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Bacillus subtilis BS-2 and Peppermint Oil as Biocontrol Agents Against Botrytis cinerea

Abstract

The purpose of this study was to assess the activity of Bacillus subtilis BS-2 and peppermint oil against Botrytis cinerea. In this study parameters such as the age and the density of the bacterial culture and the incubation temperature were taken into consideration. Furthermore, the cellulolytic activity of the bacterium was determined. The effect of peppermint oil was evaluated at a concentration range of 0.5-4.0 %. The research was conducted with a dual culture plate method. The influence of B. subtilis BS-2 and peppermint oil on the growth of B. cinerea was evaluated based on the growth rate index. It was noted that the bacterial culture occurred at an initial density of OD 560 = 1.0, cultivated at 30 °C for 48 hours demonstrated the strongest antagonistic effect (57.07 % inhibition). Furthermore, it was observed that the highest cellulolytic activity occurred on the bacteria incubated for 48 hours at 37 °C. The effect of mint oil, at the lowest concentration of 0.5-1.0 %, was much weaker on bacterial activity (1.1-12.1 % inhibition). The highest concentration (4.0 %) of mint oil caused the maximum inhibition (31.9 %) of the mycelial growth. B. subtilis BS-2 may be environmental-friendly alternatives for protecting plants against B. cinerea

Open access
Characterisation of Municipal Sewage Sludge as a Soil Improver and a Fertilizer Product

Abstract

In this study, we have determined the main important physical and chemical properties of municipal sewage sludge and compared them to the requirements of the Finnish Fertilizer Product Act and Fertilizer Product Decree in order to assess the potential utilization of this by-product as a fertilizer. Except for Hg (1.4 mg/kg d.m.), the total concentrations of Cd, Cu, Ni, Pb, Zn, Cr and As in our sewage sludge were lower that the Finnish maximum permissible heavy metal concentrations for sewage sludge used as a fertilizer products. However, the sewage sludge may be utilized as a soil improver, a growing media or as a fertilizer product in landfill sites (e.g. surface structures) or in other closed industrial areas, because the above mentioned Finnish limit values are not applied at these sites. If the sewage sludge is to be utilized in these kinds of areas, an environmental permit may be needed. According to BCR-extraction, the lowest release potential (solubility) from the sample matrix was observed for sulphur (58.4 %) and the highest for Cd (100 %).

Open access
Comparative Review of Artificial Light Sources for Solar-Thermal Biomass Conversion Research Applications

Abstract

In recent years solar-thermal methods of waste biomass conversion are promptly gaining on attention. For researchers working in areas that suffer from lack of natural solar power, the choice of proper solar simulator for the study is crucial. Solar simulator consist of artificial light source enclosed in proper housing with optical and cooling system, powered by dedicated power supply. Solar simulators are not only granting independence from external conditions, yet provide possibility of research expand due to tuneable output power and emissive spectrum. Over the years, solar simulators were powered by different types of lamps. Throughout the history, the solar simulators were used mainly in photovoltaic and space research, crystal growth industry, and the material testing. For mentioned purposes, the total thermal output power of simulator was playing secondary role in comparison to urgent need of spectral match, irradiance distribution and beam uniformity with terrestrial or extra-terrestrial sunlight. For thermal applications, solar simulators are facing the challenge of providing high output power, described by high radiant heat flux and high heat flux density over the specified target area. In presented paper the comparison of xenon arc, metal halide lams and tungsten halogen for thermal applications has been presented with emphasis on available thermal power, spectral match with natural sunlight and operational issues. The course of decision taken during the selection of artificial light source for construction of laboratory-scale solar pyrolytic reactor is proposed.

