Mahmoud. A. Hassaan ( * )

Vol (5), No. (1), 1433 / 2012

p.p. 1 – 24 

Abstract:

Rosetta Nile branch promontory; the western headland of the Nile Delta retreated dramatically during the last century. Such a retreatment was accelerated since 1960s after the construction of the High Dam, which reduced the sediment load discharged at the Nile promontory. Moreover, these dramatic changes of the shoreline had a number of significant adverse impacts, which need to be assessed and analyzed. Such an assessment and analysis may assist decision and policy makers in mitigating the adverse impacts of shoreline changes.

The main objective of this paper is to assess and analyze various impacts of shoreline changes in the vicinity of Rosetta Nile branch promontory during the period from 1972 to 2005 through remote sensing and GIS techniques.

For that purpose, the paper applied two different methodologies in order to delineate shoreline from MSS, TM and ETM+ images for the study area in 1972, 1984, 1990 and 2005. For MSS image of 1972, the band ratio of [(Band3 + Band4) / Band1] was applied. Meanwhile, for TM images of 1984 and 1990 as well as ETM+ image of 2005 a combination of histogram threshold of band 5 and two band ratios (band 2/band 5 and  band 2/Band 4) was employed. Moreover, a geodatabase for the study area was developed to map and quantify shoreline changes. Also, the developed geodatabase was employed to analyze these changes spatially and assess their impacts

The study found that the maximum retreatment of the shoreline in Rosetta Nile branch promontory was about 3010 meter between 1972 and 2005 with an average retreatment rate of 91.21 m/year. Such dramatic changes of shoreline during the period 1972 – 2005 had a significant impact on the territory, infrastructure and land use pattern of the study area. For example, the study area has lost about 11.6 km2 of its territory during the period between 1972– 2005. Also, about 7.6 km of roads were lost. Moreover, retreating shoreline contributed to the development of wetlands, which in turn, affected land use pattern in the study area.

Keywords: Rosetta, band ratio, histogram threshold, shoreline changes.

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( * )  Associate Professor, Geography Department, Faculty of Arts, University of Damanhour mhassaan@hotmail.com