Nutrient (C, N and P) and metal (Cr, Cu, Ni, Pb and Zn) content and dynamics of suspended and channel bed sediments were analysed within the rural Attert River basin (Luxembourg). This basin is representative of the main physiographic characteristics of the country, where there is currently little information available on the composition and dynamics of fluvial sediment. Stream bed fine-grained sediment samples (n = 139) collected during low flow conditions and time-integrated suspended sediment samples (n = 183) collected during storm runoff events (October 2005 to April 2008) in seven nested basins ranging from 0.45 to 247 km² were analysed. Nutrient and metal spatial patterns, temporal trends and the relationship between their content and storm runoff characteristics (e.g. maximum discharge and sediment concentration) were assessed. Results showed a high spatial and temporal variability, mainly associated with basin characteristics and local inputs. Higher values of total C were measured in the highly forested basins located in the northern part of the Attert River basin, whereas the highest values of total P were mainly associated with material coming from grassland and with the inflow of wastewater treatment plants (i.e. higher values of total P were measured in the southern part of the basin). The abundance of metals, not only in suspended but also in channel bed sediments, was generally as follows: Zn > Cr > Ni > Pb > Cu. Both nutrient and metal concentrations were at a maximum at the beginning of the wet season, after having been accumulated during the summer. These values tended to decrease during autumn and winter due to sediment mobilisation, and a higher flow capacity to transport coarser particle fractions from the sources. In general, concentrations of nutrients and metals on suspended sediment were negatively correlated with antecedent precipitation, total precipitation, total specific discharge and maximum discharge, which has been previously associated to a ’dilution’ effect during storm runoff events. Results show that both sediment sources and hydrologic events play an important role on the spatial and temporal variability of sediment-associated nutrient and metal contents.

Atmospheric carbonyl sulfide (COS) mixing ratios measured over 24 h during five summer campaigns (2003–2007) in a forest at the foot of Mt. Fuji, Japan (35°21′ N, 138°43′ E; 1,300 m above sea level, a.s.l.) and at the summit (3,776 m a.s.l.) were compared. COS levels were lower at the foot than at the summit during four out of five summer campaigns. The ratios of COS mixing ratios at the foot of Mt. Fuji to those at the summit ranged from 0.7 to 0.9. These results provide evidence of biological consumption of COS in the East Asian atmospheric boundary layer. We also measured the vertical profile of ambient COS below the forest canopy. These data showed a clear gradient of COS mixing ratio: in the lowermost 1 m of the boundary layer, COS mixing ratios decreased markedly downward. Two of the different kinds of vertical distribution of COS presented here support the role of soil as a sink of atmospheric COS described by previous research using dynamic enclosure experiments.

Nitrate contamination of groundwater represents a threat to human health. Many researchers have studied zerovalent iron as a mean to remediate nitrate contamination. However, the application of such method is limited by ammonium production. This work investigates the use of microscale iron particles in association with zeolitite, a natural material containing zeolite, to remove nitrate and ammonium from groundwater. The association of the two materials is shown to lower the nitrate concentration in both deionized water and groundwater under the limit suggested by the European Union and to significantly reduce the ammonium concentration. The method is potentially applicable in water filtration.

In the last few years, a great deal of research on soil has been carried out in order to develop a low-cost remediation method for reducing the environmental risks due to the pollution caused by heavy metals. In the light of this, the zeolitization achieved in soils mixed with coal fly ash could be a useful answer to reduce the amount and the mobility of metals in polluted areas. In this study, a selected soil treated with coal fly ash and artificially contaminated with Zn or Pb was used to synthesize zeolite at low temperature in laboratory and on a bench-scale experiments. Mineralogical data showed that the synthesis of zeolite X took place readily after the first month, and the amount of the newly formed mineral increased during the entire 1-year-long incubation period. The presence of toxic elements does not interfere with zeolite crystallization, whereas the chemical analysis indicated that a reduction in heavy metal availability takes place in the samples characterized by the presence of zeolite.

The use of azo dyes is popular in different branches of industry. Discharge of colourants to surface water cause harmful environmental effects. The aim of the present study was evaluation of effectiveness of diazo Evans blue decolourization by two Pseudomonas strains and estimation of process byproducts toxicity. In static conditions, both tested strains removed more than 85 % of dye after 48 h and completely decolorized samples after 120 h. Agitation had negative impact on Evans blue removal (less than 70 % of dye removed after 120 h). Ecotoxicological effects were different for both studied strains beside comparable decolourization effectiveness. Increase of zootoxicity was noticed for strain Sz6 and decrease from IV to III class was noticed for strain SDz3. Optimization of process conditions for the most promising strain SDz3 should be deeply examined.

Sodium chloride is the most often used chemical to malt ice and snow on the roads and has negative effects on the roadside environment. Searching for ways to improve the conditions for growth of trees and shrubs near the roads becomes an urgent matter. One such method of improving growth conditions for plants under salinity might be to use organic matter (green waste compost) and mycorrhizal fungi. This study studied the effect of application in soil different salts on several trees and shrubs growth in growing media. Also, effect of green waste compost and arbuscular mycorrhiza (AM) added to the growing medium was evaluated in terms of growth and K+, Ca+2, and Na+ uptake. The highest pH of the growing medium was noted when sodium carbonate was used. The pH ranged from 8.7 to 9.0 after eight doses of sodium carbonate. The pH of the growing medium was also significantly higher regardless of whether or not green waste compost or mycorrhizal fungi were used. The type of growing medium had a great effect on the growth of most of the trees, but among shrubs the growing medium was only important for Cornus alba, Sambucus nigra, and Spiraea vanhouttei. Growth of all these plants was much better under salinity when green waste compost or green waste compost with AM fungi was used. In all the cases, when salinity of the growing medium retarded growth of trees and shrubs, sodium chloride was the compound that had the strongest growth retarding effect. Leaf ionic composition was significantly affected by salinity in the growing medium, and in some cases also by micorhizal fungi. The type of growing medium had various effects on sodium uptake, depending on species. In most cases, the addition of green waste compost to the growing medium caused a greater amount of sodium in the leaves of tested plants. The use of mycorrhizal fungi had no effect on the uptake of sodium, compared to the control plants (without AM fungi).

