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Variability of Oxygen-Thermal Conditions in Selected Lakes in Poland

Abstract

Dissolved oxygen in water (DO) is one of the primary parameters determining its quality. It remains in close relation to water temperature. The article presents results of DO and water temperature measurements performed for five stratified lakes in Poland in the years 2007-2014. The measurements were performed with monthly frequency in the summer half-year (May-October) in the deepest place of each of the lakes. The compared data show the complex character of the course of both of the parameters. The analysis of depth profiles revealed the prevalence of a decreasing tendency, or no tendency was recorded - both in the case of DO and water temperature. Due to the incoherent character of the water in the case of stratified lakes, a more detailed comparison was performed, referring to changes occurring in zones developed during summer stratification. It was determined that the temperature of the epilimnion was directly dependent on air temperature, and in all cases it showed an increasing tendency. Simultaneously, along with an increase in temperature, in the majority of cases, DO concentration in the zone decreased. In reference to the waters of the hypolimnion, increasing, decreasing, and no tendencies were recorded. The above distribution is determined by individual factors of the lakes - morphometry, trophic status, groundwater alimentation, etc. Several years of measurements of DO and water temperature in depth profiles of several lakes in Poland constitute valuable information on the current transformations of the environment of this part of Europe. In the future, the information can provide the basis for long-term analyses over the next decades, enriching global knowledge on those parameters of key importance for water ecosystems.

Open access
Adaptation of Selected Ectomycorrhizal Fungi to Increased Concentration of Cadmium and Lead

Abstract

Plants together with water and minerals actively take from the soil heavy metals such as cadmium and lead. The negative role of ions of these metals on plant growth and development depends not only on their concentration in the soil, but also on a number of factors that may affect the transport of minerals from the soil to the roots. The harmful effects of xenobiotics getting from the soil to the plants are limited by the organic compounds contained in the soil, soil structure and pH. Particularly noteworthy are biotic factors, such as bacteria and fungi which greatly limit the translocation of heavy metals. Stream of new scientific reports show that the symbiotic combination of fungi with plant roots so called mycorrhizae is a factor that may be important in reducing the impact of soil contamination by heavy metals. Mycorrhiza by filtering solutions of water and mineral salts stop a considerable amount of heavy metals in the internal mycelium or on its surface. It was proved that plants with properly formed mycorrhiza grow better in hard to renew lands, such as salty, sterile soils contaminated with industrial waste. Questions to which answer was sought in this study are: 1) whether mycorrhizal fungi for many years growing in the contaminated areas have managed to adapt to these adverse conditions and 2) do the same species derived from clean areas are less resistant to contamination by heavy metals? Stated problems tried to be solved based on the fruiting bodies of fungi collected from ectomycorrhizal fungi picked from the areas contaminated by industrial emissions and areas free of contamination. The interaction of cadmium and lead ions on the growth of mycelium was examined by plate method and binding of heavy metals in fruiting structures of fungi were done by colorimetric method with use of methylene blue. It has been shown that the fungal resistance, even of the same species, to high concentration of heavy metals varies depending on the origin of symbiont. Isolated fungi from contaminated areas are better adapted to high concentrations of xenobiotics. Ability to bind cadmium and lead to fruiting bodies of fungi varies.

Open access
Assessment of the Reliability-Cost Efficiency of the Pumping Subsystems at Water Treatment Plant

Abstract

In last years all countries of the European Union experience decrease of water consumption. What is worse, in most cases large European water treatment plants (WTP) have been design and built decades ago, when water consumption was much higher than nowadays. It is a challenging task to adjust WTP’s capacity to the current water demand as it is associated with costs and safety issues. Minding that fact, authors decided to propose an new authorial methodology of combined reliability-cost efficiency assessment for water supply system with exceeded redundant capacity, based on new index - unit indicator of reliability-cost efficiency. It included both reliability and costs aspects. It was decided to present the new method on example of the pumping subsystems working for WTP in Poland. The research was based on Activity-Based Life Cycle Costs (AB-LCC) methodology together with two-parametric reliability evaluation. Using real operational and financial data an application of proposed authorial reliability-cost indicator was presented. The reliability-cost efficiency assessment allowed to present how operation of each pumping subsystem influenced global operational costs of WTP. This information is essential for decision-making process for rational management of technical facilities.

