赤水河黔西北段植物群落物种多样性特征

Species diversity characteristics of forest community in northwestern Guizhou section of Chishui river

为促进赤水河流域上游黔西北段植被恢复和生物多样性保护,设立35个森林群落样地,采取样方调查方法,对植物群落物种多样性进行统计分析,采用去趋势典范对应分析(detrended canonical correspondence analysis,DCCA)排序法,分析群落与环境因子的关系。结果表明:赤水河上游黔西北段样地中,共调查到79科183属262种物种,植物组成丰富。不同植物群落乔木层、灌木层、草本层的多样性指数差异较大,以灌木层的多样性指数变化最小。银白杨( Populus alba )和亮叶桦( Betula luminifera )为优势树种的林分具有更为复杂的结构,但优势树种分布亦趋于集中。经度、纬度和海拔对样地分布的影响效应较强,坡位、坡向对群落分布的影响效应较弱,坡度越低则群落组成越丰富。研究区群落多样性受到丰富度在内的诸多因子影响,因此建议对该区森林群落进行综合管理和科学经营。

In order to promote vegetation restoration and biodiversity conservation in the upper reaches of Chishui River basin in northwestern Guizhou section,35 sample plots of forest community were set up,and sample survey methods were used to statistically analyze plant species diversity,using detrended canonical correspondence analysis (DCCA) ranking method to analyze the relationship between community and environmental factors.The result indicated that 262 species of 183 genera and 79 families were found in total in the upper reaches of Chishui River basin in northwestern Guizhou part,which were diversified composition.The diversity indexes of tree layer,shrub layer and herb layer in different plant communities were significantly different,presenting the smallest change in shrub layer.Forest stand with Populus alba and Betula luminifera as dominant tree species had more complex structure,while considering the distribution of dominant tree species also tended to concentrated.The effect of longitude,latitude and altitude on the distribution of sample plots was strong,but the impact of slope position and slope direction on community distribution was weak.The lower the slope was,the richer the community composition would be.The community diversity of sample plots were influenced by several factors including richness.Therefore,it is suggested to use comprehensive and scientific manner of the forest community in the study area.