Measurements of particle size distributions and PM2.5 from an urban background site in the Central Po Valley are analysed; the site is one of the medium–small-size cities in the central valley, without the direct influence of the metropolitan and industrial area of Milan and of the Adriatic Sea. The data comprise number concentration of particle with diameters ranging between 10 and 700 nm, PM2.5 and main meteorological variables from February to August 2008. Daily cycles of the observed pollutants are analysed, along with auto-correlation function for particle number concentration and principal component analysis (PCA) of all the available variables; finally, the diurnal pattern of PM2.5 low-, medium- and high-pollution events has been investigated. Total particle number concentration showed a daily pattern both in winter and summer, although different between weekdays and Sundays and with wider variations during the cold season. A daily cycle is present for the geometric mean diameter of nucleation mode particles in winter and of nucleation and Aitken mode particles in summer. PM2.5 showed a slight daily pattern for weekdays and Sundays, similar, but lagged, to total particle count cycle. Mixing layer depth resulted the main process controlling PM2.5, although also human activities contribute to PM2.5 concentration and allow some deposition and (re-)mobilisation at the first hours of the day and morning rush hour, respectively, while particle number concentration responds immediately to anthropogenic sources. PCA confirmed the dependence of particle number concentration also on meteorological variables, e.g. mixing layer height, wind speed or atmospheric pressure, showing the important influence of regional meteorology on local pollution conditions. Modena can be considered a representative test area of the effect of the meteorological regime for the Central Po Valley on atmospheric particle concentration patterns, characterised by steady high-background concentration.

Prediction of the sorption behavior of environmental pollutants is of utmost importance within the framework of risk assessments. In this work two approaches are presented with the aim to describe sorption of aromatic substances to geosorbents. First, analytical solutions of kinetic models were fitted to experimental data of batch sorption experiments with aniline and 1-naphthylamine onto animal manure-treated soil and the soil mineral montmorillonite. The models, accounting for equilibrium and nonequilibrium sorption coupled to transformation and/or irreversible sorption processes, could well reproduce the concentration course of the sorbates. Results suggest that the amounts transformed/degraded and irreversibly bound were higher for the soil than for the clay mineral. In the second part, quantum chemical calculations were performed on aniline and 1-naphthylamine interacting with acetic acid, acetamide, imidazole, and phenol as models of functional groups present in humic substances. Molecular modeling showed that formation of hydrogen bonds is the dominating binding mechanism in all modeled complexes, which are energetically very similar between aniline and 1-naphthylamine.

Pot culture experiments were conducted to study the remediation potentials of a newly found accumulator Kalimeris integrifolia Turcz. ex DC. under different cadmium (Cd) concentrations with same fertilizer level, as well as the same Cd dose under different fertilizer doses. At medium (100 g/kg) chicken manure level, Cd concentrations in roots, stems, leaves, inflorescences, and shoots of K. integrifolia grown in the soils contaminated with 2.5, 5, 10, and 25 mg/kg Cd significantly decreased (p < 0.05) in average by 23.8%, 29.9%, 24.0%, 30.1%, and 38.6%, respectively, when compared to those of the pots without addition of chicken manure. In contrast, the medium urea amendment level (1 g/kg) showed no effect on the bioaccumulated Cd concentrations of K. integrifolia regardless of the spiked Cd doses. However, Cd extraction capacities (micrograms per pot) of K. integrifolia shoots were significantly increased (p < 0.05) due to the gain in biomass (more than one- to twofolds) by the soil fertilizing effect of urea and chicken manure. Particularly, Cd extraction capacities (micrograms per pot) of K. integrifolia shoots amended by urea were higher than that of chicken manure. Under the condition of 25 mg/kg Cd addition, shoot biomasses of K. integrifolia were significantly increased (p < 0.05) with the amendment of chicken manure (50, 100, and 200 g/kg) and urea (0.5, 1, and 2 g/kg). As a result, the Cd extraction capacities (micrograms per pot) were increased in treatments even though soil extractable Cd concentrations were significantly decreased (p < 0.05) by amendment with chicken manure and maintained by urea addition. For practical application concerns, chicken manure is better used as phytostabilization amendment owing to its reducing role to extractable heavy metal in soil, and urea is better for phytoextraction.

