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Abstract

The paper presents results of the measurements of the tropospheric ozone (O3) concentration and meteorological parameters: temperature, air pressure, relative humidity, speed and wind direction. The data were collected from January 2016 to December 2016 at station located in locality Centre (Banja Luka), Republic of Srpska, Bosnia and Herzegovina. Ozone is one of the most harmful pollutants to plants and health and highly reactive secondary pollutant. The present study covers investigation of the relationship between the concentration of ozone and meteorological parameters as well as time variations of ozone concentration (by hours, months, seasons). This topic has not been studied up to now in this region, although the recent research data indicates that there is a correlation between them and previously obtained from the world’s relevant scientific centres, as already cited above. Statistical analysis confirms string of rolls, which shows directional connection between tropospheric ozone and meteorological parameters, specially temperature (r = 0.148), air pressure (r = –0.292) and relative humidity (r = –0.292). These parameters are the most important meteorological factors influencing the variation in ozone levels during the research. The correlation ozone concentrations with speed and direction of wind is not significant, like other parameters.

Abstract

As a result of the activity of industrial enterprises, atmospheric air is being contaminated by gaseous pollutants. Such substances as chlorine and hydrogen chloride are considered to be harmful for both humans and plants. Vegetation is a universal filter that is able to combat the environmental pollution by industrial emissions with the help of appropriate technical facilities. The aim of this study is to analyze the level of accumulation of chlorine in the leaves of woody plants that grow in the area of forest plantations of sanitary protection zones of industrial enterprises. The objects of the study were the species of woody plants in the area of protective plantations of a number of enterprises in Zaporizhzhya: ZTMC, ZALК, ZABR, Zaporizhstal, Zaporizhzhya Ferroalloy Plant, Zaporizhvohnetryv, Ukrgrafit and Zaporizhtransformator. We established that during the vegetation period, a gradual accumulation of the element was the most intense in mature leaves, whose growth had already ceased. The maximum amount of chlorine was found at the end of the vegetation period. The concentration of the pollutant in leaves of woody plants in the area of sanitary protection zones of industrial enterprises is linearly proportional to the level of emissions of the pollutant into the atmosphere by a given enterprise. The largest coefficient of relative accumulation of chlorine in the leaves of such plants as Catalpa bignonioides, Acer negundo, Robinia pseudoacacia, Juglans regia, Populus alba, which can be used as information sites for the purpose of bioindication of atmospheric air pollution with chlorides, was established.

Abstract

In the submitted paper, we have analysed the results of a systematic survey of grassland communities, performed in Hodrušská hornatina highland, in Štiavnické vrchy mountains. The main aims of the research were: i) syntaxonomical classification of grassland vegetation; ii) analysis of the main ecological gradients in species composition; iii) evaluation of the influence of environmental factors on species composition of grasslands. The dataset included 153 phytosociological relevés recorded on grasslands. Grassland communities were classified within five associations: Holcetum lanati, Pastinaco sativae-Arrhenatheretum elatioris, Alchemillo-Arrhenatheretum elatioris, Anthoxantho odorati-Agrostietum tenuis, Onobrychido viciifoliae-Brometum erecti; and the successional and transitional stages belonging to alliances Arrhenatherion elatioris and Bromion erecti. The results of the Detrended Correspondence Analysis support our assumption that the main environmental gradient in species composition on grassland is related to moisture. The results of the Redundancy Analysis show that all used environmental variables explained 3.4% of the variability of the species data. The most important factors affecting the species composition were altitude, slope, distance from settlements, and management.

