Evaluation of Shoreline Dynamics Analyzing Spatial Temporal Data

Abstract

Shoreline change is considered as one of the most dynamic processes in the coastal regions. Shoreline spatial location mentions to several different features such as vegetation line, high water line, low water line, or the wet/dry line. They can be generated from a variety of spatial temporal data sources, like satellite imagery, digital orthophotos, historical coastal-survey maps and field observed spatial data using Global Positioning System. The undertaken work focuses on analysing shoreline dynamics, using spatial temporal data, by taking advantage of Geographic Information System (GIS) and Remote Sensing (RS). Multi year’s shoreline mapping is a valuable method for shoreline monitoring and assessment. The study area extends from the Port of Shengjin (North), to the delta of Drini river (South), a segment of Drini bay shoreline with a length of about 17 km. The available data used to generate shorelines spatial location include topographic maps at scale 1: 75 000, year 1918 (MGI); topographic maps at scale 1: 50 000, year 1937 ( GMIF); topographic maps at scale 1: 25 000, year 1985 ( AGMI) ; digital orthophotos of year 2007 and field observed GPS data, year 2014. The net rates of variations NSM (Net Shoreline Movement) of the shoreline position are calculated according to transects inclined perpendicularly to the baseline and spaced equally along the coast using DSAS (Digital Shoreline Analysis System). NSM represents the distance between the oldest and youngest shorelines. Analyses of the data shows that 35% of coastline of study area is in accretion process meanwhile 65% is in erosion process. Maximum rate of erosion is near to the mouth of Drini river with 10-12m/year in the last years, in average 7.5 m/year in the north side and 4 m/year in the south side of the river delta.