Mitochondrial phylogeography of the killifish Aphanius fasciatus (Teleostei, Cyprinodontidae) reveals highly divergent Mediterranean populations

We studied the genetic structure of the Mediterranean killifish Aphanius fasciatus. Analysis of the sequence variation in a 372-bp portion of the mitochondrial control region in 623 fish from 27 sampling sites along the species’ distributional range (Tyrrhenian coast, Sardinia, Sicily, Adriatic coast, Malta, Tunisia, and Greece) yielded 120 distinct haplotypes. Most of the haplotypes are unique, and only 15 % are shared among different populations. The high F _ST value (=0.80) suggests a strong population genetic structuring. The phylogenetic analysis based on Bayesian inference, maximum likelihood and maximum parsimony, and the median-joining network show a sharp separation of the Southeastern Sicilian populations (belonging to the Hyblean region) and of the fluvial Tunisian population of Rio Melah from the others. The Adriatic, the Eastern Sicilian, and the Greek populations are well differentiated, while the group of populations from the Central-Western Mediterranean does not show a clear pattern of differentiation. Our findings indicate that the current genetic structuring of A. fasciatus reflects historical geographical patterns occurring within the Mediterranean basin from the Late Miocene to the Pleistocene. The presence of divergent evolutionary entities in the Hyblean region and the Tunisian Rio Melah supports their inclusion as target areas for the conservation of A. fasciatus.     

Visible injury, crown condition, and growth responses of selected Italian forests in relation to ozone exposure

The impact of ozone on forest ecosystems in Italy is monitored within the CONECOFOR programme. Ozone levels are measured in 30 plots using passive samplers. Response parameters used are: crown condition (transparency), BAI (basal area increment), and visible symptoms on spontaneous vegetation. Levels of AOT40 are above the concentration-based critical level of 5 ppmh in all sites, but the evidence of impact on forest vegetation remains limited. Ozone is a predictor of crown transparency residuals in beech sites over two consecutive years, but the variance explained amounts to less than 10%. The relation between BAI reduction and ozone is even less certain. Transparency and BAI are more readily explainable in terms of ecological conditions of the site and climate fluctuations. The interpretation of visible symptoms is doubtful, and is conditioned by the prevailing ecological factors in the areas.     

Corrosion on cultural heritage buildings in Italy: A role for ozone?

Because of climatic reasons and of reduced concentrations of SO₂, ground-level ozone (O₃) is one of the main air pollutants in Southern Europe. Ozone levels are very high both in rural and urban locations. In the cities, O₃ can affect human health and materials. Regarding materials, most relevant is the exposure to pollutants of cultural heritage buildings. In particular, monuments registered on UNESCO's list of the world heritage require special monitoring. In Italy 34% and 97% of the territory is exposed to corrosion risk higher than the tolerable level for limestone and copper, respectively. The tolerable corrosion level for limestone and copper was also exceeded in the central area of Milan. In this area the tolerable O₃ concentration for copper was calculated. These concentrations (ranging between 30 and 40 μg/m³) cannot be exceeded at unchanged concentration of other pollutants to maintain corrosion levels below the tolerable ones.     

Preferential retention of POPs on the northern aspect of mountains

Soils are the main reservoirs of POPs in mountain ecosystems, but the great variability of the concentrations, also at small scale, leaves some uncertainties in the evaluation of environmental burdens and exposure. The role of the aspect of the mountain side and the seasonal variation in the contamination levels was analysed by means of several soil samples taken from central Italian Alps. A greater contamination content was present in northern soils with a mean ratio between the north vs. south normalised concentration of around a factor of 2 (North-South Enrichment Factor). Experimental factors agreed with theoretical calculations based on temperature-specific calculated K_sa values. From May to November consistent differences in normalised concentrations up to 5-fold were observed. A dynamic picture of the POP contamination in high altitudinal soils is derived from the data in this work, with spring-summer half-lives between 60 and 120 days for most of the compounds.     

Low to negligible photoactivity of lake-water matter in the size range from 0.1 to 5 μm

We found that the photochemical generation of reactive transients such as singlet oxygen and triplet states upon irradiation of different lake water samples is mostly accounted for by components smaller than 0.10 μm. Larger components often showed a much lower absorption and/or scattering of radiation compared with the smaller ones, with one exception where the minor to negligible photochemical activity of larger species was associated with significant radiation absorption/scattering. It is also shown that filtration of the lake water samples at 0.10 μm was able to effectively remove the suspended particles, differently from the usually suggested filtration at 0.45 μm.     

A microcosm system to evaluate the toxicity of the triazine herbicide simazine on aquatic macrophytes

This study evaluates the effects of the triazine herbicide simazine in an outdoor pond microcosm test system that contained two submerged rooted species (Myriophyllum spicatum and Elodea canadensis) and two emergent rooted species (Persicaria amphibia and Glyceria maxima) over a period of 84 days. Simazine was applied to the microcosms at nominal concentrations of 0.05, 0.5 and 5 mg/L. General biological endpoints and physiological endpoints were used to evaluate herbicide toxicity on macrophytes and the algae developing naturally in the system.Concentration-related responses of macrophytes and algae were obtained for the endpoints selected, resulting in a no observed ecologically adverse effect concentration (NOEAEC) at simazine concentrations of 0.05 mg active ingredient/L after 84 days. E. canadensis was the most negatively affected species based on length increase, which was consistently a very sensitive parameter for all macrophytes. The experimental design presented might constitute a suitable alternative to conventional laboratory single-species testing.     

