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Abstract

The role of mycorrhizal fungi has special importance in the case of low soil moisture because the colonization of vine roots by mycorrhiza increases water and nutrient uptake and thus aids the avoidance of biotic and abiotic stresses of grape. Our aim was to investigate in the Eger wine region the changes of mycorrhizal colonization, water potential, and yield quality and quantity of grape roots at three altitudes, along a changing soil moist gradient. Our results show that the degree of mycorrhizal colonization is higher in drier areas, which supports the water and nutrient uptake of the host plant.

Abstract

The application of biochars to improve soils and to mitigate global climate change is a popular research area all over the world, although it is not a new topic. In our study, wood chips char (BC) and animal bone char (ABC) were applied. The pot experiments were conducted under laboratory conditions. 2 grams of rye-grass (Lolium perenne) were seeded into each pot. The following various soil parameters were measured: pH (KCl), AL-P2O5, AL-K2O, total water soluble salt content and organic matter content. The measured parameters from the plant samples were: total-P, total-K and micronutrients. Results show that the negative or positive effect of pyrolysis solids cannot be determined clearly, further experiments are needed.

Abstract

After its establishment, the roof cadastre - solar cadastre I wish to introduce in this article will form a database, with the help of which we will be able to analyse solar radiation factors on the local level (street, house), and a map display will also be available. Through the implementation of the appropriate methods, we can establish roof/solar cadastres on the settlement/district/regional level and these can help to increase the rate of utilization of renewable energy sources.

Abstract

Organic matter input into soils is essential regarding agricultural, environmental and soil science aspects as well. However, the application of the pyrolysed forms of biochars and materials with different organic matter content gained more attention in order to decrease the emission of the green house gases (CO2, N2O) from the soil. During pyrolysis, the materials containing high organic matter (biomass-originated organic matter) are heated in oxygen-free (or limited amount of oxygen) environment. As a result, the solid phase, which remains after eliminating the gases and liquid phase, is more stable compared to the original product, it cannot be mineralized easily in the soil and its utilization is more beneficial in terms of climatic aspects. Furthermore, it can improve soil structure and it can retain soil moisture and cations in the topsoil for long periods of time, which is very important for plants. In our experiment, the effects of biochar and bone char were examined on soils by zinc adsorption experiments. Based on our experiments, we concluded that the pyrolysis products can have significant Zn adsorption capacity compared to the soil. Bone ash can adsorb more Zn than the charcoal product. The Zn adsorption capacity of soils treated by pyrolysis products can be described by Langmuir adsorption isotherms. However, based on the amount of pyrolysis products, one or two term Langmuir isotherm fits well on the experiment data, which depends on the time the pyrolysis product has spent in the soil.

Abstract

The Industrial Revolution had a negative impact on both the city and the environment. By the second half of the 19th century, the urban erosion of industrial cities cried for direct intervention and curing. The methods developed either along an urban or an anti-urban philosophy: they resulted in the new models of green belt systems aimed at solving all the main urban problems with restructuring the urban fabric, controlling the urban spread into the rural landscape, the lack of green areas and open spaces for recreation and social life, and the lack of green spaces for ventilation. Nowadays, the major cities and capitals around the globe are competing for titles such as healthier, more liveable or even greener city. Given the unfortunate attributes of the urban structure in the historical cities, the development of new transportation sites or green areas is an extremely difficult issue. On the other hand, in the big cities, the brownfield sites are considered as reserve areas for sustainable urban development. Reusing the brownfields and rust areas is already a land saving urban development approach and in case of a complex and ecological urban rehabilitation it can underlie the development of an efficient urban green system and green network.

Abstract

The effect of populin extract from black poplar (Populus nigra) on late blight was assessed under laboratory and field conditions. The growth rate of hyphae was found to be significantly lower after 1v/v% populin application, and no hyphae growth was detected under 3 and 6v/v% populin application. Populin also reduced the light blight severity on potato leaves under field conditions. From our results, we have concluded that populin extract can be considered as a new and environmentally-friendly alternative for the control of late blight under field conditions.

Abstract

This article presents and summarizes our observations based on historical research and site visits of 130 dendrological gardens in Hungary and 36 sites in Transylvania. The results favourably demonstrate the outstanding ecological and landscape values of these dendrological gardens in the Carpathian Basin. The research identifies the most typical exotic woody species that can be still found in those dendrological gardens that were developed in the Carpathian Basin during the era of creating landscape gardens, which is the 19th century in our region. We have defined about twenty exotic tree species, located in the researched dendrological gardens, of which presence highly affects the architectural and botanical composition, just as the landscape appearance or atmosphere of these gardens. Beyond all these effects, the article also highlights two other important points of the dendrological gardens: firstly, these gardens were breeding and acclimatization centres for spreading the new woody species, while, on the other hand, representatives of the spontaneous flora remained as veteran trees in these protected gardens, representing - mainly due to their age - outstanding ecological, dendrological and cultural values.

Abstract

We have monitored the behaviour of different polyethylene foils including virgin medium density polyethylene (MDPE), MDPE containing pro-oxydative additives (238, 242) and MDPE with pro-oxydative additives and thermoplastic starch (297) in the soil for a period of one year. A foil based on a blend of polyester and polylactic acid (BASF Ecovio) served as degradable control. The experiment was carried out by weekly measurements of conductivity and capacity of the soil, since the setup was analogous to a condenser, of which the insulating layer was the foil itself. The twelve replications allowed monthly sampling; the specimen taken out from the soil each month were tested visually for thickness, mechanical properties, morphological and structural changes, and molecular mass. Based on the obtained capacity values, we found that among the polyethylene foils, the one that contained thermoplastic starch extenuated the most. This foil had the greatest decrease in tensile strength and elongation at break due to the presence of thermoplastic starch. The starch can completely degrade in the soil; thus, the foil had cracks and pores. The polyethylene foils that contained pro-oxydant additives showed smaller external change compared to the virgin foil, since there was no available UV radiation and oxygen for their degradation. The smallest change occurred in the virgin polyethylene foil. Among the five examined samples, the commercially available BASF foil showed the largest extenuation and external change, and it deteriorated the most in the soil.

The Journal of Sapientia Hungarian University of Transylvania

Abstract

The World Health Organization has estimated that more than 80% of the world’s population in developing countries depends primarily on herbal medicine for basic healthcare needs. Approximately two thirds of the 50 000 different medicinal plant species in use are collected from the wild and only 10% of medicinal species used commercially are cultivated. DNA-based molecular markers have utility in the fields like taxonomy, physiology, embryology, genetics, etc. DNA-based techniques have been widely used for authentication of plant species of medicinal importance. The geographical conditions affect the active constituents of the medicinal plant and hence their activity profiles. Many researchers have studied geographical variation at the genetic level. Estimates of genetic diversity are also important in designing crop improvement programmes for the management of germplasm and evolving conservation strategies. The DNA-based molecular marker helps in the improvement of medicinal plant species. DNA markers are more reliable because the genetic information is unique for each species and is independent of age, physiological conditions and environmental factors.