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  • Energy crops on less favoured (alkaline) soil
    115-118
    Views:
    127

    The reduction in fossil energy and row material sources induces growing demand for renewable resources. The growing demand for herbal raw materials has land use impacts as well. One way to reduce the conflict between the food and energy crops can be the utilization of less favored areas by growing energy crops. Among the potentially available areas for this purpose the salt affected soils (SAS) occupy a significant territories. SAS with structural B-horizon (meadow solonetz soils) represent the most wide spread group of SAS in Hungary. About half of these soils have been reclaimed and used as arable land and the remaining 50% are used as grassland. Sweet sorghum production for manufacturing of alcohol production was investigated in a long term amelioration and fertilization experiment on a salt affected soil (meadow solonetz). By means of regression analyzes the effect of sodium content of the soil and increasing mineral fertilizer doses were studied. According to the multiple regression analysis only the effect of nitrogen fertilizer was significant. On the solonetz type salt affected soil the effect of water soluble salt content of the soil was not significant, but there was a closer correlation between the ammonium-lactate sodium content and the yield of sweet sorghum. The maximum green mass was 45–50 t ha-1, in the case of low Na content and high level of nitrogen fertilization.

    In order to quantify the potential yield of natural grass vegetation the relationship between the soil forming processes and the grass vegetation
    was investigated. Beyond the different forms of Na-accumulation, the spatial pattern (mosaic-like characteristic) is also an inseparable feature of salt affected soils. The difference in the water regime, caused by the micro-relief is the main cause of variability. The run-on water keeps the deeper parts of the catena position wet longer. The wet situation causes more intensive leaching. In the low-laying parts of salt affected soils species preferring wet situations (mainly Alopecurus pratensis) are in majority. On the higher parts of the micro-relief species tolerating dry situations (mainly Festuca  pseudovina) are dominant. The yearly grass production of low laying areas can be 4–7 t ha-1 but because of prolonged wet  conditions the grass is not grazed and mowing can only be in old state. This old grass is not proper for feeding, but it may be suitable as energy plant. 

  • Assessment of energy generated by biogas production in the educational industrial unit of the University of Szeged, Faculty of Agriculture, with special regard to biomass originating from agriculture and the food industry
    137-140
    Views:
    104

    The importance of waste treatment is increasing. Environmental aims are the main driving force. Stricter regulations for landfills lead to the development of alternative treatment methods for waste. For agro-mechanical research, wastes from animal rearing and the food industry, secondary-tertiary biomass, is of deep concern. Available technology is versatile and relatively simple to use as a reliable and effective means of producing a gaseous fuel from various organic waste. The most common application has been the digestion of animal dung, agricultural, and food-industrial waste. This was studied by our department in our pilot farm of our Faculty. The 50-dairy cow, family sized model farm was built in the summer of 1991, as a result of a Dutch – Hungarian cooperation, on the property of the Faculty. The new pig farm, with 30 sows, and the new goat farm, with 100 nannies, was given to the Faculty on 25 April 2001. On the basis of livestock data, the annual dung production and the producible energy were determinate. The energy was calculated by biogas production coefficients in literature.

  • Reduction possibilities of the production costs of green electricity by using waste heat
    15-20
    Views:
    200

    In my study, I examine the possibility of the reduction of green electric power’s gross production cost. My research topic may have wider considerations, since in the case of CHP technology the utilization of by-product thermal energy is not possible, and the whole production cost devolves upon green electric power. I introduce five options for the use of the heat energy, based on national and international literature and in-depth interviews.

    From the aspect of efficiency, it can be stated that as alternatives, beer production and desiccation may be mentioned, since these two models were appropriate for the utilization of the total quantity of waste heat, and in the given circumstances the lowest reduction of green electric power’s production costs was achieved in these cases utmost.

  • Alternatives of the multiple use of Virginia mallow (Sida hermaphrodita L. Rusby) as a shrub-replacing mallow in the temperate climate zone
    51-56
    Views:
    175

    In the seventies of the previous century, Dr. Zoltán Kováts set two directions in the research of mallows. One of the directions was the biotechnology of the mallow species and the other direction is using the mallow species as biomass material. In order to do this he brought mallow mother spawns of ornamental and biomass sorts from botanical gardens abroad and tested many of them, including the a Sida hermaphrodita kind. Fourty years later, for the second time this plant, known as the „energy mallow” got back to Hungary again, right into the sight of hungarian biomass business with the help of László Balogh and his associates using help from Poland. This genus got into the center of our research, because of it’s valuable attributes. The latest experiments are about using it as an energy plant, without examining genetic details. The plant grows up to more
    than 3 meters, has high growing rate and produces big amount of green mass. We don’t have any hungarian data about whether the plant continues the sufficient growing rate or not, after cutting it back.
    We have to explore the potentials in the Sida’s sublimation. The plant is mostly suitable for ornamental and energy utilization, so further sublimation should be aiming for these aspects. During my research period, we are willing to get to know these potentials and the best possible use of them.

