Study on Nitrogen and Phosphorous Pollution Status in the Offshore Area of the Eastern Laizhou Bay

Based on an environmental survey in the offshore area of eastern Laizhou Bay in May, August, and October of 2016 to 2020, the pollutions of dissolved inorganic nitrogen and reactive phosphate were analyzed and evaluated. The results showed that the dissolved inorganic nitrogen(DIN) in this area had obvious seasonal variations and the concentration of DIN in May and October were higher than that in August. Because of the poor water exchange in this sea area and other reasons,the concentrations of different monitoring sites in May and October were different. The pollutions of reactive phosphate in the offshore area were more serious than that in the center of Laizhou Bay. The pollutions of reactive phosphate were proportional to rainfall in this area. The surface runoff had a significant effect on the concentration of reactive phosphate in this area.