【摘要】 本文报导了1982—1983年,以及1984年2月和5月在北碚黛湖水域调查采集的藻类植物中的硅藻,初步鉴定的硅藻有74个种和变种,分别属于2纲、6目、10科、19属.其中短缝藻属的3个种,即粗壮短缝藻大形变种Eunotia robusta var.grandis Cleve—Euler、粗壮短缝藻白氏变种 E.robusta var.Bergii和也兰短缝藻 E.Jemtlandica(Font.)mh.,是我国文献记录尚未列入的.报告分析了黛湖硅藻区系成分,并对其种类、数量变化和生态分布等问题作了初步探讨.结果表明黛湖硅藻的种类多,个体数量少.而且常见的种类大部分属于微污水带,少量属于乙型中污水带的指示植物.因此,可以肯定黛湖是目前污染较轻,水质较清洁的一个水体.由黛湖硅藻数量变化资料的分析,可以确定双壳缝目硅藻是黛湖浮游硅藻的优势种类.在黛湖中还有几种热带硅藻,例如,胀大桥弯藻,纤细异极藻和某些双菱藻等,这是值得注意的现象,它将有助于了解黛湖硅藻区系的形成与发展.更多还原

【Abstract】 The present paper reports the diatoms investigated and collected in Dai Lake area of Jinyun Mountain, Beibei, Chongqing, during the years of 1982 to 1983 and February May 1984. Of these diatom specimens 74 species and varieties belonging to 19 genera, 10 families, 6 orders and 2 classes have been examined initially. Among them three speccies in the genus Eunctia, viz. , E. robusta var. grandis Cleve-Euler, E. robusta var. Bergii, and E. jemtlandica (Font.) mh. are not recorded yet in Chinese literature.In this paper, authors have analysed the diatom floral elements of Dai Lake area and dealt with their quantitative changes and their ecological distributions tentatively. The results show that the diatom flora of Dai Lake is abundant, whereas the amount of individual in every species is comparatively scarce. Furthermore, most of the diatoms commonly found in this area are indicator plants belonging to oligosaprobic and β-mesosaprobic zones. Hence it follows that Dai Lake may be recognized as a slightly polluted pond in which waters are relatively clean now. By analysing the data of diatoms found in Dai Lake from quantitative changes during recent years, we consider that a large number of plankton diatoms in the order Biraphidinales are predominant. There are several species of tropical diatoms, such as Cymbella turgidula Grun., Gamphonema gracile Ehr. and a certain species in the genus Surirella found in Dai Lake. It is a noticeable phenomenon which will be of much help for us to understand the formation and development of the diatom flora in this area.更多还原