Using Multi-temporal Remotely Sensed Data to Study
The Coastline Evolution in Dayanan Area
3. The coastline change in Dayawan Area
The comparison of the four-temporal remote sensing image shows that the coastline of the area changed dramatically, especially in Aotou Port, Depeng Port, Fanhe Port and Qianliao Port. With the rapid development of the regional economics, a variety of developing and construction activities, and the active man-made land-reclaiming projects make the coastline extend into the sea with the maximum of more than one kilometer. Apart from artificial factors, only considering the effect of natural factors, the coastline changes can be classified into four types such as,
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Eroded coast, where the coastline shrinks backward because of the strong erosion. The maximum of erosion is up to 200 meters according to the four-temporal images of Dapongwan and Xichong area.
- Silting coast,
- Shrinking and extension coast, and
- Stable coast, mostly belonging to bedrock coast, such as Dashuiwan, Dongchong and Jueliao port etc.
4. Conclusion and suggestion
The overlaying analysis of multi-temporal remote sensing data, not only shows the coastline change very, also
detects the power factors that cause the change, which is very useful for engineering constructiuon.
The coastal change map of this area shows that in the eroded coastal segments if there is not solid protection measures, the coast will be eroded repeatedly by the seawater. For instance, by comparing the coastal changes in 1973, 1986 and 1995 in Baishouwan area, the conclusion can be come up with that due to the strong erosion, the man-made coastline was destroyed and withdrew backward.
Although the natural condition in Dayawan area is relatively fine and there is abundant resource around the port with clear water and slow seawater flow, a variety of further studies are still necessary for engineering project. The detailed investigation and research will facilitate the engineering construction and the coastal protection.