Open access
Chemical Degradation of PCDD/F in Contaminated Sediment

Abstract

Due to the extreme toxicity of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F), the remediation of PCDD/F aquifer source zones is greatly needed; however, it is very difficult due to their persistence and recalcitrance. The potential degradability of PCDD/F bound to a real matrix was studied in five systems: iron in a high oxidation state (ferrate), zero-valent iron nanoparticles (nZVI), palladium nanopowder (Pd), a combination of nZVI and Pd, and persulfate (PSF). The results were expressed by comparing the total toxicity of treated and untreated samples. This was done by weighting the concentrations of congeners (determined using a standardized GC/HRMS technique) by their defined toxicity equivalent factors (TEF). The results indicated that only PSF was able to significantly degrade PCDD/F. Toxicity in the system decreased by 65% after PSF treatment. Thus, we conclude that PSF may be a potential solution for in-situ remediation of soil and groundwater at PCDD/F contaminated sites.

Open access
The Effect of Hemp Essential Oil on Mortality Aulacorthum Solani Kalt. And Tetranychus Urticae Koch

Abstract

Investigations concerning the effect of hemp oil on mortality of the foxglove aphid (Aulacorthum solani Kalt.) and the two spotted spider mite (Tetranychus urticae Koch) were conducted in the years 2014-2015. The tested essential oil was produced at the Institute of Natural Fibers and Medicinal Plants in Poznan. It was obtained by steam distillation of fresh panicles of Polish hemp cultivars, Beniko, Bialobrzeskie and Silesia, with low cannabinoid contents, including THC (max. 0.2% plant fresh matter). The effect of essential oil on the investigated pests was determined following the application of aqueous emulsion solution at 0.02, 0.05 and 0.1%. Mortality of agrophages was determined 24, 48 and 72 h after treatment. In this study a very high efficacy of the essential oil produced from hemp panicles was found in the reduction of population size of the foxglove aphid (A. solani). Already at 24 h after its application at a concentration of 0.1% pest mortality rate was 98.20%, while after 48 h it reached 100%. A significant, although much lesser effect of oil on the aphid population was recorded when applying it at 0.05%, with the mortality rate of the true bug after 72 h amounting to 57.33%. Essential oil also showed an effect on the two spotted spider mite (T. urticae). Following the oil application, irrespective of its concentration, a significant effect on mite mortality was observed. Its action was the strongest at its highest concentration, ie 0.1%, while mortality of the pest at 24, 48 and 72 h after treatment was 83.28, 95.83 and 98.72%, respectively.

Open access
Evaluation of Biogas Production and Usage Potential

Abstract

The aim of the research is the development of theoretical and methodical bases for determining the feasibility of plant raw materials growing for its further bioconversion into energy resources and technological materials to maximize profit from business activities. Monograph, statistics, modelling and abstract logical methods have been used during the research. Directions of biogas usage have been examined. Biogas yields from different crops have been analyzed. It has been determined that high methane yields can be provided from root crops, grain crops, and several green forage plants. So, forage beet and maize can provide more than 5,500 m3 of biogas per hectare. Attention is paid to the use of by-products of biogas plants, especially carbon dioxide. Carbon dioxide is an important commodity and can increase profitability of biogas plant operating. It can be used for different purposes (food industry, chemical industry, medicine, fumigation, etc). The most important parameters of the biogas upgrading technologies have been analyzed. If output of an upgrade module is more than 500 nm3/h, investment costs of different available technologies are almost equal. According to experts, it is economically feasible to use anaerobic digestion biogas systems to upgrade biomethane provided their performance is equivalent to 3,000 litres of diesel fuel per day. The economic and mathematical models have been suggested to determine the feasibility of growing plant materials to maximize the gross profit. The target function is the maximum gross income from biogas utilization. It has the following limitations: annual production of biogas, consumption of electricity, heat and motor fuels. The mathematical model takes into account both meeting own requirement and selling surplus energy resources and co-products including carbon dioxide. In case of diesel fuel substitution, an ignition dose of diesel fuels has been considered. The algorithm for making a decision on construction of a biogas plant has been offered.

