甘南高寒草甸坡向梯度对植物群落功能多样性的影响

植物群落功能多样性对于维持生态系统功能具有十分重要的意义。该研究以青藏高原高寒草甸植物群落为研究对象，运用R软件程序包(FD、Vegan)与单因素方差分析法，分析高寒草甸不同坡向植物群落功能多样性的变化及其与环境因子的关系，以揭示微生境梯度上植物对环境的适应策略以及群落种间功能特征及生态系统内部结构和功能的变化机制。结果显示：(1)青藏高原高寒草甸的北坡和西北坡的物种丰富度、植物株高、比叶面积、叶片有机碳、叶片氮以及叶片磷显著高于其他坡向，且坡向间差异显著(P<0.05)。(2)在北坡到南坡的变化中，功能丰富度差异比较明显(P<0.05)，株高、比叶面积、叶片有机碳、叶片氮及叶片磷等功能丰富度均呈递减趋势。(3)北坡的株高功能均匀度、西北坡比叶面积、叶片有机碳、叶片氮及叶片磷等功能均匀度均显著高于南坡，且多元性状功能均匀度在坡向间差异显著(P<0.05)。(4)北坡的比叶面积、叶片氮功能离散度及西北坡的株高、叶片有机碳、叶片磷等功能离散度均高于南坡，且坡向间差异显著(P<0.05)。(5)植物群落功能多样性与土壤含水量、土壤有机碳、土壤全氮、土壤全磷呈显著正相关关系(P<0.05)，与坡度、土壤pH、土温、照度呈显著负相关关系(P<0.05)。

Effect of Slope Aspect Gradients on Functional Diversity of Plant Community in Alpine Meadow of Gannan

The functional diversity of plant communities is very important for maintaining ecosystem functions. In this test, R software package (FD, vegan) and single factor analysis of variance (ANOVA) were used to analyze the relationship between functional diversity and environmental factors of alpine meadow communities in different slope directions, so as to reveal the adaptation strategies of plants to the environment, the functional characteristics of community species and the change mechanism of internal structure and function of ecosystem on microhabitat gradient. The results showed that: (1) the species richness, plant height, specific leaf area, leaf organic carbon, leaf nitrogen and leaf phosphorus in the north and northwest slopes were significantly higher than those in other slopes of the alpine meadow in the Qinghai Tibet Plateau, and the differences were significant (P < 0.05). (2) The difference of functional richness was obvious (P < 0.05), plant height, specific leaf area, leaf organic carbon, leaf nitrogen and leaf phosphorus showed a decreasing trend from north to south slopes. (3) The functional evenness of plant height, specific leaf area, leaf organic carbon, leaf nitrogen and leaf phosphorus in north slope were significantly higher than those in south slope, and the functional uniformity of multiple traits was significantly different between different slopes (P < 0.05). (4) The specific leaf area, leaf nitrogen function dispersion of north slope and plant height, leaf organic carbon and leaf phosphorus functional dispersion of northwest slope were higher than those of south slope, and the difference between slopes was significant (P < 0.05). (5) Plant community functional diversity was positively correlated with soil water content, soil organic carbon, soil total nitrogen and soil total phosphorus (P < 0.05), and negatively correlated with declivity, soil pH, soil temperature and illumination (P < 0.05).