Metal contamination in sediments of the western Bohai Bay and adjacent estuaries, China
Introduction
Rapid economic growth in coastal China has resulted in environmental degradation, habitat loss and alteration, and has placed new pressures on the nation’s coastal resources (Zhang et al., 2007, Zhang et al., 2009, Feng et al., 2008). Heavily industrialized, China’s third largest urban center Tianjin, has not been immune to these issues (Ye, 1991, Fan, 1992). Historically, the city served as the “gateway” to Beijing and was considered the most important industrial center in northern China (Chang et al., 1992). While that status had eroded over time, the recent renewal of the Beijing–Tianjin metropolitan corridor has done much to improve the economic status of northern China and the surrounding Bohai Region (Wei and Jia, 2003). Part of the newly created infrastructure, the Port of Tianjin, the largest in nation, has a constructed surface area of 0.6 km2 and a shoreline of 125 km, and is a designated national “hub” for international trade (Wei and Jia, 2003, Lu et al., 2009). The adjacent Bohai Sea serves as the receiving waters for about 36% of the wastewater and 47% of the solid pollutants released in China (Wang and Wang, 2007). Its 16000 km2 western most segment Bohai Bay, encompasses Tianjin, Hebei and Shandong provinces, and is one of the most important enclosed coastal seas in Asia (Ye, 1991). Rapid port expansion, new commercial development and urbanization along tributaries emptying into the Bay contribute pollutants to the receiving waters (Fan, 1992). Despite its assimilative capacity, Bohai Bay has experienced substantial water and sediment quality degradation in recent decades (Ye, 1991). For example, 1 × 109 tons of wastewater is discharged annually into the Bay exacerbating eutrophication, harmful algal blooms, and acute and chronic toxicity including instances of fish and shellfish mortality (Ye, 1991, Fan, 1992, Tao et al., 2001, Wang et al., 2004). Numerous persistent organic pollutants, and trace metals are also transported into this region through direct discharges and/or loading from adjacent tributaries (Wang and Wang, 2007).
Elevated concentrations of metals in estuarine sediments and organisms are a well-documented environmental concern (Timothy, 2000, Klimmek and Stan, 2001, Blackmore and Wang, 2004, Podgurskaya et al., 2004, Cheung and Wang, 2005, Cravo and Bebianno, 2005, Falco et al., 2006, Feng et al., 2008). Although there are indications that Bohai Bay has become increasingly contaminated with metals in the past 20 years (Zhao and Kong, 2000, Zhang, 2001), the available data are restricted to localized inshore areas and lack spatial resolution. There is need to expand the spatial and temporal coverage of sediment sampling in the area to better understand the transport and fate of these contaminants, and their potential ecosystem impacts for management purposes. Here, we report on trace metal (Ag, Cd, Cr, Cu, Ni, Pb and Zn) concentrations in sediments of western Bohai Bay, the urbanized Haihe and Yongding River estuaries, and the Port of Tianjin to assess the potential for metal impacts on the environment, and to examine trends in metal concentrations with time. A focused study of this type serves to inform decision-makers on the sources, transport and distribution of sediment associated contaminants and their potential ecological impacts in the region. The results will also be applicable to science-based policy formulation, and to ecosystem restoration/rehabilitation practices.
Section snippets
Field work
Sediment cores, ranging in length from 40 to 100 cm, were collected with a custom designed 10-cm inner diameter gravity corer fitted with prewashed polyethylene liners at 12 sampling stations in western Bohai Bay, and within the Port of Tianjin and the local estuaries of the Haihe and Yonding Rivers during July 24–26, 2007 (Fig. 1; Table 1). Once retrieved, all cores were sectioned into 2 cm increments for the first 20 cm, and at 5 cm intervals thereafter. The outer layer of each core section
Sediment metal concentrations
As expected, metal sediment concentrations at the 12 study area locations varied widely, with individual ranges recorded as: 2.22–4.14% for Fe; 0.194–2.10 mg kg−1 for Ag; 0.093–0.252 mg kg−1 for Cd; 38.2–79.8 mg kg−1 for Cr; 17.8–78.9 mg kg−1 for Cu; 26.5–45.4 mg kg−1 for Ni; 18.3–30.7 mg kg−1 for Pb; and 61.6–156 mg kg−1 for Zn, respectively (Table 3).
Contamination assessment
Metal enrichment factors (EF) were also broadly distributed: EFAg = 2.0–15; EFCd = 0.63–2.0; EFCr = 0.77–2.0; EFCu = 0.77–2.8; EFNi = 0.67–1.5;
Discussion
To reduce the potential for bias and to better characterize the likelihood for adverse environmental effects in western Bohai Bay and vicinity, several metrics for comparing risks to ecosystem health were adopted in this study: 1) sediment quality criteria (GB18668-2002), 2) metal enrichment factors (EF) and geoaccumulation index (Igeo), and 3) the effects range-low (ERL) guidelines (Müller, 1979, Müller, 1981, Sinex and Helz, 1981, Salomons and Forstner, 1984, Sinex and Wright, 1988, Long
Conclusions
We observed that sediment quality in western Bohai Bay and its adjacent coastal areas generally meets primary Chinese Marine Sediment Quality (GB 18668-2002) criteria. Potential impacts of metals in western Bohai Bay outside of the Port of Tianjin appeared to be low as judged by all three metrics employed in this study. The western Bohai Bay is generally unpolluted by Cd, Cr, Cu, Ni, Pb and Zn. However, the land-based anthropogenic impact on the coastal environment exists as suggested by the
Acknowledgements
This international collaborative research is jointly supported in part by US New Jersey Sea Grant (Project # 6560-0000, H. Feng) and China Tianjin Science and Technology Committee (Project # 06YFGHHZ01500). We would like to sincerely thank Captain Min Li and Firstmate Baoju Zhang of R/V Jihaiyu 1002 for their cooperation in the field work. Thanks are extended to Haiming Shi, JiangboTu and other scientific staff in Tianjin Marine Environmental Monitoring and Forecasting Center for their
References (84)
- et al.
