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Abstract

The study presents the manners of determination of the Darcy friction factor λ for a homogenous hydromixture of alum sludge of varied hydration and temperature for the laminar flow zone. The rheological evaluation of the hydromixture as a viscoplastic body has been conducted with use of measurements of viscosity. The curves of flow were approximated with use of the generalized Vočadlo model. The Darcy friction factor λ of the pipeline was determined with use of the non-dimensional criterion λ(Regen) and λ(Re, He).
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Abstract

The subject of the research is one of the largest World’s mine tailings disposal sites, i.e. Żelazny Most in the Legnica-Głogów Copper Mining District (south-western Poland), where flotation tailings are poured out after copper ore treatment. The protective hydraulic barrier made of 46 vertical drainage wells was characterized and evaluated in view of reduction of major contaminants (Cl, Na, SO4, Ca) migrating from the facility to its foreground. The efficiency of groundwater protection was determined on the basis of a new approach. In applied method the loads of characteristic and commonly recognizable compounds, i.e. salt (NaCl) and gypsum (CaSO4) were calculated, instead their chemical components. The temporal and spatial variability of captured main contaminants loads as well as its causes are discussed. The paper ends with the results of efficiency analyses of the barrier and with respect to the predicted increase in contaminant concentrations in the pulp poured out to the tailings site.
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Abstract

Tropospheric ozone is one of the most reactive air pollutants, which causes visible injuries, as well as biomass and yield losses. The negative effect of ozone is cumulative during the growing season; hence crops are the most sensitive plants. Visible symptoms and biomass losses can cause economic losses. Tobacco plants have been recognized as one of the best bioindicators, but data on the cumulative effect of ozone on this species are limited. Results of an experiment with ozone-sensitive tobacco plants grown on sites varying in ozone concentration are presented in this paper. Two indices were used for data presentation of visible leaf injury degree. Higher solar radiation was the main cause of higher ozone concentration at the rural site. Higher tropospheric ozone concentrations were noted in 2010 in comparison to 2011, which was reflected in visible leaf injury. Canonical variate analysis did not reveal highly significant differences between sites, however, differences were observed in certain investigation periods. Moreover, higher leaf injury was noted at the rural site at the end of the experiment in both experimental years. This indicates the cumulative effect of ozone during the growing season. However, higher injury variability was noted at the urban site, even though lower ozone concentrations were noted there. Lower variability of injury at the rural site might suggest lack of influence of particulate matter and occurrence of higher injury even though lower ozone concentrations occurred. Better detection of ozone injury was shown by the first index based on three mean values.
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Abstract

The concentrations of Cu, Mn, Ni and Zn in the soil and litterfall, as well as influx of the elements to the soils with litterfall were studied in a mixed beech-pine-spruce stand in northern Poland during the years 2007–2009. Annual influx of litterfall to the soil amounted from 3.234 to 4.871 t/ha. Beech, pine and spruce litterfall contributed in total litterfall in 50.8−70.1%, 11.4−11.9% and 1.6−24.0% respectively. The following average annual concentrations of heavy metals in total litterfall during the 3-year study period were noticed: 2469.3–3469.2 mg Mn/kg, 153.6–160.8 mg/kg Zn, 8.0–14.3 mg Ni/kg and 5.0–6.8 mg Cu/kg. In general, the concentrations of Mn and Cu were higher in beech litterfall in comparison to pine and spruce. The contents of Zn and Ni in beech, pine and spruce litterfall were comparable. Annual influx of metals to the soil with litterfall was: 10341.6–14422.4 g/ha Mn, 460.3–748.1 g/ha Zn, 37.4–66.6 g/ha Ni and 20.2–31.8 g/ha Cu. The fluxes were higher for Mn, Zn and Ni, and comparable for Cu in relation to those observed in other beech, pine, spruce and mixed stands in northern Europe.
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Abstract

Contamination of soil with heavy metals has become a worldwide environmental problem, and receives great attention. In this study, we aim to investigate soil pollution level affected by an industrial district nearby. The total amount of typical heavy metals in the soils (Hengyang Songmu Industrial Park, Hunan Province, China) was analyzed. In addition, the fraction analysis and laboratory simulation leaching via different pH rainwater was carried out to study the migration and transformation of heavy metals. The main results show that the contents of Cu, Zn, Pb, Cr and Cd in the samples were higher than the soil background values in Hunan Province. The heavy metals forms, analyzed by sequential extraction method, show that the proportion of the unstable form of Cd, Zn and Pb was more than 50%. Igeo values indicate that the heavy metal pollution degree of soil sample #5 at the investigated area is recorded in the order of Cd(6.42), Zn(2.28), Cu(1.82), Pb(1.63), and Cr(0.37). Cu, Zn, Pb, Cr and Cd in this area could pose a potential leaching risk to the environment which may affect the food chain and constitute a threat to human health. It would be necessary to take steps to stabilize and monitor the heavy metals in soil.
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Abstract

