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1.
Direct ultraviolet (UV) photolysis coupled with modification of solution pH was explored as a method for the removal of organic micropollutants from groundwater. Photodegradation rates of most of the investigated compounds were pH dependent, however, its correlation with photodegradation rate varied among compounds. The potential of the pH modification during photolysis was determined for removal of a mixture of two pharmaceuticals sulfamethoxazole (SMX) and triclosan (TCS) in groundwater. The treatment included initial photolysis of the mixture at the optimal pH for TCS (i.e., 7.5–7.9), followed by pH modification to the optimal pH for SMX (i.e., 5), prior to a second irradiation period. The described procedure dramatically increased the removal efficiency (up to threefold) of the treated mixture compared to UV treatment at constant pH.  相似文献   

2.
To provide good quality of drinking water, a biological system to remove ammonium-nitrogen (NH4-N) from groundwater was studied in this research. The NH4-N removal system consists of two attached growth reactors: one for nitrification and the other for hydrogenotrophic denitrification (H. denitrification). The nitrification reactor, fed by the NH4-N contained water, could remove NH4-N without any need of aeration. The nitrification efficiency was increased by reactor length; the highest efficiency of 92?% was achieved at the longest reactor of 100?cm. A high Fe in groundwater affected the reactor performance by decreasing the efficiency, while a low inorganic carbon (IC) had no effects. Despite of good efficiency in terms of NH4-N removal, the nitrification reactor increased the concentration of NO3-N in its effluent. To treat the NO3-N, a H. denitrification reactor was set up after the nitrification reactor. Efficiency of the H. denitrification reactor was enhanced by increasing H2 flow rates. The efficiencies were 3, 27, and 90?% for 30, 50, and 70?mL/min of H2 flow rates, respectively. It was also found that the NO3-N contained water (water from the nitrification reactor) had to supply IC (i.e., NaHCO3 or CO2) for efficient H. denitrification; however, an on-site reactor showed that it can be achieved even without IC addition. The treated water contained low NH4-N and NO3-N of <1.5 and <11.3?mg/L, respectively, which comply with drinking water standards. The good performance of the reactors in terms of high efficiency, no aeration need, and low H2 supply indicated appropriateness of the system for groundwater treatment.  相似文献   

3.
This work examined the removal of heavy metals in a system consisting of ultrafiltration (UF) or microfiltration (MF) membranes combined with sludge and minerals. The metals under examination were Ni(II), Cu(II), Pb(II), and Zn(II), while the system performance was investigated with respect to several operating parameters. Metal removal was achieved through various processes including chemical precipitation, biosorption, adsorption, ion exchange, and finally retention of the metals by the membranes. The pH had a profound effect on metal removal, as the alkaline environment favored the metal removal process. The use of sludge resulted in increased levels of metal uptake which was further enhanced with the addition of minerals. The metal removal mechanisms depended on the pH, the metal, and mineral type. The combined sludge?Cmineral?CUF system could effectively remove metal ions at an alkaline environment (pH?=?8), meeting the US EPA recommended long-term reuse limits of lead and copper and the short-term reuse limits of nickel and zinc for irrigation purposes, provided that specific mineral dosages were added.  相似文献   

4.
Storm water detention devices collect runoff from impermeable catchments. They provide flow attenuation as well as storage capacity, and rely on natural self-purification processes such as sedimentation, filtration and microbial degradation. The aim was to assess the performance of an experimental combined planted gravel filter, storm water detention and infiltration tank system treating runoff from a car park and its access road. Flows were modeled with the US EPA Storm Water Management Model. An overall water balance of the system was compiled, demonstrating that 50% of the rainfall volume escaped the system as evaporation, whereas, of the remaining 50%, approximately two thirds were infiltrated and one third was discharged into the sewer system. These findings illustrated the importance of evaporation in source control, and showed that infiltration can be applied successfully even on man-made urban soils with low permeability. The assessment of the system’s hydrological efficiency indicated mean lag times of 1.84 and 10.6 h for the gravel filter and the entire system, respectively. Mean flow volume reductions of 70% and mean peak flow reductions of 90% were achieved compared to conventional drainage. The assessment of the pollutant removal efficiency resulted in promising removal efficiencies for biochemical oxygen demand (77%), suspended solids (83%), nitrate-nitrogen (32%) and ortho-phosphate-phosphorus (47%). The most important removal processes were identified as biological degradation (predominantly within the gravel ditch), sedimentation and infiltration.  相似文献   

