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  • Relation of availability and barley uptake of some potentially toxic elements
    7-10
    Views:
    70

    A small-plot microelement load field trial was set up on brown forest clay soil with eight elements (Al, As, Cd, Cr, Cu, Hg, Pb, Zn), on 3 levels each (0/30, 90, 270 kg element ha-1). The soil was treated with soluble salts of elements once at initiation (1994). In the seventh year of the experiment (2001) winter barley was the test plant. The total element content was determined in plant samples (shoot, straw, grain) after microwave digestion using cc.HNO3+cc.H2O2. The element composition of the prepared samples was determined using ICP-MS technique. In the experiment toxic effects of treatments and yield loss could not be observed. Zn and As contents in barely shoots were only moderately increased by increasing microelement loads. Effects of Cr, Cu, Hg, Pb and Al treatments could not be observed. On the other hand, Cd accumulation was significant in the shoot. Cd content was also increased both in straw and grain. Results of this experiment prove that Cd remains mobile in the soil-plant system for a long time. Its accumulation can be observed both in vegetative and reproductive parts of plants without toxic symptoms and yield loss.

  • Price Risk Management by Futures Markets and Public Warehousing
    58-65
    Views:
    81

    The principal achievement of this paper is the combinative use of two market institutions: public warehousing and commodity exchange and how their joint application is beneficial for the players on the grain market. Based on a theoretical foundation, a calculation model was developed in order to assist short and long-term marketing decisions. It allows all the three participants of the market: producers, consumers and traders, to use this model in order to establish their own business strategy. The model can be used to analyse factors influencing the establishment of price; therefore, it can be also used for policy-making decisions.

  • The use of biogas in energetics
    41-46
    Views:
    102

    In our study we examine the technical facilities of biogas production in the economic environment of a given region. The region can be considered as typical: it has animal farms, a poultry-processing plant with the characteristic problems of environment load and by-product handling. Biogas can be used for energetic purposes, and, in large scale, it can be sold as electric energy. The heat coming from the engine and the generator can be collected in heat exchangers and can be used for preparing hot water and for heating. One third of the gained energy is electric, two thirds are heat. The aim of the local owner and the economic management is to increase the rate of cost-effectiveness in general. We examined the tecnnical and economic conditions of establishing a biogas plant (using data of an existing pigfarm). We planned the biogas plant and calculated the expected investment and operational costs and return.