四川地区杉木及其伴生阔叶树种生态适应性研究

Ecological Adaptability of Cunninghamia lanceolata and Accompanied Broad-leaved Tree Species in Sichuan

研究杉木人工林分中杉木与伴生阔叶树种的种间生态关系,探索适宜杉木伴生的阔叶树种,从生态位角度为杉阔混交林改造经营提供依据。采用样线样方相结合的方式对邛崃、洪雅、叙永等地的杉木人工林开展群落学调查,以不同的典型样地为资源位,运用Levins和Shannon生态位宽度指数、生态位重叠指数、生态位相似性比例指数,分别测定并分析杉木与伴生阔叶树种的种间生态位特征。结果表明:以树种重要值大于1为标准,从45个伴生树种中筛选出主要伴生阔叶树种18种;Levins和Shannon生态位宽度指数反映情况一致;木姜子、野梧桐、异叶榕、盐肤木、檫木、灯台树、亮叶桦、山茶、细齿叶柃等9个树种是杉木最重要的伴生阔叶树种,其B(sw)>0.6且B(L)>0.3,它们具有生态位宽度值和重要值都很大,生态适应能力强等特点;杉木主要伴生阔叶树种间生态位重叠程度不高,杉木与主要伴生阔叶树种的生态位重叠值较高(Lih>0.05);杉木与木姜子、亮叶桦、野梧桐、异叶榕、盐肤木、檫木等伴生阔叶树种的生态位相似性比例指数较高(Cih>0.4),说明杉木与这些树种在生境需求上有一定相似性,对资源有共享关系;主要伴生阔叶树种中,落叶树种较常绿树种具有较大的生态位宽度、生态位重叠值和生态位相似性比例,说明培育杉阔混交林应多选择落叶树种作为伴生树种。

The interspecific ecological relationship between Cunninghamia lanceolata(Cl)and accompanied broadleaved trees in Cl plantation was studied to explore the suitable broad-leaved trees accompanied with Cl,and to provide basis for the reconstruction and management of mixed forest of Cl and broad-leaved species from the perspective of ecological niche.A community survey of Chinese fir plantations in Qionglai,Hongya and Xuyong was carried out by the combination method of sample line and sample quadrat.The Levins and Shaanon niche breadth index,niche overlap index,Schoener niche similarity index were used to study and analyze the niche characteristics of the Cl and accompanied broad-leaved trees respectively,with different typical sampled plots as the resource sites.The results showed that:18 species were selected from the 45 accompanied tree species according to the criterion that the important value of tree species was greater than 1.And the Levins and Shaanon niche breadth index reflected the same result.Nine tree species such as Litsea pungens,Mallotus japonicus,Ficus heteromorpha,Rhus chinensis,Sassafras tzumu,Cornus controversa,Betula luminifera,Camellia japonica and Eurya nitida Korthals were the most important accompanied broad-leaved species of Cl,and their important value was B(sw)>0.6 and B(L)>0.3).Their niche breadth and important values were both large and had strong ecological adaptability.The niche overlap between the main accompanied broad-leaved species of Cl was not high,and the niche overlap between Cl and the main accompanied broad-leaved trees was high(Lih>0.05).The Schoener niche similarity index between Cl and Litsea pungens,Mallotus japonicus,Ficus heteromorpha,Rhus chinensis,Sassafras tzumu was high(Cih>0.4),which indicated that Cl and these species had certain similarity in habitat requirements and shared the resources.Among the main accompanied broadleaved tree species,deciduous tree species had larger niche breadth,niche overlap index and Schoener niche similarity than evergreen tree species,which indicated that deciduous broad-leaved tree should be more selected as the accompanied tree species for the cultivation of mixed Cl and broad-leaved forest.