5.
实验模拟地下水修复,以被垃圾渗滤液污染地下水为研究对象,分别用沸石、无烟煤、陶粒、活性炭、炉渣、钢渣、粉煤灰、零价铁作为填充材料,设计6种可渗透反应墙（PRB）,分别为反应器1、2、3、4、5和6。分3个试验阶段对PRB技术修复污染地下水中NH4+ 变化规律进行实验模拟研究,分析了反应器NH4+ 变化原因并探讨了NH4+ 变化机理。实验结果表明：NH4+ 去除率普遍较低,含沸石反应器脱氮效果最好,也仅为49.8%,部分反应器甚至出现负值;水解酸化作用,产生一定量NH4+ 和有机酸,造成反应器出水pH值降低和填充材料NH4+ 相对去除率偏低。PRB技术治理渗滤液污染地下水具有一定可行性,但技术有待继续深入研究。  相似文献   

6.
A unique test chamber system, which enables experiments with plants under highly controlled environmental conditions, was used to examine the pollutant removal efficiency of plants. For this purpose, the removal of two different volatile organic compounds (VOC) (toluene, 2-ethylhexanol) from the air by aerial plant parts of two common indoor plant species (Dieffenbachia maculata and Spathiphyllum wallisii) was monitored. While the control over environmental conditions (temperature, relative humidity, CO2 content, and light condition) worked very well in all experiments, control experiments with the empty chamber revealed high losses of VOC, especially 2-ethylhexanol, over the test duration of 48 h. Nonetheless, compared to the empty chamber, a significantly stronger and more rapid decline in the toluene as well as in the 2-ethylhexanol concentrations was observed when plants were present in the chamber. Interestingly, almost the same VOC removal as by aerial plant parts could be achieved by potting soil without plants. A comparative literature survey revealed substantial heterogeneity in previous results concerning the VOC removal efficiency of plants. This can be mainly attributed to a high diversity in experimental setup. The experimental setup used in the current study offers an excellent opportunity to examine also plant physiological responses to pollutant exposure (or other stressors) under highly controlled conditions. For the analysis of VOC removal under typical indoor conditions, to obtain data for the assessment of realistic VOC removal efficiencies by plants in rooms and offices, a guideline would be helpful to achieve more coherent findings in this field of research.  相似文献   

7.
The selectivity and uptake capacity of horticultural peat available in Romania was evaluated with respect to the removal of Cd(II), Cr(VI) and Pb(II) ions from aqueous solution. The kinetics, sorption capacities, selectivity and pH dependence of sorption were determined. The influence of metal concentration in solution is discussed in the terms of Langmuir and Freundlich isotherm and constants. Sorption capacities increased with increasing metal concentration in solution. For solutions containing 300 mg/l of metal, the observed uptake capacities were 20 mg Cd(II)/g peat, 15 mg Cr(VI)/g peat and 30 mg Pb(II)/g peat. The study proved that horticultural peat is a suitable material for the removal of the studied heavy metal ions from aqueous solutions, achieving removal efficiencies higher than 90%, and could be considered as a potential material for treating effluent polluted with Cd(II), Cr(VI) and Pb(II) ions.  相似文献   

8.
Nie  Xinxing  Zhang  Zhiyi  Xia  Xiange  Yang  Li  Fan  Xianpeng  Zheng  Manjie 《Journal of Soils and Sediments》2020,20(4):2043-2052
Purpose

Magnetic removal techniques using functionalized magnetic nanoparticles as adsorbents have been frequently tested for use in the removal of heavy metals in aqueous solution, but seldom in farmland soil. Here, a novel magnetic microparticle solid chelator (MSC) was employed as the adsorbent for magnetic removal and/or immobilization of Cd and Zn in a paddy soil (PS), an upland soil (US), and a paddy–upland rotation soil (RS) with different degrees of pollution.

Materials and methods

MSC was applied to 14 kg air-dried soil samples (PS, US, and RS) at the dosage of 1% (w/w), and then watered, and intermittently stirred. Finally, the MSC–metal complexes were retrieved using a magnetic device (MCR treatment) or not (MC treatment), and the removal efficiency of soil Cd and Zn in MCR treatment was evaluated. After magnetic separation of MSC–metal complexes, pot experiments were performed to investigate the impacts of the magnetic remediation process on rice growth, the phytoavailability of soil Cd and Zn, and the accumulation of Cd and Zn in rice plants.

