甘肃祁连山国家自然保护区植物群落分布格局及其与环境因子的关系

Distribution pattern of plant community and its relationship with environmental factors in Qilian Mountains National Nature Reserve of Gansu Province

植物群落分布格局是环境因子和人类活动共同作用的结果,尤其是海拔梯度被认为是植物群落分布格局的决定性因子,为探求甘肃祁连山国家自然保护区植物群落分布格局与环境因子的关系及其驱动机制,该文在野外调查的基础上,运用数量分类和除趋势典范对应分析(DCCA)排序等方法,探讨了研究区内植物群落特征及其与环境因子的关系。结果表明:(1)88个样方共记录物种85种,隶属30科56属,利用双向指示种分析法(TWINSPAN)将其分为9个植物群落。(2)9个植物群落在DCCA排序图上聚集分布,呈现出较好的环境梯度,其中海拔对植物群落分布格局影响最大,其次为降水、温度、坡度、坡向和土壤腐殖质。(3)影响植物群落空间分布格局的变量中,环境因子占25.24%,空间因子占13.21%,空间因子和环境因子交叉作用占9.03%,群落分布格局未被空间因子和环境因子解释部分占52.52%,这部分主要反映了人类活动对研究区植物群落分布格局的影响。该研究成果对区域内植被的生态恢复和生物多样性的稳定维持具有重要意义。

The distribution pattern of plant community is the result of the interaction of environmental factors and human activities,especially the elevation gradient is considered as the decisive factor of the distribution pattern of plant community.In order to explore the relationship between plant community distribution pattern and environmental factors and its driving mechanism in Qilian Mountains National Nature Reserve of Gansu Province,the characteristics of plant community and its relationship with environmental factors in the study area were disucssed,using quantitative classification and DCCA sequencing methods on the basis of field investigation.The results were as follows:(1)There were 85 species of seed plants belonging to 30 families and 56 genera in 88 sampling plots of Qilian Mountains National Nature Reserve of Gansu Province,including twelve species of Gramineae,nine species of Compositae,eight species of Fabaceae,six species of Rosaceae and five species of Chenopodiaceae,accounting for 14.11%,10.59%,9.41%,7.06%and 5.88%of total species,respectively.These plants could be classified into nine plant communities throught TWINSPAN.(2)Nine plant communities were clustered and distributed on the DCCA sequencing diagram,showing a good environmental gradient.Altitude had a great influence on the distribution pattern of plant communities,followed by precipitation,temperature,slope,slope direction and soil humus.(3)Among the variables influencing plant community spatial distribution pattern,environmental factors accounted for 25.24%,spatial factors accounted for 13.21%,space factor and environment factor interactions accounted for 9.03%,52.52%of the community distribution pattern was not accounted by spatial factor and environmental factor section,and this part mainly reflected the human activity influence on plant community distribution pattern in the study area.The results of this paper are of great significance to the ecological restoration of vegetation and the stable maintenance of biodiversity in the region.