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Mapping shoreline change using machine learning: a case study from the eastern Indian coast

Kumar Lalit, Afzal Mohammad Saud, Afzal Mohammad Mashhood

Acta Geophysica

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2020

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Vol. 68, no. 4

1127--1143

EN

The continuous shift of shoreline boundaries due to natural or anthropogenic events has created the necessity to monitor the shoreline boundaries regularly. This study investigates the perspective of implementing artifcial intelligence techniques to model and predict the realignment in shoreline along the eastern Indian coast of Orissa (now called Odisha). The modeling consists of analyzing the satellite images and corresponding reanalysis data of the coastline. The satellite images (Landsat imagery) of the Orissa coastline were analyzed using edge detection flters, mainly Sobel and Canny. Sobel and canny flters use edge detection techniques to extract essential information from satellite images. Edge detection reduces the volume of data and flters out worthless information while securing signifcant structural features of satellite images. The image diferencing technique is used to determine the shoreline shift from GIS images (Landsat imagery). The shoreline shift dataset obtained from the GIS image is used together with the metrological dataset extracted from Modern-Era Retrospective analysis for Research and Applications, Version 2, and tide and wave parameter obtained from the European Centre for Medium-Range Weather Forecast for the period 1985–2015, as input parameter in machine learning (ML) algorithms to predict the shoreline shift. Artifcial neural network (ANN), k-nearest neighbors (KNN), and support vector machine (SVM) algorithm are used as a ML model in the present study. The ML model contains weights that are multiplied with relevant inputs/features to obtain a better prediction. The analysis shows wind speed and wave height are the most prominent features in shoreline shift prediction. The model’s performance was compared, and the observed result suggests that the ANN model outperforms the KNN and SVM model with an accuracy of 86.2%.

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Assessment of Shoreline and Associated Landuse/Land cover Changes along Part of Lagos Coastline, Nigeria

Akinluyi F. O., Adebola A. O., Adeseko A. A.

Contemporary Trends in Geoscience

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2018

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Vol. 7, iss. 1

59--71

EN

The city of Lagos, Nigeria has undergone rapid increase in population due to economic and commercial activities. As a result of this, there has been a persistent change in Land use/Land cover (LULC) of the city and shoreline through the years. This observation necessitated the use of multi-temporal satellite data to characterize shoreline changes between 1984 and 2016. Therefore, the study attempts to determine the shoreline change during the study period and the coastal land use and land cover (LULC) of the study area. Satellite data was acquired and subjected to some image processing techniques such as image enhancement, supervised classification, and shoreline extraction. The digital shoreline analysis system (DSAS) in ArcGIS environment was utilized to cast transects and calculate statistical parameters for the shoreline and spatial data used was Landsat TM, ETM and OLI for the years 1984, 1990, 2000, 2004 and 2016 respectively. The results indicate that LULC changes in built-up areas increases rapidly during the years (1984-2015) from 12.2 -36.2%, water bodies increased from (1984-1990-2000) from 52%, 54%, 52% and reduces to 47.4% in the year 2015 while vegetation cover reduces drastically through the year range from 36%, 33%, 29%, 24% and 16%. A total of 1034 transects were generated with 100m spacing and the average rate of change was calculated for the 32 year period (1984-2016). The linear regression rate (LRR) shoreline result shows a mean of -0.59m/year where 73.1% of transect fall under erosion and 61.8% accretion respectively. The end point rate (EPR) and net shoreline movement (NSM) analysis revealed mean shoreline change of -0.57m/year and -18.1m/period respectively from 1984-2016. The EPR and NSM results both revealed that 231 transect or 22.3% experienced erosion, and 805 transect or 77.9% with accretion. It was observed that significant accretion rate recorded along most sections of the shorelines is attributed to beach nourishment activities.

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Sediment Transport Issues Related to a Planned Cross-cut through the Vistula Spit, Poland

Kaczmarek L. M., Ostrowski R., Szmytkiewicz M.

Archives of Hydro-Engineering and Environmental Mechanics

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2010

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Vol. 57, nr 2

119-137

EN

In order to make a navigable connection between the Vistula Lagoon and the Baltic Sea independent of an attitude of the Russian authorities, a cross-cut in the Polish part of the Vistula Spit is planned. The cross-cut will constitute an alternative waterway with respect to the existing one, leading through the Pilawa Strait which belongs to the Russian territorial waters. The new outlet will require breakwaters and an approach channel on the open sea side, as well as a waterway across the Vistula Lagoon to the harbour of Elbląg. The planned cross-cut is located about 3 km from the root of the Vistula Spit, at Skowronki village. The paper comprises an analysis of regional wave parameters in a mean statistical year on the basis of the Baltic wave climate reconstructed for the period of 44 years, together with a calculation of the longshore sediment transport rates. An influence of the planned coastal structures on the shoreline evolution, as well as the approach channel silting-up rates, in the first 10 years after the construction of the cross-cut, are estimated. An optimised layout of the planned approach channel and lengths of the planned breakwaters are recommended to facilitate the maintenance of the coast and the new waterway.

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Palaeoecology of basins of organic sediment accumulation in the Reserve Dury

Kowalewski G., Milecka K.

Studia Quaternaria

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2003

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Vol. 20

73-81

EN

The Reserve Dury, Tuchola Pinewoods, Poland, includes five depressions with no outflow filled up with biogenic sediments. They undergo terrestrialization processes to a high degree. In four of the basins there are still some open water areas surrounded by floating mire with raised and transitional bog plants. For the needs of protection service officers some palynological and geological research were carried out. All the geological cores were described in detail following the Troels-Smith system. The deepest core Dury I was selected for pollen analysis. Ten Local Pollen Assemblage Zones (L PAZ) show the history of regional and local plant communities. On the basis of two air photographs, modern dynamics of floating mire in four basins were evaluated. The results allow us to correlate the geological layers, to describe the Late Glacial and Holocene succession of plant cover at Dury I site, and to show the stages of filling-in of basins with lacustrine sediments and peat.