若尔盖高原湿地藻类多样性研究

Research on Algal Diversity in Zoige Alpine Wetland

分别于夏、冬两季采集若尔盖高原湿地水样,利用传统培养及显微镜检的方法和现代分子生物学方法对其藻类多样性进行了研究.结果表明,夏季水样至少培养出4种绿藻,分别为普通小球藻(Chlorella vulgaris Beij.)、浮球藻(Planktosphaeriagelatinosa G.M.Smith)、繁茂栅列藻(Scenedesmus abundans Kirchner)和柱状栅列藻(Scenedesmus bijuga Turp.),均属于绿球藻(Chlorococcales),其中普通小球藻为优势藻种,并被分离纯化.显微镜检结果表明冬季水样中主要的藻类种群为硅藻,此结果符合在低温季节天然水体中常以硅藻为主的常理.蓝藻16S rRNA基因克隆文库中的主要类群为硅藻(Bacillaripiophyta,35.3%),其次为蓝藻,包括色球藻(Chroococcales,5.9%)、念珠藻(Nostocales,11.8%)、颤藻(Oscillatoriales,11.8%)和一些未知种属的蓝藻类群(Unclassified Cyanobacteria,35.3%),还发现一些与低温环境微生物相关的类群,如颤藻目细纤菌属(Leptolyngbya).

Water samples were collected in summer and winter in Zoige Alpine Wetland.Both the traditional cultivable and microscopic method and modern molecular approach were used to reveal the algal diversity in the wetland.For the samples collected in summer,single-cell Chlorophyta was cultured,isolated and identified.The results showed that there were at least four kinds of Chlorophyta,which were Chlorella vulgaris Beij.,Planktosphaeria gelatinosa G.M.Smith,Scenedesmus abundans Kirchne and Scenedesmus bijuga Turp.They all belonged to Chlorococcales.The dominant species was Chlorella vulgaris Beij.,which had been purified.For the samples collected in winter,the microscopic results showed that the dominant populations were diatoms,which is in accordance with the principle that the dominant populations of algae are diatoms in low-temperature seasons.Cyanobacterial 16S rRNA gene clone library showed that the dominant group was Bacillaripiophyta（35.3%）.And Cyanobacteria contained the orders of Chroococcales（5.9%）,Nostocales（11.8%）,Osillatoriales（11.8%） and Unclassified Cyanobacteria（35.3%）.There were some clones related to those from frigid habitats,such as Leptolyngbya-related clones.