甘肃莲花山植物群落物种多样性对海拔梯度的响应

植物群落的物种多样性与海拔梯度的关系是植物生态学的研究热点。通过对甘肃莲花山自然保护区森林植物群落样地调查，计算乔木层、灌木层和草本层的多样性指数、丰富度指数和均匀度指数，分析森林植物群落物种多样性与海拔的之间的相关性，以此来探讨山地植物群落的变化对海拔梯度的响应，为山地植被的垂直地带性分布提供物种多样性分析的依据。通过分析得出，甘肃莲花山植物群落乔木层的丰富度指数较小，而灌木层的多样性指数较大，乔木层和草本层的均匀度指数在群落间变异幅度较大，而灌木层变异较小。在中海拔地区白桦、红桦和糙皮桦群落的针阔叶混交林中乔木层的丰富度指数、灌木层的多样性指数大于其他海拔地区。在低海拔地区乔木层、灌木层的群落物种多样性较高，而草本层的群落物种多样性较低。

Response of Community Species Diversity to Elevation Gradient in the Lianhuashan Nature Reserve

Species richness index,species diversity index and evenness index were used to measure the diversity of forest plant communities occurring in Lianhuashan Nature Reserve.The diversity characteristics of community species were analyzed,the variation of community species diversity along the elevation gradient was studied,and the phases of each index were calculated.The suitability and conformity of each index were tested.The diversity index of shrub layer was higher than those of herb layer and tree layer.The richness index of tree layer was lower than those of shrub layer and herb layer.The evenness index of the tree layer and herb layer varied greatly between the communities,but the shrub layer did not.The species diversity index of coniferous broad-leaved mixed forest at medium altitude area was higher than those in other elevations.