Abstract

The aim of the study was to determine the effect of electromagnetic fields and their shielding on the growth of dwarf runner bean Phaseolus coccineus L. Three sectors were separated on the device emitting electromagnetic fields: “E” - sector emitting electromagnetic radiation with the predominance of the electrical component, “EM” - sector emitting electromagnetic radiation without domination of its components and “M” - sector with a predominance of magnetic component. Fields generated by the device were also shielded with ADR TEX, a screen based on a nanocomposite in which the electric component of the electromagnetic radiation is absorbed by water dispersed within a dielectric matrix in various ways. The composites exhibit high dielectric absorption and shield electric fields within the frequency range from ~100 mHz to ~100 kHz. Electromagnetic fields with the predominance of the electrical component and without domination of its components delayed the initial emergence of runner bean seedlings. Shielding of electromagnetic field without domination of its components with ADR TEX screen protected against this negative impact on the emergence rate of young runner bean seedlings. Exposure of plants to differentiated electromagnetic fields adversely affected their growth. Plants exposed to electromagnetic radiation without domination of its components had the lowest height and the shortest internodes. Shielding of electromagnetic fields with ADR TEX screen efficiently protected against their negative impact on the plant growth. Electromagnetic fields and their shielding did not influence the size of leaves and the index leaf greenness (SPAD).

Abstract

This study shows the impact of the reforestation program by some tree species (Pinus halepensis, Cupressus sempervirens and Eucalyptus camaldulensis) on the soil physicochemical parameters in south-western Algeria steppe. The study was realized on soil samples from the Touadjeur site. One hundred soil samples were taken from the field, followed by physicochemical analyses in the laboratory. A comparison of the soil elements between reforested and unreforested sites considered as a control was carried out. The results show that there are differences in the physicochemical parameters of the soil between the reforestation and the non-reforestation ones constituted by a steppe vegetation. The ANOVA one way test shows a highly significant difference change in soil physical parameters, moisture, holding capacity and saturated hydraulic conductivity, but no change in apparent density, actual density and color. Also, from a chemical point of view, the differences concern the organic matter, organic carbon, pH and certain soil contents. The main differences in soil properties between the reforestation sites and the control site, reflect the consequences of forest management adopted by the forest services, most probably the choice of reforestation species.

Abstract

In the recent years photovoltaic (PV) industry has experienced a major growth, caused by the ever present annual decrease in module production prices and the expanding awareness of the general public in terms of renewable energy. There are numerous ways to implement PV modules as an additional energy source for a building, be it mounted on the rooftop, or building integrated (BIPV). An analysis of BIPV consisting of 8 modules with the power of 250 Wp each was carried out for the building of the Chemistry Faculty of Gdansk University of Technology (GUT). It included monthly irradiance and energy generation values and compared them to data obtained by the means of PV-GIS system, after inserting site specific coordinates. Additional research on the same type of a single module with the power of 270 Wp was conducted to provide more insight in this matter. A comprehensible analysis allows for defining a final conclusion for the decrease in energy yield for GUT BIPV installation. Data outputs are lower than expected based on PV-GIS values, as for the most time the facade mounted PV system experiences partial soft shading from the nearby park. Furthermore, it is not located directly facing south, but rather south-east which does not prompt ideal working conditions.

Abstract

The landscape of south-western Slovakia is characterised by anthropogenous reshaping, while fragments of undisturbed, waterlogged habitats have been preserved in what remains of the meandering ancient Žitava River. These refuges are inhabited by various small mammal species and their blood-sucking ectoparasites. Between 2014 and 2018, research on them was carried out in Slovakia’s Danubian Lowland (Podunajská nížina) during three out of the four seasons (spring, summer and autumn). The small mammals were captured at 27 localities. The occurrence of nine flee species from the Hystrichopsyllidae, Ctenophthalmidae and Ceratophyllidae families was documented on 12 small burrowing mammals. During the course of all the seasons in which research was conducted, Ctenophthalmus agyrtes, C. assimilis, Megabothris turbidus a Nosopsyllus fasciatus were found, among the most dominant species to be seen on small burrowing mammals.