Open access
Influence of Parameterization of Soil Processes on Meteorological Forecasts of Vertical Profiles

Abstract

Soil and atmosphere boundary layer (ABL) interact with each other and influence physical processes in soil and atmosphere. Quality of numerical weather forecast depends on good mapping of complex soil process (microphysics processes in soil, fluid dynamics in porous media, soil dynamics, water cycle in soil and soil-plant-water relation, thermal processes in the soil etc.) in parameterization soil schemes. Current parameterizations of soil physical processes in TERRA_ML (multilayer soil module of the COSMO meteorological model) were prepared 30 years ago for numerical model with poor resolution. Nowadays operationally numerical models work with much better resolution. So, previous parameterization must have been improved or prepared from the beginning if it is expected improvement quality of numerical weather forecast. The influence of changing parameterization of water flux through the soil for “bare soil” case on vertical meteorological profiles is presented in this paper. This influence can be seen not only in weather forecasts, but also in any areas where the results of meteorological model(s) are used, like decision support systems in emergency situations or modeling of dispersion of air pollutants.

Open access
Influence of Reservoirs on the Concentration of Nutrients in the Water of Mountain Rivers

Abstract

The aim of the analysis was to demonstrate the role of reservoirs in shaping nutrient content (nitrates NO3 - and phosphates PO4 3- as well as ammonia NH4 +) in the waters of mountain rivers. Three Carpathian rivers with reservoirs in their courses were selected for the study: the Ropa River (Klimkowka reservoir), the Dunajec River (the Czorsztyn-Sromowce Wyzne reservoir complex) and the Raba River (Dobczyce reservoir). The basic criteria for the selection of the study objects for the investigation were: similar hydrological regime of the rivers and diverse parameters and functions of the storage reservoirs. The analysis of nutrient concentration was based on a long-term series of measurements (2004-2013). The reservoirs investigated generally contribute to an increase in nitrates in the rivers flowing below the reservoirs in particular months. The role of reservoirs in shaping phosphate and ammonia levels was not as evident as in the case of nitrates. The reservoirs are merely one of numerous factors that contribute to nutrient levels in the water of the mountains rivers. In the light of the analysis of nutrient concentrations in the surface water tested, it may be concluded that the reservoirs do not cause a clear and permanent deterioration of river water quality.

Open access
Influence of Treated Sewage Discharge on the Benthos Ciliate Assembly in the Lowland River

Abstract

This paper presents results of the studies of ciliate assemblage in benthos of lowland river influenced by sewage discharged from the municipal wastewater treatment plant. During the presented research the 47 ciliate species, including 45 species from the benthos of the river and 18 from the activated sludge of aeration chamber were identified. Only two species registered in the activated sludge were not observed in the river. Against the background of the lowest number of species in the point located in the distance of 50 m below the discharge of sewage the maximum amount and biomass of these species were observed. Whereas, 200 m below the discharge the decrease in number and biomass of ciliate to the level noted for location before the discharge was observed. Thus, generalizing, one may state that influence of municipal WWTP sewage discharge for ciliate assemblage in the river’s benthos was clearly visible but local.

Open access
Simulation Model of Contamination Threat Assessment in Water Network Using the Epanet Software

Abstract

The aim of this study is to assess the risk of failure of group water network in case of raw water contamination. The analysis was based on qualitative simulation performed in hydraulic water network model developed in the EPANET software. It was focused on the quantitative description of the consequences of chemically contaminated water. The methodology of risk assessment relies in determining the consequences of the supply water containing contamination threatening the health and lives of water consumers. The research methodology is as follows: development of a hydraulic model of the water pipeline and it’s hydraulic verification, computer simulations of contamination propagation, calculating the dose delivered to the i-th section of the water supply system supplying water to Ni recipients and the mass of a substance that enters the body li. The simulation results indicate the spread of contamination that after 24 h covered most of the area supplied with water. The load delivered to the resident obtaining water from the i-th section of the water supply network, Li/Ni, was up to 18 g·d-1, at least 15 g·d-1 was received by 34.9% of the population, 10-15 g·d-1 by 12.5% of the residents, 5-10 g·d-1 by 10.7% of the residents, 0-5 g·d-1 by 41.7% of the residents and uncontaminated water was delivered to only 13.3% of the consumers. The dose taken by the statistical consumer (calculated as for adults) l is up to 0.8 g for Li/Ni = 18 g·d-1 and is proportional to Li/Ni.

Open access