The effects of irrigation with meat processing factory effluent (MPE) in combination with additions of paunch to three arable sites and one pasture site on soil chemical and microbial properties were investigated in fields surrounding a beef meat processing factory. A pasture site that had only received MPE was also sampled along with adjoining arable and pasture control fields that had never received MPE or paunch. Additions of MPE/paunch caused increases in electrical conductivity, exchangeable Na and K, exchangeable sodium percentage (ESP), extractable P, organic C, total N, microbial biomass C, and metabolic quotient and decreases in exchangeable Ca and Mg, pH, and the proportion of organic C present as microbial biomass. The structure and diversity of bacterial and fungal communities was measured by polymerase chain reaction–denaturing gradient gel electrophoresis of 16S rDNA and internal transcribed spacer-RNA amplicons respectively and catabolic diversity by analysis of catabolic response profiles to 25 substrates. Principal component analysis of catabolic response profiles clearly separated control from MPE/paunch-treated sites, and this was associated with greater catabolic responses to the carboxylic acids α-ketoglutaric, α-ketobutyric, L-ascorbic, and citric acid in the control. At the arable sites, application of MPE and paunch caused increases in bacterial, fungal, and catabolic diversity. Canonical correspondence analysis of the relationship between catabolic, bacterial, and fungal fingerprints and soil properties indicated that the main soil variables separating MPE/paunch treatments from controls were the higher organic C, ESP, and extractable P and a lower pH, exchangeable Ca, and Mg. It was concluded that, although long-term MPE/paunch additions induce soil salinity, sodicity, and acidity, in general, they cause an increase in the size, activity, and structural and functional diversity of in the soil microbial community.

Two Co oxide catalysts supported on natural zeolites from Indonesia (INZ) and Australia (ANZ) were prepared and used to activate peroxymonosulphate for degradation of aqueous phenol. The two catalysts were characterized by several techniques such as X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy (EDS) and N2 adsorption. It was found that Co/INZ and Co/ANZ are effective in activation of peroxymonosulphate to produce sulphate radicals for phenol degradation. Co/INZ and Co/ANZ could remove phenol up to 100 and 70 %, respectively, at the conditions of 25 ppm phenol (500 mL), 0.2 g catalyst, 1 g oxone and 25 C. Several parameters such as amount of catalyst loading, phenol concentration, oxidant concentration and temperature were found to be the key factors influencing phenol degradation. A pseudo first order would fit to phenol degradation kinetics, and the activation energies on Co/INZ and Co/ANZ were obtained as 52.4 and 61.3 kJ/mol, respectively. © 2013 Springer Science+Business Media Dordrecht.

Ammonia emission from broiler houses is a major concern because of its impacts on the environment. To reduce ammonia emissions, it is necessary to understand the fate of ammonia/um in the broiler waste. In broiler waste, uric acid and urea hydrolyze to ammonia (NH₃) and a fraction of NH₃ converts to ammonium (NH₄ ⁺) depending on pH and temperature. Further, NH₄ ⁺ undergoes solid–liquid partitioning and the ammonia fraction is partitioned among the solid, liquid, and gas phases in the waste. Ammonium partitioning between solid and liquid phases in broiler cake and litter were measured at pH of 4, 6, and 7. Ammonium adsorption increased with pH in both broiler litter and cake. Adsorption capacity of the litter was much lower than broiler cake. Six NH₄ ⁺ adsorption/desorption isotherms (linear, Langmuir, Freundlich, Temkin, Redlich–Peterson, and Toth) were evaluated. The isotherm that provided the best fit for partitioning NH₄ ⁺ in litter or cake for each pH value was selected by comparing up to six sets of parameters modeled using linear and nonlinear (with five error functions) regressions. Despite high R ² values obtained using linear regression, linearizing the models introduced an offset into the model reducing their accuracy. The sum of normalized error was used to select the most suitable parameter set for each isotherm. While the nonlinear error functions were the more suitable for developing parameter sets in broiler litter, for cake, linear regression generally provided the most optimum parameter sets. Whereas the Freundlich, linear, and Temkin isotherms were the most suitable for broiler litter for pH of 4, 6, and 7, respectively, for the cake, the linear isotherm was the most suitable for the entire range of pH evaluated. Overall, due to its simplicity, the linear isotherm seems suitable for partitioning NH₄ ⁺ in the adsorbed and dissolved phases for simulating nitrogen fate and dynamics in broiler waste more accurately.

The disposal of olive mill wastes (OMW) is considered as a major environmental problem worldwide, but especially for Mediterranean countries. Disposal in evaporation ponds or directly on soil is a common practice, which causes serious damages to soil and to the environment. The present study was performed in the framework of the LIFE project “Strategies to improve and protect soil quality from the disposal of Olive Mill Wastes in the Mediterranean region-PROSODOL” and one of its main objectives was the identification of appropriate soil parameters that could be used as soil indicators to assess soil quality at OMW disposal areas. For this, a well-designed soil sampling strategy was developed and implemented in Crete, South Greece at five OMW disposal areas. Many soil parameters were monitored bimonthly for a year. After statistical evaluation, eight soil parameters were selected as being appropriate soil indicators for OMW disposal areas, i.e., electrical conductivity, pH, organic matter, polyphenols, total N, exchangeable K, available P, and available Fe. Although many researchers have extensively studied the effect of OMW on soil quality, yet the identification of soil indicators to assess and monitor soil quality is an innovative issue and has never been studied before.