  • Competitiveness of the biomethane opposite with the CHP technology of biogas by definite plant size
    5-9
    Views:
    132

    The biogas sector has never before aroused so much attention as it does today. Combined heat and power (CHP) reliable and cost-effective technologies that are already making an important contribution to meeting global heat and electricity demand. Due to enhanced energy supply efficiency and utilisation of waste heat renewable energy resources, CHP, particularly together with district heating and cooling (DHC), is an important part of national and regional Green House Gas (GHG) emission reduction strategies.

    During my work I am going to use the basic data of a certain biogas plant than I assemble one model from that. Against the CHP technology I am going to plan a biogas cleaning-equipment. During my research it revealed, that in the case of a 1 MW output power plant it is not worthy to deal with biogas cleaning between national conditions. Investigating the quantity of heat recovery in the CHP technology it is obvious, that the net income at 1 m3 biogas is at least 72 times more than the cleaning technology (heat recovery is 0%).

  • Effect of soil-compost proportion on the abiotic and biotic parameters of soilplant system
    99-104
    Views:
    147

    The environmental awareness, coming to the front in the 21st century, motivates us to supply the plant nutrient demand (in point of the plant, the environment and the human health) with natural materials.
    Composting is known since the beginning of civilization. We came to know more the processes of composting as a result of last decades’ research, but numerous unexplained questions remained up to this day. The good compost is dark gray or brown, and it should not create an odor. It has aggregate structure, and it’s pH is neutral. Compost is soil-like (Fehér, 2001), nutrient-rich material, which contains valuable nutrients extracted from soil, so if we recycle this, we can decrease the chemical fertilizer and other (example: mineral energy) expenses.
    The reason of that we chose the more accurate cognition of compost utilization is to do more effective the site-specific nutrient supply. This increases the average yield and the quality of yield. Besides we can decrease the harmful effects, which endanger the plant, the environment, and the human body.
    During the compost utilization experiment we blended the  acid sandy soil with compost in 4 different volumetric proportions (5 treatments) than we set the pots randomized. The advantage of this method is that we can provide equal conditions for plants so we can measure the effect of  treatments correctly. Our experimental plant was ryegrass (Lolium perenne L.), that grows rapidly, tolerates the glasshouse conditions, and indicates the effect of treatments well. After the harvest of ryegrass we measured the fresh and dry weight of harvested leaves and the total C-, N-, S-content of the dry matter and of the soil, we examined the pH and the salt concentration of  soil as well. 
    Our aim was to study and evaluate the relations between the compost-soil proportion and the nutrient content of soil and plant. In our previous experiments we confirmed (based on variance analyses) that the compost has a beneficial effect on soil and increases the nutrient content of the soil (Szabó, 2009). But it’s important to appoint that the compound of compost is seasonally change: in winter the selective gathered municipal solid waste contains salt that were applied for non-skidding of roads, but salt has a negative effect to the plant. We proved that in our experiment the 25/75% compost/soil proportion was ideal for the plant. This content of compost effected 6 times higher green matter weight compared to the 100% sandy soil. 

  • Water managed properties of apple and pear trees based on lysimeters
    129-132
    Views:
    186

    A significant proportion of the aboveground green and dry weight of the plant is constituted by foliage. The canopy is an important factor of plant growth. On the one hand, the canopy absorbs solar energy, which is necessary for photosynthesis; on the other hand, it accumulates the nutrients absorbed by the roots, and most of the water-loss occurs through the foliage. The determination of the full canopy is not an easy target. In our research, we developed a measurement method to determine the leaf area. With the parameters of the examined tree (leaf length and maximum width) and the data of the ADC AM 100 leaf area scanner, we determined the k-value, with which we can easily and fast evaluate the leaf surface. Furthermore, we defined from the water balance of compensation lysimeters the cumulative transpiration of fruit trees and the efficiency of water use of trees. From the examined trees were made a 3D depiction, which show the shape, branching and the location of trees.

  • Calculating possibility of the leaf area index of apple and pear trees
    229-233
    Views:
    189

    A significant proportion of the aboveground green and dry weight of the plant constitutes the foliage. The canopy is an important factor of plant growth. On one hand the canopy absorbs the solar energy, which is necessary for the photosynthesis, on the other hand accumulates the absorbed nutrients by the roots, and the most of the water-loss happens through the foliages. The determination of the full canopy is not an easy target. In our research we developed a measurement method to determine the leaf area. With the parameters of the examined tree (leaf length and maximum width) and the data of ADC AM 100 leaf area scanner we determined the k-value, with which we can easily and fast evaluate the leaf surface.

  • Evaluation of water balance in apple and pear trees
    193-198
    Views:
    159

    A significant proportion of the aboveground green and dry weight of the plant constitutes the foliage. The canopy is an important factor
    of plant growth. On one hand the canopy absorbs the solar energy, which is necessary for the photosynthesis, on the other hand accumulates
    the absorbed nutrients by the roots, and the most of the water-loss happens through the foliages. The determination of the full canopy is not
    an easy target. In our research we developed a measurement method to determine the leaf area. With the parameters of the examined tree
    (leaf length and maximum width) and the data of ADC AM 100 leaf area scanner we determined the k-value, with which we can easily and
    fast evaluate the leaf surface. Furthermore we defined from the water balance of compensation lysimeters the cumulative transpiration of
    fruit trees and the efficiency of water use of trees.