Instrumented column tests are often used to assess the effectiveness of methods to prevent acid mine drainage (AMD). These tests are seldom duplicated, and this lack of duplicate can cast some doubt about their repeatability and reliability. This paper provides an analysis of column test studies (with duplicates) performed with a commonly used methodology. The paper presents the analysis of two multi-layer covers with capillary barrier effects in which the water retention layer was made of a non-plastic silt and of two cover scenarios involving a single-layer low sulphide cover. The first study compared the cover performance to limit AMD when different cover materials are used, while the second study compared the thickness of covers on cover performance. Statistical comparison between duplicates was made using available geochemical data, hydro-geotechnical data, and gas concentrations. Student’s t-test statistical tools and analysis of variances were used to determine the repeatability of the data. The results indicate that a good reproducibility of the column tests can be achieved with a good set-up methodology and rigorous control of the boundary conditions.

In mussels, stress signals such as heat, osmotic shock and hypoxia lead to the activation of the phosphorylated p38 mitogen activated protein kinase (pp38-MAPK). This stress activated protein has been efficiently used as a biomarker to several natural and anthropogenic stresses. However, what has not been tested is whether differences in gender or size can affect the response of this biomarker. The present study tested whether there was variation in the expression of pp38-MAPK in mussels Perna perna of different gender and size classes when exposed to natural stress conditions, such as air exposure. The results show that gender does not affect the expression of pp38-MAPK. However, size does have an effect, where mussels smaller than 6.5 cm displayed significantly (p < 0.05) lower levels of pp38-MAPK when compared to those larger than 7 cm. Mussels are one of the most used bioindicator species and the use of biomarkers to determine the health status of an ecosystem has been greatly increasing over the years. The present study highlights the importance of using mussels of similar size classes when performing experiments using stress-related biomarkers.

Environmental constrains and anthropogenic changes can contribute simultaneously to the limitation of plant performance in Mediterranean urban areas. Photosynthetic efficiency of Quercus ilex L. leaves from the urban area of Naples was evaluated by comparison with leaves from remote site (Vesuvius National Park). The photosynthetic performance of leaves with different age (current year [CY], 1- [1Y] and 2-year old [2Y]) was assessed by measurements of gas exchange, chlorophyll fluorescence and pigment contents. The photosynthetic activity at the urban site was higher than that at the remote site for the CY leaves, while the opposite was observed for the 1Y and 2Y leaves. The growth of Q. ilex trees was mainly sustained by the CY leaves at the urban site, whereas at the remote site the photosynthetic activity was not affected by leaf ageing. In the urban environment, Q. ilex leaves strongly decreased the photosynthetic performance with leaf ageing as highlighted by leaf gas exchanges, although the photochemistry did not show any significant change. The mature leaves of urban site drove the reductive power deriving from the photochemistry more in non-assimilative processes rather than in carbon assimilative ones, avoiding a strong decrease of PSII photochemical efficiency.

The purpose of this study was to determine the impacts of regional historical uranium mining activities within sediments of the Bowman–Haley reservoir of southwestern North Dakota. The extent of anthropogenic-influenced watershed impacts were quantified through the determination of sediment metals concentrations and metal enrichment factors to evaluate the potential of geochemically influenced As and U remobilization within the reservoir sediments. Sediment cores were collected and analyzed for total metal concentrations at five locations within the reservoir: Spring Creek delta, Alkali Creek delta, two locations within the North Fork of the Grand River confluence, and adjacent to the reservoir outfall. Pearson-moment correlations were used to establish inter-core metal correlations, while sediment enrichment factors were determined relative to background concentrations. Enrichment factor results suggest all sampling sites are classified as minor to moderately enriched for As and U. Metal behavior for the three reservoir inlets indicated similar metal loading sources and post-depositional behavior, while metals migration within the vicinity of the reservoir outlet appear to be controlled by geochemical and/or physical processes. For the reservoir outlet, As and U normalized to Al suggest the occurrence of vertical migration of As, while surface-bound U remobilization was apparent within the water column immediately above the sediments. Elevated U was found within the Spring Creek inlet, and appear attributed to historical uranium processing operations located in Griffin, North Dakota. While the reservoir As and U sediment concentrations may be considered low, their presence appears directly attributed to historical uranium mining activities within the Bowman–Haley reservoir watershed.

