The paper investigates the air quality in the urban area of Warsaw, Poland. Calculations are carried out using the emissions and meteorological data from the year 2012. The modeling tool is the regional CALMET/CALPUFF system, which is used to link the emission sources with the distributions of the annual mean concentrations. Several types of polluting species that characterize the urban atmospheric environment, like PM10, PM2.5, NOx, SO2, Pb, B(a)P, are included in the analysis. The goal of the analysis is to identify the most polluted districts and polluting compounds there, to check where the concentration limits of particular pollutants are exceeded. Then, emission sources (or emission categories) which are mainly responsible for violation of air quality standards and increase the adverse health effects, are identified. The modeling results show how the major emission sources – the energy sector, industry, traffic and the municipal sector – relate to the concentrations calculated in receptor points, including the contribution of the transboundary inflow. The results allow to identify districts where the concentration limits are exceeded and action plans are needed. A quantitative source apportionment shows the emission sources which are mainly responsible for the violation of air quality standards. It is shown that the road transport and the municipal sector are the emission classes which substantially affect air quality in Warsaw. Also transboundary inflow contributes highly to concentrations of some pollutants. The results presented can be of use in analyzing emission reduction policies for the city, as a part of an integrated modeling system.
Gala Lake National Park that has an international importance is one of the most important wetland ecosystems for Turkey. As same as many aquatic habitats, Gala Lake is under a significant anthropogenic pressure originated from agricultural activities conducted around the lake and from industrial discharges by means of Ergene River.
The aim of this study was to evaluate the sediment quality of Gala Lake and Irrigation Canal by investigating some toxic element accumulations (As, B, Ni, Cr, Pb, Cd, Zn and Cu) from a statistical perspective. Pearson Correlation Index (PCI) and Factor Analysis (FA) were applied to detected data in order to determine the associated contaminants and effective factors on the system. Potential Ecological Risk Index (RI) and Biological Risk Index based sediment quality guidelines (mERM-Q) applied to detected data in order to assess the ecological and biological risks of heavy metals in the ecosystem. Also Geographic Information System (GIS) technology was used to make visual explanations by presenting distribution maps of investigated elements.
According to the results of PCI, significant positive correlations were recorded among the investigated toxic elements at 0.01 significance level. According to the results of FA, two factors, which were named as “Agricultural Factor” and “Industrial Factor”, explained 86.6% of the total variance. According to the results of Potential Ecological Risk Index, cadmium was found to be the highest risk factor and according to results of Biological Risk Index, nickel and chromium were found to be the highest risk factors for Gala Lake and Irrigation Canal. As a result of the present study, it was also determined that heavy metal contents in sediments of Gala Lake National Park reached to critical levels and the system is intensively under effect of agricultural and industrial originated pollution.
The most common chemical’s spills in typical transportation accidents are those with petroleum products such as diesel fuel, the consequence of which is an extensive pollution of the soil. In order to plan properly fuel recovery from the soil, it is important to gain information about the soil depth which may be affected by pollutant and to predict the pollutant concentration in different soil layers. This study deals with the impact of basic atmospheric conditions, i.e. air temperature and humidity on the diesel fuel migration through the soil. The diesel fuel was spilled into columns (L = 30 cm; D = 4.6 cm) filled with sandy and clay soil samples, and its concentrations at various depths were measured after 11 days under various air temperature (20 and 40°C) and relative humidity (30–100%) conditions. The effects observed were explained by understanding physical processes, such as fuel evaporation, diffusion and adsorption on soil grains. The increase in temperature results in higher fuel evaporation loss and its faster vertical migration. The relative humidity effect is less pronounced but more complex, and it depends much on the soil type.
The decomposition of hydrocarbons using combined advanced oxidation methods is largely considered owing to abundant production of OH radicals and the potential economic advantages. In this study, the synergetic effect of ozonation on photocatalytic oxidation of chloroform and chlorobenzene over expanded graphite-TiO2&ZnO Nano composite was investigated. The effect of introduced ozone concentration and residence time was also examined on removal efficiency. The results showed that the removal efficiency was significantly enhanced by the combined system resulting from the additional oxidation process causing active species to be increased. Increasing the introduced ozone concentration which generates more reactive compounds had a greater effect on the removal efficiency than that of residence time. However, from the mineralization point of view, the residence time had a dominant effect, and the selectivity towards CO2 was dramatically declined when the flow rate increased. Based on these results, the combined system is preferred due to higher removal efficiency and complete mineralization.