Heavy metal pollution assessment in marine sediments in the Northwest coast of Sabah,Malaysia

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.

Effects of heavy metal pollution on farmland soils and crops:A case study of the Xiaoqinling Gold Belt,China

This paper focuses on the heavy metal enrichment and heavy metal pollution degree associated with mining activities in some crops and the soils of different parent materials in the Xiaoqinling Gold Belt.According to the geochemical analysis results of the soils observed in the gold belt,the soils are most highly enriched in Pb,followed by Cr,Cu,and Zn.Furthermore,they are relatively poor in Hg,Cd,and As.It is also shown that the heavy metals in all kinds of soils have the same geochemical characteristics in the gold belt.As for the crops(such as corn and wheat)in the gold belt,Zn and Cu are the most abundant elements,followed by Pb and Cr.Meanwhile,Hg,Cd,and As were found to have relatively low concentrations in the crops.The heavy metals in wheat and corn have the same geochemical characteristics in the gold belt in general.Compared to the aeolian loess soils and the crops therein,heavy metals are more enriched in diluvial and alluvial soils and the crops therein.As shown by relevant studies,the Hg,Pb,Cd,Cu,and Zn pollution are mainly caused by mining activities.Corn and wheat in the gold belt have a high tendency of risk exposure to heavy metal pollution since they are mostly affected by mining activities and feature high background values of heavy metal concentrations.Furthermore,wheat is more liable to be enriched in heavy metals than corn is grown in all types of soils.The Hg pollution in soils leads to Hg accumulation,increasing the risk of Hg uptake in crops,and further affecting human health.This study will provide a scientific basis for the control and management of heavy metals in farmland soils of mining areas.

Health Risks Assessment of Heavy Metal Pollution in the Soil-Crop System from an E-Waste Dismantling Area

Soil is an essential resource for agricultural production.In order to investigate the pollution situation of heavy metals in the soil-crop system in the e-waste dismantling area,the crop and soil samples(226 pairs,including leaf vegetables,solanaceous vegetables,root vegetables,and fruits)around the e-waste dismantling area in southeastern Zhejiang Province were collected.The concentrations of Cd,Cu,Pb,and Cr were determined.The average concentrations of Cd,Cu,Pb,and Cr in soils were 0.94,107.79,80.28,and 78.14 mg kg-1,respectively,and their corresponding concentrations in crops were 0.024,0.7,0.041,and 0.06 mg kg-1,respectively.The transfer capacity of leaf vegetables was significantly higher than that of non-leaf vegetables,and the accumulation of four heavy metals in crops tended to be Cd>Cu>Cr/Pb.The pollution index’s results revealed that the soil pollution degree under different land uses ranked as root vegetables soil>leaf vegetables soil>solanaceous vegetables soil>fruit soil.The carcinogenic and non-carcinogenic risks of heavy metal exposure were ranked as food intake>accidental ingestion>dermal contact>inhalation.The comprehensive non-carcinogenic risk was ranked as Cr>Cd>Pb/Cu.Our results could be used to provide useful information for further crop cultivation layout in the study area,which can guarantee the local residents’health and food safety.

The assessment of heavy metal pollution in river sands of Jalingo,Nigeria using magnetic proxy parameters,pollution,and ecotoxicological indices

The measurement of environmental magnetic properties and metal contents of sands from Nukkai(NKR),Mayo-Gwoi(RMYG)and Lamurde(LR)rivers located in Jalingo,Nigeria are reported.We seek to determine the extent of anthropogenic impact on the river sands using magnetic-proxy-parameters,pollution and ecotoxicological indices and multivariate statistics.Measurements of magnetic susceptibilityχ,frequency-dependentsusceptibilityχfd%,anhystericremanent magnetization,isothernal remanent magnetization and X-ray fluorescence were undertaken.The average values of theχ(in×10^(-8)m^(3)kg^(-1))were 24.53,12.76 and 39.27 for NKR,RMYG and LR sites respectively,implying that the magnetic minerals in the sands were mostly ferrimagnetic.The meanχfd%value of 2.64%,4.85%and 3.53%for NKR,RMYG and LR respectively suggest that the study area was dominated by multi-domain magnetic grain sizes.The value of the S-ratio is~1 in all river samples,suggesting that low coercivity magnetic minerals(e.g.,magnetite)dominated the samples.The mean concentrations of Ti,Zr,Sn,Ba and Pb were higher than the background values in the studied samples.All the estimated pollution indices puts the level of pollution of the river sands between low and moderate pollution with Sn,Ba and Pb as the elements of concern.Multiple sources of metal contents such as fertilizers,pesticides,waste dumps and vehicular sources etc.were found.Significant positive correlations between magnetic parameters(particularly,SIRM)and some heavy metals and pollution/ecotoxicological indices were obtained,showing that magnetic methods could be used as a geochemical proxy for pollution assessment.

