The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in soil.Its spatial distribution and environment risk assessment are extremely important for the management and remediatio...The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in soil.Its spatial distribution and environment risk assessment are extremely important for the management and remediation of HMs.Eighty soil samples were collected from the high-sulfur CG site in northern China and analyzed for six HMs.The results showed that the soil was heavily contaminated by Mn,Cr and Ni based on the Nemerow index,and posed seriously ecological risk depended on the geo-accumulation index,potential ecological risk index and risk assessment code.The semi-variogram model and ordinary kriging interpolation accurately portrayed the spatial distribution of HMs.Fe,Mn,and Cr were distributed by band diffusion,Ni was distributed by core,the distribution of Cu had obvious patchiness and Zn was more uniform.The spatial autocorrelation indicated that all HMs had strong spatial heterogeneity.The BCR sequential extraction was employed to qualify the geochemical fractions of HMs.The data indicated that Fe and Cr were dominated by residual fraction;Cu,Ni and Zn were dominated by reducible and oxidizable fractions;Mn was dominated by reducible and acid-extractable(25.38%-44.67%)fractions.Pearson correlation analysis showed that pH was the main control factor affecting the non-residue fractions of HMs.Therefore,acid production from high sulfur CG reduced soil pH by 2-3,which indirectly promoted the activity of HMs.Finally,the conceptual model of HMs contamination at the CG site was proposed,which can be useful for the development of ecological remediation strategies.展开更多
To combat environmental pollution,a viable option is to adjust industrial structures to reduce the emissions of pollut-ants.One means to gauge the effects of such change is to assess the potential ecological risk of t...To combat environmental pollution,a viable option is to adjust industrial structures to reduce the emissions of pollut-ants.One means to gauge the effects of such change is to assess the potential ecological risk of the pollutants of anthro-pogenic origin.The present study examines an urbanized waterway in the Pearl River Delta(PRD)of China as the study region.This study aims to gauge the effects of such an industrial adjustment by assessing the state of pollution as well as related ecological risk in surface water and sediment caused by certain largely anthropogenically derived heavy metals(Cr,Ni,Cu,Zn,As,Cd,and Pb,which are the key heavy metal pollutants that need to be prevented and controlled as per the list in the 13th Five Year Plan for Comprehensive Prevention and Control of Heavy Metal Pollution in Guang-dong Province).The average concentrations of heavy metals in sediments were present in the order Zn>Cr>Cu>Pb>Ni>As>Cd and were all higher than baseline values.These concentrations increased in the period from 2008 to 2011,but declined from 2011 to 2018,which is consistent with the shift in local industrial structures from high pollutant-emitting industries to low ones.The results revealed that there was an overwhelming occurrence of Cr in the residual fraction,as it can be strongly bound to crystalline structures.Nickel and As also mainly occurred in the residual fraction.Zinc was chiefly bound to the reducible and residual fractions.Cadmium was primarily affiliated with the acid-soluble fraction,whereas Cu and Pb were mainly affiliated with the reducible fraction.These results suggest that the presence of Cu,Zn,Cd,and Pb was impacted more by human activities as compared to that of Cr,Ni,and As.Further,nickel was the most dominant contributor to ecological pollution in water,while Cd contributed the most to sediment pollution.Despite the tremendous efforts in adjusting industrial structures in the study region,potential ecological risks due to anthropo-genic activities has remained a threat to the aquatic environment and should be further reduced.展开更多
基金supported by the National Key R&D Program of China (No.2019YFC1805001)Open Foundation of State Key Laboratory of Mineral Processing (No.BGRIMM-KJSKL2022-07)。
文摘The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in soil.Its spatial distribution and environment risk assessment are extremely important for the management and remediation of HMs.Eighty soil samples were collected from the high-sulfur CG site in northern China and analyzed for six HMs.The results showed that the soil was heavily contaminated by Mn,Cr and Ni based on the Nemerow index,and posed seriously ecological risk depended on the geo-accumulation index,potential ecological risk index and risk assessment code.The semi-variogram model and ordinary kriging interpolation accurately portrayed the spatial distribution of HMs.Fe,Mn,and Cr were distributed by band diffusion,Ni was distributed by core,the distribution of Cu had obvious patchiness and Zn was more uniform.The spatial autocorrelation indicated that all HMs had strong spatial heterogeneity.The BCR sequential extraction was employed to qualify the geochemical fractions of HMs.The data indicated that Fe and Cr were dominated by residual fraction;Cu,Ni and Zn were dominated by reducible and oxidizable fractions;Mn was dominated by reducible and acid-extractable(25.38%-44.67%)fractions.Pearson correlation analysis showed that pH was the main control factor affecting the non-residue fractions of HMs.Therefore,acid production from high sulfur CG reduced soil pH by 2-3,which indirectly promoted the activity of HMs.Finally,the conceptual model of HMs contamination at the CG site was proposed,which can be useful for the development of ecological remediation strategies.
基金supported by the National Natural Science Foundation of Guangdong Province(No.2015B020237006).
文摘To combat environmental pollution,a viable option is to adjust industrial structures to reduce the emissions of pollut-ants.One means to gauge the effects of such change is to assess the potential ecological risk of the pollutants of anthro-pogenic origin.The present study examines an urbanized waterway in the Pearl River Delta(PRD)of China as the study region.This study aims to gauge the effects of such an industrial adjustment by assessing the state of pollution as well as related ecological risk in surface water and sediment caused by certain largely anthropogenically derived heavy metals(Cr,Ni,Cu,Zn,As,Cd,and Pb,which are the key heavy metal pollutants that need to be prevented and controlled as per the list in the 13th Five Year Plan for Comprehensive Prevention and Control of Heavy Metal Pollution in Guang-dong Province).The average concentrations of heavy metals in sediments were present in the order Zn>Cr>Cu>Pb>Ni>As>Cd and were all higher than baseline values.These concentrations increased in the period from 2008 to 2011,but declined from 2011 to 2018,which is consistent with the shift in local industrial structures from high pollutant-emitting industries to low ones.The results revealed that there was an overwhelming occurrence of Cr in the residual fraction,as it can be strongly bound to crystalline structures.Nickel and As also mainly occurred in the residual fraction.Zinc was chiefly bound to the reducible and residual fractions.Cadmium was primarily affiliated with the acid-soluble fraction,whereas Cu and Pb were mainly affiliated with the reducible fraction.These results suggest that the presence of Cu,Zn,Cd,and Pb was impacted more by human activities as compared to that of Cr,Ni,and As.Further,nickel was the most dominant contributor to ecological pollution in water,while Cd contributed the most to sediment pollution.Despite the tremendous efforts in adjusting industrial structures in the study region,potential ecological risks due to anthropo-genic activities has remained a threat to the aquatic environment and should be further reduced.
