Allocations of water discharges between dry and flood seasons along the Yangtze River have significantly homogenized during the past decades, mainly due to precipitation change, regulation of key hydraulic works on the mainstream like the Three Gorges Reservoir (TGR), and the construction of numerous dams scattered in sub-basins. To reveal the specific roles of these three major factors in changing the seasonal discharges of the whole Yangtze River, this paper analyzes daily discharges during 1961–2014 at 16 hydrological stations from the far upper reach (the Jinshajiang Reach) to the estuary. We found that precipitation has only homogenized in areas 427 km downstream of the TGR, contributing 9.5–23.6% to the homogenized discharges. Even though the TGR is the largest hydraulic works in the world, it only contributes 17.5–27.2% to the downstream homogenization of seasonal discharge. By comparison, dams in sub-regions are a major contributor (61.1–100%) in the homogenized reach either upper or lower to the TGR. Of all the sub-basins, dams in Hanjiang River basin has the most significant effect (16.9%) on changing the allocations of seasonal discharges to the sea, followed by Wujiang (11.5%), Jialingjiang (10.1%), Yalongjiang (9.4%), Qingjiang (8.4%), and Daduhe-Minjiang (4.7%) river basins. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY 4.0), which permits copying, adaptation and redistribution, provided the original work is properly cited (http://creativecommons.org/licenses/by/4.0/). doi: 10.2166/nh.2020.143 s://iwaponline.com/hr/article-pdf/doi/10.2166/nh.2020.143/647382/nh2020143.pdf Yuanfang Chai Yao Yue (corresponding author) Sixuan Li Jinqiu Ren Haibin Xiong Xin Cui Yitian Li State Key Laboratory of Water Resources and Hydropower Engineering Science, School of Water Resources and Hydropower Engineering, Wuhan University, Wuhan 430072, China E-mail: 781186238@qq.com Boyuan Zhu Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Human Province, School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha 410114, China Yunping Yang Key Laboratory of Engineering Sediment, Tianjin Research Institute for Water Transport Engineering, Ministry of Transport, Tianjin 300456, China Xia Yan River Department, Yangtze River Scientific Research Institute, Wuhan 430010, China

中文翻译：

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长江季节性流量均一化的原因

在过去的几十年中，长江干汛和汛期水流量分配明显趋同，主要是由于降水变化、三峡水库等干流重点水利工程的调整以及众多水坝的建设分散在子盆地中。为了揭示这三个主要因素在改变整个长江季节性流量中的具体作用，本文分析了1961-2014年从远上游（金沙江段）到河口的16个水文站的日流量。我们发现降水仅在 TGR 下游 427 公里的地区均质化，对均质化排放量的贡献为 9.5-23.6%。尽管 TGR 是世界上最大的液压工程，但它仅贡献 17.5-27。2%向下游均质化季节性排放。相比之下，子区域的大坝是 TGR 上部或下部均质河段的主要贡献者（61.1-100%）。在所有子流域中，汉江流域的大坝对改变季节性入海流量分配的影响最显着（16.9%），其次是吴江（11.5%）、嘉陵江（10.1%）、雅龙江（9.4%） )、清江 (8.4%) 和大渡河-闽江 (4.7%) 流域。这是一篇根据知识共享署名许可 (CC BY 4.0) 条款分发的开放获取文章，该许可允许复制、改编和重新分发，前提是正确引用原始作品 (http://creativecommons.org/licenses/by/ 4.0/)。doi：10.2166/nh.2020.143 s://iwaponline.com/hr/article-pdf/doi/10.2166/nh.2020.143/647382/nh2020143。