| 1. |
- Alling, Vanja, et al.
(författare)
-
The role of biochar in retaining nutrients in amended tropical soils
- 2014
-
Ingår i: Journal of Plant Nutrition And Soil Science/Zeitschrift für Pflanzenernahrung und Bodenkunde. - : Wiley. - 1436-8730 .- 1522-2624. ; 177:5, s. 671-680
-
Tidskriftsartikel (refereegranskat)abstract
- This study investigated the effect of biochar amendments on the retention and availability of plant nutrients and Al in seven acidic tropical soils from Zambia and Indonesia. The experiments carried out investigated whether the adsorption capacity of NH4+ in the soils increased upon the addition of biochar and which effect biochar had on available concentrations of NO3-, K+, Mn2+, Mg2+, PO43-, and Al3+. These nutrients were selected as they represent those important to plant growth and soil quality. No significant increases or decreases in aqueous NH4+-N concentration with additions of biochar were detected. The Gaines-Thomas model was used in order to calculate selectivity coefficients for NH4+ exchange (K-gt values). Following the addition of biochar to soil, K-gt values decreased showing a reduction in the selective binding of NH4+ in the biochar amended soil compared to the control. The concentration of NO3- increased following the addition of biochar to the soils. The addition of 5 and 10% biochar to the Indonesian soil did not significantly alter (t-test confidence level 0.05) the sorption of PO43- to the soil-biochar mixtures as compared to the soil alone. However, the addition of biochar to the soil from Zambia increased the sorption of PO43- compared to the soil alone. The concentrations of K+ and Mg2+ were significantly increased for almost all soils (t-test at the 0.05 confidence level) following the addition of biochar. Addition of biochar to all but two soils significantly decreased (t-test confidence level 0.05) Mn2+ concentrations. The concentration of Al3+ in the soils decreased exponentially significantly (t-test confidence level 0.05) following the amendment of biochar in accordance with the increase in pH observed when biochar was added to the soil. These results show that biochar has the ability to release essential plant growth nutrients as well as alleviate Al toxicity in these soils.
|
|
| 2. |
- Arp, Hans Peter H., et al.
(författare)
-
INFLUENCE OF HISTORICAL INDUSTRIAL EPOCHS ON PORE WATER AND PARTITIONING PROFILES OF POLYCYCLIC AROMATIC HYDROCARBONS AND POLYCHLORINATED BIPHENYLS IN OSLO HARBOR, NORWAY, SEDIMENT CORES
- 2011
-
Ingår i: Environmental Toxicology and Chemistry. - : Wiley. - 0730-7268 .- 1552-8618. ; 30:4, s. 843-851
-
Tidskriftsartikel (refereegranskat)abstract
- Contaminant levels in urban harbor sediments vary with contaminant emission levels, sedimentation rates, and sediment resuspension processes such as propeller wash. Levels of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) are decreasing in many urban harbors, as heavily contaminated sediments that accumulated during past decades are being buried by less-contaminated sediments. However, PAHs and PCBs remain a concern in areas where burial is slow or resuspension processes re-expose heavily contaminated older layers. Chronostratigraphic sediment core studies typically characterize contaminant level histories by using total sediment concentrations, C(sed), and do not determine the freely dissolved porewater concentrations, C(pw), which provide a better measure of bioavailability. Here both C(sed) and C(pw) profiles were established for PAHs and PCBs in dated sediment cores from diverse areas of Oslo Harbor, Norway. Sediment-porewater partitioning profiles were established alongside profiles of various sorbing carbonaceous phases, including total organic carbon (TOC), black carbon, and diverse carbonaceous geosorbents identified by petrographic analysis. Stratigraphic trends in carbonaceous phases and C(sed) could be associated with different industrial epochs: hydropower (post- 1960, approximately), manufactured gas (similar to 1925-1960), coal (similar to 1910-1925), and early industry (similar to 1860-1910). Partitioning was highly variable and correlated best with the TOC. Hydropower-epoch sediments exhibit decreasing C(sed) with time and a relatively strong sorption capacity compared with the manufactured-gas epoch. Sediments from the manufactured-gas epoch exhibit substantial PAH and metal contamination, large amounts of coke and char, and a low sorption capacity. Reexposure of sediments of this epoch increases risks to local benthic species. Implications on natural recovery as a sediment management strategy are discussed.
|
|
| 3. |
- Arp, Hans Peter H., et al.
