GIS-Based Analysis and Modeling of Coastline Erosion and Accretion along the Coast of Sindh Pakistan

On the basis of morphological characteristics and erosion - accumulation of sediment, it is possible to divide the stretch of the Gianh River from Co Cang to Cua Gianh (about 54km in length) into 3 sections as follows: Meandering channel (from Co Cang to Tien Xuan Isles): the length of the channel is 27.69km and the width of the channel is 80-250m. The channel is in the form of a meandering, narrow riverbed, flow plays a dominant role, deposition activities develop strongly at the convex side, while erosion occurs strongly in the concave side (cut side); Braided channel (from Tien Xuan Isles to Quang Phu): the length of the channel is 17.06km and the width of the channel is 800-2,200m. The channel is straight, the river bed is large and the depth of the river bed is 2-11m. Sedimentation occurs mainly at the bottom of the channel and creates bar in the middle of the channel; Straight channel (from Quang Phu to Cua Gianh): the length of the channel is 9.23km and the width of the channel is 800-1,000m. The channel is straight and the depth of the river bed is 8-12.5m. In addition to the role of river flow, it is strongly influenced by marine dynamics. The erosion and accretion activities occur mainly in estuaries. The results above show trend of river development: i) Meandering channel is the most vulnerable to changes for morphology of channel by erosion and accretion of sediment and can create 1-2 horseshoe pools by the river change line; ii) Braided channel mainly changes in the bottom of channel by the formation of channel bar; iii) Straight channel mainly changes in the estuary (the mouth of the river can be moved, enlarged or narrowed).

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An Analysis of Shoreline Changes Using Combined Multitemporal Remote Sensing and Digital Evaluation Model

Civil Engineering Journal ◽

10.28991/cej-2020-03091448 ◽

2020 ◽

Vol 6 (1) ◽

pp. 1-10 ◽

Cited By ~ 10

Author(s):

Dao Dinh Cham ◽

Nguyen Thai Son ◽

Nguyen Quang Minh ◽

Nguyen Tien Thanh ◽

Tran Tuan Dung

Keyword(s):

Remote Sensing ◽

Multiple Scales ◽

Evaluation Model ◽

Beach Erosion ◽

Shoreline Evolution ◽

The North ◽

Digital Evaluation ◽

Significant Difference ◽

Erosion And Accretion ◽

Multitemporal Remote Sensing

Cua Dai estuary belonged to Quang Nam province is considered to be one of the localities of Vietnam having a complex erosion and accretion process. In this area, sandbars are recently observed with lots of arguments about the causes and regimes of formation. This could very likely result of not reliable source of information on shoreline evolution and a lack of historical monitoring data. Accurately identification of shoreline positions over a given period of time is a key to quantitatively and accurately assessing the beach erosion and accretion. The study is therefore to propose an innovative method of accurately shoreline positions for an analysis of coastal erosion and accretion in the Cua Dai estuary. The proposed technology of multitemporal remote sensing and digital evaluation model with tidal correction are used to analyse the changes in shoreline and estimate the rate of erosion and accretion. An empirical formula is, especially, exposed to fully interpret the shoreline evolution for multiple scales based on a limitation of satellite images during 1965 to 2018. The results show that there is a significant difference of shoreline shift between corrections and non-corrections of tidal. Erosion process tends to be recorded in the Cua Dai cape located in the Cua Dai ward, especially in the An Luong cape located in the Duy Hai commune with the length of 1050 m. Furthermore, it is observed that there is much stronger erosion in the north side compared with south side of Cua Dai estuary.

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Coastal erosion and accretion in Kuwait – Problems and management strategies

Ocean & Coastal Management ◽

10.1016/j.ocecoaman.2017.05.014 ◽

2018 ◽

Vol 156 ◽

pp. 76-91 ◽

Cited By ~ 4

Author(s):

S. Neelamani

Keyword(s):

Coastal Erosion ◽

Management Strategies ◽

Erosion And Accretion

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Cross-Shore Suspended Sediment Transport in Relation to Topographic Changes in the Intertidal Zone of a Macro-Tidal Beach (Mariakerke, Belgium)

Journal of Marine Science and Engineering ◽

10.3390/jmse7060172 ◽

2019 ◽

Vol 7 (6) ◽

pp. 172 ◽

Cited By ~ 4

Author(s):

Evelien Brand ◽

Lars De Sloover ◽

Alain De Wulf ◽

Anne-Lise Montreuil ◽

Sander Vos ◽

...

Keyword(s):

Sediment Transport ◽

Suspended Sediment ◽

Intertidal Zone ◽

Field Experiments ◽

High Tide ◽

Laser Scanner ◽

Quantitative Agreement ◽

Suspended Sediment Transport ◽

Transport Direction ◽

Erosion And Accretion

Sediment transport is a key element in intertidal beach morphodynamics, but measurements of sediment transport are often unreliable. The aim of this study is to quantify and investigate cross-shore sediment transport and the resulting topographic changes for a tide-dominated, sandy beach. Two fortnight-long field experiments were carried out during which hydrodynamics and sediment dynamics were measured with optical and acoustic sensors, while the beach topography was surveyed with a permanent terrestrial laser scanner. Suspended sediment was generally well-mixed and currents were largest at approximately 1.5 m above the bed, which resulted in a peak in sediment transport at 1/3 of the high tide level. The mean transport direction was onshore during calm conditions (wave height <0.6 m) thanks to tidal currents and offshore during energetic conditions due to undertow. Oscillatory transport was always onshore because of wave asymmetry but it was subordinate to mean transport. The intertidal zone showed an alternation of erosion and accretion with formation of morphological features during energetic (no storm) conditionsand smoothening of the morphology during calm conditions. A good qualitative and quantitative agreement was found between the daily cross-shore suspended load and beach volume changes, especially during calm conditions.

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