The analysis of the beach changes in two islands as major sea turtle nesting sites in the northern Arabian Gulf using multiple image processing methods

Abstract:

Changes in the landscape over the decades have a major impact on the areas which has rich biodiversity and high ecological values. Such changes occur in an island's results with the decay of beach sand which brings potential threats to the natural habitat of sea turtles. Given such impacts, it is important to understand the changes in the landscape to make some conservation efforts to minimize the extinction of endangered species worldwide. In this study, changes in Jana and Karan islands area from 1970 to 2017 were compared using image processing techniques such as edge detection and thresholding. Images of Jana and Karan islands are collected using USGS-LandsatLook viewer which includes satellite images from Landsat 8 OLI and Landsat 1-5MSS sensors. Edge detection methods such as Canny, Sobel, Prewitt, and Laplacian of Gaussian is applied to detect the edges of both island and area is calculated after preprocessing the images. According to the Canny method, Jana island has reduced about 16% of land area and 20% for the Prewitt method from 1970 to 2017. Sobel method indicates that 19% of Jana island reduced over this period whereas Laplacian implies an extremely high value of 28% reduction of Jana land due to some edges detected outside the land even after applying the thresholding technique. Karan island has reduced 5% of the area as reported by the Laplacian method and 8% reduction of land area for the Sobel method from 1972 to 2017. Canny and Prewitt method has shown the 6% and 7% reduction in Karan island, respectively. Canny method outperformed all other edge detection methods for both Jana and Karan Island. The Laplacian method demonstrates some exceptional results for the analysis conducted for both islands.