| 摘要: |
| 黄河入海流路自1976年5月改道至清水沟流路以来，其地貌形态一直处于剧烈的变化当中，以往的研究虽然关注了典型断面主槽的形态特征及过流能力的变化，但对于清水沟流路范围界限内河道断面整体形态及其沿程变化等地貌特征还缺乏系统研究。本文以2019年10月黄河口现行清水沟流路范围渔洼以下河段加测横断面为研究对象，辨识现状地貌分布特点和横断面沿程形态特征，并分析其成因。结果表明：黄河口地貌形成受自然演变和人类活动的影响，既具有主槽、滩地、堤防等河流地貌要素，又具有滩涂、潮沟、拦门沙等海洋地貌要素。在有堤防河段，主槽形态窄深，过流能力较强；在无堤防河段，主槽形态宽浅，过流能力较差；从滩槽高差、唇滩高差、滩地横比降三个指标来看，无堤防河段的"自然悬河"程度大于有堤防河段的"二级悬河"程度。黄河口悬河程度小于黄河下游大部分河段，但黄河口尾闾河道的滩地横比降依然远大于河道纵比降，若发生漫滩洪水将极易引起顺堤行洪，会对黄河口堤防安全造成极大威胁。 |
| 关键词: 形态特征 地貌 清水沟流路 黄河口 |
| DOI：10.11759/hykx20201213001 |
| 分类号:TV856 |
| 基金项目:国家重点研发计划项目（2017YFC0405502）；黄河水利科学研究院基本科研业务费专项（HKY-JBYW-2019-03，HKY-JBYW-2020-11） |
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| Geomorphic characteristics of the Qingshuigou flow path in the Yellow River estuary |
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DU Xiao-kang1,2, WANG Kai-rong1, PEI Hong-yang3, DOU Shen-tang1, BI Nai-shuang2, ZHANG Xin1
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1.Yellow River Institute of Hydraulic Research, Yellow River Conservancy Commission, Zhengzhou 450003, China;2.College of Marine Geosciences, Ocean University of China, Qingdao 266100, China;3.School of Water Conservancy and Hydropower Engineering, Xi'an University of Technology, Xi'an 710048, China
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| Abstract: |
| The topography of the Yellow River flow path into the sea has undergone drastic change since it was diverted to the Qingshuigou flow path in May 1976. Although previous studies have studied the changes in the morphological characteristics and flow capacity of the main channel of the typical section, the overall shape of the channel section within the boundary of the Qingshuigou flow path and its change characteristics along the channel are still lacking in systematic research. Based on a measured cross section of the river below Yuwa in the current Qingshuigou flow path of the Yellow River estuary in October 2019, this study recognizes the geomorphic features of the typical cross section, calculates the cross-sectional morphological indicators, and systematically analyzes the morphological characteristics of the main channel and the degree of the perched river. Results show that the geomorphological structure of the Yellow River estuary, which is affected by natural evolution and human activities, exhibits not only the riverine characteristics of the lower Yellow River but also oceanic characteristics. In the reach with embankments, the main channel is narrow and deep in shape with a strong flow capacity, while in the reach without embankments, the main channel is wide and shallow in shape with a poor flow capacity. From three indexes of elevation difference between beach and main river channel, elevation difference between natural levee and beach, and the transverse beach slope, it can be seen that the degree of "natural perched river" in the reach without embankment is greater than the degree of "secondary perched river" in the reach with embankment. Although the degree of "perched river" at the mouth of the Yellow River is weaker than that at most of the lower reaches, the beach transverse slope is still much larger than the longitudinal slope of the river at the Yellow River estuary. If flooding occurs, it will easily flood along the embankment toe, posing a great threat to the security of the embankment in the Yellow River estuary. |
| Key words: morphological features geomorphology Qingshuigou flow path Yellow River estuary |
