The occurrence, toxicities, and ecological risks of five heavy metals(Pb, Cu, Cd, Zn and Ni) in the sediment of Taihu Lake were investigated in this study. To evaluate the toxicities caused by the heavy metals, the to...The occurrence, toxicities, and ecological risks of five heavy metals(Pb, Cu, Cd, Zn and Ni) in the sediment of Taihu Lake were investigated in this study. To evaluate the toxicities caused by the heavy metals, the toxicities induced by organic contaminants and ammonia in the sediments were screened out with activated carbon and zeolite. The toxicities of heavy metals in sediments were tested with benthic invertebrates(tubificid and chironomid).The correlations between toxicity of sediment and the sediment quality guidelines(SQGs)derived previously were evaluated. There were significant correlations(p < 0.0001) between the observed toxicities and the total risk quotients of the heavy metals based on SQGs,indicating that threshold effect level(TEL) and probable effect level(PEL) were reliable to predict the toxicities of heavy metals in the sediments of Taihu Lake. By contrast, the method based on acid volatile sulfides(AVS) and simultaneously extracted metals(SEM),such as ∑SEM/AVS and ∑SEM-AVS, did not show correlations with the toxicities. Moreover,the predictive ability of SQGs was confirmed by a total predicting accuracy of 77%. Ecological risk assessment based on TELs and PELs showed that the contaminations of Pb, Cu, Cd and Zn in the sediments of Taihu Lake were at relatively low or medium levels. The risks caused by heavy metals in the sediments of northern bay of the lake, which received more wastewater discharge from upper stream, were higher than other area of the lake.展开更多
Heavy metal contents along the Northwest coast of Sabah were determined to interpret the pollution level in the marine sediment. The metal abundance is regulated by the physico-chemical properties such as the average ...Heavy metal contents along the Northwest coast of Sabah were determined to interpret the pollution level in the marine sediment. The metal abundance is regulated by the physico-chemical properties such as the average sediment pH(7.82, 9.00 and 8.99), organic matter(0.62%, 1.60%, and 2.27%), moisture content(25.00%, 29.70%, and 15.00%) and sandy texture in Kota Belud, Kudat and Mantanani Island,respectively. The major elements show Ca>Fe>Mg>Al>Mn for all study sites, while the heavy metals show Ni>Cr>Zn>Cu>Co>Pb, Cr>Ni>Zn>Cu>Pb>Co and Zn>Pb>Cr>Ni, for Kota Belud, Kudat and Mantanani Island, respectively. The pollution degree of heavy metals was evaluated by using the Sediment Quality Assessment(SQA). The SQA parameters indicated none to moderate pollution in Kota Belud that shows Class 0, Class 1 and Class 2 pollution. The parameters also indicated none to low pollution in Kudat and Mantanani Island that show only Class 0 pollution. The enrichment factor(EF) suggested minor to moderately severe metal enrichment by anthropogenic sources in Kota Belud, whereas only minor enrichment in Kudat and Mantanani Island. The modified pollution degree(MCD<1.5) and pollution load index(0 PLI<1) indicating only low pollution level in the marine sediments for all study sites. The objectives of this study are:(1) to determine the physico-chemical parameters of sediments,(2) interpret the heavy metal contents and(3) evaluate the sediment quality.展开更多
Small-scale gold mining is linked to significant environmental pollution by potentially toxic elements (PTEs). However, research on the pollution caused by such mining activities remains insufficient especially in dev...Small-scale gold mining is linked to significant environmental pollution by potentially toxic elements (PTEs). However, research on the pollution caused by such mining activities remains insufficient especially in developing countries. In the present study, a systematic investigation assessed the pollution and level of ecological risk of PTEs in soil and stream sediments in an active small scale gold mining area of Isanga, in Nzega, Tanzania. Samples amounting to 16 soil and 20 sediment were gathered from the study area and analyzed for five PTEs concentrations (As, Cd, Cr, Hg and Pb) using the AAS method. The contamination level and ecological risk were assessed using several pollution indices. The results suggest that the assessed environmental systems of the Isanga mining area and its vicinities are lowly contaminated by PTEs and have a low potential to pose ecological risks. Hg and Cd with mean concentrations of 0.09 mg/kg and 0.26 mg/kg respectively were found to be the most enriched PTEs in soil, compared to their average continental crust concentrations (0.056 mg/kg and 0.102 mg/kg respectively). The levels of the evaluated PTEs in the study area are susceptible to increase over time if proactive steps are not taken to control mining and waste disposal activities.展开更多
