【作者】 刘勇胜；

【导师】 陈沈良；

【作者基本信息】 华东师范大学 ， 自然地理学， 2006， 硕士

【摘要】 河流入海水沙通量是地球科学国际前沿课题，是国际地圈一生物圈计划(IGBP)的两个核心计划——全球海洋通量联合研究(JGOFS)和海岸带陆海相互作用(LOICZ)的中心议题，它对全球变化研究具有重要意义。黄河作为世界上著名的多沙河流，过去平均每年将12亿t悬移质泥沙输送入海，占全世界河流年入海悬移质泥沙180～240亿t的5％以上，在全球泥沙循环中具有重要作用。 过去黄河入海沙量巨大，使得黄河三角洲快速淤涨，近50年来黄河入海沙量持续递减，导致黄河三角洲自1996年开始出现整体蚀退趋势，尤其是1976年黄河改道清水沟流路以后，飞雁滩海域和孤东海域侵蚀严重。本论文利用利津水文站1950～2003年的水沙资料和1976～2002年黄河三角洲滨海区36个断面的地形实测资料，采用水文学、泥沙运动力学、统计分析和地理信息系统相结合的方法，以及动力、沉积、地貌相结合的思想，在探讨黄河入海水沙通量变化规律与三角洲演变规律的基础上，探讨了三角洲演变与入海水沙的关系，力求为入海水沙的合理利用，三角洲侵蚀防护提供决策依据和理论根据。 通过对黄河入海水沙通量的年代变化、年际变化、季节变化以及水、沙通量之间关系的研究，结果表明：黄河入海水、沙通量递减趋势明显，尤其在近20a来这种趋势更加显著；年际、年内沙量变化幅度都大于水量；黄河入海水沙主要集中在汛期，汛期与非汛期的水沙量差异将会持续减小：年输沙量和年径流量、多年平均月输沙量和径流量分别以乘幂、多项式回归，各月多年输沙量和径流量以多项式、指数回归，相关性都很高。 通过对黄河1976年改道清水沟流路以后三角洲滨海区水深数据的定性、定量分析，可以将现黄河三角洲划分为侵蚀型、淤积型、基本稳定型三种。侵蚀型剖面上冲下淤，淤积型剖面由下凹型向典型的拦门沙形态发展，基本稳定型剖面形态变化很小。淤积型剖面淤积强度随时间推移而递减，并且水深越浅，淤积速度递减的越快；侵蚀型剖面侵蚀强度随时间推移而递减，随水深变深而变弱，但仍有较大的侵蚀强度和空间；侵蚀型剖面冲刷区与淤积区存在一个过渡带，称为最大侵蚀深度，最大侵蚀深度由无潮点沿三角洲北部岸线向西和沿三角洲东部岸线向南逐渐减小，与潮流速的变化相同，这是由于最大侵蚀深度可能只受潮流控制。 影响三角洲演变的因子很多，比如河流入海水沙通量、海洋动力、海平面升降、底质、地形地貌、植被、人类活动等等，就黄河三角洲而言，河流入海水沙通量是直接影响三角洲冲淤速率的最根本因素。本文在探讨三角洲演变与水沙关系时，在对各淤积型剖面等深线冲淤变化相对输沙量的关系进行研究基础上，再更多还原

【Abstract】 Water and sediment fluxes entering the sea is one of the international frontal problems in the earth science and is the important theme of two core projects of the International Global Biosphere Program (IGBP): the Joint Global Ocean Flux Study ( JGOFS ) and the Land-Ocean Interactions in the Coastal Zone (LOICZ), so studies on them have great implication for the study of global change. As far as Yellow River is concerned, it is the famous sandy river in the world, and used to transport 1.2 billion tons of suspended sediment annually to the sea, thus, contributing above 5% of the world’s annual sediment discharge. So the sediment from Yellow River plays an important role in the circle of the global sediment.Huge amount of the Yellow River sediment into the shallow Bohai Sea had constructed the modern Yellow River Delta most quickly in the world since 1855. However, the sediment flux decreased apparently in the last 50 years, the characteristic of delta evolution has been changing from deposition to erosion since 1996, especially the coast of Feiyantan and Gudong has eroded severely since the latest shift of the lower river course to Qingshuigou Channel in 1976. According to the measured data of water and sediment fluxes at Lijin hydrological station during the period 1950-2004 and the bathymetric records of 36 coastal profiles located around the current delta during the period 1976-2002, the multi-methods of hydrology, mechanics of sediment transport, statistics and GIS and the ideology of dynamic sedimentation and morphodynamics are applied to study the variations of the water and sediment discharge from river to the sea and their relation to the evolution of the Yellow River Delta in order to offer the scientific theory and decision-making evidence for the use of the water and sediment and the protection of the erosive coast. According to the study of decadal, yearly and seasonal variations in water and sediment fluxes to the sea and their relationship. The result shows that: 1) the water and sediment fluxes decreased apparently, especially the sediment flux in the last 20 years ; 2) the amount of water and sediment in flood season plays a very important role in the whole year, but this trend will weaken in the future; 3) there is a relatively good correlation between water and sediment fluxes, which is proved by different regressive equations.According to the qualitative and quantitative study of the bathymetric records of 36 coastal profiles since 1976, coastal profiles of the Yellow River delta are classified as更多还原