Aquatic Environmental Chemistry of Intertidal Zone in Bohai Bay of Qinhuangdao

Based on the investigating the inter-tidal water environment in Qinhuangdao section, the distribution characteristics of ammonia nitrogen, chemical oxygen demand, Zn, Cd and other metal elements in the water body and the pollution characteristics of Cu, Pb, Zn and Cd in surface sediment were studied. The results showed that Cd, chemical oxygen demand and ammonia nitrogen are the main pollutants in the water body, and 100%, 90.9% and 54.5% of the sample sites exceeded the grade V of surface water environment quality standard, respectively. In surface sediments, Cd was the main pollutant and its average concentration was 5.6 times higher than the national secondary soil quality standard. These contaminants in inter-tidal waters may affect the quality of coastal water and marine organisms.