In this paper,25 sampling points of overlying deposits in Tonglushan mining area,Daye City,Hubei Province,China were tested for heavy metal content to explore pollution characteristics,pollution sources and ecological...In this paper,25 sampling points of overlying deposits in Tonglushan mining area,Daye City,Hubei Province,China were tested for heavy metal content to explore pollution characteristics,pollution sources and ecological risks of heavy metals in sediments.A geo-accumulation index method was used to evaluate the degree of heavy metal pollution in the sediment.The mean sediment quality guideline quotient was used for evaluating the ecological risk level of heavy metal in the sediment.And a method of correlation analysis,clustering analysis,and principal component analysis was used for preliminary analysis on the source of heavy metal in the sediment.It was indicated that there was extremely heavy metal pollution in the sediment,among which Cd was extremely polluted,Cu strongly contaminated,Zn,As,and Hg moderately contaminated,and Pb,Cr,and Ni were slightly contaminated.It was also indicated by the mean sediment quality guideline-quotient result that there was a high ecological risk of heavy metals in the sediment,and 64%of the sample sites had extremely high hidden biotoxic effects.For distribution,the contamination of branches was worse than that of the main channel of Daye Dagang,and the deposition of each heavy metal was mainly influenced by the distance from this sample site to the sewage draining exit of a tailings pond.The source analysis showed that the heavy metals in the sediment come from pollution discharging of mining and beneficiation companies,tailings ponds,smelting companies,and transport vehicles.In the study area,due to the influence of heavy metal discharging from these sources,the ecotoxicity of heavy metals in the sediment was extremely high,and Cd was the most toxic pollutant.The research figured out the key restoration area and elements for ecological restoration in the sediment of the Tonglüshan mining area,which could be referenced by monitoring and governance of heavy metal pollution in the sediment of the polymetallic mining area.展开更多
<p class="MsoNormal" style="font-size:medium;white-space:normal;"> <p class="MsoNormal" style="text-align:justify;font-size:medium;white-space:normal;"> <span lan...<p class="MsoNormal" style="font-size:medium;white-space:normal;"> <p class="MsoNormal" style="text-align:justify;font-size:medium;white-space:normal;"> <span lang="EN-US"><span style="font-family:Verdana;font-size:12px;">Distribution patterns of selected heavy metals content in sediments from the Bay of Quiberon and Gulf of Morbihan were studied to understand the current heavy metals contamination due to urbanization and mariculture activities in the coastal area. Therefore, a survey was conducted and 196 sediments collected were characterized for heavy metals content using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) after mix acid digestion process. The distribution maps of the concentrations of the heavy metals studied were produced as an isopleth map based on data interpolation by the ArcGIS software application. The association with the adverse effects on aquatic organisms was determined by the classification of the sediment according to the sediment quality guidelines. Therefore, two approaches were employed namely: direct comparison with Sediment Quality Guidelines (SQGs) by USEPA (United States Environmental Protection Agency) and comparison with other numerical SQGs, threshold effect level/probable effect level, and effect range low/effect range medium. In order to estimate the effect of multiple contaminations of heavy metals, the mean-ERM-quotient was calculated at each sampling point.</span><o:p></o:p></span> </p> <span style="font-family:Verdana;font-size:12px;"> <div style="text-align:justify;"> </div> </span> </p>展开更多
