长江口九段沙典型潮沟植物群落的物种多样性和种群生态位

在九段沙湿地自然保护区典型潮沟区域设立了52个样点，计测了样点内植物的生态重要值和土壤湿度、电导率和水电导率。在此基础上，计算了样点的物种多样性指数、每种植物的生态位宽度和种间生态位重叠关系，生成了基于生态位重叠值的主坐标排序图和最小生成树。结果发现，九段沙保护区已有高等植物48种，其中31种为首次报道；48种高等植物中，双子叶植物23种，单子叶植物21种，苔藓植物4种；九段沙植物以温带成分为主，其次为世界分布类型，热带性成分较少。52个样点共出现22种植物，样点的物种多样性指数差异明显。基于生态位重叠值的主坐标排序，可以识别出6组生态类群。在调查区域，植物种类组成中有较高比例的杂草和入侵植物，反映出研究区域已受到人为干扰的强烈影响。

SPECIES DIVERSITY AND POPULATION NICHE OF PLANTCOMMUNITY WITHIN TYPICAL TIDAL CREEK OF JIUDUANSHANATURE RESERVE IN THE YANGTZE RIVER ESTUARY

52 sites were set up within typical tidal creek of Jiuduansha Nature Reserve.The ecological importance value of plant,soil moisture ,soil conductivity and water conductivity in 52 sites were measured.We figured out species diversity index,individual specie niche breadth and overlap between each other,then generated principal coordinates diagram and minimum spanning tree.The results showed 48 species in Jiuduansha Nature Reserve,belonging to 4 bryophytes,21 unicotyledon and 23 bicotyledon,of which 31 species were first reported.According to plant geographical distribution,components are most in temperate,then in world wide and less in tropical least.22 species were found in 52 sites,in which diversity index were significantly different.It can be identified six ecological groups on principal coordinates diagram with niche overlap.We conclude that Jiuduansha Nature Reserve has been interfered by the human activities and more weeds and invasive plants develop in sites.〖