千岛湖马尾松林分改造中主要树种生态位动态研究

Study on the Ecological Niche Dynamics of the Major Tree Species in the Transformation of Pinus massoniana Forest Stand in Thousand-isle Lake

基于千岛湖马尾松次生林抚育疏伐并补植改造前及第3年、第14年的3次调查监测,分析了千岛湖马尾松次生林5个改造样地林分的主要种群重要值变化及其生态宽度、生态位相似性比例和生态重叠指数。结果表明:马尾松疏伐改造后补植木荷、枫香,马尾松在种群中的重要值不断上升,林分改造后的重要值除马尾松外,其次为檵木、木荷和刺柏。千岛湖林分改造之后的泛化种优势明显,生态位宽度在0.5以上的是马尾松、枫香、檵木、刺柏、石栎和木荷。千岛湖生态位宽度高的物种,生态位相似性比例一般较高,主要种群生态位重叠值大于0.4的在千岛湖林分改造前后均大于50%,形成了马尾松等常绿针叶树种与常绿、落叶阔叶树种、灌木树种的共生与竞争不断向正向演替发展的生境。

Based on three surveys and monitoring before tending,thinning,and replanting of Pinus massoniana secondary forest in Thousand-isle Lake,as well as in the 3rd and 14th years,this study analyzed the changes in the main population importance values,ecological width,niche similarity ratio,and ecological overlap index of five transformed plots of Pinus massoniana secondary forest in Thousand-isle Lake.The results showed that the importance values of adding Schima superba and Liquidambar formosana to the population after thinning and transformation of Pinus massoniana were continuously increasing.After stand transformation,the importance values of Loropetalum chinense,Schima superba,and Juniperus formosana were the second highest,except for Pinus massoniana.After the transformation of the Thousand-isle Lake forest stand,the advantages of generalization species were obvious.The niche width of Pinus massoniana,Liquidambar formosana,Loropetalum chinense,Juniperus rigida,Lithocarpus glaber and Schima superba were more than 0.5.Species with high niche width in Thousand-isle Lake generally had a higher proportion of niche similarity.The main populations with niche overlap values greater than 0.4 were more than 50%before and after forest stand transformation in Thousand-isle Lake,forming a habitat where the symbiosis and competition among evergreen coniferous tree species such as Pinus massoniana,evergreen and deciduous broad-leaved tree species,and shrub species continued to develop towards positive succession.