Article
Environmental Sciences
Jongwi Chang, Guan-hong Lee, Courtney K. Harris, Steven Miguel Figueroa, Nathalie W. Jung
Summary: This study aims to understand the impacts of human alterations on the Nakdong Estuary in Korea through simulations. The results showed that the estuarine dam had a larger influence on the estuary than land reclamation, and their combined effect was more significant. These findings can be applied to other estuaries that have experienced human alterations.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
Jing Liu, Yitong Lin, Zixiao He, Feng Liu, Liangwen Jia, Wen Wei
Summary: This study investigates the dynamics of flow and sediment under flood conditions in a river-dominated estuary using numerical modeling. The results show that the flow velocity exhibits a Gaussian distribution in the transverse direction and decreases linearly in the longitudinal direction. Two distinct zones, namely the zone of flow establishment (ZOFE) and the zone of established flow (ZOEF), are identified. Tidal dynamics are found to play a crucial role in altering the range of flow diffusion. Increased flood intensity has little effect on the flow structure and erosion/deposition pattern, but significantly increases the seaward current velocities and bed level changes, as well as the transverse diffusion range of the flow and sedimentation.
FRONTIERS IN MARINE SCIENCE
(2023)
Article
Environmental Sciences
Damien Pham Van Bang, Miguel Uh Zapata, Georges Gauthier, Philippe Gondret, Wei Zhang, Kim Dan Nguyen
Summary: This paper presents experimental and numerical studies on the erosion of a horizontal granular bed by a two-dimensional plane vertical impinging jet. The simulations help understand the microscopic processes that govern erosion in this complex flow. A unique relationship between the crater size and a local Shields parameter is successfully obtained using a modified jet-bed distance.
Article
Oceanography
E. F. Eidam, D. A. Sutherland, D. K. Ralston, T. Conroy, B. Dye
Summary: Estuaries worldwide have undergone modifications over centuries, impacting sediment dynamics. The Coos Bay Estuary in Oregon, a small estuary with complex geometry, has experienced significant changes since 1865, leading to alterations in tidal amplitudes, salinity intrusion, and estuarine flow. These changes have resulted in reduced current magnitudes, increased stratification, and the formation of an estuarine turbidity maximum supplying sediment to proximal embayments.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Meteorology & Atmospheric Sciences
Rui Zhang, Bo Hong, Lei Zhu, Wenping Gong, Heng Zhang
Summary: This study examined the morphological evolution and hydrodynamic responses of the Huangmaohai estuary in southern China. The results showed that human activities have significantly changed the estuary's topography and modified its circulation patterns.
Article
Engineering, Civil
Le Ngoc Anh, Dung Duc Tran, Nguyen Thong, Can Thu Van, Dang Hoa Vin, Nguyen Hai Au, Edward Park
Summary: Recent riverbed sand mining activities have significantly altered estuarine morphology and sedimentation patterns in Southeast Asian deltas. The Soai Rap Estuary in Southern Vietnam is one of the most intensively mined areas in the region. This study used hydrodynamic modeling to investigate the effects of intensive riverbed mining on the estuarine morphology and sediment dynamics. The results showed that dredging activities substantially changed the hydraulic regimes, morphological patterns, and sediment dynamics of the estuary.
JOURNAL OF HYDROLOGY
(2022)
Article
Oceanography
Dongxue Yu, Guangxuan Han, Xiaojie Wang, Baohua Zhang, Franziska Eller, Jinying Zhang, Mingliang Zhao
Summary: The study on the Yellow River Delta wetlands found that their evolution is influenced by runoff, sediment load, and human activities, resulting in a decrease in natural wetlands converted into human-made wetlands and non-wetlands.
OCEAN & COASTAL MANAGEMENT
(2021)
Article
Environmental Sciences
Kazumi Terada
Summary: This study investigated the impact of tidal changes on water quality and nutrient fluxes in a mangrove estuary in Japan. The results showed that there were differences in nutrient concentrations and fluxes between different years, and that the water and TN fluxes were influenced by rainfall.
