水生态学杂志Issue(2)：11-17,7.DOI:10.15928/j.1674-3075.2015.02.003
北京翠湖湿地血红裸藻水华发生的环境条件
Environmental Variables Influencing Euglena sanguinea Blooms in Cuihu Lake Wetland in Beijing
摘要
Abstract
Shallow lake wetlands play an important role in climate regulation in Beijing.Eutrophication in the shal-low lakes of Beijing is serious because of limited water resources and the high volume of waste water discharged. Research on algae blooms in urban shallow lakes has been limited,especially research on the environmental varia-bles that induce algae blooms in shallow lake wetlands with high nutrient concentration and low flow.Cuihu Lake, located in Shangzhuang Town,Haidian District,Beijing,with a water area of 700 hm2 and average depth 1.2 m,is basically static and water recharge depends on direct runoff augmented by pumping from Shangzhuang Reservoir. The frequent occurrence of algae blooms in Cuihu Lake Wetland has been the primary environmental problem over the past 10 years.The aim of this study was to clarify the environmental conditions leading to algae blooms in Cuihu Lake and to reveal the relationship of Euglena sanguinea blooms with environmental variables by canonical corre-spondence analysis (CCA),which will supply useful data for ecological regulation.In July of 2013 during the wet season,an investigation was conducted at 27 sampling sites of the Cuihu Lake Wetland where algae blooms oc-curred.A total of 81 algae samples were collected (triplicate samples at each site)and fixed with Lugol's solution for species identification and counting in laboratory.Ten water quality parameters were also measured at each site:pH,water temperature (WT),dissolved oxygen (DO),electrical conductivity (EC),total phosphorus (TP),to-tal nitrogen (TN ),spatial location quantified according to the wind direction (WIND),photo flux density (PPFD),the movement of surface water (FLUC)as determined by the drifting buoy method,and cover (the area shaded by emergent aquatic plants ,shrubs and trees).A total of 12 genera and 30 algae species were detected at the 27 sampling sites and species common to all sites included Euglena sanguinea,Oscillatoria Formosa,Meris-mopedia tenuissima,Cryptomonas ovata,Gymnodinium aerucyinosum,Chlamydomonas sp.,Navicula sp.,Chroo-coccus sp.,Anabeana sp.,Synedra sp.,Rhabdogloea sp.and Scenedesmus obliquus.Among them,Euglena san-guinea was the dominant species.The ratio of N /P ranged from 8.33 -35.32,with a mean value of 16.38,indi-cating that the N /P ratio was not the crucial factor inducing algae blooms in study area.The relationship of phyto-plankton abundance with the 10 environmental variables by CCA revealed that the production of Euglena sanguinea in Cuihu Lake was significantly affected by TP content,but not by TN content.The optimal temperature for the growth of Euglena sanguinea was 26 -28℃ and the species displayed significant positive correlation with PPFD. High illumination intensity produces higher frequency blooms of Euglena sanguinea because of the phototaxic capa-bility of the species.In conclusion,light intensity,water movement,wind direction,water temperature and pH are the critical environmental variables influencing the algae community in urban shallow lakes.Thus Euglena sanguin-ea blooms can be inhibited by controlling water temperature,improving flow fluctuation frequency and increasing the area shaded by plants.关键词
血红裸藻/翠湖湿地/环境条件/水华Key words
Euglena sanguinea/Cuihu Lake Wetland/environmental factors/algae bloom分类
资源环境引用本文复制引用
赵欣胜,崔丽娟,李伟,张曼胤,商晓静,张岩..北京翠湖湿地血红裸藻水华发生的环境条件[J].水生态学杂志,2015,(2):11-17,7.基金项目
国家林业公益性行业科研专项（201204201）；国家自然科学基金资助项目（50809005）。 （）
