【摘要】 <正>藻类植物是一类种类多、分布广的低等植物,是水体中最重要的初级生产者,它们不仅是水中氧气的供给者,而且是浮游动物、虾类、鱼类的适宜的食物。化学分析表明,藻类植物中的蛋白质、脂肪、灰分的含量,几乎与好的牧草一样。并且由于其细胞壁较薄(有些鞭毛类根本就没有细胞壁),细胞又易破碎成柔软的碎片,极易被水生生物消化吸收,因此,对于水生动物是一种优于肉眼可见的水生维管束植物的营养食物。藻类植物的种类、数量及分布状况,直接影响着水产养殖业的发展。更多还原

【Abstract】 The aim of this study is to research the present condition of the Algal flora in the Dianchi Lake, to provide one of the scientific basis for the economic development of the lake resources. Complete collection were made during the years 1983-1984.205 species belonging to 8 phyla,21 orders,39 families and 81 genera were identified. Among them there are 90 species and varities of Chlorophyta, of which 66 spicies and varities are belong to Chlorococcales, Scenedesmus and pediastrum being dominant. The next is the Bacillariophyta with 48 species and varities, in which Melosira and Suriella are dominant genera. The third is Cyanophyta with 45 species and varities, the Microcystis being the dominant genus. Charophyta has not been collected.Cao-Hai, a part of the lake nearest to the city, owing to its lake surface has been greatly contracted and also severely polluted by the interference of human activities, the kinds and numbers of algal specimens are comparatively fewer than usual. These collections show that Euglonophyta is more conspicuous. The genera of Chlamydomonas, Pandorina and Polytoma of the Volvocales are more conspicuous too.In the outer part of the lake, on the other hand, kinds of algal vegetation are more numerous than those in the Cao -Hai of the Dianchi Lake, because the water region of the lake is broader and the quality of the water is better. Composition of the Algae are: Chrysophyta, Xanthophyta, Pyrrophyta, Crypto-phyta and Cyanophyta, In the Chlorophyta, the species of Tetrasporales and Desmidiales are commonly distributed in the outer part of the lake. Pediastrum simplex , Ceratium hirundinella , Oocystis lacustis , Coscinodiscus lacustris,Anphanocapsa pulchra are domiant Species. It is interesting to note that the Botryococcus braunii and pediastrum simplex are colleted only in the outer part of the lake. Another feature is that the number of Mougeotial is large, so people have the impression that the lake is rich in green filamentous algae.In summer time, or high temperature seasons quantites of Microcystis, Ana-baena, Aphanizmenon flos-aque and Oscillatoria tenus forming "water blossom" in the lake near the lakeside.Accordint to the historical reccords the Algal vegetation of the lake has changed very much from past to present times. for exempl, Charophyta plants have completely vanished and Ceratium cornutum has not been collected and the desmiales has become rare. The quotiont of Chlorococcales - Desmidiales has become higher to 7.7, which indicats that the lake water eutrophication is increasingly manifest. Pediastrum simplex, Ceratium hirundinella, Suriella sobusta are only distributed in the outer part of the lake, but not in Cao-Hai. Appatently, Melosira granulata and Oscillataria tenus and so on have become the main algae in the lake now.更多还原