Changes in coastal line and their impact on coastal tourist services in Damietta governorate, Egypt by Using Remote Sensing and GIS Techniques [ ]

Damietta coastal plain northern of Nile Delta, is a very promising area for energy resources, tourism and industrial activities. It suffered from several changes over the past century, especially in its boundaries and topography. The objective of this work was to study the spatial and temporal changes that took place along the coastal line of Damietta governorate by using RS and GIS techniques. This is in addition to providing an accurate estimation of the areas where erosion and deposition processes take place. For that purpose multi-temporal Landsat data were collected in 1984, 2000, 2011 and 2014. Also, two spectral indices were used in this study, which are the Normalized Difference Water Index (NDWI) and the World View Water Index (WVWI)) to study the changes along the coastal water/land interface. The obtained results indicated that the eroded areas were about 14.08 km2 from 1984 to 2000, about 3.54 km2 from 2000 to 2011, and about 2.05 km2 from 2011 to 2014. The erosion rate during the studied period from 1984 to 2014 was about 0.41 km2/ year. The areas were deposition take place was about 4.92 km2 during the period from 1984 to 2000, about 4.94 km2 from 2000 to 2011 and about 6.35 km2 from 2011 to 2014. The deposition rate during the whole studied period was about 0.291 km2/ year. Accordingly, the deposition rate along the coastline was higher than the erosion rate, however it took place at different locations. Some of these areas were naturally occurred, however some others were human induced, especially after 2011. Accuracy assessment revealed that WVWI was more accurate than the NDWI in studying the changes along the coastal line. Different scenarios about the possibilities of costal submersion as a result of possible tsunamis or global warming were also studied. These scenarios indicated that a possible area of about 75.89 km2 of the coastal land could be submerged in case of a sea level raised by about 5 meters. The obtained results and the hypothetical views were also considered in setting the criteria for selecting the most suitable and secure areas for tourist.