Comprehensive large-scale investigation and assessment of trace metal in the coastal sediments of Bohai Sea

Abstract

The Bohai Sea is characterized as a semi-closed sea with limited water exchange ability, which has been regarded as one of the most contaminated regions in China and has attracted public attention over the past decades. In recent years, the rapid industrialization and urbanization around the coastal region has resulted in a severe pollution pressure in the Bohai Sea. Although efforts from official government and scientific experts have been made to protect and restore the marine ecosystem, satisfactory achievements were not gained. Moreover, partial coastal areas in the Bohai Sea seemingly remain heavily polluted. In this study, we focused on five coastal regions around the Bohai Sea to study the spatial distribution pattern of trace elements in the sediments and their ecological risk. A total of 108 sediment samples were analyzed to determine the contamination degree of trace elements (Cu, Cd, As, Pb, Zn, Cr, and Hg). Contamination factor (CF), pollution load index (PLI), geoaccumulation index (I), and potential ecological risk index (PERI) were utilized to assess the pollution extent of these metals. Spatial distribution patterns revealed that the sedimentary environments of coastal Bohai were in good condition, except Jinzhou Bay, according to the Marine Sediment Quality of China. The concentrations of Hg and Cd were considerably higher than the average upper crust value and presented high potential ecological risk and considerable potential ecological risk, respectively. The overall environment quality of the coastal Bohai Sea does not seem to pose an extremely serious threat in terms of metal pollution. Thus, the government should continue implementing pollution control programs in the Bohai Sea.

Distribution and risk assessment of trace metals in riverine surface sediments in gold mining area

“…Therefore, the potential risk decreased in the following order: Hgs > Cd > As > Cu > Pb > Cr/Zn. The results were in accordance with previous research, indicating that the sediment pollution of trace metals in the river occurred downstream as far as the adjacent area of the Bohai Sea (Li et al 2018;Zhang et al 2014).…”

Anthropogenic pollutant-driven geographical distribution of mesozooplankton communities in estuarine areas of the Bohai Sea, China

“…4. Our observations are in agreement with recent studies which have demonstrated that the differences in land-use largely contribute to changes in pollutant variables in aquatic systems 29,36,40 . Hence, the understanding of anthropogenic pollutions induced by different land-use would provide insights into the management of aquatic resource.…”

“…Those observations highlighted the differences in their surrounding land-use. A high level of heavy metal pollution was noted in Jinzhou Bay which was characterized with a high level of Cd, As and Hg pollutions in this investigation, mainly due to wastewater discharge by surrounding mining industries in the past century 36 . The organic pollutant concentrations in marine water columns were found to be generally high for Bohai Bay, with high COD being found in the Bohai Bay sampling stations because of sewage discharge from the big cities (Beijing and Tianjin) 38,39 .…”

“…The pollution levels varied among the coastal estuaries of Bohai Sea, especially for heavy metal pollutions 3,34–37 . For example, Jinzhou Bay, which is surrounded by one of the old industrial bases in China, was found with the highest concentrations of Cd, the pollution levels gradually decreased along Jinzhou Bay, Luanhekou Estuary, Laizhou Bay, Shuangtaizi Estuary and Bohai Bay 36 . Thus, the environmental gradients along the coastal bays or estuaries provide premise conditions for the exploration of ecological response of zooplankton under anthropogenic stress.…”

Evaluation of metal pollution-induced biological effects in Chinese shrimp Fenneropenaeus chinensis by NMR-based metabolomics

“…Therefore, this species has a great economic value in marine aquaculture (Song et al, 2018). However, metal pollution in the Bohai Sea resulting from industrial discharges has been a concerning issue (Gao et al, 2014;Li et al, 2018a). Unfortunately, there is little information regarding the metal concentrations in the muscle tissues of F. chinensis in the Bohai Sea.…”