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Open access

Ihor Kozak, Ivan Balaniuk, Diana Szelenko, Sergiy Balaniuk and Hanna Kozak

Abstract

The study was conducted within the actual area of Krempna commune in Jaslo county Podkarpackie voivodeship in Poland. Historical data and maps were analysed using the ArcGIS 10.3 program. The changes in the number of villages, householders and human population were presented. Religious composition for the year 1785 and ethnic composition for the year 1939 were evaluated. Only in the case of Ukrainian population, the Moran’s test has shown dispersed distribution (Index Moran’s for Ukrainians = −0.478664; Z = −1.684100; P = 0.092162). The total number of householders increased from 915 in the year 1785 to 1,409 householders in the year 1939 and decreased to 349 in the year 1965 and 333 in the year 2018. The traditional village system (TVS) of Krempna commune was depopulated after World War II. As a result, the agricultural abandonment and forest succession developed. Class area (CA) of settlements decreased from 1174.02 ha in the year 1939 to 248.13 ha in the year 1965 and 240.2 ha in the year 2018, and CA of forests increased from 7,268.20 ha in the year 1939 to 15,465.20 ha in the year 1965 and 15,841.3 ha in the year 2018. Villages that had begun the core of TVS together with tserkvas and chapels in the centre of village, roadside crosses and traditional private farms were lost. The scale and results of such changes are interesting for future research, mainly in terms of change in TVS infrastructure and culture.

Open access

Przemysław Stanisz, Jerzy Cetnar and Mikołaj Oettingen

Abstract

The highest efficiency in the usage of nuclear energy resources can be implemented in fast breeder reactors of generation IV. It is achieved thanks to the ability of consuming minor actinides (MAs) in energy production. One of the options to use this benefit is full recycling of MAs to close the nuclear fuel cycle. Monte Carlo burn up (MCB), an integrated burn-up calculation code, deals with the complexity of the burn-up process which is applied to the European Lead-cooled Fast Reactor (ELFR). MCB uses continuous energy representation of cross section and spatial effects of full core reactor model; however, it automatically calculates nuclide production in all possible reactions or decay channels. Multi-recycling of MAs can cause an intensified build-up of curium, berkelium and californium. Some of their isotopes are strong neutron emitters from spontaneous fission, which hinders fuel recycling. The implementation of a novel methodology for trajectory period folding allows us to trace the life cycle of crucial MAs from the beginning of the reactor life towards the state of adiabatic equilibrium. The result of the analysis performed is presented, showing the sources of strong contribution to the neutron production rate. The parametric sensitivity analysis method for selected nuclide reactions is applied, revealing sensitivity of transmutation chains for the production of neutron emitter isotopes.

Open access

Grażyna Przybytniak, Jarosław Sadło, Małgorzata Dąbrowska and Zbigniew Zimek

Abstract

Calf skin collagen and three amino acids essential for its structure, namely glycine, L-proline and 4-hydroxyl-L-proline, were irradiated with gamma rays up to a dose of 10 kGy. Conversion of radicals over time or after thermal annealing to selected temperatures was monitored by X-band electron paramagnetic resonance (EPR) spectroscopy. Some experimental spectra were compared with signals simulated based on literature data from the electron nuclear double resonance (ENDOR) studies. The following phenomena were confirmed in the tested amino acids: abstraction of hydrogen atom (glycine, proline, hydroxyproline, collagen), deamination (glycine, hydroxyproline), decarboxylation (hydroxyproline). Chain scission at glycine residues, radiation-induced decomposition of side groups and oxidative degradation were observed in irradiated collagen. The decay of radicals in collagen saturated with water occurred at lower temperatures than in macromolecules having only structural water. The paramagnetic centres were the most stable in an oxygen-free atmosphere (vacuum). Radical processes deteriorated the structure of collagen; hence, radiation sterilization of skin grafts requires careful pros and cons analysis.

Open access

Nadiia Yorkina, Olexander Zhukov and Olena Chromysheva

Abstract

The study of potential possibilities of mesofauna as bioindicator of soil contamination by heavy metals is one of the most important areas of urban ecology and soil biology. The work presents the results of ecotoxicological and bioindicative assessment of the environment and the biota of the Melitopol urbosystem of Ukraine. The dynamics of chemical properties of soils in different functional zones of the city is analysed. The complex indices of pollution of environmental components are determined. A bioindicative assessment of the ecological condition of the territory of the urbosystem on the indicators of vitality of the soil mesofauna is carried out. For the first time, regional species-bioindicators for the territory of the city of Melitopol were determined. The ecomorphic structure of soil mesofauna of various functional zones of the city was revealed.

Open access

Firoz Ahmad and Laxmi Goparaju

Abstract

Climate change and its severity play an important role in forest fire regime. Analysing the forest fires events becomes a prerequisite for safeguarding the forest from further damage. We have made an assessment of the long-term forest fire events at the district level in India and identified the forest fire hotspot districts. The spatial seasonal (January to June) district wise pattern and forest fire trend were analysed. In the second part of the study area (central part of India), we have evaluated the forest fire events in grid format with respect to the climatic/weather datasets, and the statistical analysis Cramer V coefficient (CVC) was performed to understand its association/relationship with forest fire events.

The study revealed that Karbi Anglong and North Cachar Hills districts of Assam of India have the highest forest fire percent among all districts equivalent to 3.4 and 3.2% respectively. Dantewada district of Chhattisgarh and Garhchiroli district of Maharashtra of India occupied 3rd and 4th rank with value 3.1 and 3.0% respectively. The grid-based evaluation (local scale) revealed that most of the fire equivalent of 80% was found in the month of March and April. Forest fire frequency of the month of April is spread over 88 % of the grids over the study area. The 11 years average seasonal month-wise (February to June) maximum temperature, wind velocity, relative humidity, and solar radiation were found in the range of (25.9 to 40.6), (1.69 to 2.7), (0.301 to 0.736) and (14.21 to 22.98) respectively. The percentage increase (in the month of March) of maximum temperature, wind velocity, and solar radiation were 36, 39 and 62% respectively, when compared with the preceding month; whereas, a 60% decrease to relative humidity that was observed in the same month is usually the major cause of forest fire events in the month of March onwards.