(författare)
-
The presence, emission and partitioning behavior of polychlorinated biphenyls in waste, leachate and aerosols from Norwegian waste-handling facilities
- 2020
-
Ingår i: Science of the Total Environment. - : ELSEVIER. - 0048-9697 .- 1879-1026. ; 715, s. 1-12
-
Tidskriftsartikel (refereegranskat)abstract
- Even though production and open use of polychlorinated biphenyls (PCBs) have been phased out in Western industrialised countries since the 1980s, PCBs were still present in waste collected from different waste handling facilities in Norway in 2013. Sums of seven indicator-PCBs (I-PCB7:PCB-28, -52, -101, -118, -138, -153 and -180) were highest in plastic waste (3700 +/- 1800 mu g/kg, n=15), waste electrical and electronic equipment (WEEE) (1300 +/- 400 mu g/kg, n=12) and fine vehicle fluff (1800 = 1400 mu g/kg, n=4) and lowest in glass waste, combustibles, bottom ash and fly ash (0.3 to 65 mu g/kg). Concentrations in leachate water varied from 1.7 to 2900 ng/L, with higher concentrations found at vehicle and WEEE handling facilities. Particles in leachate water exhibited similar PCB sorption properties as solid waste collected on site, with waste-water partitioning coefficients ranging from 10(5)to 10(7) .I-PCB7 in air samples collected at the sites were mostly in the gas phase (100-24000 pg/m(3)), compared to those associated with particles (9-1900 pg/m(3)). In contrast, brominated flame retardants (BFRs) in the same samples were predominantly found associated with particles (e.g. sum of 10 brominated diethyl ethers, Sigma BDE10, associated with particles 77-194,000 pg/m(3)) compared to the gas phase (Sigma DE10 6-473 pg/m(3)). Measured gas-phase I-PCB7 concentrations are less than predicted, assuming waste-air partitioning in equilibrium with predominant waste on site. However, the gas-particle partitioning behavior of PCBs and BFRs could be predicted using an established partitioning model for ambient aerosols. PCB emissions from Norwegian waste handling facilities occurred primarily in the form of atmospheric vapor or leachate particles.
|
|
| 4. |
- Cornelissen, Gerard, et al.
(författare)
-
Large-Scale Field Study on Thin-Layer Capping of Marine PCDD/F-Contaminated Sediments in Grenlandfjords, Norway : Physicochemical Effects
- 2012
-
Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 46:21, s. 12030-12037
-
Tidskriftsartikel (refereegranskat)abstract
- A large-scale field experiment on in situ thin-layer capping was carried out in the polychlorinated dibenzodioxin, and dibenzofuran (PCDD/F) contaminated Grenlandsfjords, Norway The main focus of the,trial Was to,test the effectiveness of active caps (targeted thickness of 2.5 cm) consisting of powdered activated carbon (AC) mixed into locally dredged clean clay. Nonactive caps (targed thickness of 5 cm) consisting of clay without, AC as well as crushed limestone were also tested Fields with areas of 10 000 to 40 000 m(2) were established at 30 to 100 m water depth. Auxiliary shaken laboratory batch experiments showed that 2% of the applied powdered AC substantially reduced PCDD/F porewater concentrations, by >90% for tetra-, penta- and hexa-clorinated congeners to 60-70% for octachlorinated ones. In situ AC profiles revealed that the AC was mixed into the sediment to 3 to 5 cm depth in 20 months. Only around 25% of the AC was found inside the pilot fields. Sediment-to-water PCDD/F fluxes measured by in situ diffusion chambers were significantly lower at the capped fields than at reference fields in the same fjord, reductions being largest for the limestone (50-90%) followed by clay (50-70%), and the AC + clay (60%). Also reductions in overlying aqueous PCDD/F concentrations measured by passive samplers were significant in most cases (20-40% reduction), probably because of the large size of the trial fields. The AC was less effective in the field than in the laboratory, probably due to prolonged sediment-to-AC mass transfer times for PCDD/Fs and field factors such as integrity of the cap, new deposition Of contaminated sediment particles, and bioturbation. The present field data indicate that slightly thicker layers of limestone and dredged clay can show as good physicochemical effectiveness as thin caps of AC mixed with clay, at least for PCDD/Fs during the first two years after cap placement.
|
|
| 5. |
- Cornelissen, Gerard, et al.
