Based on the superior natural environment of the coastal zone, the construction of the coastal zone has developed rapidly in recent years. In order to better adapt to the coastal zone and protect the coastal zone resources, we need to fully understand the sedimentary dynamic environment of the coastal zone, so this study was carried out. In this paper, the data of geographical environment and climatic factors in the study area are collected. Field observation was carried out in the study area, with satellite image analysis and software simulation, detailed studies were made on the evolution process of the shoreline, the stability of the shoreline and the sediment level in the last 20 years. On this basis, the conceptual model of sediment transport is presented, and the coastal dune can be used as a transport engine to drive sediment migration between coastal cells and maintain the stable development of the coastal area. Under the same dynamic conditions, once the engine is turned off, such as forest replacing natural coastal dunes, the sediment transport path is blocked, which will cause accretion of the upstream flank and erosion of the downstream flank. Human beings tend to change the natural environment for their own interests, and the feedback mechanism of the natural environment is often characterized by hysteresis effect, which is not worth the loss in the long run. We should respect nature and reduce unnecessary environmental damage.
 

Sediment budget imbalance; Land cover change; Coastal area; Coastal erosion and accretion