MARINE ENVIRONMENTAL RESEARCH
(2022)
Article
Environmental Sciences
David K. Ralston
Summary: Gated storm surge barriers, which are open during non-storm periods but block tidal exchange during storms, can have significant impacts on sediment dynamics in estuaries. The presence of a storm surge barrier near the estuary mouth increases bottom stresses, causing erosion and coarsening of the bed. This leads to a reduction in suspended sediment concentration near the barrier, along with reduced tidal amplitude and increased trapping of sediment input from the watershed inside the estuary. However, the overall impact on sediment dynamics in the Hudson River estuary is expected to be modest.
ESTUARIES AND COASTS
(2023)
Article
Oceanography
Galen Egan, Grace Chang, Andrew J. Manning, Stephen Monismith, Oliver Fringer
Summary: This study conducted field work and collected data in a wave- and current-driven estuarine environment to examine cohesive sediment flocculation dynamics. The study found that the factors driving floc size variability differed between locally sourced sediment and suspended sediment advected from upstream. The analysis also revealed seasonal variability in these trends and presented evidence of a relationship between floc size and the inverse turbulent Schmidt number.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Geosciences, Multidisciplinary
Zhuo Zhang, Fei Guo, Zhiyao Song, Peng Chen, Fengfu Liu, Dong Zhang
Summary: A numerical study based on the FVCOM model was conducted to investigate the storm surge behavior induced by Typhoon Mangkhut in and around Lingdingyang Bay, Pearl River Estuary. The simulation results matched well with the measurements from tidal-gauge stations, and a series of artificial typhoons were designed to study the influence of typhoon uncertainties on the storm surge response. The study found that factors such as landfall time, central pressure deficit, and track direction can significantly impact the behavior of storm surge.
Article
Environmental Sciences
Zhiyuan Han, Heng Wang, Hualiang Xie, Huaiyuan Li, Wendan Li
Summary: The morphological changes in Lingding Bay, influenced by fluvial and oceanic dynamics as well as human activities, have been examined using bathymetric data and remote sensing images. The study reveals that high-intensity sand-dredging activities have led to considerable deepening and increased water volume in the bay since 2007. These recent changes pose challenges for estuary regulation, disaster control, environmental protection, and operational safety of nearby ports and channels.
Article
Engineering, Environmental
G. Shiravani, D. Oberrecht, L. Roscher, S. Kernchen, M. Halbach, M. Gerriets, B. M. Scholz-Bottcher, T. H. Badewien, A. Wurpts
Summary: Microplastic (MP) pollution poses a significant challenge to both human life and the natural system. The irresponsible handling of plastics in daily life has led to a rapid contamination of air, water, and soil with MP. This study focuses on the modeling of MP transport and interaction with fine sediment in estuarine turbidity zones (ETZ), proposing a new approach to improve the formulation of MP settling velocity in these conditions. The model results indicate higher concentrations of MP in ETZ, both in the water column and the bed sediment, which is supported by measurements. Additionally, the model suggests that smaller MP particles are more likely to escape the ETZ and move towards the open sea.
Article
Environmental Sciences
K. Radhakrishnan, V. Sivapriya, A. Rajkumar, N. Akramkhan, P. Prakasheswar, S. Krishnakumar, S. M. Hussain
Summary: The study found that microplastics in the sediments of the Kayamkulam estuary are primarily fiber and film shaped, with 1000 mu m microplastics being dominant, and polyester polypropylene and polyethylene being the main compositions. The distribution of microplastics is influenced by estuarine inundating water and the distance of the sampling site from the open sea.
MARINE POLLUTION BULLETIN
(2021)
Article
Environmental Sciences
Jinyang Wang, Yoeri M. M. Dijkstra, Huib E. de Swart
Summary: The aim of this study is to understand the processes that determine the dynamics of estuarine turbidity maximum (ETM) in channel networks. It is found that the ETM dynamics in a network is coupled, with changes in one channel affecting the ETM pattern in all channels. Additionally, the deepening or narrowing of a seaward channel can influence the ETMs in the entire network.
FRONTIERS IN MARINE SCIENCE
(2022)