(författare)
-
Remediation of Contaminated Marine Sediment Using Thin-Layer Capping with Activated Carbon-A Field Experiment in Trondheim Harbor, Norway
- 2011
-
Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 45:14, s. 6110-6116
-
Tidskriftsartikel (refereegranskat)abstract
- In situ amendment of contaminated sediments using activated carbon (AC) is a recent remediation technique, where the strong sorption of contaminants to added AC reduces their release from sediments and uptake into organisms. The current study describes a marine underwater field pilot study in Trondheim harbor, Norway, in which powdered AC alone or in combination with sand or clay was tested as a thin-layer capping material for polycyclic aromatic hydrocarbon (PAH)-contaminated sediment. Several novel elements were included, such as measuring PAH fluxes, no active mixing of AC into the sediment, and the testing of new manners of placing a thin AC cap on sediment, such as AC+clay and AC+sand combinations. Innovative chemical and biological monitoring methods were deployed to test capping effectiveness. In situ sediment-to-water PAH fluxes were measured using recently developed benthic flux chambers. Compared to the reference field, AC capping reduced fluxes by a factor of 2-10. Pore water PAH concentration profiles were measured in situ using anew passive sampler technique, and yielded a reduction factor of 2-3 compared to the reference field. The benthic macrofauna composition and biodiversity were affected by the AC amendments, AC + clay having a lower impact on the benthic taxa than AC-only or AC + sand. In addition, AC + clay gave the highest AC recoveries (60% vs 30% for AC-only and AC + sand) and strongest reductions in sediment-to-water PAH fluxes and porewater concentrations. Thus, application of an AC-clay mixture is recommended as the optimal choice of the currently tested thin-layer capping methods for PAHs, and more research on optimizing its implementation is needed.
|
|
| 6. |
- Eek, Espen, et al.
(författare)
-
Field Measurement of Diffusional Mass Transfer of HOCs at the Sediment-Water Interface
- 2010
-
Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 44:17, s. 6752-6759
-
Tidskriftsartikel (refereegranskat)abstract
- The sediment to water diffusive flux of PAHs and PCBs was measured under field conditions with a novel infinite-sink benthic flux chamber that deployed semipermeable membrane devices (SPMD) as a sorbing material. Fluxes were measured before and after in situ capping of sediments in Oslo Harbour with clean clay. The fluxes of native pyrene and PCB 52 from uncapped contaminated sediment measured with the flux chamber were 0.3-1.6 mu g m(-2) d(-1) and 2-8 ng m(-2) d(-1), respectively. Fluxes from the capped sediment were reduced by 93-97%. The in situ measured fluxes were compared to fluxes independently calculated from freely dissolved concentrations in pore water and overlying water, measured using equilibrium passive samplers, diffusive boundary layer (DBL) thickness, measured by an alabaster dissolution method and literature values of diffusion coefficients. Measured fluxes from the uncapped sediment agreed well with calculated fluxes, the median of the ratio of the measured flux over the calculated flux was 0.9 with an inter quartile range of 0.5-1.6.
|
|
| 7. |
- Kupryianchyk, Darya, et al.
(författare)
-
Treatment of sites contaminated with perfluorinated compounds using biochar amendment
- 2016
-
Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 142, s. 35-40
-
Tidskriftsartikel (refereegranskat)abstract
- Abstract Per- and polyfluorinated compounds (PFCs) have been attracting increasing attention due to their considerable persistence, bioaccumulation, and toxicity. Here, we studied the sorption behavior of three PFCs, viz. perfluorooctanesulfonic acid (PFOS), perfluorooctanecarboxylic acid (PFOA), perfluorohexanesulfonic acid (PFHxS), on one activated carbon (AC) and two biochars from different feedstocks, viz. mixed wood (MW) and paper mill waste (PMW). In addition, we explored the potential of remediating three natively PFC contaminated soils by the addition of AC or biochar. The sorption coefficient i.e. Freundlich coefficients Log KF, (μg/kg)/(μg/L)n, for the two biochars were 4.61 ± 0.11 and 4.41 ± 0.05 for PFOS, 3.02 ± 0.04 and 3.01 ± 0.01 for PFOA, and 3.21 ± 0.07 and 3.18 ± 0.03 for PFHxS, respectively. The AC sorbed the PFCs so strongly that aqueous concentrations were reduced to below detection limits, implying that the Log KF values were above 5.60. Sorption capacities decreased in the order: AC > MW > PMW, which was consistent with the material’s surface area and pore size distribution. PFC sorption to MW biochar was near-linear (Freundlich exponent nF of 0.87–0.90), but non-linear for PMW biochar (0.64–0.73). Addition of the AC to contaminated soils resulted in almost complete removal of PFCs from the water phase and a significant (i.e. 1–3 Log unit) increase in soil–water distribution coefficient Log Kd. However, small to no reduction in pore water concentration, and no effect on Log Kd was found for the biochars. We conclude that amendment with AC but not biochar can be a useful method for in situ remediation of PFC-contaminated soils.
|
|
| 8. |
- Meynet, Paola, et al.
