Distribution and Potential Ecological Risk Evaluation of Heavy Metals in Surface Sediments of Minjiang River Estuary

Abstract

In order to strengthen the environmental control of Minjiang River Basin and support the management and control of heavy metal pollution in Minjiang Estuary, based on the measured data of 14 sampling stations in Minjiang Estuary, this paper systematically evaluated the distribution of heavy metals and their potential ecological risks in surface sediments of Minjiang Estuary by using the methods of correlation analysis, principal component analysis and potential ecological risk index. The results showed that there were significant differences in the content of heavy metals in the surface sediments of Minjiang Estuary. Except for Zn and Hg at individual stations, the concentrations of other heavy metals were accorded with first class of the national marine sediment quality. The main factor affecting the distribution of lead was industrial sewage, while the main factors affecting the distribution of other heavy metals were organic matter and sedimentary environment. The proportion of low risk and medium risk of potential ecological risk of heavy metals in surface sediments of Minjiang Estuary was 71.43% and 28.57%, respectively. Among them, the east and south of Langqi Island were medium risk areas, and the north and northeast of Langqi Island and the outside of Chuanshi waterway were low risk areas. Cd and Hg were the main heavy metal elements with potential ecological risks, which had reached a high risk level, and risk monitoring work should be strengthened.

Keywords

• minjiang river estuary
• surface sediments
• heavy metals
• ecological risk
• land source pollution