This study was to evaluate the effect of stocking densities on the nitrogen and phosphorus budgets for a polyculture of the crab Portunus trituberculatus and the Pacific white shrimp Litopenaeus vannamei.The shrimps(i...This study was to evaluate the effect of stocking densities on the nitrogen and phosphorus budgets for a polyculture of the crab Portunus trituberculatus and the Pacific white shrimp Litopenaeus vannamei.The shrimps(initial weight,0.012 g)were cultured at a density of 45 shrimp m^(-2),and juvenile crabs(initial weight,0.024 g)were cultured at five densities of 0,3,6,9,and 12 crabs m^(-2).The treatments were grouped as C0S45,C3S45,C6S45,C9S45,and C12S45,respectively.Water quality parameters,growth of shrimp and crabs,and nitrogen and phosphorus budget were measured.The results indicated that the shrimp performances in polyculture treatments C3S45 and C6S45 were superior to those in the crab-free treatment(C0S45).The crab in treatments C3S45 and C6S45 exhibited a significantly higher final mean weight and carapace width/length than those in treatments C9S45 and C12S45.The final size and survival of crabs had a negative correlation with the increasing crab stocking density.The contents of total phos-phorus and total nitrogen and the comprehensive contamination index values were higher in the C9S45 and C12S45 treatments than in the other treatments.The conversion ratios of nitrogen for crab and shrimp growth in treatment C3S45 were significantly higher than those in the crab-free treatment.These findings indicate that polyculturing shrimp with crabs at suitable densities can improve productivity,profitability,nutrient utilization,and the environmental quality.From the 60-day treatments,the optimal culture densi-ties were 3-6 crabs m^(-2) and 45 shrimps m^(-2).展开更多
Polycyclic aromatic hydrocarbons(PAHs),as persistent toxic substances(PTS),have been widely monitored in coastal environment,including seawater and sediment.However,scientific monitoring methods,like ecological risk a...Polycyclic aromatic hydrocarbons(PAHs),as persistent toxic substances(PTS),have been widely monitored in coastal environment,including seawater and sediment.However,scientific monitoring methods,like ecological risk assessment and integrated biomarker response,still need massive researches to verify their availabilities.This study was performed in March,May,August and October of 2018 at eight sites,Yellow River estuary(S1),Guangli Port(S2),Xiaying(S3),Laizhou(S4),Inner Bay(S5),Outer Bay(S6),Hongdao(S7)and Hongshiya(S8)of Shandong Peninsula,China.The contents of 16 priority PAHs in local seawater and sediment were determined,by which ecological risk assessment risk quotient(RQ)for seawater and sediment quality guidelines(SQGs)were calculated to characterize the PAHs pollution.Meanwhile,multiple biomarkers in the digestive gland of clam Ruditapes philippinarum were measured to represent different biological endpoints,including ethoxyresorufin-O-deethylase(EROD),glutathione S-transferase(GST),sulfotransferase(SULT),superoxide dismutase(SOD)and lipid peroxidation(LPO),by which integrated biomarker response(IBR)was calculated to provide a comprehensive assessment of environmental quality.Taken together,these results revealed the heaviest pollution at S2 as both PAHs concentrations and biomarkers responses reflected,and supported the integrated biomarker response as a useful tool for marine environmental monitoring,through its integration with SQGs.展开更多
基金supported by the Ministry of Science and Technology(No.2012ZX07501-003-04)the National Natural Science Foundation of China(NSFC)(Nos.21325730,21577067,46103095)
文摘The occurrence, toxicities, and ecological risks of five heavy metals(Pb, Cu, Cd, Zn and Ni) in the sediment of Taihu Lake were investigated in this study. To evaluate the toxicities caused by the heavy metals, the toxicities induced by organic contaminants and ammonia in the sediments were screened out with activated carbon and zeolite. The toxicities of heavy metals in sediments were tested with benthic invertebrates(tubificid and chironomid).The correlations between toxicity of sediment and the sediment quality guidelines(SQGs)derived previously were evaluated. There were significant correlations(p < 0.0001) between the observed toxicities and the total risk quotients of the heavy metals based on SQGs,indicating that threshold effect level(TEL) and probable effect level(PEL) were reliable to predict the toxicities of heavy metals in the sediments of Taihu Lake. By contrast, the method based on acid volatile sulfides(AVS) and simultaneously extracted metals(SEM),such as ∑SEM/AVS and ∑SEM-AVS, did not show correlations with the toxicities. Moreover,the predictive ability of SQGs was confirmed by a total predicting accuracy of 77%. Ecological risk assessment based on TELs and PELs showed that the contaminations of Pb, Cu, Cd and Zn in the sediments of Taihu Lake were at relatively low or medium levels. The risks caused by heavy metals in the sediments of northern bay of the lake, which received more wastewater discharge from upper stream, were higher than other area of the lake.
