No abstract

Rosetta Promontory, Egypt has been suffering from a continuous erosion problem. The dramatic retreatment was observed during the last century. It is basically due to the construction of Aswan High Dam in 1964, which reduced the flow and sediment discharges. In this paper, four Landsat images (two Thematic Mapper and two Enhanced Thematic Mapper) covering the period from 1984 to 2014 were used. These Landsat images were radio-metrically and geometrically corrected, and then, multi-temporal post-classification analysis was performed to detect land cover changes, extracting shoreline positions to estimate shoreline change rates of the Nile delta coast around Rosetta Promontory. This method provides a viable means for examining long-term shoreline changes. Four categories, including seawater, developed (agriculture and urban), sabkhas (salt-flat), and undeveloped areas, were selected to evaluate their temporal changes by comparing the four selected images. Supervised classification technique was used with support vector machine algorithm to detect temporal changes. The overall accuracy assessment of this method ranged from 97% to 100%. In addition, the shoreline was extracted by applying two different techniques. The first method is based on a histogram threshold of Band 5, and the other uses the combination of histogram threshold of Band 5 and two band ratios (Band 2/Band 4 and Band 2/Band 5). For land cover change detection from 1984 to 2014, it was found that the OPEN ACCESSLand 2015, 4 217 developed area that increased by 9% although the land in the study area has been contracted by 1.6% due to coastal erosion. The shoreline retreat rate has decreased more than 70% from 1984 to 2014. Nevertheless, it still suffers from significant erosion with a maximum rate of 37 m/year. In comparison to ground survey and different remote sensing techniques, the established trend of shoreline change extracted using histogram threshold was found to be closely consistent with these studies rather than combining band ratio with histogram threshold.

No abstract

The rapid erosion in most coastlines is considered a major problem not only in Egypt, but also around the world. The main causes are due to anthropogenic activities and/or coastal hydrodynamics. The coastal zone suffers from sedimentation, accretion, and pollution problems as well as the side effect of climate change. The climate change will increase sea level rise, salt water intrusions, and storm surge. Major efforts has been exerted to manage coastal erosion problems and to restore coastal capacity in order to protect housing, infrastructure and the cultivated land. These problems were encountered with various types of hard structures, but most of these methods response were limited due to lack in evaluation of the entire ecological situation. This encouraged the coastal engineers to think about new types of environmental friendly structures work better with ecological situation. In this study, the protection measures worldwide is reviewed and divided mainly into four groups, hard, soft, combined, innovative measures. The usage and side effect of each type is mentioned briefly. It is clear that there is a predominant approach towards the soft engineering, the eco-engineering techniques, or combination between them in order to enhance the ecological situation. Recently, there are several efforts to apply these new technologies to protect the coastal zone as well as the environment by taking into consideration the effect of climate change. These new approaches in coastal protection are multi used, environmentally friendly, easy to modify and maintain, and efficient from an economic perspective. Previous efforts in solving coastal problems in Egypt are analyzed and discussed taking into consideration the experience of similar cases worldwide. It is clear that the environmental friendly coastal structure is more suitable to solve most of our coastal problems with saving our ecosystem and reduce the protection cost.

No abstract

No abstract

No abstract

Oceanography and Marine Research J o u rn al of Oc e a n o g ra p y h an d M a ri ne Res e a r c h