淀山湖水生维管束植物群落研究

A STUDY ON THE COMMUNITIES OF AQUATIC VASCULAR PLANTS IN DIANSHAN LAKE

论述了淀山湖水生维管束植物的种类组成、分布、群落类型、群落的数量特征及演替。结果是:（1）湖中分布有26种水生维管束植物,隶属16科,21属;其优势种为苦草、菹草、马来眼子菜、芦苇等。（2）湖中水生植被呈不规则环带状分布,并可划分为挺水、浮叶、沉水三个植物带,12个主要水生维管束植物群落。（3）水生维管束植物的重要值以苦草最大,茨藻属植物最小。（4）淀山湖水生维管束植物群落有由沉水型向浮叶型、挺水型或漂浮型过渡的趋势。

Dianshan Lake, which lies in the border of Jiangsu Province, Zhejiang Province and Shanghai Municipality?is the only freshwater lake in Shanghai Municipality with an area of 62km2. It is a shallow and passageway lake, averaging water depth of 2. 1m.Species composition, distribution, community type as well as quantitative characters and succession of aquatic vascular plant (AVP) communities in Dianshan Lake during 1991-1992 were studied. The results were summarized as follows:(1) There were 26 species of AVP, belonging to 21 genera and 16 families. Among them , Vallisneria asiatica, Potamogelon crispus, Potamogeton malaianus and Phraamites communis etc. were dominant species.(2) The distribution of aquatic vegetation in this lake exhibited irregular zonations, and might be classified into 3 plant zones (emerged plants, leaf-floating plants and submerged plants) from shore to center of the lake and 12 principal community types.(3) Among the importance values of main species of AVP communities, the maximum was that of V. asiatica and the minimun was those of Najas. The AVP communities were possibly undergoing the change from submerged plants to leaf-floating plants, emerged plants or floating plants.(4) The main environmental factors to restrict the growth and distribution of AVP were water depth, transparency of lake water, composition of sediment and artificial disturbance.