【摘 要】
:
河流入海泥沙是河口三角洲长期演变的物质基础.河口浅滩是河口三角洲典型的地貌现象,对河口三角洲演变具有重要的指标意义.近30年来长江入海泥沙锐减,三角洲沉积环境发生显著变化.基于长江河口典型浅滩断面的综合调查成果,研究长江泥沙减少背景下河口典型浅滩断面泥沙输移特性和机制.研究结果表明:河流入海泥沙主要向东扩散和向南沿岸输运,东西方向2 m和5 m等深线出现表层和底层净输沙分异现象;余流空间分布控制泥沙净输运趋势,水体高含沙量对泥沙净输移作用显著.北侧浅滩断面水下斜坡已处于略有冲刷状态,南侧受到北侧沿岸输沙补
【机 构】
:
华东师范大学河口海岸学国家重点实验室,上海200241
论文部分内容阅读
河流入海泥沙是河口三角洲长期演变的物质基础.河口浅滩是河口三角洲典型的地貌现象,对河口三角洲演变具有重要的指标意义.近30年来长江入海泥沙锐减,三角洲沉积环境发生显著变化.基于长江河口典型浅滩断面的综合调查成果,研究长江泥沙减少背景下河口典型浅滩断面泥沙输移特性和机制.研究结果表明:河流入海泥沙主要向东扩散和向南沿岸输运,东西方向2 m和5 m等深线出现表层和底层净输沙分异现象;余流空间分布控制泥沙净输运趋势,水体高含沙量对泥沙净输移作用显著.北侧浅滩断面水下斜坡已处于略有冲刷状态,南侧受到北侧沿岸输沙补给减少的影响,淤积速率放缓.
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