The polysaccharidic moieties of three biosorbents (Douglas fir and argan tree barks and argan endocarp) were selectively oxidized, and the subsequent modified materials were tested for their ability to bind Pb(II) or Cd(II) from aqueous solutions. Chemical modifications consisted in two selective oxidations, alone or in combination, of the following groups: primary alcohols with NaOBr catalyzed by (2,2,6,6-tetramethylpiperidin-1-yl)oxidanyl, and vicinal diols with periodate/chlorite. The sodium chlorite oxidation step induced biosorbent degradation that led to a significant decrease of mass yield. Modified materials, characterized by FT-IR spectroscopy and measurement of surface acidity, were investigated for their adsorption capabilities of Cd(II) and Pb(II). Results were compared to the capabilities of crude materials using the Langmuir adsorption model in terms of affinity (b) and maximum binding capacity (q ₘₐₓ). Ion exchange properties were found better for lead than for cadmium before and after chemical modifications. Compared to crude barks, the best results were obtained for Douglas fir barks whose oxidation resulted in significant enhancements of q ₘₐₓ up to × 10 in the case of lead.

The relative transport and attenuation of bacteria, bacteriophages, and bromide was determined in a 5 m long × 0.3 m diameter column of saturated, heterogeneous gravel. The average pore velocity (V), longitudinal dispersivity (α x ), and total removal rate (λ) were derived from the breakthrough curves at 1, 3, and 5 m, at a flow rate of 24.8 L h−1. The experiments largely confirmed the differences in transport and attenuation patterns among bacteria, phages, and bromide, and between colloid-associated and “free” microorganisms, previously observed in a study using homogeneous pea gravel. Cultured Escherichia coli J6-2 cells were transported faster than phage MS2 and bromide, consistent with velocity enhancement of the larger particles. The evidence for velocity enhancement of phage MS2 compared with bromide was less conclusive, with some evidence of retardation of the phage as a result of adsorption–desorption processes in the finer media. On average, phage in sewage and adsorbed to kaolin particles were transported faster than free phage, suggesting that most sewage phage are adsorbed to colloids. However, average velocities of cultured and sewage E. coli differed far less, suggesting that most E. coli in sewage exist as individual (non colloid-associated) cells. There was no conclusive evidence that the wider pore size range in the heterogeneous mixture compared with pea gravel increased velocity enhancement effects. Removal rates of free phage were far higher than in the pea gravel, and were attributed to adsorption in the finer materials. Equivalent increases in removal of cultured and sewage E. coli and colloid-associated phage were attributed to straining in finer materials and settling in quiescent zones. Inactivation (μ) rates (determined in the pea gravel study) indicated little contribution to removal of either free or attached microorganisms. The results showed the importance of association with colloids in determining the relative transport of bacteria and viruses in alluvial gravels.

This paper presents for the first time the technological potential of novel Lantana camara-reinforced ethylene vinyl acetate (EVA) composites fabricated via the melt-blending technique. The composite and L. camara were characterized using X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and deferential scanning calorimeter. L. camara was found to drastically reduce the crystallinity of EVA from 44.3 % to a minimum of 1.16 %. Immersion of the composite specimens in de-ionised water showed that moisture absorption was less significant for composites with L. camara contents less than 15 % (w/w). A maximum sorption capacity of 1.20 mol% was recorded in 42 h which is remarkable considering the hydrophobic nature of EVA with 9 % vinyl acetate. L. camara and the composite removed 96 % and 88 % para-nitrophenol from water, respectively.

Biocovers are an alternative for mitigating fugitive and residual emissions of methane from landfills. In this study, we evaluated the performance of two experimental passive methane oxidation biocovers (PMOBs) constructed within the existing final cover of the St-Nicéphore landfill (Quebec, Canada). The biocovers were fed in a controlled manner with raw biogas and surface fluxes were obtained using static chambers. This enabled calculating mass balances of CH₄ and oxidation efficiencies (f ₒ_MB). Most of the time, f ₒ_MB ≥ 92 % were obtained for loadings as high as 818 g CH₄ m⁻² day⁻¹ (PMOB-2) and 290 g CH₄ m⁻² day⁻¹ (PMOB-3B). The lowest efficiencies (f ₒ_MB = 45.5 % and 34.0 %, respectively) were obtained during cold days (air temperature ~0 °C). Efficiencies were also calculated using stable isotopes (f ₒ_SI); the highest f ₒ_SI were 66.4 % for PMOB-2 and 87.3 % for PMOB-3B; whereas the lowest were 18.8 % and 23.1 %, respectively. However, f ₒ_SI values reflect CH₄ oxidation up to a depth of 0.10 m, which may partly explain the difference in regards to mass balance-derived efficiencies. Indeed, it is expected that a significant fraction of the total CH₄ oxidation occurs within the zone near the surface, where there is greater O₂ availability. The influence of the values of fractionation factors α ₒₓ and α ₜᵣₐₙₛ were also evaluated in this paper.