基金supported by the Ministry of Higher Education of Malaysia for University Malaysia Sabah under the research grant TR@M001-2019。
文摘Heavy metal contents along the Northwest coast of Sabah were determined to interpret the pollution level in the marine sediment. The metal abundance is regulated by the physico-chemical properties such as the average sediment pH(7.82, 9.00 and 8.99), organic matter(0.62%, 1.60%, and 2.27%), moisture content(25.00%, 29.70%, and 15.00%) and sandy texture in Kota Belud, Kudat and Mantanani Island,respectively. The major elements show Ca>Fe>Mg>Al>Mn for all study sites, while the heavy metals show Ni>Cr>Zn>Cu>Co>Pb, Cr>Ni>Zn>Cu>Pb>Co and Zn>Pb>Cr>Ni, for Kota Belud, Kudat and Mantanani Island, respectively. The pollution degree of heavy metals was evaluated by using the Sediment Quality Assessment(SQA). The SQA parameters indicated none to moderate pollution in Kota Belud that shows Class 0, Class 1 and Class 2 pollution. The parameters also indicated none to low pollution in Kudat and Mantanani Island that show only Class 0 pollution. The enrichment factor(EF) suggested minor to moderately severe metal enrichment by anthropogenic sources in Kota Belud, whereas only minor enrichment in Kudat and Mantanani Island. The modified pollution degree(MCD<1.5) and pollution load index(0 PLI<1) indicating only low pollution level in the marine sediments for all study sites. The objectives of this study are:(1) to determine the physico-chemical parameters of sediments,(2) interpret the heavy metal contents and(3) evaluate the sediment quality.
文摘Small-scale gold mining is linked to significant environmental pollution by potentially toxic elements (PTEs). However, research on the pollution caused by such mining activities remains insufficient especially in developing countries. In the present study, a systematic investigation assessed the pollution and level of ecological risk of PTEs in soil and stream sediments in an active small scale gold mining area of Isanga, in Nzega, Tanzania. Samples amounting to 16 soil and 20 sediment were gathered from the study area and analyzed for five PTEs concentrations (As, Cd, Cr, Hg and Pb) using the AAS method. The contamination level and ecological risk were assessed using several pollution indices. The results suggest that the assessed environmental systems of the Isanga mining area and its vicinities are lowly contaminated by PTEs and have a low potential to pose ecological risks. Hg and Cd with mean concentrations of 0.09 mg/kg and 0.26 mg/kg respectively were found to be the most enriched PTEs in soil, compared to their average continental crust concentrations (0.056 mg/kg and 0.102 mg/kg respectively). The levels of the evaluated PTEs in the study area are susceptible to increase over time if proactive steps are not taken to control mining and waste disposal activities.
基金jointly supported by the Gansu Provincial Natural Resources Science and Technology Project of the Key Laboratory of Strategic Mineral Resources of the Upper Yellow River,Ministry of Natural Resources(YSJD2022-16)the survey project initiated by the China Geological Survey(DD20211347).
文摘In this paper,25 sampling points of overlying deposits in Tonglushan mining area,Daye City,Hubei Province,China were tested for heavy metal content to explore pollution characteristics,pollution sources and ecological risks of heavy metals in sediments.A geo-accumulation index method was used to evaluate the degree of heavy metal pollution in the sediment.The mean sediment quality guideline quotient was used for evaluating the ecological risk level of heavy metal in the sediment.And a method of correlation analysis,clustering analysis,and principal component analysis was used for preliminary analysis on the source of heavy metal in the sediment.It was indicated that there was extremely heavy metal pollution in the sediment,among which Cd was extremely polluted,Cu strongly contaminated,Zn,As,and Hg moderately contaminated,and Pb,Cr,and Ni were slightly contaminated.It was also indicated by the mean sediment quality guideline-quotient result that there was a high ecological risk of heavy metals in the sediment,and 64%of the sample sites had extremely high hidden biotoxic effects.For distribution,the contamination of branches was worse than that of the main channel of Daye Dagang,and the deposition of each heavy metal was mainly influenced by the distance from this sample site to the sewage draining exit of a tailings pond.The source analysis showed that the heavy metals in the sediment come from pollution discharging of mining and beneficiation companies,tailings ponds,smelting companies,and transport vehicles.In the study area,due to the influence of heavy metal discharging from these sources,the ecotoxicity of heavy metals in the sediment was extremely high,and Cd was the most toxic pollutant.The research figured out the key restoration area and elements for ecological restoration in the sediment of the Tonglüshan mining area,which could be referenced by monitoring and governance of heavy metal pollution in the sediment of the polymetallic mining area.
