| 摘要: |
| 通过对3次水文泥沙测验资料的整理，分析了椒江河口含沙量在纵向、垂向的空间分布和随季节变化、潮汛变化、涨落潮变化等时间分布特征；依据径、潮流相对强弱的不同，将椒江河口分为3个区段来讨论。研究表明：①径、潮流通过对河床的冲刷和对泥沙的输运来实现对含沙量时空分布的影响。②径流控制的河段含沙量垂向变化梯度大于潮流控制的河段。不同区段含沙量峰值出现时刻具有显著差异，含沙量变化周期大致有两种，分别约为6和12 h。造成各区段差异的原因主要与水流输沙方向，水力活跃度和沙源供给有关。③径流量增大能显著提高灵江河床冲刷速率，且对含沙量起到“稀释”作用。④洪水将严重破坏含沙量分布的规律性，各区段含沙量明显降低且持续时间较长。 |
| 关键词: 椒江河口 径流 潮流 含沙量 时空分布 |
| DOI： |
| 分类号:TV148 |
| 基金项目:国家自然科学基金资助项目（51409163）；水利部公益性行业科研专项（201201070）；交通运输部重大科技专项（201132874640） |
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| Influences of variations in runoff and tide on spatial and temporal distribution of sediment concentration in Jiaojiang River estuary |
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XIA Wei-yi, ZHAO Xiao-dong, ZHANG Xin-zhou
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Key Laboratory of Port, Waterway and Sedimentation Engineering of the Ministry of Transport, Nanjing Hydraulic Research Institute, Nanjing
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| Abstract: |
| According to the field observation data concerning the Jiaojiang River estuary, the characteristics of the spatial distributions of longitudinal and vertical directions and the temporal distributions of the seasons and tide are analyzed in this study. Based on the relative strength between the runoff and tidal current, the Jiaojiang River estuary is divided into three segments. The analysis results indicate that: (1) The influences on the spatial and temporal distribution of the sediment concentration is given by the runoff and tide scouring the riverbed and transporting the sediment; (2) The vertical gradient of the sediment concentration is larger in the segment controlled mainly by the runoff than that in which controlled by the tidal current. There are significant differences among the moments of the peak sediment concentration in the different segments. The change periods of the sediment concentration are about 6 hours or 12 hours. The differences between three segments are mainly caused by the main direction of sediment transportation, the hydraulic activity and the sediment sources; (3) The increasing runoff discharge can raise the riverbed erosion rate and make dilution of effects on the sediment concentration; (4) The flood can break the rules of the sediment distribution and reduce the sediment concentration severely for a long time. The analysis results would be of important scientific values revealing the sediment movement rules in the estuaries and be of realistic significance for estuary regulation and resource utilization. |
| Key words: Jiaojiang River estuary runoff tide sediment concentration spatial and temporal distribution |
