【作者】 陈宁；

【导师】 王刚；

【作者基本信息】 兰州大学 ， 生态学， 2013， 硕士

【摘要】 关于群落构建机制的研究,以前多从物种角度出发,通过研究物种间的相互作用以及环境对该关系的影响等揭示群落构建的机制,这种方法在研究生境中物种数目较少时比较有效,当物种丰富度增加时,基于物种的方法变得十分麻烦而且解释能力和预测能力差。与基于物种的方法不同,基于性状的方法以其量化、简约、系统性和可预测等优点得到了越来越多研究者的认可,在研究群落构建机制中得到了广泛的应用。性状在群落构建的研究中主要表现两个非随机过程：性状收敛与性状分歧模式。性状在生境和互利共生等因素影响下所呈现的性状值范围变小的模式为性状收敛模式,而性状在竞争和干扰等因素的影响下所呈现的性状值之间的距离变大的模式为性状分歧模式。本文以亚高寒草甸群落为研究对象,分别测量直接环境因子(土壤含水量和光照强度)和间接环境因子(坡向和坡度),在不同阴坡-阳坡梯度上选择不同大小的群落,分析其群落构建的规律,影响群落构建机制研究的要素,以及环境因子与群落构建机制研究的关系。主要得到以下三个结论：(1)在研究的49个群落中,只有两个群落的性状收敛模式与零模型的随机群落的性状收敛模式存在显著性差异,而性状分歧模式则全部无显著差异；。(2)尺度的大小以及考虑种内变异与否等因素对研究群落构建机制有比较大的影响。(3)间接环境因子相对于直接环境因子能更有效地捕获该生境下环境因子的信息,以间接环境因子为环境条件比直接环境因子显著性提高了性状收敛模式的检测,而性状分歧模式之间无显著性差异,间接环境因子不失为良好的环境变量。更多还原

【Abstract】 Previous studies about community assembly rule were mostly based on species, which is rather an efficient when the number of species in habitat is two or three. With the escalation of species richness, the method become more and more difficult and the ability of explanation and prediction becomes weak. Different from it, the methods based on traits are gaining recognition by more and more researchers in the study of community assembly rules for its quantitative, simplicity, systematic and predictable. There are two non-random processes in community assembly:trait convergence pattern and trait divergence pattern. The pattern of the range decreases presented by trait in the effect of habitat and mutualism is called trait convergence pattern. On the other hand, the pattern of distances among traits get larger in the influence of competition and disturbance is called trait divergence pattern. In this paper, we take hill community of subalpine as study subject, measuring direct environmental factors-soil moisture, light intensity-and indirect environmental factors-slope, aspect, selecting various sizes of sub-communities in the gradient from south-facing to north-facing slope. The aim is to get the assembly rules of communities, to analyze the factors impacting on the assembly and the relationship between environmental factors and studies of community assembly. Get three conclusions as following:(1)There are only two cases of significant trait convergence assembly pattern in all communities and none for trait divergence assembly pattern.(2)The selection of statistical methods and traits, null model, scale and intraspecific variation have relative important influence on community assembly.(3)Relative to direct environmental factors, indirect ones are efficient in presenting the information of environment. Taking indirect environmental factors as environmental condition relative to direct ones significantly improved the detection of TCAP, and there is no different for TDAP.更多还原