Results and discussion

The MCR treatment exhibited recovery rates of 55.4%, 49.6%, and 19.0% for MSC–metal complexes in PS, US, and RS, respectively, which brought about removal efficiencies of 2.2–12.2% for Cd and 1.9–4.6% for Zn. The MC and MCR treatments substantially decreased the availability of soil Cd, but not soil Zn; this effect was more remarkable when using CaCl2 instead of DTPA as the extractant for determination of bioavailable metals. Furthermore, the CaCl2-extractable Cd and Zn had a more significant relationship with Cd and Zn concentrations in rice roots. The MC and MCR treatments led to dramatic reductions in rice grain Cd of 23.9–72.1% and 37.3–63.9%, respectively, in the three soils relative to the respective controls. The MC and MCR treatments also exhibited an inhibitory effects on rice grain Zn accumulation in US (10.6% and 4.3% decreases, respectively) and RS (9.3% and 19.5% decreases, respectively), but not in PS. Moreover, the grain yield was unaffected under the MCR treatment in the three soils, and significantly increased by 29.8% under the MC treatment in US.

Conclusions

Our study suggests that MSC-based magnetic remediation technique can effectively immobilize and/or remove Cd and Zn in farmland soils, decreasing their uptake by rice plants, with no adverse effects on grain yield.

  相似文献   

9.
Copper biosorption onto chemically modified biomass of marine alga Sargassum filipendula was investigated in a batch reactor and a fixed bed column. Experiments were carried out in the batch reactor to obtain kinetic and equilibrium data and to assess the copper desorption efficiency of different eluent solutions. The pseudo-first-order, pseudo-second-order, and Langmuir kinetic models were used to correlate kinetic data. The experimental data fitted well to the pseudo first order and Langmuir kinetic models. Langmuir and Freundlich models were applied to describe the equilibrium data obtained at a fixed temperature of 30°C and at pH values of 3.0, 4.0, 5.0, and 6.0. The maximum capacities of copper biosorption onto the algal biomass were 1.43, 1.59, 2.40, and 2.36 mequiv./g at pH 3.0, 4.0, 5.0, and 6.0, respectively. The efficiencies of two eluent solutions (calcium chloride and hydrochloric acid) for copper removal from the biomass were evaluated at different concentrations (0.1, 0.2, 0.5, and 1.0 mol/L). The efficiencies of the calcium chloride solutions varied from 1% to 14%, while efficiencies varying from 95% to 99% were obtained when hydrochloric acid solutions were applied. Three adsorption/desorption cycles were carried out in a fixed bed column using 0.1 mol/L hydrochloric acid as eluent solution. The results showed that an increase in the number of cycles led to a reduction in the adsorption capacity of the alga. The desorbed copper fraction presented no significant variation, remaining around 63% in the three adsorption/desorption cycles.  相似文献   

10.
Recently, it has been found that fish oils contain a high proportion of contaminants, namely, polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (cPCBs). In this study, the removal of contaminants from fish oil by supercritical CO2 extraction (SCE) and by using adsorbents (0.13 wt % of oil) was investigated. Dioxins and cPCBs were extracted from fish oil by SCE at a temperature of 60 degrees C and a pressure of 28 MPa, and the removal efficiencies for PCDDs and PCDFs were in the range of 15-90% and those for cPCBs were in the range of 70-90%. However, 40% of the oil was extracted simultaneously with contaminants. On the adsorbent treatment, activated carbon showed high efficiency, and the removal efficiencies were >90% for PCDDs and PCDFs, but below 30% for cPCBs. A combination of both of these methods is more effective, and almost 100% of the total toxicity equivalence quantity value could be reduced.  相似文献   

11.
Xiong  Ya  He  Chun  An  Taicheng  Zhu  Xihai  Karlsson  Hans T. 《Water, air, and soil pollution》2003,144(1-4):67-79
A new electrochemical reactor, three-phase three-dimensional electrode reactor, was designed and used to investigate theremoval of formic acid from simulated wastewater. The experimental results were assessed in term of Chemical OxygenDemand (COD) removal efficiency. The results showed that the three-phase three-dimensional electrodes could effectively removeformic acid. Its COD removal efficiency was much higher than those of two-dimensional electrodes and common three-dimensionalelectrodes, respectively. The COD removal efficiency of the three-phase three-dimensional electrodes using air as a spargegas increased 13.5% relative to that using nitrogen as a spargegas. The observation indicated that the sparged air in the three-phase three-dimensional electrodes not only participated insome physical processes but also played an important role in electrochemical reactions to assist COD removal.  相似文献   