Abstract

An ecosystem engineer is a species that indirectly changes the availability of resources for other organisms via physical modification of the habitat. A good example of such species is Ardea cinerea L. – a big waterbird that forms colonies up to a few hundreds of nests during the breeding season. The colonies modify the habitat in the close vicinity of the nests mainly through heavy input of organic matter (feces, dropped or regurgitated food leftovers, eggshells, dead birds, etc.), which in turn affects vegetation. In our previous study, we observed that the probability of occurrence of non-forest species under the nests was 29.5 times higher in control plots in two types of forest vegetation (oligotrophic pine forest and riparian mixed forest). Adaptation for long-distance dispersal turned out to be insignificant for the probability of species occurrence, which suggested that the diaspores of those species must have been present in the forest soil before the establishment of the grey heron colony. In the present study, we used the seedling emergence method to compare the structure of the soil seed bank in breeding sites and control plots in two forest ecosystems mentioned above. We also tested whether the increased amount of nitrates in soil had a positive effect on the rate of germination and growth of seedlings. The results have shown that some reservoir of ruderal species was indeed present in the control plots, although their amount was higher under the heronries. We have proved that the number of germinating seeds of ruderal species depends on the concentration of nitrate in the soil of the pine forest. Comparison of the dry weight of 30- and 60-day-old seedlings of Rumex acetosella (pine forest) and Betula pendula (riparian forest) from the control and breeding sites showed an increased size of seedlings coming from the breeding sites of both forest communities.

Abstract

Climate changes as well as the urbanisation and economic development influence the characteristics of the stormwater runoff in the cities. The sealing of drainage basin surface leads to an increase of the runoff intensity, thereby decreasing the rainwater infiltration. This situation can lead to the risk of flooding in urban areas. Therefore, especially in great cities there is a need for application of such solutions that will support the operation of the sewage systems. The examples of such solutions are, among others, the green roofs. The paper presents the results of investigation of the water retention capacity of 4 green roof models containing following growing media: (1) the typical green roof substrate without any amendments, (2) the substrate with addition of about 1 % by weight of hydrogel (the cross-linked potassium polyacrylate), (3) the substrate containing about 0.25 % by weight of hydrogel, (4) the substrate with addition of expanded clay and perlite. The models were not vegetated in order to investigate only the water retention capacity of drainage elements and substrates. The water retention capacity of green roof models was investigated in the laboratory conditions with use of artificial precipitations simulated after diverse antecedent dry weather periods (ADWP) amounting to: 1, 2, 5, 7, and 12 days. The intensities of artificial precipitations were relatively high and ranged from 1.14 to 1.27 mm/min, whereas their durations ranged from 7.75 to 12.56 min. These values of intensities and durations corresponded to the design rainfall intensities calculated using Blaszczyk’s equation for annual rain depth equal to 600 mm and the return periods ranged from 5 to 15 years. The obtained results indicate that the water retention capacity of green roof models, expressed as the volumes (or depths) of rainwater retained within their structures, increases with an increase of ADWP. Results indicate that the relation between ADWP and the amount of water retained in the layers of green roofs in the case of relatively short antecedent dry weather periods provided for the analysis (from 1 to 7 days) may be approximately linear. The results of the one-way ANOVA indicate that in the case of all models there is a statistically significant difference between the values of retention depth for specified ADWP (p < 0.001). During more than half of simulated precipitations, especially in the case of longer ADWPs lasting 5, 7, and 12 days the best water retention capacity had Model 3, with substrate containing about 0.25 % by weight of hydrogel. On the other hand, the results show that the weakest retention capacity had Model 2 (with substrate containing 1 % by weight of hydrogel). In the case of longer ADWPs (lasting 7 and 12 days) relatively weak water retention capacity had Model 4 (with substrate containing the addition of expanded clay and perlite). It can be concluded that too large amount of hydrogel added to the substrate can have an unfavourable impact on the water retention capacity of green roofs.

Abstract

The paper presents the results of modelling airflow for ventilation of a single-family house with an area of 180 m2. The building was equipped with mechanical ventilation with the possibility of varying the airflow. The airflow was calculated as a function of carbon dioxide concentration. The presence of people in selected rooms was an internal source of carbon dioxide. In order to properly design of a ventilation system and then model the contamination level, ContamW software was used. The year-long cost analysis was carried out for the installation working with variable airflow (day, night). The analysis took into account the price of the electricity used by the fans of Air Handling Unit and meteorological data to estimate the power input to the heater of the Unit. Different scenarios of system operation were included as an input data in order to find a difference in energy consumption. The calculations were to answer the question of whether it is necessary to apply expensive and advanced system that enables individual control of the airflow in every room or use the simple control of the central unit to vary the airflow in the ventilation system of single-family houses. The difference in operating cost between the system that maintains 800 and 600 ppm reaches 100 % and demonstrates the need of simple demand controlled ventilation system.