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Bohai Strait of Long Island county located in the Yellow Sea and Bohai Interchange North title Liaodong south Penglai Bohai throat. Long Island county by the many islands of the South Changshan Island, North Changshan Island, large Montenegrin Island, small Montenegrin Island and Temple Island. Since 1960, the South, North Changshan Island, connected by a tombolo west side of the hydro-dynamic conditions changed greatly, tends to siltation, water quality degradation, the deterioration of the ecological environment. , Remediation and restoration of the marine ecological environment, promoting the economic development of the island, 2002, the Shandong provincial government to determine the strategic decisions of the building north to south and Hill Bridge, makes the tomboloof the dismantle it possible to improve the traffic situation on the island. Based on years of the topography, hydrology, meteorology, sediment measured and historical information, the the use ECOMSED and the SWAN model to simulate the tidal current, wave field and bottom topography changes of erosion of the waters of the South, North Changshan Island The results show that: North and South Changshan Island waters tidal wave of progressive wave, high and low tide time maximum flow rate, rose ebb moment occurred bypass. During the ebb tide of overall outflow from the Bohai Sea from west to east, the average velocity of the surface of the range of between 30cm / s ~ 40cm / s. By Daheishan Island barrier trend is divided into north and south two, north branch by Changshan channel to bypass North Changshan Island to the southeast flow; south branch by Dengzhou waterway to bypass South Changshan Island eastward flow, and the North Branch intersection. Climax trend overall from east to west into the Bohai Sea, the surface average velocity range between 20cm / s ~ 40cm / s. Blocked by the South, North Changshan Island westward flow is divided into northern and southern branches, the North Branch to bypass the northern end of the North Changshan Island, the southern branch of bypassing South Changshan Island then south to southwest direction of flow. South, North Changshan Island East, West sides 50 years once the return period H13% wave height of 4.0m ~ 6.5m and 1.0m to 3.0m. The entire area to erosion the strong erosion areas are mainly located in big Montenegro Island north and south sides, the east side of the small Montenegrin Island north side and North Changshan Island, the erosion rate of up to 4.5cm / a; siltation area mainly located in North Mountain Island, South Changshan Island and Temple Island waters, siltation rate ranged between 0.5cm / a ~ 1.4cm / a. Maximum deposition area is located in the west side of the tombolo siltation rate to 1.4cm / a. Tomboloof removal of the tidal current, wave and topography with erosion and deposition are mainly located on both sides of the tombolo nearby waters. The maximum velocity variation of the original dam site to 45cm / s, about 2.0km east of the tombolo velocity change of less than 1cm / s west side about 4.7km velocity change of less than 1cm / s. Compared to the wind, with the North East wind role in the next wave of high change before and after, tomboloof dismantle 50 years return period wave height H13% change in the region greater than 0.1m about 5.94km2, mainly located in the west side of the tombolo. North Changshan Island, South Changshan Island and Temple Island waters from siltation to erosion, the maximum erosion rate up to 8.1cm / erosion rate will gradually reduce, and ultimately achieve erosion and deposition equilibrium.
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