| 摘要: |
| 根据历史文献资料，对黄河夺淮期间淮河入海河口的动力条件、地貌特征及其演变机制进行了研究。结果表明，历史时期因大量多泥沙黄河径流汇入，淮河河口径流量、输沙量增大，但不同时期输沙量又受黄河下游反复进行的沿程淤积的影响而有变化。淮河口是中等强度的潮汐河口，其往复潮流和沿岸流系统非常有利于入海泥沙扩散。淮河口呈上窄下宽的喇叭口形，口门内、外侧分别发育有大规模拦门沙及水下三角洲，河口段河道具有典型的弯曲河型，自18世纪以后口门宽度有增大的趋势。淮河口演变的机制是潮流界不断向下游迁移、河口不断向海延伸，而且潮流界下移距离远大于同期河口外延距离，河口段长度急剧缩短。为了适应径流、潮流消能的需要，河口段河型向曲流化发展、口门展宽。古淮河人海河口和现代黄河河口具有不同的动力地貌特性和演变机制，其间不能作简单类比。 |
| 关键词: 河口 淮河 潮流界 河型 黄河 |
| DOI： |
| 分类号: |
| 基金项目:教育部重大科技资助项目，0119;河口海岸国家重点实验室开放基金资助项目，99003号 |
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| DYNAMIC PROCESSES, GEOMORPHOLOGY OF THE HUAIHE RIVER ESTUARY AND ITS EVOLUTION MECHANISM ASSOCIATED WITH CAPTURE BY THE HUANGHE RIVER |
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WANG Qing, LI Dao-ji, MENG Qing-hai, CHEN Ji-yu
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State Key
Lab of Estuarine & Coastal Research, East China Normal University
Shanghai, 200062
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| Abstract: |
| The Huanghe River discharged into the southern Yellow Sea through the Huanghe River estuary from 1128 to 1855 A.D., which resulted in flooding and waterlogging in the middle and lower Huaihe River basin. On the other hand, the modern channel of the lower Huanghe River is often taken as an analogy with the old Huanghe River. Therefore, in order to provide a theoretical foundation for appropriate harnessing plans of both the Huanghe and Huaihe rivers, it is necessary to study the geomorphic evolution in the lower Huaihe River basin. However, except for the coastline evolution of the old Huanghe River delta since 1128 A. D., no attention has been paid to the estuarine morphodynanic evolution of the Huanghe river estuary during 1128 to 1855 A. D.. Based on historical literarures, this paper has discussed the dynamic processes, geomorphology of the Huaihe River estuary during this period of time. Compared with the contemporary Huanghe River, the Huaihe River estuary has a large runoff and silt discharge which, was effected by the downfilling which took place in the lower Huanghe River valley for several times. The Huaihe estuary is a meso-tidal estuary with an average tide range of over 3.2m. the tidal current and coastal current help silt diffuse into the Yellow Sea rapidy. The Huaihe River estuary is funnel-shaped with two crossing spits, a large bay mouth sand bar and submerged delta. The channel of the estuary has an obvious meander form. The width of the mouth has a trend of increasing since 1700 A. D.. During 1128–1855 A. D. the tidal current limit migrated along the river continuously, and the estuary stretches toward the sea at the same time. Because the tidal current limit has a migrating distance much larges than the stretching distance of the mouth position, the length of the estuary channel below the tidal current limit becomes piogressively shorter. In response to the energy dissipation and the reduction the longitudinal gradient, the estuarine channel developed a distinctly meandering pattern. Thus, the Huanghe and the old Huaihe Rivers have estuaries with different types, and there is no estuarine dynamorphic basis for the analogy between them. |
| Key words: Estuary, the Huaihe River, Tide, Channel patten, the Huanghe River |
