长喙毛茛泽泻的种群分布格局和群落内种间关联

THE SPATIAL PATTERN OF RANALISMA ROSTRATUM POPULATION AND INTERSPECIFIC ASSOCIATION IN THE COMMUNITY

长喙毛茛泽泻茶陵种群呈斑块分布，格局类型为聚集分布型，每个亚种群也呈聚集分布，但聚集强度不同。长喙毛茛泽泻与其几个主要伴生种的相关性经测定结果是：与莼菜及黄花狸藻之间的相关性不显著；与柳叶箬、双穗雀稗及石龙尾之间正相关显著；与疏勿蓼之间负相关显著，长喙毛茛泽泻种子近距离传播以及无性繁殖特性是造成其聚集分布的主要原因。柳叶箬、双穗雀稗和石龙尾对长喙毛茛泽泻具有极强的竞争作用。

In Chaling county,the natural population and four sub populations showed a spotted and aggregated distribution pattern,but their degrees of aggregation were different.While Ranalisma rostratum had no association with Brasenia schreberi,Utricularia aurea, it had a great positive association with Isachne globosa,Paspalum distichum,Limnophila sessilifla and a great negative association with Polygonum praeterissum. The aggregated distribution was mainly caused by its poor seed dispersal and clonal growth.There was a competition among R.rostrratum,I.globosa,P.distichum and L.sessiliflora.