模拟水位对长喙毛茛泽泻种群的影响

Effects of Mimic Water-depth on the Ranalisma rostratum Population

在长喙毛茛泽泻（ＲａｎａｌｉｓｍａｒｏｓｔｒａｔｕｍＳｔａｐｆ）实验田中模拟出该种群生长的３种水生态位，即湿生、挺水、沉水。结果表明：在挺水状态下，长喙毛茛泽泻种群的株高、根系长度、纤匍枝节间长度、无性小株数、生殖力、总生物量都明显高于湿生和沉水状态。有性生殖和营养繁殖在挺水和湿生条件下都能正常进行，在湿生状态下种群倾向于有性生殖。在沉水状态下，有性生殖基本不能进行，种群以微弱的营养繁殖保存。

The three water-depth niches in which Ranalisma rostratum stapf population grown were mimicked, they were called wet, emergent and submerged. The results showed that there was a great increase in plant height, root system length, internode length of pseudo-stolons, number of ramets per clone, fecundity and total mean biomass per clone for R rostratum population, in emergent compared with in wet and submerged, . In wet and emergent, sexual reproduction and vegetative reproduction both could arise normally, but the former tended to be the major in wet. In submerged, the population survived only depanding on very weak vegetative reproduction, and the sexual reproduction could hardly appear. Above all, emergent was the ideal water niche of R rostratum population.