摘要
在三峡大坝下游的湖北宜都关洲设立1个40 m×40 m的固定样地,利用高度分级,比较2008与2009年两年间的疏花水柏枝(Myricaria laxiflora)种群数量动态,并运用点格局的Ripley's K函数分析了其空间格局变化及种群更新特征。结果表明,疏花水柏枝幼苗数量较少,种群更新存在一些障碍。空间分布格局与空间尺度及植株的大小密切相关。种群总体呈集群分布,各大小级多在9 m时出现最大的聚集强度,随着大小级的增加,聚集强度有减弱的趋势。幼苗与中株有较强的正关联。由于种群现有生境变化较大,应考虑迁地保护,并对原生种群加强长期动态监测;同时,开展疏花水柏枝适应机理研究,实施科学保护。
Myricaria laxiflora is an endangered shrub distributed around the Three Gorges Reservoir.To understand the impacts of the Three Gorges Dam on population dynamics and spatial pattern of remanent M.laxiflora,a permanent 40 m×40 m plot was established on a sandbar downstream from the dam.We analyzed the spatial pattern and population dynamics of M.laxiflora between 2008 and 2009 using univariate and bivariate Ripley＇s K function.Our results demonstrated that M.laxiflora population regeneration was impacted,particularly in regards to small number of seedlings.The spatial pattern of M.laxiflora was significantly cor-related with spatial scales and individual size.Myricaria laxiflora was aggregated at most scales from 2 m to 20 m,with highest aggregation intensity at 9 m.With size increase,the aggregation intensity tended to decline.Population recruitment relied on the middle-sized individuals.We proposed that ex-situ conservation should be considered for M.laxiflora,and its population dynamics in natural habitats should be monitored over the long term.
出处
《武汉植物学研究》
CSCD
北大核心
2010年第6期711-717,共7页
Journal of Wuhan Botanical Research
基金
中国科学院院地合作局资助项目
中国科学院知识创新工程领域前沿项目(54O754501J0447)~~
关键词
疏花水柏枝
河岸带
种群动态
点格局分析
空间关联
Myricaria laxiflora
Riparian zone
Population dynamics
Point pattern analysis
Spatial association