A practical method for identifying key factors in the distribution and formation of heavy metal pollution at a smelting site

Smelting activities are the main pathway for the anthropogenic release of heavy metals(HMs)into the soil-groundwater environment.It is vital to identify the factors affecting HMs pollution to better prevent and manage soil pollution.The present study conducted a comprehensive investigation of HMs in soil from a large abandoned Zn smelting site.An integrated approach was proposed to classify and quantify the factors affecting HMs pollution in the site.Besides,the quantitative relationship between hydrogeological characteristics,pollution transmission pathways,smelting activities and HMs pollutionwas established.Results showed that the soils were highly contaminated by HMs with a pollution index trend of As>Zn>Cd>Pb>Hg.In identifying the pollution hotspots,we conclude that the pollution hotspots of Pb,As,Cd,and Hg present a concentrated distribution pattern.Geo-detector method results showed that the dominant driving factors for HMs distribution and accumulation were the potential pollution source and soil permeability.Additionally,the main drivers are variable for different HMs,and the interaction among factors also enhanced soil HMs contamination.Our analysis illustrates how the confounding influences from complex environmental factors can be distilled to identify key factors in pollution formation to guide future remediation strategies.

Early Warning of Heavy Metal Pollution after Tailing Pond Failure Accident

Heavy metal pollution is a major issue after tailing pond failure accident.It is important to predict pollution trends for limited data of pollution sources.A simple phase separation heavy metal model was built for early warning simulation of heavy metal pollution accidents.Based on this,a new simulation framework has been developed to predict the pollution trends of the downstream according to the measured data at upstream sections.By setting the upstream monitoring date as the inflow boundary condition,the changing processes of heavy metal manganese(Mn) with different phases in the downstream can be accurately simulated and forecasted.Results showed that the concentration of the suspended phase in the downstream was larger than that in the aqueous phase and sediment phase.With this,the early warning of pollution trends after accidents could be made a few days ahead.It indicates that the impact of sediment on heavy metal should not be ignored in the early warning of tailing pond failure accidents.

Investigation and Analysis of Soil Pollution of Heavy Metals(Hg,As) in Duanzhou District,Zhaoqing City

The soil heavy metals(Hg and As)in Duanzhou District of Zhaoqing City were determined by AFS200 T atomic fluorescence spectropho-tometer,and the soil environment in Duanzhou District was evaluated by several evaluation methods of soil heavy metal pollution,such as single factor index method,pollution load index method and Nemerow comprehensive pollution index method.Finally,according to the data and conclu-sions,the soil pollution situation in Duanzhou District of Zhaoqing was analyzed.The results will let more people pay attention to the changes of the environment and realize the harm of the environment,and the government can formulate a new plan conducive to the coordinated development of the environment and economy.

13th Five-Year Plan of Anhui Province For Heavy Metal Pollution Prevention and Control Issued

The 13th Five-Year Plan of Anhui Province for Heavy Metal Pollution Prevention and Control('Plan'),jointly prepared by the Anhui Provincial Environmental Protection Department,Anhui Provincial Development and Reform Commission and Anhui Provincial Commission of Economy and Information Technology with technical support from

Characteristics of heavy metals in soil of lead-zinc mining areas and changes of antioxidant enzyme systems in maize leaf under Pb stress

Pb,Cu,Cd,Zn content of soil in mining areas and abandoned land,flats of the Pijiang River and farmlands were inves-tigated.On this basis of soil heavy metal pollution,the changes of antioxidant enzyme system in maize(Qiandan 88)under different Pb concentrations(0,20,40,60,80,100,150,200,500,1000,2000,3000 mg/L)stress were studied.The results show that the content of Pb,Cu,Cd,and Zn in soil is the highest in mining areas and abandoned land,followed by flats of the Pijiang River>farmlands,and that the variation range of Pb,Cu,Cd in mining areas and abandoned land are 106.40-2564.72,14.83-490.88,22.57-712.77 mg/kg,respectively,which are higher than that of the other land use types.When maize is under stress of 20-500 mg/L Pb concentration,T-SOD activity of maize leaves increase with the increase of Pb concentration and the highest value is 50.21 U/mg prot,but under Pb concentration>1000 mg/L stress,T-SOD activity of maize leaves decrease gradually.The activity of POD decreases with the increases of Pb concentra-tion,and the lowest POD activity of leaves in maize with the value of 93.24 U/mg prot is appeared in Pb 1000 mg/L concentration treatment group.MDA content in leaves of maize increases with the increase of the Pb concentration and the highest value is 101.98 nmol/mg prot,then the content of MDA decreases gradually when the Pb concentration is more than 500 mg/L,which indicates that the membrane lipid peroxidation of maize leaves under high concentration of Pb stress is serious and leads to the cell damage.