文摘<p class="MsoNormal" style="font-size:medium;white-space:normal;"> <p class="MsoNormal" style="text-align:justify;font-size:medium;white-space:normal;"> <span lang="EN-US"><span style="font-family:Verdana;font-size:12px;">Distribution patterns of selected heavy metals content in sediments from the Bay of Quiberon and Gulf of Morbihan were studied to understand the current heavy metals contamination due to urbanization and mariculture activities in the coastal area. Therefore, a survey was conducted and 196 sediments collected were characterized for heavy metals content using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) after mix acid digestion process. The distribution maps of the concentrations of the heavy metals studied were produced as an isopleth map based on data interpolation by the ArcGIS software application. The association with the adverse effects on aquatic organisms was determined by the classification of the sediment according to the sediment quality guidelines. Therefore, two approaches were employed namely: direct comparison with Sediment Quality Guidelines (SQGs) by USEPA (United States Environmental Protection Agency) and comparison with other numerical SQGs, threshold effect level/probable effect level, and effect range low/effect range medium. In order to estimate the effect of multiple contaminations of heavy metals, the mean-ERM-quotient was calculated at each sampling point.</span><o:p></o:p></span> </p> <span style="font-family:Verdana;font-size:12px;"> <div style="text-align:justify;"> </div> </span> </p>
基金supported by the National Key Technology Research and Development Program of Chi-na for the Eleventh Five-Year Plan(No.2006BAD09A01).
文摘This study was to evaluate the effect of stocking densities on the nitrogen and phosphorus budgets for a polyculture of the crab Portunus trituberculatus and the Pacific white shrimp Litopenaeus vannamei.The shrimps(initial weight,0.012 g)were cultured at a density of 45 shrimp m^(-2),and juvenile crabs(initial weight,0.024 g)were cultured at five densities of 0,3,6,9,and 12 crabs m^(-2).The treatments were grouped as C0S45,C3S45,C6S45,C9S45,and C12S45,respectively.Water quality parameters,growth of shrimp and crabs,and nitrogen and phosphorus budget were measured.The results indicated that the shrimp performances in polyculture treatments C3S45 and C6S45 were superior to those in the crab-free treatment(C0S45).The crab in treatments C3S45 and C6S45 exhibited a significantly higher final mean weight and carapace width/length than those in treatments C9S45 and C12S45.The final size and survival of crabs had a negative correlation with the increasing crab stocking density.The contents of total phos-phorus and total nitrogen and the comprehensive contamination index values were higher in the C9S45 and C12S45 treatments than in the other treatments.The conversion ratios of nitrogen for crab and shrimp growth in treatment C3S45 were significantly higher than those in the crab-free treatment.These findings indicate that polyculturing shrimp with crabs at suitable densities can improve productivity,profitability,nutrient utilization,and the environmental quality.From the 60-day treatments,the optimal culture densi-ties were 3-6 crabs m^(-2) and 45 shrimps m^(-2).
基金supported by Shandong Provincial Department of Agriculture and Rural Affairs(No.20180163)the National Natural Science Foundation of China-Shandong Joint Fund for Marine Science Research Centers(No.20180165)。
文摘Polycyclic aromatic hydrocarbons(PAHs),as persistent toxic substances(PTS),have been widely monitored in coastal environment,including seawater and sediment.However,scientific monitoring methods,like ecological risk assessment and integrated biomarker response,still need massive researches to verify their availabilities.This study was performed in March,May,August and October of 2018 at eight sites,Yellow River estuary(S1),Guangli Port(S2),Xiaying(S3),Laizhou(S4),Inner Bay(S5),Outer Bay(S6),Hongdao(S7)and Hongshiya(S8)of Shandong Peninsula,China.The contents of 16 priority PAHs in local seawater and sediment were determined,by which ecological risk assessment risk quotient(RQ)for seawater and sediment quality guidelines(SQGs)were calculated to characterize the PAHs pollution.Meanwhile,multiple biomarkers in the digestive gland of clam Ruditapes philippinarum were measured to represent different biological endpoints,including ethoxyresorufin-O-deethylase(EROD),glutathione S-transferase(GST),sulfotransferase(SULT),superoxide dismutase(SOD)and lipid peroxidation(LPO),by which integrated biomarker response(IBR)was calculated to provide a comprehensive assessment of environmental quality.Taken together,these results revealed the heaviest pollution at S2 as both PAHs concentrations and biomarkers responses reflected,and supported the integrated biomarker response as a useful tool for marine environmental monitoring,through its integration with SQGs.
