摘要
介绍了河流潜流带的含义,即是河水与地下水发生物质能量交换的区域,其水力联系和交换水量大小受河床沉积物渗透系数的影响。对近年来国内外学者对河床潜流带渗透系数变化进行了大量研究。由于特殊的环境与水文地质条件,潜流带渗透系数的大小不仅取决于沉积物孔隙大小和孔隙的连通性,而且与生物扰动、河流流水等作用紧密相关:洪水带来的细小颗粒引起河床表面沉积物孔隙淤塞,致使渗透系数减小,但在洪水退后,潜流带的水文交换和生物扰动能破坏淤塞层,从而引起反淤塞作用,造成河床渗透系数增大。因此,淤塞-反淤塞作用改变着河床的渗透性能。最后,指出存在的问题今后的研究方向。
The hyporheic zone plays a key role in the surface water and groundwater interaction. Streambed hydraulic conductivity can af- fect the magnitude of interactions between groundwater and surface water and hyporheie water exchange. The clogging and declogging processes often occur alternately, which can change the streambed sediment characteristics and affect its permeability. On the ba- sis of the overview of literatures of hyporheic exchange and streambed hydraulic conductivity, the possible effects of clogging and declogging processes on the streambed hydraulic conductivity have been illustrated. Streambed hydraulic conductivity is not only affected by the pore size of sediments, hut also related to the hydrological connectivity and hioturhation in the hyporheic zone. Generally, the small particles brought by the floods can cause riverbed clogging, resulting in reduced hydraulic conductivi- ty. However,when the flood goes down, hydrological exchange and bioturbation in the hyporheic zone can destroy the clogging layer,causing the declogging process and increasing in hydraulic conductivity. The current studies are limited to the analysis of the variations of measured streambed hydraulic conductivity data, and the mechanism of the clogging and declogging processes in the hyporheic zone of a river requires more investigations. At last,it is pointed out that the existing problems in the future.
出处
《南水北调与水利科技》
CAS
CSCD
北大核心
2013年第3期123-126,共4页
South-to-North Water Transfers and Water Science & Technology
基金
国家自然科学基金(51079123)
教育部新世纪优秀人才支持计划项目(NCET-11-1045)
教育部留学科研启动基金(教外司留[2010]1174)
关键词
河流
地表水-地下水
潜流带
水文交换
生物扰动
淤塞-反淤塞
渗透系数
stream
surface water and groundwater
hyporheic zone
hydrological exchange
bioturbation
clogging-deelogging
hy- draulic conductivity