Source analysis and risk evaluation of heavy metal in the river sediment of polymetallic mining area:Taking the Tonglüshan skarn type Cu-Fe-Au deposit as an example,Hubei section of the Yangtze River Basin,China

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.

The Effect of Bamboo Charcoal Application on Soil Nutrients and Heavy Metals in Rice

Soil heavy metal pollution is becoming more and more serious.Biomass charcoal application can play an important role in alleviating the toxicity of heavy metals in soils.Compared with other biochar,bamboo charcoal has more unique properties and may have a unique effect on heavy metal pollution.Zhejiang Province of Southeastern China is rich in bamboo resources.However,few studies related to bamboo charcoal application for heavy metal remediation in farmland were reported.In this study,four treatments with different amounts of bamboo charcoal application were set up through a field experiment,namely BC0(no bamboo charcoal application),BC1(2500 kg⋅ha^(−1)),BC2(5000 kg⋅ha^(−1)),and BC3(10000 kg⋅ha^(−1)),and each treatment was replicated three times.The results showed that(1)The application of bamboo charcoal significantly increased the soil pH and organic matter content.Compared with BC0,the pH and organic content of BC3 increased by 7.4%and 17.4%(P<0.05)respectively.(2)The HCl-extractable Cd content of paddy soil in the BC1 treatment was significantly lower than other treatments(P<0.05),and decreased by 15.3%,compared with BC0.The soil HCl-extractable Zn and Cu content did not differ significantly between treatments(P>0.05).(3)With the increase of bamboo charcoal application,the Cd content in rice gradually decreased,the BC3 treatment significantly decreased by 39.0%(P<0.05),and the Zn and Cu contents in rice did not differ significantly between treatments(P>0.05),compared with BC0.(4)Soil pH,organic matter and Cd in rice seeds were significantly negatively correlated(P<0.01).The heavy metal content in rice does not change with the change of heavy metal content with HCl-extractable state in soil.It means bamboo charcoal does not reduce heavy metal content in rice by simply declining the heavy metal content with HCl-extractable state.The mechanism of action is relatively complicated,and further study is needed.

Heavy Metal Risk Assessment of Soils and Crops in the Intensive Mining Area of Gejiu, Yunnan Province

In order to investigate the heavy metal contamination of soil-crop in mining-intensive areas of Gejiu stannary in Yunnan Province and its risk to human health, the single-factor contamination index method and the Nemero comprehensive contamination index method were used to evaluate the contamination risk of heavy metals (Cd and As) in the soil of mining-intensive areas, and the health risk evaluation model was used to study the risk brought by residents through the consumption of maize, wheat and broad beans. The results showed that the mean values of total As and Cd in the soil of the study area were 146 and 2.32 mg·kg-1, which were 8 and 10.5 times higher than the background values of soil environment in Yunnan Province and belonged to heavy pollution;the enrichment coefficients of As and Cd in maize were 0.1% and 5.7%, in wheat were 0.3% and 11.5%, in fava beans were 0.1% and 4.9%;the soil contamination indices in the four study areas of A, B, C, and D were 7.275, 6.797, 5.618, and 5.060, respectively. The results indicated that the soils in the study areas belonged to heavy contamination levels, and the enrichment ability of Cd in all three crops was stronger than that of As, with wheat being the strongest, As in the three crops and Cd in broad beans might be harmful to children. As in wheat and broad beans may be harmful to adults.

Tissue distribution of cadmium and its effect on reproduction in Spodoptera exigua

Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua exposed to cadmium and its effects on the growth and development of the parents and the offspring were investigated.Under the stress of different concentrations of cadmium(0.2,3.2,and 51.2 mg kg^(-1)),the cadmium content in each tissue of S.exigua increased in a dose-dependent manner.At the larval stage,the highest cadmium accumulation was found in midgut in all three cadmium treatments,but at the adult stage,the highest cadmium content was found in fat body.In addition,the cadmium content in ovaries was much higher than in testes.When F1S.exigua was stressed by cadmium and the F_(2)generation was not fed a cadmium-containing diet,the larval survival,pupation rate,emergence rate and fecundity of the F_(2)generation were significantly reduced in the 51.2 mg kg^(-1)treatment compared to the corresponding F1generation.Even in the F_(2)generation of the 3.2 mg kg^(-1)treatment,the fecundity was significantly lower than in the parental generation.The fecundity of the only-female stressed treatment was significantly lower than that of the only-male stressed treatment at the 3.2 and 51.2 mg kg^(-1)cadmium exposure levels.When only mothers were stressed at the larval stage,the fecundity of the F_(2)generation was significantly lower than that of the F1generation in the 51.2 mg kg^(-1)treatment,and it was also significantly lower than in the 3.2 and 0.2 mg kg^(-1)treatments.The results of our study can provide useful information for forecasting the population increase trends under different heavy metal stress conditions and for the reliable environmental risk assessment of heavy metal pollution.

