摘要
根据历史和三峡工程蓄水后近期的水文观测资料,采用非参数Mann-Kendall趋势分析及突变检验法、线性趋势法以及差异T检验法来检测径流量和输沙量的突变。并采用灰色关联分析法对三口洪道径流量和输沙量演化的影响因素及驱动力进行分析。结果表明,长江干流水位变化对三口分流比的影响显著,但干流河道比降变化以及河床冲刷也会导致河道水位流量关系发生调整,从而导致水位变化,间接引起三口分流比变化。三峡工程蓄水后,低水时期分流比减小幅度大于高水时期,当长江干流枝城站流量小于10000 m3/s时,三口洪道分流比将小于5%,三口洪道将几乎成为季节性河流,断流时间大大增加。
We check the sudden changes of region runoff and sediments transportation using non - parameter Mann - Kendall tendency analysis（ M -K method） , sudden- changes verifying method, linear trend way and T -verifying method to diversities based on history data and up - to - date hydrological surveying records after the impoundment of TGP and analyze the influential factors and driving force to water flow and sediments volume of three river - outlets flood channel from Yangtze River to Dongting Lake by grey incidence decision - making method. The results show that the water level changes of main channel impact the distribution to the whole channel discharge of three river- outlets obviously, however, the gradient changes and scouring of river- bed cause the readjust of water level and discharge relationship, which indirectly results in water discharge changes of three river - outlet distribution. After the impoundment of TGP, the decrease extent of flow discharge distribution ratio is larger in lower wa- ter level than that in flood period. When the discharge is less than 10 000 m3/s at the Zhicheng Gauge Station, the discharge dis- tribution ratio will be less than 5% , and the three outlets almost become seasonal rivers with more draught - ups.
出处
《人民长江》
北大核心
2010年第2期38-42,46,共6页
Yangtze River
基金
国家重点基础发展计划[973]资助项目(2003CB415200)
中游局科研专项基金(2007004)
关键词
水沙输
变化分析
三口洪道
洞庭湖
Dongting Lake
three river - outlets flood channels
water and sediments transport
changes