The evaluation of Cramer V coefficient (CVC) values of rainfall, relative humidity, potential evapotranspiration, maximum temperature, wind velocity, and solar radiation were in decreasing order and in the range of 0.778 to 0.293. The highest value of rainfall (0.778) showed its strongest association with the forest fire events. In the month of June, these areas receive adequate rainfall, which leads to an increase in the soil moisture and a reduction in forest fuel burning capacity by absorbing the moisture and it is a strong reason for less forest fire events during this month. Geospatial technology provides an opportunity to evaluate large datasets over various spatial and temporal scales and help in decision making/formulating various policies.

Open access

Bishnu Prasad Bhattarai

Abstract

Study of habitat segregation among the four species of cervids was conducted in the Chitwan National park of lowland Nepal. This study aimed to investigate the possible mechanisms of habitat partitioning among the four cervids - chital, sambar deer, hog deer and northern red muntjac using discriminant analysis and canonical correlation analysis. Present study considered four major niche dimensions - habitat, human disturbance, presence of predators and seasons. The data were collected by walking along the line transects that encompasses the different habitats, varying degree of human disturbances and frequency of predator’s presence. Results showed the significant effect of season on the habitat segregation among these cervids. There was higher niche overlap during summer season as compared to winter season. Habitat overlap between chital and muntjac was higher and unstable than others, which showed that they were the competitors of the same resources as enlightened by their generalist nature. Therefore, maintaining habitat heterogeneity and minimizing human disturbances will be better solutions for the coexistence of herbivores in the Chitwan National Park and can be an example for similar areas of lowland Nepal.

Open access

Viera Petlušová, Peter Petluš, Martin Zemko and Ľubomír Rybanský

Abstract

Intensification of landscape use brings along the negative effects on environmental components. These include surface water pollution. The aim was to determine the effect of landscape use on the water quality of the Žitava river. It was assumed that an area with the high proportion of anthropogenic activity would negatively affect water quality. At the same time, we assumed that an area with the lower proportion of anthropogenic use and with the higher proportion of natural and semi-natural elements contributes to self-cleaning ability of the watercourse. At the four observed sites, ammoniacal nitrogen (NH4-N), nitrate-nitrogen (NO3-N), phosphate-phosphorus (PO4-P) and water conductivity were monitored. Landscape use was analysed using the database of land cover based on the CORINE Land Cover methodology. Subsequently, it was observed how the landscape use affects the water quality. It was found that the very good state, represented by the Class I water quality, is according to the measured indicators mostly present in the areas predominantly covered by forests along with extensive use of elements of the agricultural land. The area with predominance of agricultural and urbanised sites where the anthropogenic influence prevails is characterised by average water quality. As the overall water quality of the Žitava river reaches the average, it is necessary to eliminate the pollution by constructing the sewer systems in the villages through which the watercourse is passing and, in agriculture, to ensure the adherence to the legislation concerning the protection of surface water against pollution from agricultural sources.

Open access

Hyam Nazmy Khalaf, Mostafa Y. A. Mostafa and Michael Zhukovsky

Abstract

Particle size distribution is an important factor governing whether aerosols can be deposited in various respiratory tract regions in humans. Recently, electronic cigarette (EC), as the alternative of tobacco cigarette, has become increasingly popular all over the world. However, emissions from ECs may contribute to both indoor and outdoor air pollution; moreover, comments about their safety remain controversial, and the number of users is increasing rapidly. In this investigation, aerosols were generated from ECs and studied in the indoor air and in a chamber under controlled conditions of radon concentration. The generated aerosols were characterized in terms of particle number concentrations, size, and activity distributions by using aerosol diffusion spectrometer (ADS), diffusion battery, and cascade impactor. The range of ADS assessment was from 10−3 μm to 10 μm. The number concentration of the injected aerosol particles was between 40 000 and 100 000 particles/cm3. The distribution of these particles was the most within the ultrafine particle size range (0–0.2 μm), and the other particle were in the size range from 0.3 μm to 1 μm. The surface area distribution and the mass size distribution are presented and compared with bimodal distribution. In the radon chamber, all distributions were clearly bimodal, as the free radon decay product was approximately 1 nm in diameter, with a fraction of ~0.7 for a clean chamber (without any additional source of aerosols). The attached fraction with the aerosol particles from the ECs had a size not exceeding 1.0 μm.

Open access

Andrea Diviaková, Dušan Kočický and Eliška Belaňová

Abstract

This paper deals with the application of ecological proposals within the land consolidation project process in Slovakia. Ecological proposals form part of the Local Territorial System of the Ecological Stability project, which is a compulsory material for developing land consolidation projects. The Local Territorial System of Ecological Stability for the cadastral unit of Kocurany village was worked out in 2013. Within the area, 31 localities were selected for the implementation of ecological proposals with a total area of 154.34 ha, namely 3 biocorridors, 2 biocentres, 9 interacting elements, 8 ecostabilising elements and 9 localities with the need of anti-erosion soil cultivation, or delimitation to permanent grasslands. The main task was to analyse the rate of acceptance of the proposed measures. It was found that only 20 localities with a total area of 119.37 ha were accepted into the land consolidation project. In order to improve all the landscape functions, the integration of quality ecological proposals from the Territorial System of Ecological Stability into the land consolidation projects is necessary.