洪湖主要沉水植物群落的定量分析 Ⅳ.穗花狐尾藻+微齿眼子菜+金鱼藻群落
QUANTITATIVE ANALYSIS ON THE MAIN SUBMERGED COMMUNITIES IN HONGHU LAKE. Ⅳ. MYRIOPHYLLUM SPICATUM + POTAMOGETON MAACKIANUS + CERATOPHYLLUM DEMERSUM COMMUNITY
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摘要: 穗花狐尾藻+微齿眼子菜+金鱼藻群落是洪湖沉水植被的一种重要群落类型,种类组成比较复杂,受干扰程度相对较低,各组成种类数量特征的变化基本上反映了各自的生活史特征.不同季节穗花狐尾藻、金鱼藻和微齿眼子菜的优势地位转换构成了该群落的重要特征.群落的生物量峰值在夏季出现,约为940gm-1(干重).群落水平结构比较均一,重直结构主要取决于优势种生物量的空间分布.群聚分布是各组成种的主要分布方式.分析结果表明,群落中各个种之间在分布上一般不表现出显著的联结关系,尽管在生物量分布上会出现一些重叠.穗花狐尾藻和微齿眼子菜在夏季表现出来的联结关系与绞草活动的影响紧密相关,也在一定程度上反映了取样面积的影响.Abstract: Myriophyllum spicatum + Potamogeton maackianus + Ceratophyllum demersum community was an important community type in Honghu Lake, with complicated species comppsition. The changes of the quantitative characters of every species coincided with their life history features as the result of relatively fewer harvesting activities of local fishermen in this community. The dominance alternation of M. spicatum.C. demersum and P. maackianus in different seasons was the most outstanding dynamic feature of the community. Peak biomass of the community, about 940 g dw m-2 occurred in summer. Horizontal structure of the community was fairiy homogeneous, and its vertical structure was closely related with the biomass distribution of the main dominant species in water column. Aggregation was the main spatial distribution pattern. In general no significant association was found for every species pares, although their biomass could show somewhat overiap. The significant association of M. spicatum and P. maackinus in summer was the result of restoration of the latter after being selectively used. This result also showed the effect of sampling area.