Reclamation impact on coastal topography in Sheyang estuary

The large scale reclamation in coastal area is the important reason to cause scouring-silting change of muddy tidal flat. The paper adopts higher resolution images in different periods to quickly extract border dike line and average high-tide line, which is used to analyse that reclamation influences on the coastal topography. There are two results: firstly, the beach line of northern Sheyang estuary is mainly in erosion at the rate of 4~6 m/a from 1995 to 2003; and its south is in siltation at the average rate of 35 m/a except the highest rate of Wutiao harbor is 199.2 m/a from 1995 to 1999, then the average rate is 11 m/a except the highest rate of Miyang harbor is 79.4 m/a from 1999 to 2003. Secondly, the seawall in the north estuary is almost stable from 1995 to 1999 while it extends seaward about 0.94 km from 1999 to 2003; and its south extends seaward about 4.08 km from 1995 to 1999 and 2.56 km from 1999 to 2003.