Impacts of Human Interventions on Water Exchange Ability in Jiaozhou Bay, China

Jiaozhou Bay (JZB), a semi-enclosed bay in China, has been significantly affected by continuously increasing anthropogenic activities, such as land reclamation and a cross-bay construction. These activities have directly resulted in changes in topography, and then consequently influenced water exchange ability in JZB. A hydrodynamic model has been established for JZB to evaluate the water exchange ability at different year: 1935, 1966, 1986, 2000, 2008, and 2013. The impacts of the changes in coastline and bathymetry are analysed. In order to study on detailed reasons for changes, the impacts of bridge construction and Hongdao Island connected to the land or not are also considered. A constant horizontal mixing coefficient is used in all cases, for eliminating the potential effects of numerical grids. The results show that the water exchange ability has generally decreased in JZB since 1935 to 2013, especially at the top of the bay. The bridge construction has only limited effects on water exchange, whereas Honngdao Island disconnection from land can help enhance water exchange.