(författare)
-
Effect of activated carbon amendment on bacterial community structure and functions in a pah impacted urban soil
- 2012
-
Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 46:9, s. 5057-5066
-
Tidskriftsartikel (refereegranskat)abstract
- We collected urban soil samples impacted by polycyclic aromatic hydrocarbons (PAHs) from a sorbent-based remediation field trial to address concerns about unwanted side-effects of 2% powdered (PAC) or granular (GAC) activated carbon amendment on soil microbiology and pollutant biodegradation. After three years, total microbial cell counts and respiration rates were highest in the GAC amended soil. The predominant bacterial community structure derived from denaturing gradient gel electrophoresis (DGGE) shifted more strongly with time than in response to AC amendment. DGGE band sequencing revealed the presence of taxa with closest affiliations either to known PAR degraders, e.g. Rhodococcus jostii RHA-1, or taxa known to harbor PAR degraders, e.g. Rhodococcus erythropolis, in all soils. Quantification by real-time polymerase chain reaction yielded similar dioxygenases gene copy numbers in unamended, PAC-, or GAC-amended soil. PAH availability assessments in batch tests showed the greatest difference of 75% with and without biocide addition for unamended soil, while the lowest PAH availability overall was measured in PAC-amended, live soil. We conclude that AC had no detrimental effects on soil microbiology, AC-amended soils retained the potential to biodegrade PAHs, but the removal of a available pollutants by biodegradation was most notable in unamended soil.
|
|
| 9. |
- Oen, Amy M. P., et al.
(författare)
-
In Situ Measurement of PCB Pore Water Concentration Profiles in Activated Carbon-Amended Sediment Using Passive Samplers
- 2011
-
Ingår i: Environmental Science and Technology. - : American Chemical Society (ACS). - 0013-936X .- 1520-5851. ; 45:9, s. 4053-4059
-
Tidskriftsartikel (refereegranskat)abstract
- Vertical pore water profiles of in situ PCBs were determined in a contaminated mudflat in San Francisco Bay, CA, 30 months after treatment using an activated carbon amendment in the upper layer of the sediment. Pore water concentrations were derived from concentrations of PCBs measured in two passive samplers; polyethylene (PE, 51 mu m thick) and polyoxymethylene (POM, 17 mu m thick) at different sediment depths. To calculate pore water concentrations from PCB contents in the passive samplers, an equilibrium approach and a first-order uptake model were applied, using five performance reference compounds to estimate pore water sampling rates. Vertical pore water profiles showed good agreement among the measurement and calculation methods with variations within a factor of 2, which seems reasonable for in situ measurements. The close agreements of pore water estimates for the two sampler materials (PE and POM) and the two methods used to translate uptake in samplers to pore water concentrations demonstrate the robustness and suitability of the passive sampling approach. The application of passive samplers in the sediment presents a promising method for site monitoring and remedial treatment evaluation of sorbent amendment or capping techniques that result in changes of pore water concentrations in the sediment subsurface.
|
|
| 10. |
- Okkenhaug, Gudny, et al.
(författare)
-
Antimony (Sb) and lead (Pb) in contaminated shooting range soils : Sb and Pb mobility and immobilization by iron based sorbents, a field study
- 2016
-
Ingår i: Journal of Hazardous Materials. - : Elsevier BV. - 0304-3894 .- 1873-3336. ; 307, s. 336-343
-
Tidskriftsartikel (refereegranskat)abstract
- Small-arm shooting ranges often receive a significant input of lead (Pb), copper (Cu) and antimony (Sb) from ammunition. The goal of the present study was to investigate the mobility, distribution and speciation of Pb and Sb pollution under field conditions in both untreated and sorbent-amended shooting range soil. Elevated Sb (19-349 mu g L-1) and Pb (7-1495 mu g Pb L-1) concentrations in the porewater of untreated soil over the four-year test period indicated a long-term Sb and Pb source to the adjacent environment in the absence of remedial measures. Mixing ferric oxyhydroxide powder (CFH-12) (2%) together with limestone (1%) into the soil resulted in an average decrease of Sb and Pb porewater concentrations of 66% and 97%, respectively. A similar reduction was achieved by adding 2% zerovalent iron (Fe) to the soil. The remediation effect was stable over the four-year experimental period indicating no remobilization. Water- and 1 M NH4NO3-extractable levels of Sb and Pb in field soil samples indicated significant immobilization by both treatments (89-90% for Sb and 89-99% for Pb). Results from sequential extraction analysis indicate fixation of Sb and Pb in less accessible fractions like amorphous iron oxides or even more crystalline and residual mineral phases, respectively. This work shows that amendment with Fe-based sorbents can be an effective method to reduce the mobility of metals both in cationic and anionic form in polluted shooting range soil.
|
|
