EROSION AND RESTORATION OF THE GRAVEL BEACH AROUND LONG ISLAND, SHANDONG

Due to the changes in natural environment and intensification of human activities, coastal erosion has become a severer challenge to human society recently. Gravel beach nourishment, as a new performance to beach conservation, has rapidly developed in coast defense of the world. Due to its coarse particle size and high porosity, the gravel beach has the capability to filter water out when they are under wave actions. The higher penetration rate of water may make the beach more stable. In 2014 and 2016, the authors conducted two field surveys on the gravel beach at the Long Island, Shandong Province. It is found that the gravel beach there was under erosion, the maximum erosional depth of the beach face was up to 0.6 m, and the width of the beach was narrow. Therefore, it is recommended that the beach be nourished with gravels for beach conservation. According to the local conditions and the cases of some foreign gravel banks, it is known that the location for gravel dumping should be above the high tide line, and the filling thickness should not be less than 3 to 4 meters. The gravels with a diameter of 2-50 mm are the best choice and then widen the beach shoulder up to 30 meters. The beach will remain stable for a period of time as normally required. Governmental management should be strengthened to prevent vandalism. Once the gravel beach is restored, it can not only protect the coast, but also push forward the development of local tourism.