This research was conducted to study the adsorption of ammonium ions onto pumice as a natural and low-cost adsorbent. The physico-chemical properties of the pumice granular were characterized by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Modeling and optimization of a NH4+ sorption process was accomplished by varying four independent parameters (pumice dosage, initial ammonium ion concentration, mixing rate and contact time) using a central composite design (CCD) under response surface methodology (RSM). The optimum conditions for maximum removal of NH4+ (70.3%) were found to be 100 g, 20 mg/l, 300 rpm and 180 min, for pumice dosage, initial NH4+ ion concentration, mixing rate and contact time. It was found that the NH4+ adsorption on the pumice granular was dependent on adsorbent dosage and initial ammonium ion concentration. NH4+ was increased due to decrease the initial concentration of NH4 and increase the contact time, mixing rate and amount of adsorbent.
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Abstract

The phytoextraction is a process that uses living plants for cleaning up the heavy metals from contaminated soil. The cadmium and lead contamination of soils results from the application of sludge or urban composts, fertilizers, pesticides, motorization, metallurgy, and different technological processes. In industrial terrain the content of cadmium and lead in soils has increased in the recent years. This study was undertaken to evaluate the potential of Amaranthus caudatus L. ‘Atropurpureus’ and Ricinus communis L. ‘Sanguineus Apache’ for phytoextraction of cadmium and lead. Two species of ornament plants, i.e. Amaranthus caudatus L. ‘Atropurpureus’ and Ricinus communis L. ‘Sanguineus Apache’, were planted in drainless containers in a substrate artificially polluted with cadmium and lead in order to evaluate their suitability for phytoremediation of soils or substrates contaminated with these metals. Cadmium was applied at increasing rates of 0, 1, 5 and 10 mg Cd∙dm-3 in the form of cadmium sulfate 3CdSO4∙8H2O, while lead was used at 0, 100, 500 and 1000 mg Pb∙dm-3 in the form of lead acetate (CH3COO)2Pb∙3H2O. The applied doses of cadmium and lead in the experiment reflected different degrees of soil pollution. After five months of growth it was found that Amaranthus caudatus L. accumulated the biggest concentrations of cadmium and lead in leaves and the lowest concentrations in inflorescences. Ricinus communis L. accumulated the highest concentrations of cadmium in stems, while the lowest concentrations in inflorescences, whereas the biggest concentration of lead was accumulated in inflorescences and the least lead was accumulated in leaves. The biggest reduction of cadmium and lead concentrations after the completion of the experiment was found in substrates, in which Amaranthus caudatus L. was grown. The tested species of ornamental plants may be used in the phytoextraction of cadmium and lead from soils contaminated.
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Abstract

The extracellular polymeric substance (EPS) produced from Rhizobium radiobacter F2, designated as EPSF2, was investigated as a biosorbent for the removal of Pb(II) and Zn(II) from aqueous solution. The optimum biosorption pH values were 5.0 for Pb(II) and 6.0 for Zn(II). Kinetics study revealed that the biosorption followed pseudo-first-order model well, and the equilibrium data fit the Langmuir model better. The adsorbed metal ions could be effectively desorbed by HCl. Desrobed EPSF2 regained 80% of the initial biosorption capacity after five cycles of biosorption-desorption-elution. These results demonstrated that EPSF2 could be a promising alternative for Pb(II) and Zn(II) removal from aqueous solution.
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Abstract

The paper presents the research results for the soils sampled from the area located in the eastern part of the Chodzieskie Lakes, between the Middle Noteć River Valley and the Wełna River Valley, the right tributary of the Warta River. The research involved 7 soil samples from the surface horizons, allocated to the cultivation of various plant species (cereals and vegetable crops). The following were determined in the soil material: the content of phytoavailable forms of selected heavy metals Zn, Cu, Pb, Ni, Fe and Mn, active and available to plants phosphorus against the activity of selected oxydo-reduction and hydrolytic enzymes. The soil under the vegetable crops showed a very high richness in phosphorus available to plants, which must have been related to an intensive fertilisation. There were identified relatively low contents of the available forms of the heavy metals investigated, the fact that points to their natural content in soil, which triggered the inhibition of neither the oxydo-reduction nor hydrolytic enzymes.
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Abstract