The calculation of lead-210 dates assuming a constant rate of supply of unsupported 210Pb to the sediment
Catena
(1978) - et al.
Source of heavy metals in sediments of the Port Jackson estuary, Australia
Sci. Total Environ.
(1999) - et al.
The transfer of cadmium, mercury, methylmercury, and zinc in an intertidal rocky shore food chain
J. Exp. Mar. Biol. Ecol.
(2004) - et al.
Anthropogenic markers in the Holocene stratigraphic sequence of the Gulf of Trieste (northern Adriatic Sea)
Mar. Geol.
(2006) - et al.
Bioaccumulation of metals in the soft tissue of Patella aspera: application of metal/shell weight indices
Estuar. Coast. Shelf Sci.
(2005) - et al.
An assessment of metal contamination in coastal sediments of the Caspian Sea
Mar. Pollut. Bull.
(2004) Use of aluminum to normalize heavy-metal data from estuarine and coastal sediments of Straits of Melaka
Mar. Pollut. Bull.
(1992)- et al.
Deposition patterns of atmospheric 7Be and 210Pb in coast of East China Sea, Shanghai, China
Atmos. Environ.
(2008) - et al.
Distribution of heavy metal and PCB contaminants in the sediments of an urban estuary: the Hudson River
Mar. Environ. Res.
(1998) - et al.
A preliminary study of heavy metal contamination in Yangtze River intertidal zone due to urbanization
Mar. Pollut. Bull.
(2004)
Dredged material of IzmirHarbor: its behavior and pollution potential
Water Sci. Technol.
Metals in the sediments along the Hudson River estuary
Environ. Int.
Brick production with dredged harbour sediments. An industrial-scale experiment
Waste Manage.
Calculation and evaluation of sediment effect concentrations for the amphipod hyalella azteca and the midge Chironomus riparius
J. Great Lakes Res.
Multivariate statistical study of heavy metal enrichment in sediments of the Pearl River Estuary
Environ. Pollut.
Morphodynamic responses to the deep water harbor development in the Caofeidian sea area, China’s Bohai Bay
Coast. Eng.
Comparative advantages and limitations of the fallout radionuclides 137Cs, 210Pbex and 7Be for assessing soil erosion and sedimentation
J. Environ. Radioact.
Heavy metal pollution in Tianjin Bohai bay, China
J. Environ. Sci.
The use of Pb-210 geochronology as a sedimentological tool: application to the Washington continental shelf
Mar. Geol.
Distribution of trace metals in the sediments and biota of Chesapeake Bay
Mar. Pollut. Bull.
Distribution and normalization of heavy metal concentrations in mangrove and lagoonal sediments from Mazatlán Harbor (SE Gulf of California)
Estuar. Coast. Shelf Sci.
Spatial distribution of dissolved Pb, Hg, Cd, Cu and As in the Bohai sea
J. Environ. Sci.
Characterizing and comparing risks of polycyclic aromatic hydrocarbons in a Tianjin wastewater-irrigated area
Environ. Res.
The geographical foundations of local state initiatives: globalizing Tianjin, China
Cities
Multivariate analysis of heavy metal contamination in urban dusts of Xi’an
Cent. China. Sci. Total Environ.
Vessel-related contamination of Southern California by copper and other metals
Mar. Pollut. Bull.
Development of an integrated model for assessing the impact of diffuse and point source pollution on coastal waters
Environ. Modell. Softw.
Riverine composition and estuarine geochemistry of particulate metals in China-weathering feartures, anthropogenic impact and chemical fluxes
Estuar. Coast. Shelf Sci.
Heavy metal contamination in western Xiamen Bay sediments and its vicinity, China
Mar. Pollut. Bull.
Heavy metal contamination in surface sediments of Yangtze River intertidal zone: an assessment from different indexes
Environ. Pollut.
210Pb dating by low background gamma counting
Hydrobiologia
Contamination of the Hudson River - The Sediment Record
Tianjin: north China’s reviving metropolis
Influence of subcellular metal compartmentalization in different prey on the transfer of metals to a predatory gastropod
Mar. Ecol.-Prog. Ser.
The People’s Republic of China National Standards GB 18668-2002-Marine Sediment Quality
Normalization and elemental sediment contamination in the coastal United States
Environ. Sci. Technol.
Daily intake of arsenic, cadmium, mercury, and lead by consumption of edible marine species
J. Agr. Food Chem.
Bohai Bay in big trouble
Mar. Pollut. Bull.
Chapter 9. Heavy metal contamination in selected urban coastal regions in US and China
Short- and long-term sediment transport in western Bohai Bay and coastal areas
Chin. J. Oceanol. Limn
Evidence of urban source metal contaminants in NY/NJ Harbor
Middle States Geographers
Synthesis of water, sediment, and biological data using hazard quotients to assess ecosystem health, chap. C
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