Change laws of PHC contents in bottom waters in the bay mouth of Jiaozhou Bay

Abstract

Based on investigation data on petroleum hydrocarbon (PHC) in June, July, September and October 1980 in bottom waters in Jiaozhou Bay, we analyzed the content and distribution of PHC. Results showed that PHC contents in June, July, September and October 1980 in bottom waters were 0.028-0.147 mg L and were meeting Grade II (0.05 mg L) and III (0.30 mg L) in National Sea Water Quality Standard (GB 3097-1997). PHC contents were decreasing from the inside of the bay mouth to the bay mouth, and to the outside of the bay mouth in June, and were decreasing from the inside of the bay mouth to the open waters in September and October, yet were decreasing from the open waters to the inside of the bay mouth in July. We found that no matter from the bay to the open water of from the open water to the bay, the contents of the substances were decreasing continuously by means of vertical water’s effect. Introduction PHC has been widely used in industry and agriculture, and the PHC-containing waste water has caused the degrading of water quality in marine environment [1-5], and was harmful to human being finally. This paper analyzed the content and distribution of PHC in bottom waters in the bay mouth of Jiaozhou Bay based on investigation data on petroleum hydrocarbon (PHC) in June, July, September and October 1980, and revealed the change laws of PHC in waters, and provide scientific basis for the research on the existence and migration of PHC in marine bay. Material and method Jiaozhou Bay (35°55′-36°18′ N, 120°04′-120°23′ E) is a semi-closed bay located in the south of Shandong Province, eastern China (Fig. 1). The total area and bay mouth depth 446 km and 3 km, respectively. The bay has more than ten inflow rivers, including Haibo Rriver, Licun Rriver and Loushan Rriver etc., all of which have seasonal features [6-7]. The data was provided by North China Sea Environmental Monitoring Center. The survey was conducted in June, July, September and October 1980 (Fig. 1). PHC in bottom waters was sampled and monitored follow by National Specification for Marine Monitoring [8]. Results and discussion