Recovery time of macroinvertebrate community from Cd pollution in Longjiang River,Guangxi,China

Estimating recovery times from pollution incident is an important issue of targeted biomonitoring programs.In the present study,the impact and recovery of macroinvertebrate communities from a cadmium wastewater discharge in the Longjiang River,Guangxi,China,in early January 2012 were studied based on 83 samples collected in fi ve surveys within 20 months after the incident.The pollution aff ected seriously the local aquatic biota,and consequently,the invertebrate abundance and species richness were reduced considerably.Twelve months later,the taxonomic number of macroinvertebrates began to increase.However,sensitive taxa remained rare.Twenty months later,the taxon richness and abundance of macroinvertebrates increased signifi cantly compared to those in the previous four time points.To explore the possible time-scale over which pre-disturbance conditions might occur,we chose four diff erent typical metrics of taxa richness(total taxa number,cumulative taxa number,taxa number per samples,and the Shannon-Wiener diversity index)and extrapolated modeled recovery trajectories.Target values for the four metrics were set at average values for sites from the nearby Lijiang River,which were used as a reference.Assuming a continued linear trajectory,the recovery times were estimated to be 52,39,39,and 31 months,respectively,which was roughly 3-5 years.This is consistent with results from recovery times from other studies of acute pollution cases,but contrasted strongly to the much longer recovery times associated with chronic pollution from groundwater contamination and mine-tailing runoff.

铜冶炼过程中的砷反应行为及其处理技术的回顾

砷作为五大有毒元素之一,其对生物体和生态环境的健康威胁已引起公众的广泛关注。有色金属冶炼,特别是铜冶炼,是砷的重要人为来源,应被列为重点关注对象。因此,明确砷在铜冶炼过程中的行为,对铜冶炼企业的正常生产和环境保护具有重要意义。本工作简要介绍了冶炼用工业铜矿物和铜矿中砷的赋存形式,以及铜冶炼工艺的演变。此外,还分析了砷在有代表性的铜冶炼过程中的挥发、转化和分布行为,明确了其流向和富集规律。研究了其他矿物成分(Cu、Pb、Zn、Fe、Ca、Si)与砷在冶炼副产品(铜渣和烟尘)形成过程中的相互作用,阐明了砷污染物的形成机制。最后,分析了冶炼烟气、烟尘和铜渣中砷的控制技术,提出了未来通过将砷污染物转化为金属砷来回收砷的可能策略。

The Application of Fertilizer and AMF Promotes Growth and Reduces the Cadmium and Lead Contents of Ryegrass (Lolium multiflorum L.) in a Copper Mining Area

Heavy metal-polluted soil was collected from the Pulang copper mine in Shangri-La City,Yunnan Province,Southwest China.The effects of fertilizer(organic and inorganic)and arbuscular mycorrhizal fungi(AMF)on ryegrass(Lolium multiflorum L.)growth,root morphology,mineral nutrition and cadmium(Cd)and lead(Pb)contents were investigated by pot experiments.The results showed that both fertilizer and AMF significantly ameliorated the root morphology and mineral nutrition,reduced the Cd and Pb contents,and promoted the growth of ryegrass.Among all treatments,the combined application of organic–inorganic compound fertilizer with AMF had the highest effect,resulting in increases in root length,surface area and branch number by 2.3,1.1,and 3.9 times,respectively;an 88%increase in plant biomass;a nitrogen content increase of 2.3 and 1.2 times,and phosphorus content increase of 62%and 68%in shoots and roots,respectively was also recorded as well as decreases in Cd content by 34%and 62%and Pb content by 47%and 34%in shoots and roots,respectively.Twofactor analysis showed that both fertilizer and AMF significantly promoted ryegrass growth(plant height,biomass,chlorophyll content,root length,nitrogen and phosphorus content)and reduced the Cd and Pb contents in roots,and there was a synergistic effect between them.Moreover,the nitrogen and phosphorus contents were very significantly positively correlated with the shoot and root biomasses but very significantly negatively correlated with the Cd and Pb contents of ryegrass.Thus,the application of fertilizer and AMF synergistically improved ryegrass growth on polluted soils in the copper mining area.

