Environmental Fluid Mechanics, Год журнала: 2019, Номер 19(6), С. 1575 - 1598
Опубликована: Апрель 4, 2019
Язык: Английский
Water Resources Research, Год журнала: 2024, Номер 60(5)
Опубликована: Май 1, 2024
Abstract The initiation threshold of sediment motion, a key component in quantifying transport, has potential link to intermittent turbulence bursts. Here, we elaborated situ experiments on coastal sea bottom covered with cohesive sediments, obtain intermittency parameters. variable “waiting time” between bursts was utilized capture the occurrence events natural waters. A relationship waiting time and shear stress reveals different features flux series before after reaching threshold, which can be used determine motion. Multi‐site results demonstrate limitations traditional empirical formulae for fine‐grained where cohesiveness becomes more pronounced as grain size decreases deviation reach 600%. formula modified using size, calculations were good agreement observed values, will greatly assist transport geomorphology model predictions.
Язык: Английский
Процитировано
1
Earth Surface Processes and Landforms, Год журнала: 2020, Номер 45(11), С. 2463 - 2477
Опубликована: Май 10, 2020
Abstract Coastal deltaic deposits are the primary locations for sediment storage on Earth, and quantifying their source contributions is a critical prerequisite delineating S2S patterns in marginal seas. In most cases, quantification contribution by fine‐grained sediments (i.e. particle size < 63 μm) considered to be representative constrain overall supply. However, this approach may inappropriate because large differences exist between two quantities. Here we propose an solve problem, which based maximum number of tracers from multiple fractions incorporating content all sediment. Using approach, absolute during Holocene reconstructed that provide first‐order model pattern central Jiangsu coast, China. The Huanghe River strongest driver sedimentation, with mean ~72 ± 6% (1417 × 10 8 t). Changjiang offshore areas were secondary importance, ~17 1% (330 t) ~11 5% (217 t), respectively). results show difference relative assumption represents invalid coastal setting. impact mainly episodic events, such as event 1128–1855 AD . also reveals important coast Holocene. Thus, provides both time series quantities supply formation evolution tidal flats coast. Our findings shed new light quantitative analysis sources applicable future studies © 2020 John Wiley & Sons, Ltd.
Язык: Английский
Процитировано
11
International Journal of Digital Earth, Год журнала: 2022, Номер 15(1), С. 1676 - 1691
Опубликована: Окт. 10, 2022
In this study, we sampled the original sediment columns from three points located in eastern, central, and western areas of Chaohu Lake, then investigated resuspension under hydraulic disturbances laboratory. The results showed that when disturbance is weak surface shear stress small (<0.02 N/m²), layer moves alone. When moderate within a threshold (3.7 only proportion sediments begins to move. However, further strengthened larger than value, move smoothly. By experimental results, found plankton about 1 mm (1.56% maximum content suspended matter (SSCmax)), which major contribution individual initiation. new 19–22 (20.9% SSCmax), considerably affects shallow lakes. consolidated 22 below bed surface, requires high hard be transferred water column. quantified observation are verified with theoretical results.
Язык: Английский
Процитировано
7
Frontiers in Earth Science, Год журнала: 2022, Номер 10
Опубликована: Авг. 19, 2022
The hydrodynamics and sediment characteristics of muddy estuaries coasts during typhoons are closely related to the geomorphic evolution, ecological environment, economic development coastal zones. Taking macro-tidal turbid Hangzhou Bay (HZB) as an example, effects wave-current interactions on dynamics Typhoon Mitag were studied using a fully-calibrated numerical model. model considered tide-wave reconstructed typhoon wind field. Net fluxes controlled by residual currents suspended concentration (SSC). combined waves led high SSC typhoon. Under calm weather conditions, impact (wave dissipation, form drag, wave radiation stress, mean current advection refraction) was small, except for bottom stresses. stress primary interaction that changed resuspension increased SSC, particularly in shallow waters or storms. term, which played essential role reducing HZB, mainly affected increasing velocity. dissipation term enhanced vertical mixing, involved exchange currents. In southern bay, mostly decreased stresses, currents, deep waters. refraction terms relatively small. These findings provide theoretical foundation study dynamic geomorphology estuaries.
Язык: Английский
Процитировано
6
Environmental Fluid Mechanics, Год журнала: 2019, Номер 19(6), С. 1575 - 1598
Опубликована: Апрель 4, 2019
Язык: Английский
Процитировано
9