Analysis of morphodynamic evolution in a meandering estuarine channel in the context of climate change

气候变化背景下蜿蜒河口航道形态动力学演化分析

• 批准号: 20K14840
• 负责人: Azhikodan Gubash
• 金额: $ 2.66万
• 依托单位: Tokyo Metropolitan University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Early-Career Scientists
• 财政年份: 2020
• 资助国家: 日本
• 起止时间: 2020-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-20K14840/
• 关键词: morphodynamics; Chikugo River estuary; long-term; tidal forcing; bed elevation; sediment supply; sediment transport; topographic change; erosion; peak flood; Morphology; Topographic survey; Salinity intrusion; Climate change; Sediment transp

On a long-term basis, the whole study period was divided into three based on the time of human activities and disasters occurrence; (1) the period of human activities (1953-1998), (2) the period of no human activities and no disasters (1998-2003), and (3) the period of disasters (2003-2022). During period-1, the riverbed was lowered due to extensive human activities such as dredging (flood control), land reclamation, sand mining, etc. During period-2, the bed elevation increased by 0.5-1 m, which was due to the tide-induced landward sediment transport and deposition process. During period-3, the bed elevation decreased as extreme flood disasters eroded the sediment deposited upstream of the estuary. Although the extreme floods and landslide disasters supplied massive sediments into the Chikugo River, it seemed that sediments supplied by disasters were trapped upstream of the river and were not enough to reach the estuary. The erosion of existing deposits and lack of sediment supply from the upstream caused the decrease in estuarine bed elevation during period-3.

在长期的基础上，根据人类活动和灾害发生的时间将整个研究期分为三个阶段：（1）人类活动期（1953-1998），（2）无人类活动和无灾害期（1998-2003），（3）灾害期（2003-2022）。在第一阶段，河床降低，由于广泛的人类活动，如疏浚（防洪），土地复垦，采砂，在第二阶段，床高程增加了0.5-1米，这是由于潮汐引起的向陆地的泥沙输移和沉积过程。在第3阶段，由于极端洪水灾害侵蚀了河口上游沉积的泥沙，河床高程下降。尽管特大洪水和滑坡灾害向筑后河提供了大量沉积物，但灾害提供的沉积物似乎被困在河流上游，不足以到达河口。现有沉积物的侵蚀和上游沉积物供应的缺乏导致河口河床高程在第3期下降。

项目成果

LONG-TERM (1953-2020) MORPHOLOGICAL CHANGES OF CHIKUGO RIVER, JAPAN

日本筑后河的长期（1953-2020）形态变化

• DOI: 10.1142/9789811275449_0043
• 发表时间: 2023
• 期刊: Proceedings of the 19th Annual Meeting of the Asia Oceania Geosciences Society
• 作者: Phyu P.E.;Yokoyama K.;Azhikodan G.
• 通讯作者: Azhikodan G.

PHYTOPLANKTON HABITATS RESPONSE TO THE VARIABILITY OF ESTUARINE HYDRODYNAMIC CONDITION IN THE MACROTIDAL CHIKUGO RIVER ESTUARY

筑后江口大潮汐浮游植物生境对河口水动力条件变化的响应

• DOI: 10.1142/9789811275449_0041
• 发表时间: 2023
• 期刊: Proceedings of the 19th Annual Meeting of the Asia Oceania Geosciences Society
• 作者: Nwe Lett Wai;Yokoyama Katsuhide;Azhikodan Gubash
• 通讯作者: Azhikodan Gubash

Phytoplankton habitats and size distribution during a neap-spring transition in the highly turbid macrotidal Chikugo River estuary

高浑浊大潮汐筑后河口小春过渡期间浮游植物栖息地和大小分布

• DOI: 10.1016/j.scitotenv.2022.157810
• 发表时间: 2022
• 期刊: Science of The Total Environment
• 影响因子: 9.8
• 作者: Nwe Lett Wai;Yokoyama Katsuhide;Azhikodan Gubash
• 通讯作者: Azhikodan Gubash

CHANGES IN SIZE DISTRIBUTION OF PHYTOPLANKTON IN RESPONSE TO TIDAL VARIABILITY IN THE CHIKUGO RIVER ESTUARY

筑后河口浮游植物大小分布对潮汐变化的响应

• DOI: 10.2208/jscejhe.78.2_i_1069
• 发表时间: 2022
• 期刊: Journal of Japan Society of Civil Engineers, Ser. B1 (Hydraulic Engineering)
• 作者: NWE Lett Wai;AZHIKODAN Gubash;YOKOYAMA Katsuhide
• 通讯作者: YOKOYAMA Katsuhide

Tokyo Metropolitan University - Researcher page

东京都立大学 - 研究员页面