12.
Pollutant removal was compared among subsurface flow constructed wetland (CW) mesocosms used for dairy farm wastewater treatment. Supplemental aeration, flow direction, and the use of phosphorus-reducing filters (PRFs) were varied among the CWs. The following were compared: (1) vertical flow CWs with and without supplemental aeration, (2) aerated CWs with horizontal and vertical flow directions, (3) single-cell and two-cell treatment systems, and (4) wetland-wetland systems (two CWs in series) and wetland-PRF systems (a CW followed by a PRF). The results from this investigation showed that, first, nearly all treatment strategies, either singly or in pairs, substantially reduced almost all the contaminants we tested. Second, supplemental aeration resulted in higher ammonium-nitrogen (NH4-N) removal efficiencies in aerated vertical flow CWs, compared to unaerated CWs. However, it caused no further improvement in dissolved reactive phosphorus (DRP), total suspended solids (TSS), E. coli, or BOD5 removal. Third, there was no difference between aerated horizontal and aerated vertical flow CWs in removal of any of the tested contaminants. Fourth, adding a second stage of treatment significantly improved DRP, TSS, E. coli, and NH4-N removal, but not BOD5. Finally, treatment systems with PRFs showed superior performance in DRP and E. coli removal.  相似文献   

13.
The performances of a new and a mature integrated constructed wetland (ICW) system treating domestic wastewater were evaluated for the first time. The new ICW in Glaslough (near Monaghan, Ireland) comprises five wetland cells, and the mature system in Dunhill (near Waterford, Ireland) comprises four cells. The performance assessment for these systems is based on physical and chemical parameters collected for 1 year in Glaslough and 5 years in Dunhill. The removal efficiencies for the former system were relatively good if compared to the international literature: biochemical oxygen demand (BOD, 99.4%), chemical oxygen demand (COD, 97.0%), suspended solids (SS, 99.5%), ammonia nitrogen (99.0%), nitrate nitrogen (93.5%), and molybdate-reactive phosphorus (MRP, 99.2%). However, the mature ICW had removal efficiencies that decreased over time as the Dunhill village expanded rapidly. The mean removal efficiencies were as follows: BOD (95.2%), COD (89.1%), SS (97.2%), ammonia nitrogen (58.2%), nitrate nitrogen (?11.8%), and MRP (34.0%). The findings indicate that ICW are efficient in removing BOD, COD, SS, and ammonia nitrogen from domestic wastewater. Moreover, both ICW systems did not pollute the receiving surface waters and the groundwater.  相似文献   

14.
Leachates, particularly those from mature landfills, are difficult to treat by biological processes because of their high toxicity and low biodegradability. Therefore, the development of new treatment technology is necessary. The treatment of landfill leachate by peroxicoagulation and solar peroxicoagulation using a batch electrolytic reactor with a Fe cathode and a Cu anode is proposed. The tested operational variables included pH (2.8 and 8.2), current density (11 and 16 mA cm?2), treatment time (5, 10, 15, 20, 25, and 30 min), and presence of solar ultraviolet (UV) light and were collected using a compound parabolic collector. The optimum conditions were a pH, current density, and treatment time of 2.8, 16 mA cm?2, and 10 min, respectively. The presence of UV did not have a significant effect. The chemical oxygen demand and biochemical oxygen demand removed were 62.3% and 55.5%, respectively. The results of UV-visible absorption, fluorescence, and Fourier transform infrared spectroscopy measurements confirm the oxidation process.  相似文献   

15.

Purpose

Soil washing with chelators is a viable treatment alternative for remediating multi-contaminated soils. The aim of this study was to investigate the removal efficiencies of Cd, Zn, Pb, and Cu in alkaline and acid multi-metal-contaminated soils by washing with the mixed chelators (MC).

Materials and methods

The batch experiments were carried out to evaluate the removal efficiencies of heavy metals in contaminated soils by the MC with different molar ratios of EDTA, GLDA, and citric acid, and evaluated the washing factors, including contact time, pH, MC concentration, and single and multiple washings at the same MC dose, on the removal efficiencies.