Rare earth metals including yttrium and europium are one of several critical raw materials, the use of which ensures the development of the so-called high technology. The possibility of their recovery in Europe is limited practically only to secondary materials such as phosphogypsum and electronic waste. The article presents the results of our research concerning the development of recovery technology of yttrium and europium from luminophore CRT used lamps. It describes the principle of separation of elements and the test results of cleaning the concentrate. It was shown that the costs of preparing the concentrate according to the proposed technology are lower than the phosphogypsum processing technology and the composition of the resulting product does not contain hazardous substances.
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Abstract

Predicted climate change may have negative impact on many environmental components including vegetation by increase of evapotranspiration and reduction of available water resources. Moreover, a growing global population and extensive use of water for irrigation and industry result in increasing demand for water. Facing these threats, quantitative and qualitative protection of water resources requires development of tools for drought assessment and prediction to support effective decision making and mitigate the impacts of droughts. Therefore, the Institute of Meteorology and Water Management, National Research Institute has developed and implemented a set of tools for the operational drought hazard assessment. The developed tools cover drought indices estimation, assessment of sensitivity to it formation and drought hazard prediction. They are streamlined into an operational scheme combined with data assimilation routines and products generation procedures. A drought hazard assessment scheme was designed to be implemented into the platform of a hydrological system supporting the operational work of hydrological forecast offices. The scheme was launched to run operationally for the selected catchments of the Odra River and the Wisla River basins. The crucial resulting products are presented on the website operated by IMWM-NRI: POSUCH@ (Operational System for Providing Drought Prediction and Characteristics) (http://posucha.imgw.pl/). The paper presents the scheme and preliminary results obtained for the drought event which began in August 2011.
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Abstract

The main objective of the study was to evaluate if macrophytes structure and trophic status of dam reservoir Kraśnik on a small lowland river Wyżnica are determined by phosphorous loadings. Studies were conducted seasonally in May, July and October during the years 2008-2009. Samples were taken at four sites: Site 1 - inflow of the Wyżnica River to pre-dam, Site 2 − pre-dam, Site 3 − dam reservoir and Site 4 - outflow of the Wyżnica River from dam reservoir. Physical and chemical parameters (temperature, Secchi disc depth, dissolved oxygen, pH, conductivity, total suspension, chlorophyll-a, TP and P-PO4) were measured in water samples. Together with water parameters there were estimated biomass of phytoplankton and species composition and biomass of emergent, floating-leaved and submerged macrophytes. Concentrations of TP, chlorophyll-a and Secchi disc depth were used to calculate trophic state index of Carlsson for dam reservoir and its pre-dam. Based on mean water current, mean residence time of water in dam reservoir and concentrations of TP and P-PO4 loadings (g m-2) flowing into dam reservoir with the Wyżnica River were calculated. The results showed visible negative effect of phosphorous loadings on both macrophytes composition and trophic state of the reservoir. The marked changes concerned soft vegetation. High P loadings (7.74 g m-2 of TP and 6.03 g m-2 P-PO4) during the spring of 2008 caused the disappearance of characeans meadows. In 2009, the presence of rigid hornwort (Ceratophyllum demersum L.), the species typical for eutrophic lakes was noted. This unrooted submerged plant uptakes dissolved orthophosphates directly from the water column. Values of Carlsson index (51.4 ≤ TSI ≤ 68.2) indicate the eutrophic state of dam reservoir Kraśnik. During summer season in dam reservoir there were observed algal blooms (biomass of phytoplankton exceed 10 mg WW dm-3) and low water transparency (Secchi disc depth ranged from 0.4 to 0.65 m). During the two-year studies in dam reservoir Kraśnik a high reduction of P loadings, mostly dissolved orthophosphates was observed. Dependently on season, reduction of P-PO4 loadings ranged from 52% (July 2008) up to 91% (May 2009). The reduction of TP was lower and reached values from 15% (May 2008) to 48% (July 2009).
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Abstract

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.
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Abstract

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.
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Abstract

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.
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Abstract

