防城港红树林湿地沉积物重金属分布特征及生态风险评价OA北大核心CHSSCDCSTPCD

[Objective]To explore the pollution level of heavy metals in mangrove sediments in Fangchenggang,assess the potential ecological risk and analyze the sources of heavy metals,so as to provide reference for the protection and pollution prevention of mangrove wetlands.[Method]By measuring the heavy metal content in the sediments of the study area,the level of heavy metal content was analyzed,and the cumulative index method and pollution load index method were used to evaluate the degree of heavy metal pollution.The potential ecological risk index method was used to comprehensively evaluate the potential ecological risk of heavy metals,and the PCA-MRL model was used for quantitative traceability of heavy metals.[Result and Conclusion]The average concentrations of Cu,Pb,Zn,Cd,As,and Hg in mangrove sediment in the study area were 20.40,18.50,52.20,0.09,11.95,and 0.036 μg·g-1,compared with other typical mangrove distribution areas in China,the heavy metal content in mangrove wetlands in the study area is relatively low.The pollution evaluation shows that there is slight or higher degree of pollution in most of the stations,and the polluted stations are mostly distributed in areas with relatively intensive human activities.The ecological risk assessment shows that the elements that cause potential ecological hazards are mainly Cd and Hg.Through PCA-MLR model analysis,it is found that Zn,Cd,and Pb mainly come from wastewater discharge from industrial and agricultural sources;As and Hg mainly come from the marine aquaculture industry;Cu mainly comes from the shipping industry.The relative contribution rates of the three sources are 46.25%,27.09%,and 26.66%.