石羊河中下游河岸植被的结构及其功能研究

Types and Ecological Function of Riparian Vegetation at Middle and Low Reaches of Shiyang River

为了研究石羊河中下游的河岸植被结构和功能对区域生态环境管理和恢复的意义,依径流量将研究区域分为丰水河段和干涸河段,调查距河床不同间距的植被结构与空间分布,进行植被分类和空间格局分析,讨论其功能。石羊河中下游的河岸植被带宽约200～500m,分布区域内植物群落类型的80%以上的建群种,拥有18个群丛。河岸植被类型依河床间距呈梯级分布,河岸植被盖度随河床间距增大成指数下降。河岸植被带不仅拥有乔木和沼泽植物组成的隐域性植被类型,是区域特有种栖息地;而且形成景观廊道,连结斑块,稳定区域生态系统,保护河岸、稳定河床、防治水流和风沙灾害,为当地人们提供多用途的娱乐场所和舒适的生活环境。

The aim was to study the importance of the structure and function of riparian vegetation at middle and low reaches Shiyang River for ecology manager and restoring.The middle and low reaches of Shiyang River were divided into richness runoff and run dry where the structure and space distribution of riparian vegetation at different distance from river bed were investigated,then the types,spatial pattern and function of riparian vegetation were analyzed for management and restoration ecological environment.The results showed：the width of riparian vegetation,which could be classified into 18 associations,was 200-500 m,and the 80% of constructive species of region plant community were fund at riparian place.It was distinct that types of vegetation orderly change with the distance from river bed,as well as decrease in exponent of coverage rate of riparian vegetation.The riparian vegetation not only had special humidogene plants,such as tree and marsh plant,and native plant communities,but also joined the plots of landscape at local area to make up a stable regional ecology system.The belt of riparian vegetation protected riverside and stabilized river bed to control disaster in runoff and sand-wind.The riparian vegetation also gave a basis to defend oasis by breaking the wind and a comfortable environment for local people.