectirostris, Diaphanosoma excisum, D. leuchtenbergianum and Moina micrura and so on. The species of cladocera in three regions are similar, and there was no significant difference in species diversity. The density of cladoceras are： engineering demonstration area（121.5±16.7） ind/L outside of bio-manipulation area（38.7±20.6） ind/L inside of bio-manipulation area（12.3±1.4） ind/L. The trend of biomass is the same as density. The results of redundancy analysis（RDA） showed that the water temperature, permanganate index, dissolved oxygen, transparency and chlorophyll a were the main environmental variables affecting the community structure of cladoceras. Results show that the silver and bighead carp breeding will reduce the cladoceran biomass, engineering demonstration area is favorable for the growth and stability of the cladoceran community.