As the second largest freshwater lake in China, Taihu Lake provides water supply to approximately 32 million inhabitants around the lake. However, dramatically increased pollution has threatened the safety of drinking...As the second largest freshwater lake in China, Taihu Lake provides water supply to approximately 32 million inhabitants around the lake. However, dramatically increased pollution has threatened the safety of drinking water supply in recent years. In the present study, we investigated the contaminations of nutrients and heavy metals in the sediments of an intake and inflow canals in Gonghu Bay, Taihu Lake. Moreover, we also examined the impact of human activities on spatial distribution char- acteristics of contaminations. Our results showed that the intake presented relatively lower concentrations of phos- phorus and nitrogen compared with inflow canals. However, the concentrations of Cr, Ni, Cu, Zn and Pb in the sediments of the intake exceeded the lowest effect level (LEL) values, indicating a potential risk to drinking water resource. In addition, the concentrations of Ni in the sediments of Tianji Canal and Jinshu Canal exceeded the severe effect level (SEL) value. More importantly, the concentrations of Cu in the sediments of Tianji Canal exceeded three times of the SEL value. Multivariate statistical analysis confirmed that the domestic sewage primarily contributed to the nutrient accumulation, and the leakage of electronic trash dominated the enrichment of metals in the sediments. Taken together, more effort should be made to ensure the security of water resources in Taihu Lake, especially for the treatment of domestic sewage and industrial wastewater.展开更多
In order to examine the intensity of surfi-cial sediment resuspension in Lake Taihu, a large shallow lake in eastern China, suspended sediment concentrations (SSCs) were measured on the basis of analysis of water samp...In order to examine the intensity of surfi-cial sediment resuspension in Lake Taihu, a large shallow lake in eastern China, suspended sediment concentrations (SSCs) were measured on the basis of analysis of water samples collected using an in-novative multi-level water sampler. The results show that under calm weather conditions, the SSC is rela-tively homogenous through the entire water column. However, when strong winds occur, the SSC in the bottom layer is 1-2 orders of magnitude greater than in the surface layer; thus, in this case, the amount of total suspended matter in the water column cannot be estimated using the SSC values of the surface layer alone. Furthermore, the depth of disturbance, or the thickness of the sediment layer that is set in mo-tion by wind-wave induced currents, is of the order of 100 mm.展开更多
文摘As the second largest freshwater lake in China, Taihu Lake provides water supply to approximately 32 million inhabitants around the lake. However, dramatically increased pollution has threatened the safety of drinking water supply in recent years. In the present study, we investigated the contaminations of nutrients and heavy metals in the sediments of an intake and inflow canals in Gonghu Bay, Taihu Lake. Moreover, we also examined the impact of human activities on spatial distribution char- acteristics of contaminations. Our results showed that the intake presented relatively lower concentrations of phos- phorus and nitrogen compared with inflow canals. However, the concentrations of Cr, Ni, Cu, Zn and Pb in the sediments of the intake exceeded the lowest effect level (LEL) values, indicating a potential risk to drinking water resource. In addition, the concentrations of Ni in the sediments of Tianji Canal and Jinshu Canal exceeded the severe effect level (SEL) value. More importantly, the concentrations of Cu in the sediments of Tianji Canal exceeded three times of the SEL value. Multivariate statistical analysis confirmed that the domestic sewage primarily contributed to the nutrient accumulation, and the leakage of electronic trash dominated the enrichment of metals in the sediments. Taken together, more effort should be made to ensure the security of water resources in Taihu Lake, especially for the treatment of domestic sewage and industrial wastewater.
文摘In order to examine the intensity of surfi-cial sediment resuspension in Lake Taihu, a large shallow lake in eastern China, suspended sediment concentrations (SSCs) were measured on the basis of analysis of water samples collected using an in-novative multi-level water sampler. The results show that under calm weather conditions, the SSC is rela-tively homogenous through the entire water column. However, when strong winds occur, the SSC in the bottom layer is 1-2 orders of magnitude greater than in the surface layer; thus, in this case, the amount of total suspended matter in the water column cannot be estimated using the SSC values of the surface layer alone. Furthermore, the depth of disturbance, or the thickness of the sediment layer that is set in mo-tion by wind-wave induced currents, is of the order of 100 mm.