【摘要】 物种多样性对海拔梯度的响应是植物生态学研究领域的热点。为探究温带半干旱-半湿润过渡地带山区物种多样性沿海拔梯度的分布规律,以吕梁山脉北段饮马池山为研究对象,通过野外群落调查,分析了饮马池山阳坡植物群落α多样性和β多样性对海拔梯度的响应。结果表明:在海拔梯度上,样地内共调查物种29科69属97种,群落物种组成具有明显的温带性质;从低海拔到高海拔植被依次分布有山前山地草原(1 710-1 915 m)、山地灌丛草原(1 915-2 110 m)、山顶亚高寒草甸(2 110-2 200m),灌草丛群落主要分布在1 900-2 100m。植物群落草本层α多样性大于灌木层,随着海拔的升高,植物群落物种丰富度呈"M"型变化趋势,在1915m和2110m处最大;灌木层α多样性指数呈单峰型变化趋势,在2 060m处最大;草本层α多样性指数呈波动变化趋势,α多样性指数在1 900-2 100m处呈下降趋势。Sorensen指数在海拔1 860-1 915 m和2 110-2 153 m之间出现两个最小值,而Cody指数出现两个峰值,表明该海拔地段β多样性最大,样地群落间相似性低,成为物种更替速率较快的过渡地带。在温带山区,以β多样性为指标测量群落间或生境间环境梯度变化较为可行,海拔变化对山地植物群落物种多样性差异产生直接或间接的影响,这对管理和恢复温带山地植被以及维持生态系统稳定具有重要指导意义。更多还原

【Abstract】 The response of species diversity to the altitude gradient has become a hot issue in plant ecology. In order to explore the altitudinal patterns of diversity characteristics of plant communities in semi-arid and semi-humid transition region, we analyzed the characteristics of plant community α and β diversity based on field investigations along the sunny slope of Yinmachi Mountain in Luliang Mountains, at approximately 50 m intervals. The results showed that the plants in this study areas belonged to 29 families, 69 genera and 97 species, with obviously temperate nature. Along altitude gradient, the vegetation types, mainly composed of mountain steppe(1 710-1 915 m), mountain shrub steppe(1 915-2 110 m) and subalpine meadow(2 110-2 200 m), the shrub-grass community structure ranged from 1 900 to 2 100 m. The species diversity of herb layers were higher than shrub layers, in general, the species richness of plant community formed a "M" pattern with increasing elevation, peaking at the altitude of 1 915 m and 2 110 m; the herb-layer of α diversity showed a unimodal pattern, peaking at the altitudes of 2 060 m; the shrub-layer of α diversity showed a fluctuation trend, and the herb layers showed a downward trend at 1 900-2 100 m. The Sorensen index reached minimum in the altitude of 1 860-1 915 m and 2 110-2 153 m, but Cody index reached two peaks, it was suggested that the β diversity of those elevations were the largest, and the similarity between the communities was low, which were transitional zones. We conclude that theβ diversity index is more applicable to measure the environmental gradients between communities or habitats as an indicator and altitude as a main driving factor has a direct or indirect impact on the species diversity of mountain plant community. These results are important for the management and restoration of temperate mountain vegetation and the maintenance of ecosystem stability.更多还原