Applying pesticides to crops is one of the causes of water pollution by surface runoff, and chlorpyrifos, trifluralin and chlorothalonil are used respectively as insecticide, herbicide and fungicide for crop plants widely. To explore effects of three pesticides on aquatic organisms, superoxide dismutase (SOD) and glutathione S-transferase (GST) activities were determined after 24 h and 48 h exposure of D. magna with ages of 6–24 h to several low concentrations of chlorpyrifos (0.36, 0.72, 1.43, 2.86, 5.72 μg∙L−1), trifluralin (0.17, 0.33, 0.66, 1.33, 2.65 mg∙L−1) and chlorothalonil (0.09, 0.18, 0.36, 0.72, 1.43 mg∙L−1) respectively. Main reproductive parameters including first pregnancy time, first brood time, the number of first brood and total fecundity after 21 d exposures at the same concentrations of pesticides as described above were also measured. The results showed that the activities of GST increased in lower concentrations and decreased in higher concentrations after 24 h exposure to three pesticides, respectively. The activities of SOD showed the same changes after 48 h exposure. With the time prolonged, the activities of GST decreased while the activities of SOD increased. After 21 d exposure, the first pregnancy time and first brood time were delayed, while the number of the first brood and total fecundity per female decreased with increasing concentrations. These results corroborated that GST activity was more sensitive to those pesticides than SOD activity, and there was a significant relationship between total fecundity and pesticides-dose(r>0.94, n=6), GST activity after 48 h exposure and total fecundity after 21 d exposure (r>0.92, n=6).
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Abstract

Dye wastewater is one of typically non-biodegradable industrial effluents. A new process linking Fenton’s oxidation with biological oxidation proposed in this study was investigated to degrade the organic substances from real dye wastewater. During the combination process, the Fenton’s oxidation process can reduce the organic load and enhance biodegradability of dye wastewater, which is followed by biological aerated filter (BAF) system to further remove organic substances in terms of discharge requirement. The results showed that 97.6% of chemical oxygen demand (COD) removal by the combination process was achieved at the optimum process parameters: pH of 3.5, H2O2 of 2.0 mL/L, Fe(II) of 500 mg/L, 2.0 h treatment time in the Fenton’s oxidation process and hydraulic retention time (HRT) of 5 h in the BAF system. Under these conditions, COD concentration of effluent was 72.6 mg/L whereas 3020 mg/L in the influent, thus meeting the requirement of treated dye wastewater discharge performed by Chinese government (less than 100 mg/L). These results obtained here suggest that the new process combining Fenton’s oxidation with biological oxidation may provide an economical and effective alternative for treatment of non-biodegradable industrial wastewater.
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Abstract

This study investigates the influence of four imidazolium ionic liquids (ILs) present in wastewater on the activated sludge process. In addition, experiments with inactivated sludge to assess the capacity of this sorbent to remove ILs from the wastewater were conducted. It occurred that the presence of ionic liquids in wastewater reduces biomass growth and size of the sludge flocs. The strongest effect has been found for IL 6 (1-hexyl-2H-3-methyl-4,5-dimethylimidazolium iodide) with the longest alkyl chain length. Also, the degree of ILs removal increases with the alkyl chain length and decreases with the increase of initial concentration of ILs in wastewater. IL 6 reaches the highest degree of ILs removal from wastewater but inhibits the biomass growth and growth of sludge flocs in a greater extent than other tested compounds. Moreover, it was confirmed that newly synthesized ionic liquids can be adsorbed onto inactivated sludge. IL 6 could be adsorbed in a higher degree than other ionic liquids. This adsorption was described by Langmuir isotherm, whereas adsorption of other ionic liquids was described by Freundlich isotherm.
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Abstract

Antibiotics are a group of substances potentially harmful to the environment. They can play a role in bacterial resistance transfer among pathogenic and non-pathogenic bacteria. In this experiment three representatives of medically important chemotherapeutics, confirmed to be present in high concentrations in wastewater treatment plants with HPLC analysis were used: erythromycin, sulfamethoxazole and trimethoprim. Erythromycin concentration in activated sludge was not higher than 20 ng L−1. N-acetylo-sulfamethoxazole concentration was 3349 ± 719 in winter and 2933 ± 429 ng L−1 in summer. Trimethoprim was present in wastewater at concentrations 400 ± 22 and 364 ± 60 ng L−1, respectively in winter and summer. Due to a wide variety of PCR-detectable resistance mechanisms towards these substances, the most common found in literature was chosen. For erythromycin: erm and mef genes, for sulfamethoxazole: sul1, sul2, sul3 genes, in the case of trimethoprim resistance dhfrA1 and dhfr14 were used in this study. The presence of resistance genes were analyzed in pure strains isolated from activated sludge and in the activated sludge sample itself. The research revealed that the value of minimal inhibitory concentration (MIC) did not correspond with the expected presence of more than one resistance mechanisms. Most of the isolates possessed only one of the genes responsible for a particular chemotherapeutic resistance. It was confirmed that it is possible to monitor the presence of resistance genes directly in activated sludge using PCR. Due to the limited isolates number used in the experiment these results should be regarded as preliminary.
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Abstract

