大黄花虾脊兰生境特征及生存群落物种生态位分析

Habitat characteristics and niche analysis of Calanthe sieboldii Decne. survival community

大黄花虾脊兰(Calanthe sieboldii Decne.)已被列入《全国极小种群野生植物拯救保护工程规划》,是亟待拯救的极小种群物种之一。为弄明其生境特征及生存群落中的种间关系,对分布于安徽泾县的大黄花虾脊兰进行全面调查,以18个样地内22个样方数据为基础,应用Levins和Hurlbert生态位宽度公式和生态位重叠公式,对其生存群落内草本层主要物种的生态位及其生境特征进行了研究。结果表明:(1)大黄花虾脊兰分布于泾县桃岭村地带,呈聚集分布,主要分布于靠近河边的陡崖下,分布地点较为空旷,且没有强光直射。(2)在大黄花虾脊兰生存小群落内,其优势地位明显,草本层主要物种之间普遍存在生态位重叠,但重叠程度较低,物种之间竞争并不强烈,资源可以较充分共享,群落草本层处于稳定状态。

Calanthe sieboldii Decne. is included in the National Implementation Plan for Rescuing and Conserving China＇s Plant Species with Extremely Small Populations（ PSESP）,highlighting the urgent need for its rescue. To determine the habitat characteristics of C.sieboldii and the interspecific relationships among species within the C. sieboldii community,we conducted a comprehensive investigation of C. sieboldii distributed in Jingxian County of Anhui Province,China. Based on data from 22 quadrats in 18 sample plots,we analyzed the habitat conditions of the C. sieboldii community,and analyzed the niche characteristics of the main herbaceous species in the community using Levins＇ and Hurlbert＇s formulae for niche breadth and the similarity ratio of resources used for niche overlap. Results showed that：（ 1） C. sieboldii exhibited scattered distribution in Taoling village of Jingxian County,with most plants found in relatively open areas under steep cliffs near rivers with no direct sunlight;（ 2）C. sieboldii had an obvious advantage in the herb layer of the community. Niche overlaps existed among the main species in the herb layer,but the degree of overlap was low,interspecific competition was not intense,and environmental resources could be sufficiently shared by different species. The herb layer in the community was in a relatively stablecondition.