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Mitigation of Greenhouse Gases Emissions by Management of Terrestrial Ecosystem

Abstract

Carbon dioxide fluxes between ecosystems of the Earth are presented. It was shown that intensifying its absorption of terrestrial ecosystems by 3.2% would prove sufficient to neutralize carbon dioxide emissions from the combustion of fossil fuels and cement production. It was shown that Polish forests absorb 84.6 million tons of CO2/year, that is 26% of emissions from fossil fuel combustion and cement production, while agricultural crops absorb 103 million tons of CO2/year. Total carbon dioxide sequestration by forests and agricultural crops amounts to 187.5 million tons of CO2/year, which is tantamount to 59% of emissions from fossil fuel combustion and cement production. Forestation of marginal soils would further increase carbon dioxide absorption in Poland by 20.6 million tons of CO2/year. Moreover, if plants were sown in order to produce green manure - instead of leaving soil fallow - sequestration could still be boosted by another 6.2 million tons of CO2/year.

Open access
The Origin of Heavy Metals and Radionuclides Accumulated in the Soil and Biota Samples Collected in Svalbard, Near Longyearbyen

Abstract

Heavy metals and radioactive compounds are potentially hazardous substances for plants, animals and humans in the Arctic. A good knowledge of the spatial variation of these substances in soil and primary producers, and their sources, is therefore essential. In the samples of lichen Thamnolia vermicularis, Salix polaris and Cassiope tetragona, and the soil samples collected in 2014 in Svalbard near Longyearbyen, the concentrations of the following heavy metals were determined: Mn, Ni, Cu, Zn, Cd, Pb and Hg, as well as the activity concentrations of the following: K-40, Cs-137, Pb-210, Pb-212, Bi-212, Bi-214, Pb-214, Ac-228, Th-231 and U-235 in the soil samples. The differences in the concentrations of the analytes accumulated in the different plant species and soil were studied using statistical methods. Sea aerosol was indicated as the source of Pb, Hg, Cs-137, Pb-210 and Th-231 in the studied area. A relatively high concentration of nickel was determined in the biota samples collected near Longyearbyen, compared to other areas of Svalbard. It was supposed that nickel may be released into the atmosphere as a consequence of the local coal mining around Longyearbyen.

Open access
PVP Based Materials: Biodegradation in Different Environments

Abstract

The research deals with biodegradation of films prepared from polyvinylpyrrolidone and polylactic acid (PVP/PLA). Biodegradation of PVP/PLA films was supported by the following additives: 1-methyl-2-pyrrolidone, 1-octyl-2-pyrrolidone, acrylamide and N-acetyl-L-phenylalanine according to the previous study. The films were prepared by a solvent casting technique. Biodegradation was observed using the respirometric method in different environments. The films subjected to biodegradation were analyzed by scanning electron microscopy and Fourier transform infrared spectroscopy. It was found that the films are substantially degraded, but not in the biological way; PVP was quickly removed in presence of water because of its easy solubility. In contrast, this fact could support biodegradation of PLA, which becomes more available for microorganisms when PVP leaves PLA matrix.

Open access
The Use of Biological Indices for the Assessment of the River Quality (Ruda River, Poland)

Abstract

Recognition of the deteriorating conditions of rivers worldwide has called for increased efforts to improve the ecological quality of impacted river systems. This is particularly important in areas that have suffered from a significant impact of human pressure on the ecological status of water. Field studies were conducted in the Ruda River in an area that had undergone anthropogenic disturbances. The objectives of our survey were to test the biological metrics based on benthic macroinvertebrates at four study sites. Spring and autumn surveys of benthic invertebrates indicated that based on the BMWP and BMWP(PL) indices, water quality was higher in comparison with the value of Multimetric index at all of the sites that were studied. Our results revealed that the water quality was higher at the study sites that are located above the dam reservoir based on both the chemical and biological parameters. This study also indicated that both spring and autumn constitute appropriate periods for carrying out monitoring studies. The values of multimeric index indicated the same water quality (except for site 1) in both sampling periods. Anthropogenic transformations of a riverbed influence the flora and fauna and affect the ecological status of rivers.

Open access
The Use of LCA Method to Assess Environmental Impact of Sewage Sludge Incineration Plants

Abstract

Life Cycle Assessment (LCA) is one of the new, little more popular in Poland of elements of environmental management. In the world literature one can find many examples of the use of LCA but mainly for comparison purposes. The paper presents results of LCA analysis made on the basis of data from a running incineration of sewage sludge. Performing a thorough analysis of this process enables improved operational system, including through a better use of the resulting products of combustion, as well as determining the impact of the thermal treatment of sludge on the environment and compared the results with data from the literature. To date, in Poland has not been carried out environmental impact assessments and the process of thermal treatment of both sludge and waste, based on the assumptions of LCA.

