Autor: |
Jayaprakash, M., Sivakumar, K., Muthusamy, S., Krishnamurthy, R., Edward Patterson, J. |
Předmět: |
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Zdroj: |
Natural Hazards; Dec2016, Vol. 84 Issue 3, p1529-1538, 10p |
Abstrakt: |
Vaan Island, which is one of 21 islands in Gulf of Mannar Marine National Park, is chosen as study area which is formed above the coral reef by sedimentation and deposition of tidal and current activities. By using Landsat images, the area (Vann Island) was calculated from the year 1973-2015 with analyzing tools of Qgis and Saga Gis. Multispectral Landsat images were processed to extract and delineate the interface line of island surface and seawater. The area of each year polygon vector is calculated using the Qgis field calculator tool. During the 1973, the area of Vaan Island is about 265,479 m and at present the area is calculated as 40,733 m. About 84 % of the island area is reduced and inundated by the seawater due to sea level rise and anthropogenic activities such as coral sand mining, local tourism and fishing activities. At this rate of submergence, it can be predicted that by 2022 Vaan Island will completely submerge into the sea. From this study, it is concluded that geospatial techniques are one of the successful and reliable techniques to map this type of low-lying island to conserve and manage the resources that affected by the geogenic and anthropogenic processes. [ABSTRACT FROM AUTHOR] |
Databáze: |
Complementary Index |
Externí odkaz: |
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