渠堤化城镇河岸带的植被特征及其用地影响

渠堤化是干扰城镇河流的常见建设方式，掌握植物特征及对其产生显著影响的用地因素，对于优化渠化的城镇河岸植被带具有重要意义。采用样带全面调查的方法，对北京段已基本全线渠堤化潮白河河岸带植物进行调查，通过多重比较分析河岸带植物丰富度在不同空间位置的差异，并利用NMDS非约束排序拟合解译的周边缓冲区土地利用数据，探讨对渠堤化河岸带植物丰富度和种类分布产生显著影响的因素。结果表明:1）河岸带植物种类174种（乔、灌、草分别为52、29、90种），以草本为主；2）全线渠堤化城镇河流河岸带植物群落种类及丰富度均存在建成区和非建成区的显著差异，总体植物、乔木和灌木植物丰富度在建成区显著大于非建成区，但入侵植物沿渠堤化河岸带不存在空间位置的差异，入侵可能沿渠堤蔓延；3）周边缓冲区道路、其他不透水地表面积是城镇地区全线渠堤化河岸带植物丰富度的显著正相关影响因子，对主要观赏灌木和乔木种类分布存在积极影响，对原生灌木和草本种类分布存在消极影响，这种分布特征受人工干扰影响。

Effect of Land Use on Channelized Urban Riparian Plant Communities

Channelization is a common construction method disturbing urban rivers.Adequate protection and management of channelized riparian demand an understanding of the vegetation characteristics and an assessment of their influences on land-use factors.In this study,we focused on the Chaobai River that is nearly entirely channelized in Beijing section,and compared the proximal riparian species richness (by ANOVA) and the plant community composition (through NMDS),then explored the driving factors of land-use.There were 174 plants species including 52 arbors,29 shrubs,90 herbs.Significant differences were found in plant community composition and plant species richness between positions of built-up area and non-built-up area.Moreover,the tree and shrub species showed a greater richness in the built-up area riparian due to human interference related to the plant species selection.Furthermore,the surrounding land-use significantly influenced riparian vegetation; the roads and other impervious surfaces were the driving factors that had positive influences on ornamental trees and shrubs but negative influences on herb species richness.Several management measures for different positions of riparian zones in relation to land-use factors and their main effects were proposed.