Fire has considerable impact on vegetation and organic soils properties. As we observed that the differences between vegetation of burnt and unburnt areas on the rich fen are visible 11 years after the fire, we assumed that the post-fire changes are long lasting, yet limited exclusively to the burnt areas. In order to check this hypothesis we studied spatial differentiation of physical and chemical properties of soils, and productivity capacities of burnt and unburnt areas in the fen in Biebrza National Park. We took soil samples from the neighboring burnt and unburnt areas, from the depth of 0–30 cm and 30–50 cm. We analyzed 21 parameters of the soils including: pH, ash content, moisture, bulk density, exchangeable K, Na, Ca, available P, N-NH4+, N-NO3−, total N, C, K, Na, Ca, Mg, Fe, P; and calculated C:N, C:P ratios. Surface layer of the burnt soils differed significantly from the unburnt soils in respect of 17 out of 21 parameters. The most pronounced difference was observed for available phosphorous (on average 6 times higher for the burnt soils). The differences in the deeper layer were mostly insignificant. The burnt areas were also characterized by twofold higher plant productivity than recorded for the unburnt areas. The influence of fire on peaty soils was long lasting but mostly limited to the surface layer of the soils. In the case of particular soil features, the post-fire differences were modified by advanced muck formation (moorshing) processes in the unburnt areas. Since the fire led to long lasting increase of fertility, the recovery of fen vegetation is unlikely.
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Abstract

People spend most of their time in indoor environments and, consequently, these environments are more significant for the contribution of the daily pollutant exposure than outdoors. In case of children, a great part of their time is spent at school. Therefore, evaluations of this microenvironment are important to assess their time-weighted exposure to air pollutants. The aim of this study was to assess the children exposure to bioaerosols at schools from two different types of areas, urban and rural. A methodology based upon passive sampling was applied to evaluate fungi, bacteria and pollens, simultaneously with active sampling for fungi and bacterial assessment. Results showed very good correlations between sampling methods, especially for summer season. Passive sampling methodologies presented advantages such as no need of specific and expensive equipment, and they allow achieving important qualitative information. The study was conducted in different periods of the year to study the seasonal variation of the bioaerosols. Fungi and pollen presented higher levels during the summer time whereas bacteria did not present a seasonal variation. Indoor to outdoor ratios were determined to assess the level of outdoor contamination upon the indoor environment. Levels of fungi were higher outdoor and bacteria presented higher concentrations indoors. Indoor levels of bioaerosols were assessed in primary schools of urban and rural areas, using the active method along with a passive sampling method. Very good correlations between methods were found which allow the use of the passive sampling method to supply important and reliable qualitative information of bioaerosols concentrations in indoor environments. Seasonal variation in bioaerosols concentrations were found for fungi and pollen. Concentrations of fungi and bacteria above AMV (Acceptable Maximum Value) were found for most of the studied classrooms showing the importance of this microenvironment for the high exposure of children to bioaerosols.
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Abstract

The possibilities of remote sensing techniques in the field of the Earth surface monitoring and protection specifically for the problems caused by petroleum contaminations, for the mapping of insufficiently plugged and abandoned old oil wells and for the analysis of onshore oil seeps are described. Explained is the methodology for analyzing and detection of potential hydrocarbon contaminations using the Earth observation in the area of interest in Slovakia (Korňa) and in Czech Republic (Nesyt), mainly building and calibrating the spectral library for oil seeps. The acquisition of the in-situ field data (ASD, Cropscan spectroradiometers) for this purpose, the successful building and verification of hydrocarbon spectral library, the application of hydrocarbon indexes and use of shift in red-edge part of electromagnetic spectra, the spectral analysis of input data are clarified in the paper. Described is approach which could innovate the routine methods for investigating the occurrence of hydrocarbons and can assist during the mapping and locating the potential oil seep sites. Important outcome is the successful establishment of a spectral library (database with calibration data) suitable for further application in data classification for identifying the occurrence of hydrocarbons.
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