Open access
A Comparison of ETV and LA for the Determination of Trace Elements in Solid Samples by MIP OES

Abstract

The performance of electrothermal vaporization (ETV) and laser ablation (LA) of dry aerosols as sample introduction systems for microwave induced plasma optical emission spectrometry (MIP OES) are compared and evaluated in terms of detection limits, precision and accuracy for the determination of trace elements (Ca, Cd, Cu, Fe, Mg, Mn, Sr, Zn) in the same solid micro samples. In MIP OES both radiation sources can be independently adjusted to optimize the sampling process and then its subsequent excitation. A univariate approach and simplex optimization procedure were used to obtain the best signal/noise (S/N) ratio and derive analytical figures of merit. A comparison using a Student’s t-test between the results obtained by both ETV/LA-MIP OES methods for trace elements, and concentrations in standard reference material (SRM) and certified reference materials (CRMs) showed that there was no significant differences on a 95 % confidence level. The detection limits of the tested elements in solid samples by ETV/LA-MIP OES were in the range of 0.1 to 11 µg g−1 for all elements determined, while the corresponding absolute values in the range of ng. The precision of the results for ETV-MIP OES and LA-MIP OES varied between 2 and 4 % and 3 and 7 %, respectively. The linear dynamic ranges in the ETV/LA-MIP OES are extend over three decades of concentration. The methods were validated by the analysis of NIST SRM 2711Montana Soil, NRCC CRM PACS-2 Marine Sediment and NRCC CRM TORT-2 Lobster Hepatopancreas of different matrix composition and by the standard addition technique.

Open access
Designing a Pond and Evaluating its Impact Upon Storm-Water Quality and Flow: A Case Study in Rural Australia

Abstract

Storm-water management is a common concern in rural catchments where development-related growth causes increases of storm-water flows. Greater magnitude and frequency of storm-water create greater challenges for mitigating storm-water damage and improving water quality. The concept of Blue-Green Infrastructure (BGI) as a solution incorporates a wide range of applicable components with the aim of minimizing the effect of catchment development on flow regimes without changing the watershed morphology. BGI components manage storm-water by decreasing impermeable cover and expanding natural and semi-natural systems to store water or recharge and filter storm-water into the ground. In this paper, guidelines for designing a pond as a component of BGI are provided and, configuration and size of the pond are determined. Moreover, the impacts of the designed pond on storm-water peak flow and quality are assessed for the Tarwin catchment, State of Victoria, Australia. The results indicate that the introduction of the pond would have reduced outfall inflow by 94 % and would have achieved the reduction of 88.3, 75.5 and 50.7 % for total suspended solids, total phosphorus, and total nitrogen respectively, during the extreme weather event in June 2012.

Open access
Effect of Municipal Sewage Sludge on Soil Chemical Properties and Chemical Composition of Spring Wheat

Abstract

Municipal sewage sludge from rural sewage treatment plants is characterized by a substantial content of organic matter and macronutrients, which can be used in cultivation of cereals. In a farm located in the commune of Iwanowice in the south of Poland (Malopolska province), municipal sewage sludge was applied under spring wheat cultivation. The experiment was set up on heavy soil with slightly acid reaction and medium content of available forms of P, K, Mg. Application of sewage sludge in a dose of 23 Mg fresh matter per hectare (4.21 Mg d.m.) led to no significant changes in chemical properties of the soil. Application of sewage sludge significantly increased yield of spring wheat. That increase led to a significant decrease in the content of N, P, K, Na, Mg and Ca in spring wheat. Utilization of N, Mg, K, P and Ca from sewage sludge by spring wheat was at a level of 82, 63, 44, 36, 9 %, respectively, of the amount introduced with the waste. Application of municipal sewage sludge significantly decreased the value of Ca : P ratio in spring wheat grain and straw. The sewage sludge did not cause a significant change in the values of Ca : Mg, K : Na, K : (Ca+Mg), K : Mg and K : Ca ratios in spring wheat grain and straw. Municipal sewage sludge can be used environmentally, including for fertilization of cereals, provided that environmental standards are kept.