Open access
The Use of Two-Diode Substitute Model in Predicting the Efficiency of PV Conversion in Low Solar Conditions

Abstract

The article presents theoretical foundations of a two-diode equivalent model of a photovoltaic cell/module (PV), together with calculation procedures. A physical interpretation of individual components of an equivalent model was presented. Its practical application in predicting efficiency of operation of various PV cells and modules in low insulation conditions was demonstrated. The obtained predictions were verified with the actual results of their operation in open space (outdoor). The practical suitability of the “model” in early detection of ageing phenomena, such as, for example, absorber degradation taking place in PV modules, was demonstrated. The article was prepared on the basis of the results of testing five different PV modules with various constructions, made of different materials and absorbers, such as: c-Si, mc-Si, CIS, a-Si_SJ, a-Si_TJ. The used measurement data were collected during the 16-year period of the experimental PV modules testing system operation in University of Opole, equipped with a data acquisition system.

Open access
Voltammetric Determination of Aclonifen at a Silver Amalgam Electrode in Drinking and River Water

Abstract

A method for the determination of pesticide Aclonifen (AC) in drinking and river water by differential pulse voltammetry (DPV) on a meniscus modified silver solid amalgam electrode (m-AgSAE) using solid phase extraction (SPE) as a cleanup and preconcentration procedure is described. The limit of detection (LOD) for direct DPV determination of AC in deionized water is 2.7·10-8 mol·dm-3. LOD for DPV determination of AC in tap water after SPE is 1.6·10-10 mol·dm-3, the recovery being 55%. LOD for the determination of AC in Vltava river water is 1.9·10-9 mol·dm-3, the recovery being 65%. Humic acids interfere with the determination in river water; this problem can be resolved by adjusting the pH of the extracted sample to 6. The advantages of this approach are high sensitivity, low LOD, quick and easy sample preparation and fast determination.

Open access
Application of Artificial Neural Networks to the Technical Condition Assessment of Water Supply Systems

Abstract

The paper explains a method for discerning the parts of a water supply system in need of renovation. The results are based on technical data collected over the last twenty one years, concerning more than two hundred sections of both renovated and nonrenovated pipelines. In the study, an appropriately prepared data set was used for training an artificial neural network (ANN) in the form of a multilayer perceptron (MLP). Further comparison between the responses of the trained MLP and the decisions made by human experts showed satisfactory consistency, although 15% of the database records produced certain discrepancies. The presented method can help create an expert system capable of supporting failure-free operation of a water distribution system.

Open access
Application of Neural Networks in Diagnostics of Chemical Compounds Based on their Infrared Spectra

Abstract

The paper presents possibilities of using the so-called „finger-print“ identification method and artificial neural network (ANN) for diagnosis of chemical compounds. The construction of a tool specifically developed for this purpose and the ANN, as well as the required conditions for its proper functioning were described. The identification of chemical compounds was tested in two different ways for proving correctness of the assumptions. First of all, initial studies were carried out with the objective to verify the proper functioning of the developed procedure for IR spectrum interpretation. The second research stage was to find out how the properties of artificial neural networks will satisfy identification or differentiation in case of spectra with very similar structures or for mixtures consisting of several chemical compounds. Interpretation of infrared spectra of mono-constituent substances was successfully performed for both - the training and test data. Interpretation process of infrared spectra of bi-component substances, based on the example of structurally related compounds obstructing identification process, should also be described as positive. The model was able to interpret spectra of mixtures, which were previously registered into the database. Unfortunately, the program is not always able to determine which chemical substances reflect their presence in the infrared spectrum of ternary mixtures. During the research tests, it was also noted that the more complex the structure of a substance being present in the mixture was, the more difficult the interpretation of the spectra to be carry out properly by the program was. On the other hand, positive results were obtained for mixtures of compounds with not so complex structure. It must be emphasized that the results so far are promising and more attention should be paid to them in further studies.

Open access
Application of Selected Methods of Black Box for Modelling the Settleability Process in Wastewater Treatment Plant

Abstract

The paper described how the results of measurements of inflow wastewater temperature in the chamber, a degree of external and internal recirculation in the biological-mechanical wastewater treatment plant (WWTP) in Cedzyna near Kielce, Poland, were used to make predictions of settleability of activated sludge. Three methods, namely: multivariate adaptive regression splines (MARS), random forests (RF) and modified random forests (RF + SOM) were employed to compute activated sludge settleability. The results of analysis indicate that modified random forests demonstrate the best predictive abilities.

Open access