Results and discussion

Results showed that the removal efficiencies for Cd, Zn, Pb, and Cu by the MC (the molar ratio of EDTA, GLDA, and citric acid was 1:1:3) were as much as those of the only EDTA washing from both soil at the same application dose of total chelators; moreover, the application dose of EDTA decreased by 80%. For the alkaline-contaminated soil, the removal efficiencies of Cd, Zn, Pb, and Cu decreased with the increasing of the solution pH, which was opposite to acid-contaminated soil. This was attributed to that the metal-ligand complex could be obviously re-adsorbed on the soil surface sites, particularly in low pH values. The removal efficiencies of Cd, Zn, Pb, and Cu depended on MC concentration. A higher MC concentration led to a more effective removal of Cd, Zn, Pb, and Cu in alkaline-contaminated soil; however, their changes were slightly increased in acid-contaminated soil. At the same dose of MC, single washing with higher MC concentration might be favorable to remove heavy metals, moreover, with much less wastewater generation.

Conclusions

The MC (the molar ratio of EDTA, GLDA, and citric acid was 1:1:3) may be a useful, environmentally friendly, and cost-effective chelators to remediate heavily multi-metal-contaminated soil.
  相似文献   

16.
The sorption of Pb(II), Cr(III) and Cr(VI) from aqueous solution using alum-derived water treatment sludge was investigated using the batch adsorption technique. Samples of sludge from two separate water treatment plants were used (one where alum was used alone and one where it was used in combination with activated C). The sorption characteristics of the two samples were generally very similar. Sorption isotherm data for all three ions fitted equally well to both Freundlich and Langmuir equations. Maximum sorption capacity and indices of sorption intensity both followed the order: Cr(III)?>?Pb(II)?>?Cr(VI). Kinetic data correlated well with a pseudo-second-order kinetic model suggesting the process involved was chemisorption. Sorption was pH-dependant with percentage sorption of Cr(III) and Pb(II) increasing from <30% to 100% between pH?3 and 6 whilst that of Cr(VI) declined greatly between pH?5 and 8. HNO3 at a concentration of 0.1?M was effective at removing sorbed Cr(III) and Pb(II) from the sludge surfaces and regeneration was successful for eight sorption/removal cycles. It was concluded that water treatment sludge is a suitable material from which to develop a low-cost adsorbent for removal of Cr and Pb from wastewater streams.  相似文献   

17.
Indoor air-borne loads of volatile organic compounds (VOCs) are usually significantly higher than those outdoors, and chronic exposures can cause health problems. Our previous laboratory studies have shown that the potted-plant microcosm, induced by an initial dose, can eliminate high air-borne VOC concentrations, the primary removal agents being potting-mix microorganisms, selected and maintained in the plant/root-zone microcosm. Our office field-study, reported in the preceding paper, showed that, when total VOC (TVOC) loads in reference offices (0 plants) rose above about 100 ppb, levels were generally reduced by up to 75% (to < 100 ppb) in offices with any one of three planting regimes. The results indicate the induction of the VOC removal mechanism at TVOC levels above a threshold of about 100 ppb. The aims of this laboratory dose-response study were to explore and analyse this response. Over from 5 to 9 days, doses of 0.2, 1.0, 10 and 100 ppm toluene and m-xylene were applied and replenished, singly and as mixtures, to potted-plants of the same two species used in the office study. The results confirmed the induction of the VOC removal response at the lowest test dosage, i.e in the middle of the TVOC range found in the offices, and showed that, with subsequent dosage increments, further stepwise induction occurred, with rate increases of several orders of magnitude. At each dosage, with induction, VOC concentrations could be reduced to below GC detection limits (< 20 ppb) within 24 h. A synergistic interaction was found with the binary mixtures, toluene accelerating m-xylene removal, at least at lower dosages. The results of these two studies together demonstrate that the potted-plant microcosm can provide an effective, self-regulating, sustainable bioremediation or phytoremediation system for VOC pollution in indoor air.  相似文献   