Open access
Identification of Degradation By-Products of Selected Pesticides During Oxidation and Chlorination Processes

Abstract

Advanced oxidation processes (AOPs) are considered to be one of the most effective methods for the decomposition of a wide range of hardly-biodegradable organic compounds, including pesticides. The implementation of such processes in the water streams treatment often leads to the formation of decomposition by-products of micropollutants occurring in water. These compounds, even in concentrations of a few ng/dm3, may negatively affect the water quality. Therefore, there is a need for detailed analyses that will allow to identify intermediates found in the AOP solutions and to assess their impact on the aquatic environment. The paper presents an attempt to identify by-products of three pesticides: triclosan, triallat and oxadiazon during ozonation, chlorination and UV irradiation of their water solutions. The identification of compounds was performed based on the results of the GC-MS analysis using the NIST v17 mass spectral library. It has been shown that during all of tested advanced oxidation processes, incomplete degradation of pesticides occurs. The number of micropollutant decomposition by-products increases with the increase of the applied ozone dose and UV exposure time. During the chlorination process Cl atoms were added to the tested compound molecules. In the case of triclosan, it led to the generation of compounds containing four or five chlorine atoms in their structure. The toxicological analysis performed by the use of the Microtox® and Lemna sp. Growth Inhibition Test showed the toxic nature of post-process solutions. The decomposition by-products of triclosan and triallate, generated during the UV irradiation process, were highly toxic against the test organisms (toxic effect > 75 %). This makes it impossible to drain these solutions into the natural environment.

Open access
The Impact of Hydrometeorological Events on the State of the Urban River Quality

Abstract

One of the aims of this paper was to study catchment and watercourse response to extreme events. The study area consisted of Orunski Stream in the northern Polish city of Gdansk. The study period (review of cartographic materials) covered the years 1908 to 2000, while field research covered the period from May 2009 to April 2010. In addition, measurements were performed to study the dynamics of changes occurring in the creek during rainfall events. Examination of the water chemistry changes made two days before heavy rainfall showed a significant increase in sulphates and nitrogen compounds. Additionally, pollutants washed from the basin contributed to a significant deterioration in the water colour. A rainfall of 1.3 mm caused an eleven-fold increase in stream flow, a twofold increase in the water level, and a fourfold increase in the velocity of water molecules. It might appear seem that such a small amount of rainfall would have no major effect on the hydrologic and hydrochemical parameters of a small creek. However, it is the maximum flow rate that is an important variable when assessing potential flood risk levels.

Open access
The Influence of the Filtration Bed type in the Pool Water Treatment System on Washings Quality

Abstract

This paper presents the influence of the type of filtration beds, used in swimming pool water treatment systems, on the quality and the possibility of reuse of washings. The research covered 4 pool cycles with sand, sand and anthracite, glass and diatomaceous beds. The degree of contamination of washings was assessed on the basis of physical, chemical and bacteriological tests. The possibility of washings drainage into the natural environment was considered, and the results of the research were compared with the permissible values of pollution indicators for wastewater discharged to water or ground. A direct management of washings from the analysed filters proved impossible mainly due to the high content of TSS (total suspended solids) and free chlorine. Washings were subjected to sedimentation and then the supernatant was stirred intensively. As a result of these processes, the quality of washings was significantly improved. This allowed planning to supplement the pool water installations with systems for washings management.

Open access
Is the Polish Smog a New Type of Smog?

Abstract

In recent years, every winter we face the problem of excessive air pollution in the cities in Poland. This phenomenon is usually called smog and is associated with the concept of acidic smog of London type. However, there is a fundamental difference between the Great Smog of London known from the literature and winter smog episodes in Poland. While in 1952 in London the smog occurred at low atmospheric pressure, in foggy and windless weather conditions, in Poland smog episodes occur most often at the influx of cold, high-pressure air masses from the east in sunny weather. There are also various harmful components of smog - in London it was dust (suspended particulate matter), sulfur dioxide and carbon monoxide, while in Poland it is suspended particulate matter and polyaromatic hydrocarbons, especially benzo(a)pyrene. A common factor is the inversion of temperature in the ground level of the atmosphere. The chemical composition of the “Polish smog” is analyzed in the study justifying the need to distinguish the two types of smog described.

Open access