Variability of ozone concentration in a montane environment,northern Italy

To evaluate the spatial variability of ozone concentrations, two studies were undertaken in the montane environment of Trentino region, northern Italy, in 2007. In the first study, a 225 km² area was considered. Here, a randomized design was used to evaluate the variability of ozone concentration at 1 and 225 km² scale. Measurements were carried out by passive samplers between May and June 2007. In a second study, the whole 6207 km² area of Trentino was considered. The area is covered by five grid cells of the European Monitoring and Evaluation Programme (EMEP). A systematic 15 × 15 km grid was used to allocate 15 passive samplers over the entire province, resulting into 1–4 samplers for each of the 5 EMEP grid cells (2500 km² each) overlapping the study area. Measurements were carried out between June and September 2007. Accuracy of passive samplers was checked by direct comparison with conventional ozone analysers. Significant differences (P = 0.034) were found in ozone concentration among 1 × 1 km quadrates within the 225 km² study area, while variability within the 1 × 1 km grid cells (coefficient of variation, CV′ = 0.12) slightly exceed the measurement error (CV′ = 0.08). At larger scales (225, 2500 and 6207 km²), ozone concentration shows much higher variability (CV′ from 0.18 to 0.28, with peak values at 0.40). Reported differences lead to very different AOT40 estimates even within the same EMEP grid cell. These findings suggest that 1 × 1 km resolution seems appropriate for ozone concentration modelling. On the other hand, significant sub-grid variation may exist at the resolution adopted by the EMEP model. Coupled with the likely variability of other important meteorological, soil and vegetation variables, our findings suggest that ozone risk assessment for vegetation based on large-scale modelled AOT40 and flux needs to be considered with great caution. The evidence reported in this paper asks for more detailed national-scale modelling, and the development of methods to incorporate local scale variations into large-scale models.     

The benefits of flue gas recirculation in waste incineration

Flue gas recirculation in the incinerator combustion chamber is an operative technique that offers substantial benefits in managing waste incineration. The advantages that can be obtained are both economic and environmental and are determined by the low flow rate of fumes actually emitted if compared to the flue gas released when recirculation is not conducted. Simulations of two incineration processes, with and without flue gas recirculation, have been carried out by using a commercial flowsheeting simulator. The results of the simulations demonstrate that, from an economic point of view, the proposed technique permits a greater level of energy recovery (up to +3%) and, at the same time, lower investment costs as far as the equipment and machinery constituting the air pollution control section of the plant are concerned. At equal treatment system efficiencies, the environmental benefits stem from the decrease in the emission of atmospheric pollutants. Throughout the paper reference is made to the EC legislation in the field of environmental protection, thus ensuring the general validity in the EU of the foundations laid and conclusions drawn henceforth. A numerical example concerning mercury emission quantifies the reported considerations and illustrates that flue gas recirculation reduces emission of this pollutant by 50%.     

Ozone and forests in South-Western Europe

The paper provides basic information about background, objectives and structure of O3SWE (Ozone at the permanent monitoring plots in South-Western Europe), an international co-operative project aimed at evaluating O3 concentrations, cumulative exposure, uptake and effects on forest vegetation in four countries of South-Western Europe (France, Italy, Luxenbourg, Spain and Switzerland). The project covers a total of 83 permanent plots of the EU and UN/ECE intensive forest monitoring programme and span over three years of investigation (2000-2002). The O3SWE project aims to demonstrate how, using data collected routinely in an intensive forest monitoring network, O3 exposure, flux and effects can be assessed and exceedances critically evaluated.     

Leaching and half-life of the herbicide tebuthiuron on a recharge area of Guarany aquifer in sugarcane fields in Brazil

This study was undertaken to evaluate the degradation and mobility of the herbicide tebuthiuron (N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N'-dimethylurea) in soil under field conditions, and its potential for leaching and groundwater contamination. A watershed, Espraiado, located over a recharge area in Brazil, was chosen for soil and water studies. At Espraiado, water samples were collected from seven wells at intervals of three months from March 2004 to June 2006 and analyzed for tebuthiuron. Other samples were taken from city wells located outside of the recharge area. To assess the potential movement to the aquifer, tebuthiuron was also applied to trial plots at the recommended label rate of 1.0 kg/ha a.i. in May of 2004, with and without sugarcane coverage, on sandy soil. Soil samples were collected during the years of 2004 and 2005, at depths intervals of 20 cm from soil surface down to 120 cm and analyzed for tebuthiuron at zero, 3, 30, 60, 90, 120, 150, 180, 240, and 300 days after application. There was no clear effect of sugarcane coverage on the tebuthiuron degradation in soils, but it moved faster into the soil where there was no cover. After 180 days there were no measurable residues in the soil, and tebuthiuron was not found below 40 cm depth in any time. Tebuthiuron had a half-life of 20 days under those conditions. No tebuthiuron residue was found in ground water samples at any sampling time.