The Application of Regional Coordinate in the Relatively Heavily Polluted Area of Chromium in Water of the Hun River, Northeast China

The aim of the present investigation was to research the relatively heavily polluted area of chromium in water of the Hun River. According to variance analysis, the concentrations of chromium in water showed significant differences at different sampling stations. In addition, we obtained the static concentration function of chromium in water by using a curve-fitting tool and the measured data. It was clear that the static concentration function perfectly revealed the change in regulations between the concentration of chromium in water and spatial coordinates. We furthermore determined the relatively heavily polluted area of chromium in water by using a regional coordinate formula. The results indicated that the relatively heavily polluted area of chromium in water was from H1 to H2, which was highly consistent with the measured data. It is clear that the determination of the relatively heavily polluted area of chromium is helpful to the comprehensive treatment of chromium pollution. The static concentration function and the regional coordinate of the relatively heavily polluted area of chromium in water comprehensively describe the distribution characteristics of chromium in water, which provide a scientific basis for water environment improvement and risk management in the Hun River.

Heavy metal accumulation characteristics and physiological response of Sabina chinensis and Platycladus orientalis to atmospheric pollution

Heavy metal(Cu,Mn,Zn,Pb,and Cd)concentrations were measured in the leaves of Sabina chinensis and Platycladus orientalis collected from urban,suburban,and rural sites in Tianjin,China.Photosynthetic pigment contents,reactive oxygen species content,malondialdehyde(MDA)content and antioxidant enzyme activity were investigated,providing physiological response parameters.Our comparison of the sites revealed that urbanization significantly influenced the heavy metal concentrations in both plant leaves.At the rural site,both plant leaves exhibited the lowest heavy metal accumulation.The highest Cu,Mn,and Zn concentrations were found in S.chinensis leaves from the urban site;the highest Pb and Cd concentrations were found in P.orientalis leaves from the urban site.These results indicate that the urban site contained larger heavy metal concentrations in the plant leaves that may reflect the anthropogenic emission gradient.It is also found that S.chinensis may be used to monitor airborne heavy metal pollution because it is highly quick response to heavy metals,while P.orientalis may be used for mitigation due to its high resistance.The results of this study can contribute to the development of monitoring and environmental management plans by providing information on sensitive and resistant tree species for city greening in North China.

Synergistic effects of phosphoric acid modified hydrochar and coal gangue-based zeolite on bioavailability and accumulation of cadmium and lead in contaminated soil

In this paper,a novel compound was developed by mixing H_(3)PO_(4)-modified cauliflower leaves hydrochar(CLH)and coal gangue-based Na-X zeolite(ZL).An alkaline soil contaminated with cadmium(Cd)and lead(Pb)was amended through the individual and synergistic application of CLH and ZL(1%CLH,2%CLH,1%ZL,2%ZL and 1%CLH+1%ZL),and Chinese cabbage was grown on it.Individual application of CLH was superior to ZL on decreasing the pH of alkaline soil and increasing soil available phosphorus(Olsen-P)and soil organic matter(SOM).In contrast,their combined application significantly improved the soil cation exchange capacity(CEC).Besides,the 1%CLH+1%ZL was the most efficient treatment in decreasing diethylenetriamine pentaacetate(DTPA)-extractable Cd/Pb and concentrations of these two metals in cabbage root and shoot.Their synergistic application could better increase Cd and Pb immobilization and cabbage yield than their alone application.Furthermore,the immobilization of Pb for all treatments was higher than that of Cd.The synergistic immobilization mechanism of CLH and ZL reflected that the CLH precipitated and complexed with these two metals,which may block the pores of hydrochar or wrap on the surface of hydrochar.So the continuous adsorption and complexation were prevented.Nevertheless,ZL could probably alleviate this obstacle.This finding provides helpful information about using CLH combined with ZL as a soil stabilizer to immobilize heavy metals in contaminated alkaline soil.

Study on heavy metal concentrations in river sediments through the total amount evaluation method

A quantitative method to evaluate the amounts of heavy metals in river sediments is established. Using the BT Drainage River in North China as a study object, six representative cross sections were selected for measurement of heavy metal indicators in sediments, and then the main contamination indicators were determined by performing a potential ecological risk assessment. Using a section of this river as an example, the total amounts of the main pollution indicators and those of their harmful forms are estimated by the Surfer software, which simulates the pollution status within the downstream sediments of the outfall at this section. The calculation results could provide a theoretical guideline and data support for pollution treatment of the BT Drainage River.