Petroleum hydrocarbon contamination of soil is an emerging environmental threat on the Earth due to possible toxic impact on different ecological receptors. The present study was mainly carried out to evaluate the phytotoxicity of long-term total petroleum hydrocarbon-contaminated soils by the toxicity end points obtained from three plant species Zea mays, Lactuca sativa L., and Cucumis sativus. The tested soil exerted phytotoxicity for all the evaluated end points of plants with dose-dependent relationship. The determined IC₅₀ indicates inhibition in root elongation as the most sensitive toxicity end point for L. sativa L., while inhibition in cross-section area of meristematic zone as the most susceptible and inhibition in seed germination as the least susceptible end points for both Z. mays and C. sativus. The tested root morphometric parameters confirm their applicability as novel toxicity end points. In addition, microcalorimetric analysis confirmed the applicability of inhibition in metabolic heat emission rate as a toxicity end point. Microcalorimetry can be applied to determine the exerted phytotoxic effect on seedlings. The present combined approach concludes that the phytotoxicity of the tested soil is species-specific and varies as follows: Z. mays < C. sativus < L. sativa L. The findings of this study may have implications in planning comprehensive phytotoxicity assessment for hydrocarbon-contaminated soils or screening plant species for phytoremediation program.

A novel immobilized visible light-active photocatalyst (TiO₂/polyvinyl alcohol after thermal treatment (T-PVA)/cordierite honeycomb (CHC)) was successfully prepared by a simple and convenient method combining sol–gel and thermal treatment using tetrabutyl titanate (TBOT) as the titanium source, polyvinyl alcohol (PVA) as the precursor of conjugated polymer, and CHC as the support. The synthesized photocatalyst was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, ultraviolet–visible diffuse reflectance spectroscopy, and field emission scanning electron microscopy. The results showed that PVA was dehydrated to produce conjugated unsaturated T-PVA. The T-PVA not only extended the response spectrum of TiO₂ to visible light region, but also strengthened the adhesion of TiO₂ to CHC. The TiO₂/T-PVA/CHC showed both outstanding adsorption properties and excellent photocatalytic performance under visible light on the decolorization of Rhodamine B. Over eight cycles, the photocatalyst continued to maintain perfect photocatalytic activity, showing good stability.

This paper provides a short overview of the main oxidation processes more commonly applied for the remediation of contaminated sites, with specific reference to their application for the in situ remediation of contaminated sites, i.e. In Situ Chemical Oxidation (ISCO). A review of the main patents issued on this topic shows the relevant contribution to the development of this technology in the last 20 years, especially in the USA. The still limited deployment of ISCO in other geographical areas may be improved by the increased acceptance of the technology that may come from the development of proper application guidelines based on accepted design criteria. The latter ones are also discussed in this paper with reference to the application of Fenton's treatment. © 2013 Springer Science+Business Media Dordrecht.

High mercury concentrations in freshwater fish from the Nordic region have been of concern for a long time. Ongoing monitoring of key ecological species occurs in these countries to follow the situation. Here, we investigated spatial and temporal trends in mercury concentrations in European perch (Perca fluviatilis) within the Swedish and Finnish aquatic environments, collated from national monitoring programmes collected between 1974 and 2005 (n = 5,172). Data were length and weight adjusted to remove perch size as a confounding factor. Temporal trend analyses and t tests comparing pre- and post-1996 mercury concentrations for each country (1974-1995; 1996-2005; perch adjusted to 200 g/25 cm), showed a significant decrease in mercury concentration in perch from Sweden (p < 0.001) and a possible increase in mercury concentration in perch from Finland (p < 0.001). No statistically significant geographical trends were seen. Average mercury concentrations exceeded both the current environmental quality standard (EQS) of 20 ng/g wet weight (ww) and a discussed EQS for the Nordic region of 200-250 ng/g ww. Despite large reductions in mercury use and production in these countries, concentrations in perch continue to be higher here than in other European areas, posing a continued environmental risk. © 2013 Springer Science+Business Media Dordrecht.

The use of aqueous suspension of nanoparticles of titanium dioxide for photocatalytic removal of pollutants is not suitable for industrial applications due to the inconvenient and expensive separation of nanoparticles of titanium dioxide for reuse. The nanosized titanium dioxide needs to be immobilized on the support for improving the efficiency and economics of the photocatalytic process. In the present paper, nanoparticles of titanium dioxide have been immobilized on the surface of the support using three different techniques. The immobilized films of titanium dioxide have been characterized using X-ray diffraction and scanning electron microscopy to notice any change in the phase composition and photocatalytic properties of the titanium dioxide after immobilization on the support. A photocatalytic test has been performed under similar reaction conditions to compare the photocatalytic performance of the films of immobilized titanium dioxide prepared using different techniques.

Soil vapor extraction (SVE) is one of the most effective remediation technologies for soil and groundwater contamination. Soil particles can be mobilized by air perturbation during SVE, resulting in the differentiation of porous media, which has not been well addressed. This paper developed a numerical method to study the flow pattern and quantify the change of porous media for the first time. Based on the mass equilibrium and Darcy’s law, a two-phase water–air flow model was constructed with integration of saturation, relative permeability, and capillary pressure during SVE. Relationship between porosity and saturation was deduced and coupled with the two-phase flow model for quantifying change of porous media in real time. Results reveal that both porosity and permeability increase sharply in the early stage of SVE then gradually to a quasi-steady state. These increases in vadose zone tapered off with distance from the SVE screen and the steady period occurred later as well. The influence radius of a single SVE well and the change degree in porosity and permeability of media were proportional to the extraction vacuum and the driving coefficient C, which is more sensitive than extraction vacuum according to the simulation results. Knowledge from this modeling exercise provides a useful tool to estimate the change of remediated zone and assess the environmental risk of remedial activities at real-world contamination sites.