We tested how ecosystem structure (macroinvertebrate community and primary producers) and functions (leaf decay and open-water metabolism) are related to water quality in the Portneuf River, southeast Idaho. This river is polluted with excess nutrients and fine sediment and simultaneously demonstrates a range of hydrologic conditions due to a variety of groundwater and spring inputs. Macroinvertebrate abundance, functional feeding group composition, and diversity responded most to hydrology due to affinity of the invasive New Zealand mudsnail for spring-influenced conditions. Macrophytes were most abundant at spring-influenced sites, while benthic periphyton standing crop was highest at sites with highest nutrient concentrations. Leaf decay rates increased by 50% at spring-influenced sites and showed no response to 3-100-fold differences in nutrient concentrations. Finally, primary production measured via open-water metabolism was highest at spring-influenced sites, which tended to have low turbidity. Community respiration, however, was greatest at the site with the highest nutrient concentrations. Therefore, open-water metabolism was a useful indicator of water quality in this nutrient-polluted river, while invertebrate community structure and leaf decay did not reflect large differences in water quality among sites. Our findings suggest that structure and function metrics provide complementary information on biotic responses to water pollution and that these metrics should be used in concert to more fully understand and monitor biotic responses to water pollution and hydrologic alterations in streams and rivers.

Due to increased whole-tree harvesting in Swedish forestry, concern has been raised that a depletion of nutrients in forest soil will arise. The Swedish Forest Agency recommends compensation fertilization with wood ash to ensure that unwanted effects are avoided in the nutrient balance of the forest soil and in the quality of surface water. In this investigation, the chemistry of two first-order streams, of which one was subjected to a catchment scale treatment with 3 tonnes of self-hardened wood ash/ha in the fall of 2004, was monitored during 2003–2006. Large seasonal variations in stream water chemistry made changes due to ash application difficult to detect, but evaluating the ash treatment effects through comparison of the stream water of the treated catchment with the reference was possible via statistical tools such as randomized intervention analysis in combination with cumulative sum charts. The wood ash application did not yield any significant effect on the pH in the stream water and hence did not affect the bicarbonate system. However, dissolved organic carbon increased, a previously unreported effect of WAA, bringing about an increase of organic anions in the stream water. The wood ash application also induced significant increases for Ca, Mg, K, Si, Cl and malonate, of which K was most prominent. Although significant, the changes induced by the wood ash application were all small compared to the seasonal variations. As a tool to counteract acidification of surface waters, WAA seems to have limited initial effects.

Radon levels in two old mines in San Luis, Argentina, are reported and analyzed. The radiation dose and environmental health risk of 222Rn concentrations to both guides and visitors were estimated. CR-39 nuclear track detectors were used for this purpose. The values for the 222Rn concentration at each monitoring site ranged from 0.43 ± 0.04 to 1.48 ± 0.12 kBq m−3 in the Los Cóndores wolfram mine and from 1.8 ± 0.1 to 6.0 ± 0.5 kBq·m−3 in the La Carolina gold mine, indicating that, in this mine, the radon levels exceed up to four times the action level of 1.5 kBq m−3 recommended by the International Commission on Radiological Protection. The patterns of the radon transport process revealed that the La Carolina gold mine can be interpreted as a gas confined into a single tube with constant cross-section and air velocity. Patterns of radon activity, taking into account the chimney-effect winds, were used to detect tributary currents of air from shafts or larger fissures along the main adit of the Los Cóndores mine, showing that radon can be used as an important tracer of tributary air currents stream out from fissures and smaller voids in the rock of the mine.