To examine the status and risk of heavy metal pollution in urban lakes, in China, the distribution of several heavy metals (e.g., Cr,
Cu, Ni, Pb, Zn) in the sediment of Moshui Lake, Hangyang District, Wuhan City, was characterized. The process of rapid urbanization
and industrialization of the district was also studied to find out its relationship with the metal accumulation profile in the sediment. It
was found that the total concentration of heavy metals in the sediment was higher than the severe e ect level (SEL), at all sampling
sites, except those in the riparian zone. The Cr and Cu maximum concentrations were 1,780 and 1,250 mg/kg, approximately 16 and
11 times as much as the SEL values, and they appeared as deep as 32 cm in one sample. The carbonate and exchangeable fractions of
Zn were more than 50% of the total Zn content, resulting in very high risk according to the Risk Assessment Code (RAC). For Cu and
Ni, a medium RAC value was found for carbonate and exchangeable fractions of 11%–20%. As sensitive indicators of contaminants
in aquatic systems, heavy metals in the sediment reflect the outcome of regional urbanization, industrialization, and environmental
management. With rapid urbanization, sedimentary Pb and Zn concentrations increased. The experimental results showed that high
sedimentary heavy metal concentrations had resulted from rapid urbanization and industrialization, which would absolutely lead to
substantial aquatic environmental decline in urban lakes. 相似文献
Environmental Science and Pollution Research - To investigate the change in biochar’s ability to directly immobilize Cd in soil, a successive wheat cultivation experiment was conducted. Three... 相似文献
As an ubiquitous carcinogen, polycyclic aromatic hydrocarbons (PAHs) are closely related to anthropogenic activities. The process of urbanization leads to the spatial interlacing of farmlands and urbanized zones. However, field evidence on the influence of urbanization on the accumulation of PAHs in crops of peri-urban farmlands is lacking. This study comparatively investigated the urbanization-driven levels, compositions, and sources of PAHs in 120 paired plant and soil samples collected from the Yangtze River Delta in China and their species-specific human intake risks. The concentrations of PAHs in crops and soils in the peri-urban areas were 2407.92 ng g?1 and 546.64 ng g?1, respectively, which are significantly higher than those in the rural areas. The PAHs in the root were highly relevant to those in the soils (R2?=?0.63, p?<?0.01), and the root bioconcentration factors were higher than 1.0, implying the contributions of root uptake to plant accumulations. However, the translocation factors in the peri-urban areas (1.57?±?0.33) were higher than those in the rural areas (1.19?±?0.14), indicating the enhanced influence through gaseous absorption. For the congeners, the 2- to 3-ring PAHs showed a higher plant accumulation potential than the 4- to 6-ring PAHs. Principal component analysis show that the PAHs in the peri-urban plants predominantly resulted from urbanization parameters, such as coal combustion, vehicle emissions, and biomass burning. The mean values of estimated dietary intake of PAHs from the consumption of peri-urban and rural crops were 9116 ng day?1 and 6601.83 ng day?1, respectively. The intake risks of different crops followed the order rice?>?cabbage?>?carrot?>?pea. Given the significant input of PAHs from urban to farmland, the influence of many anthropogenic pollutants arising from rapid urbanization should be considered when assessing the agricultural food safety.
