河套地区几种沉水植物无性繁衍特性研究

Study on some submerged plants' asexual reproduction in Hetao Irrigation area

沉水植物对于湖泊生态系统有着重要的作用,它们不仅是水生环境食物链中重要的生产者,同时还对湖泊的营养物沉积和循环有着重要的作用,从而影响着湖泊的富营养化进程。本文以黄河内蒙古段河套灌区湖泊中常见的三种沉水植物篦齿眼子菜(Potamogeton pectinatus)、穿叶眼子菜(Potamogeton perfoliatus Linn)和狐尾藻(Myriophyllum verticillatum)为研究对象,对其无性繁殖方式和能力进行了初步研究。观察了这三种植物的营养繁殖结构,并利用茎节切段进行了人工培养试验。结果表明:三种植物均具有很高的营养繁殖潜力。由茎节处萌发新芽和新根并逐渐形成完整的植物体。植株地上部分截断后扦插及漂浮水中处理的成活率较高。而截断后的地下根茎及匍匐茎埋入淤泥后成活率极低。根据三种植物的营养繁殖潜力,探讨了人为收获这些植物的可能性以及其利用潜力。同时,评估了收获这些植物可能对湖泊水生植物群系改变以及湖泊富营养化转型的风险。

Submerged Plant plays an important role in lake ecosystem,which is not only a primary producer in the food chain,it also plays a major role in lake nutrient accumulation and circulation,thus,having a great influence on the eutrophication process of lakes.This thesis studies on the reproductive biology of three submerged plants（Potamogeton pectinatus,Potamogeton perfoliatus and Myriophyllum verticillatum） in the Yellow River Hetao irrigation area of Inner Mongolia.The structures of vegetative propagation organs of the three plants were observed.Segments of the aboveground shoots and rhizomes of the three plants were subjected to different treatments for their asexual reproduction capacities.The results show that shoot segments can live in the water for a long period.Potamogeton pectinatus and Potamogeton perfoliatus have a similar growth pattern.All the three plants showed a great vegetative reproduction potential.Above-ground segments have high survival rates when submerged into the water.However,rhizome segments have low survival rates when embedded into mud.On the bases of the vegetative reproduction behaviours of these plants,the risk of lake eutrophication type shifting was discussed if the submerged plants were not properly harvested.