高寒草甸不同坡向植物群落物种多样性与功能多样性的关系

植物群落物种多样性与功能多样性是生态学研究的热点问题之一，研究其对于保护生物多样性和维持生态系统功能具有重要意义。采用野外群落调查方法，探讨了物种多样性与功能多样性在坡向梯度上的变化格局及其关联性。结果显示：（1）从北坡到南坡，土壤含水量、有机碳呈递减趋势；坡度、照度、土温、pH呈递增趋势；土壤全氮、全磷在西坡明显低于其他各坡向；（2）物种多样性指数均由北坡向南坡依次递减；（3）一元性状功能多样性在各坡向间的差异显著（P<0.05），除LDMC_FDrao外，其他功能性状均为北坡大于南坡；（4）多元性状功能丰富度与功能均匀度均由北坡向南坡呈递减的趋势，各坡向的功能均匀度差异性不显著。通过相关分析与通径分析发现，功能多样性指数的主要环境决定因子与限定因子均存在差异：功能丰富度、功能均匀度主要环境限定因子为pH，功能离散度主要环境限定因子为土温；功能离散度主要环境决定因子为土壤含水量；（5）物种多样性指数与功能丰富度呈正线性相关，与功能离散度呈负线性相关，而与功能均匀度不相关。

Relationship between species diversity and functional diversity of plant communities on different slopes in alpine meadow

Community species diversity and functional diversity is one of the hot topics in ecological research, and it is great significance to protect biodiversity and maintain ecosystem functions. In this study, the change and relationship of species diversity and functional diversity in different slope aspects of alpine meadow were discussed by field community survey, R software package (FD, vegan) and single factor analysis of variance (ANOVA), so as to reveal the adaptation strategies of plants to the environment, the functional characteristics of community species and the change mechanism on microhabitat gradient. The results showed that:(1) from north to south slope, the soil water content (SWC) and soil organic carbon (SOC) presented a decreasing trend; the slope gradient (SG), illumination (LI), soil temperature (ST), and pH were increasing; the soil total nitrogen (STN) and total phosphorus (STP) were significantly lower on the west slope than those on other slope. (2) The species diversity index decreased from north to south slope. (3) Plant single-trait functional diversities were significantly different on slope (P<0.05). The PH_FDrao, LWC_FDrao, SLA_FDrao, LCC_FDrao, LNC_FDrao, LPC_FDrao, LKC_FDrao on the north slope were higher than those on the south slope, except LDWC_FDrao. (4) The functional richness (FRic) and functional dispersion (FDis) of multiple-traits decreased gradually along the slope aspect gradients, and there was no significant difference in functional evenness (FEve) between slope aspects. Correlation analysis and path analysis showed that the main environmental determinants and limiting factors of functional diversity index (functional richness, functional evenness, and functional dispersion) were different. pH was the main environmental limiting factor of functional richness and functional evenness; soil temperature was the main environmental limiting factor of functional dispersion; and the main environmental determinant of functional dispersion was soil water content. (5) The species diversity indices had positive linear correlation with functional richness, negative linear correlation with functional dispersion, but not with functional uniformity. The relationships between species diversity and functional diversity and their response to environmental changes determine the community ecosystem function.At the same time, it can be better to understand coexistence mechanism of species, and the relationship between biodiversity protection and ecosystem functions and processes is of great significance.