18.
Pharmaceuticals and personal care products (PPCPs) can reach soil and aquatic environments through land application of wastewater effluent and agricultural runoff. The objective of this research was to assess the fate of PPCPs at field scale. PPCPs were measured systematically in a wastewater treatment plant (WWTP), and in soil and groundwater receiving treated effluent from the WWTP. A land application site in West Texas was used as the study site; it has received treated wastewater effluent from the WWTP for more than 70 years in order to remove additional nutrients and irrigate non-edible crops. Target compounds (estrone, 17??-estradiol, estriol, 17??-ethynylestradiol, triclosan, caffeine, ibuprofen, and ciprofloxacin) in wastewater, sewage sludge, soil, and groundwater were determined using HPLC/UV with qualitative confirmatory analyses using GC/MS. Samples were collected quarterly over 12 months for wastewater and sludge samples and over 9 months for soil and groundwater samples. Results indicated that concentrations of PPCPs in wastewater influent, effluent, sludge solid phase, and sludge liquid phase were in the range of non-detected (ND)-183 ??g/L, ND-83 ??g/L, ND-19 ??g/g, and ND-50 ??g/L, respectively. Concentrations in soil and groundwater samples were in the range of ND-319 ng/g and ND-1,745 ??g/L, respectively. GC/MS confirmation data were consistent with the results of HPLC/UV analyses. Overall, data indicate that PPCPs in the wastewater effluent from the WWTP transport both vertically and horizontally in the soil, and eventually reach groundwater following land application of the effluent.  相似文献   

19.
利用植物浮床系统,通过室内静态模拟试验,研究了pH和曝气对水生植物净化富营养化水体影响。试验结果表明,不同pH处理6 d后,植物系统在pH8.9下对TN,CODMn,BOD5的去除效果最好,TP的去除效果在pH6.7下最好,Chla的去除效果在pH5.0下最好。然而,无植物系统中,TN,TP的去除效果在pH8.9下最好,BOD5的去除效果在pH6.7下最好,CODMn,Chla的去除效果在pH5.0下最好。有无植物系统中,曝气处理6 d后对TN影响很大,但去除率明显小于不曝气处理(P<0.001),除在豆瓣菜系统中,曝气还对CODMn去除产生一定的影响,但对TP和Chla的去除无影响。本试验结果还表明,植物修复系统和无植物系统中,不同pH处理下,水体中NH4-N,NO3-N,NO2-N的去除效果均在pH8.9处理下最好,且在pH8.9 曝气联合作用下水体中NH4-N,NO3-N,NO2-N的去除率也最高。  相似文献   

20.

Purpose

Small arm shooting ranges located in peatland areas are gathering increased attention due to severe metal and antimony (Sb) contamination and challenging conditions for remediation. The goal of the present study was to gain further understanding of the distribution, binding and transport of lead (Pb), copper (Cu) and Sb in peatland contaminated by small arm shooting range activities.

Materials and methods

A field experiment was carried out at a recently closed shooting range facility in Norway, including (i) peat soil sampling for various selective extractions (water, chemical extractions, extractions by diffusive gradients in thin films, DGT), (ii) establishing groundwater wells for groundwater sampling and monitoring of groundwater level and (iii) sampling of water and sediments in surface water. The results from groundwater monitoring were used to carry out hydrogeological numerical simulations using Seep/W and CTran/W. These models were used to evaluate the residence time of the contaminants in the peatland.

Results and discussion

Increased metal concentrations were observed in the top layer of the peatland, indicating low vertical transport. Groundwater revealed high concentrations of Pb (22 ± 5 μg/L), Cu (16 ± 6 μg/L) and Sb (11 ± 2 μg/L), the dominating contaminant source to the downstream surface water. Hydrogeological modelling indicated that transport mainly happened in the upper peat layer, as a result of a higher hydraulic conductivity close to the surface and a high groundwater table. Pb (6.9 ± 0.1 μg/L), Cu (24.0 ± 0.0 μg/L) and Sb (7.4 ± 0.1 μg/L) concentrations in the stream samples confirmed the spreading of contaminants at levels toxic to aquatic organisms. Pb and Cu were most likely associated with dissolved organic carbon (DOC), whereas Sb showed no correlation with DOC.

Conclusions

The elements contaminating the peatland may leak to the nearby water course over a long-term period. Copper showed the highest concentration in the stream water despite considerably higher levels of Pb in the peat soil. Strong complexation of Cu to dissolved organic matter might explain this observation. Only a little fraction of the contaminants is transported in a particulate form, and therefore are increased sedimentation measures not considered as viable remediation option.
  相似文献   

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