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  • Heavy Metals in Agricultural Soils
    85-89
    Views:
    178

    The soil constitutes the basis of the food chain. To keep soil conditions in a good trim is very important, it’s part of the sustainable development and of producing food supply harmless to health.
    In some cases, soil productivity is the only important part, qualitative requirements or economical characteristics can improve it. The soil is threatened by two danger factors: the soil degradation and the soil pollution. The accumulation of different harmful and/or toxic substances in the soil is well known. Heavy metals constitute a part of it. Metals in the soil and in the soil-solution are balanced. This balance depends on the type of the metal, on the pH, on the cation-band capacity of the soil, on the redox relations and the concentration of cations in the soil.
    To be able to handle the metal contamination of the soil, it is important to estimate the form, the possible extension and the concentration of metals.
    Of course, the different types of soils have different physical-chemical, biological and buffer capacity, they can moderate or reinforce the harmful effects of heavy metals. To draw general conclusion of the dispersion and quantitative relations on the metals originated from different contamination sources is hard, because in some emissive sources contamination is limited in small areas but on a high level, some others usually expand on larger areas, and as a result of equal dispersion, the contamination’s level is lower.
    Heavy metals – unlike alkali ions – strongly bond to organic materials, or infiltrate in a kelát form. Their outstanding characteristic is the tendency to create metal-complex forms. Kelats take part in the uptaking and transportation of heavy metals. Heavy metals exert their effects mostly as enzyme-activators.
    The metals cannot degrade in an organic way, they accumulate in living organisms, and they can form toxic compounds through biochemical reactions.
    Lot of the heavy metals accumulate on the boundaries of the abiotic systems (air/soil, water/sediment), when physical or chemical parameters change, and this influences their remobilization.
    Human activity plays a great part in heavy metal mobilization, results in the human origin of most biochemical process of metals.
    To understand the toxic influence of accumulated metals of high concentration, their transportation from soils to plants or their damage in human health, must clearly defined and investigated.
    For effective protection against soil pollution, the types and levels of harmful pollution to soil must identified, regarding legal, technical and soil-science aspects, preferable in a single way. Difficulties in this area mean that toxicity depends on loading, uptake, soil characteristics and living organisms (species, age, condition etc.), furthermore, local and economic conditions considerably differ.

  • Causes of floods and flood protection in Subcarpathia
    72-75
    Views:
    188

    Subcarpathia is one of the richest regions in surface waters in the Ukraine. Due to its geographical, relief and climatic conditions, it belongs to the active precipitation zone, where great floods frequently occur. As a result of many years of observation, it can be concluded that the interactions of many natural factors can lead to various floods in the catchment area of the river Tisza. These are mostly hydro-meteorological factors, which can lead to great floods with the characteristics of the formed flow. Human activity also significantly influences the occurance of floods: clearing, which can accelerate the process of the runoff, ploughing in the catchment area, which can lead to erosion and the utilisation of areas endangered by floods for various economic sectors.
    A series of questions arose in recent years regarding the formation of floods: what could be the causes of floods and what actions need to be made to prevent them. The evaluation of floods made us conclude that passive protection by using dams does not always ensure protection against floods as these were constructed in different times for different water levels. Many factors can affect the whole process which cannot be foreseen, therefore the development of new solutions and new technologies is necessary in flood protection.

  • A study of social and economic influences of universities in the Derecske-Létavértes subregion
    153-157
    Views:
    211

    Businesses operating in the region – adopting to local conditions – mostly pursue agricultural activities. Their R+D activity is rather moderate and largely focuses on development, moreover, the range of innovative businesses is relatively significant, which businesses – before long – will become potential partners for institutions of higher education (especially for Debrecen University).

    Social impacts of universities are notable on the person’s status in the labour market. Our study of the Derecske-Létavértes region shows that those with a university degree have an advantageous position in the labour market, compared to the sample of youth aged between 16 and 35. Knowledge obtained at college and other skills greatly help the young to find employment.

  • Bioreactor in the service of sustainable development
    111-118
    Views:
    372

    The control of our relationship with our environment is one of the greatest challenges of the 21st century. This has an effect on the economic and social processes and the human activities. All of these are included in a new developmental strategy: the strategy of sustainable development.
    The strategy of sustainable development prevails by the new technologies and it is realized on high-tech level as the fermentation manipulation of organic materials, biogas production and production of “green” electric current. 
    One of Europe’s largest bioreactors has been established in Nyírbátor in Hungary at first (chief executive: Mihály Petis).

  • The role of agriculture in regional development
    25-30
    Views:
    724

    Agriculture is the leading national economic sector of Hajdú-Bihar county. The proportion of employees in this sector and the share of pro ducts produced in this region is above the country average. The contribution of agriculture to the GDP is 6.3%, as opposed to the average value of the country (3.3%). Based on their primary activity, 8% of the enterprises in the county are classified as agricultural and forestry companies, while this proportion is only 5.3% in the whole country.

    Nearly three quarters (71.1%) of the sowing area is occupied by maize and other cereals, mainly wheat. This proportion is slightly more than the country average (69.2%). The proportional area of oil crops - including sunflower – and roughage is nearly the same as the country average. However, there is a significant difference in vegetable production. Due to the higher intensity of vegetable production, the area occupied by vegetables is three times the country average. 19.4% of the crop products, 23.5% of animal products and living animals, 25.8% of the income generated by production factors and 29.8% of net enterprise income of Hungary originates from the North Great Plain region.

    The facilitation of creating local markets, e.g. local public food supply, satisfying the needs of food trade with local goods, the necessary awareness raising actions, secondary and higher education of experts, as well as the more specific and targeted utilisation of development resources are agricultural development tasks.