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  • Conceptional Model of Regional Agricultural Water Management System
    199-209
    Views:
    91

    Our study focuses on the water management improvement of the Hajdúsági-löszhát (loess ridge). The Hajdúsági-löszhát (loess ridge) is an intensive agricultural area. At the same time, the problem of increasing water demand is still not solved, so towards of safety production irrigation should be improved. To realise this should be known not even agricultural water demands but industrial and urban ones as well, thus a complex water management system is required to be worked out.
    In the first part of the research, the water demand in the area is mapped, then a conceptional model of the Hajdúsági-löszhát’s (loess ridge’s) water management system is created. After collecting data the water management scenario is summarized in a real time model splitted into five periods.
    During the research, the instruments of spatial informatics (GIS) are used to get acquainted with the variation of the hydrological parameters in space and time. To understand and simulate the different decision making processes and to choose the right decision alternative, a decision support system is created with the use of spatial informatics data.
    In addition, considering the potentially right decision alternative, irrigation will be started in practice, an effect and after-effect inquiry will be made, and the results will be analysed, evaluated and summarized. Finally, a suggestion to the most adequate irrigation technology will be made.

  • Complex assessment of inland water fish stocks
    74-80
    Views:
    69

    In the domestic fish production, natural waters have yielded for several years about 7-8 thousand tons. This, from the point of view of outputs, considering the almost 130 thousand hectares of natural water, is rather low, it means approximately 55-60 kg/ha mixed fish.Although the various natural waters can differ significantly on the basis of yields, yet on the majority of the territories, the results were low. In the case of our extensive still waters and rivers, the reason can undoubtedly be found in the combined effect of the lack of the possibility of reproduction of the fish stock and the over-fishing. Fishery built on planning supposes the best possible knowledge in the given circum stances of the parameters of the water area and its fishstock. Lacking this knowledge, it is not possible to establish the optimal use fulness of the resources, what is more, the management can make faulty decisions – as a result of a lack of information -, which can risk the success of later activities.
    It is known that many factors have an impact on the success of the fishery, as well as some information in connection with the water area and the fish stock are necessary, the knowledge of which make it possible to manage the fishery in a planned way. One part of the information is available, while the other part is incomplete or not deep enough. The necessary data are dissimilar depending on their nature, can be obtained from different places, by different methods.
    As the first step for executing the field surveys and processing data, I developed a complex model, which contains in a unified system the steps of estimating the fishstock. I made the sampling on the basis of this. Part of the model is a fish faunistic survey, as well as a morphological survey of the water area. The information gained from these are important for making more accurate the system of devices of the samplings for stock estimation (duration, number of net-rows) and for assigning its place (places representing the best way the physical characteristics of the given water area). The major stages of stock-survey: A) faunistic survey, B) physical survey of the bed, and C) sampling with the help of gill-nets. This is followed by the evaluation by the computer module.
    The results of the research create a methodological and technical background for the fish faunistic and population biologic surveys still performed in different ways in our country, and by applying these methods together, all basic information about natural waters which help decision-making concerning fisheries can be obtaine deffectively.

  • The effect of the preparation method on the physical and chemical characteristics of propolis tinctures
    163-168
    Views:
    225

    The effect of the preparation method was examined with regards to the physical and chemical characteristics of the propolis tincture, namely the extraction time and the ethanol content of the extraction solvent to the dry matter, polyphenol, flavonoid, phosphorus, calcium and copper concentration, respectively. The dry matter, the polyphenol and the flavonoid content were the lowest in the water extract of the propolis; however, significant increase was noticed depending on the extraction time. Significantly higher concentrations were found in 50 V/V% tinctures. The highest dry matter and flavonoid contents were analysed in 100 V/V% tinctures, whereas highest polyphenol content was found in 80 V/V% tinctures. However, the differences were not significant in several cases between latter tinctures. Moreover, the increase was not determined in some cases depending on the extraction time. Phosphorus and calcium concentrations were decreased depending on the increasing ethanol content, whereas copper concentration was increased up to 80 V/V%. Higher increase was found in the case of 0 and 50 V/V% extracts than in 80 and 100 V/V% tinctures. Moreover, in latter cases, no significant differences were found on several occasions, depending on the extraction time. There was no connection between the flavonoids and the calcium as well as the phosphorus content, whereas flavonoids may be made complex with copper. However, the amount of the possible complex was negligible.

  • Application of hydrological models for agri-environmental management based on international and national experiences
    45-50
    Views:
    115

    The ecological restoration of surface water flows requires the use of complex GIS and hydrological models. The HEC -RAS and MIKE11 programs calculate the hydraulic characteristics of runoff using the geometry and bed resistance the of flows. The presentation of some possible applications made through an example of the Berettyó, which is an extremely regulated river. The river belongs to the meandering category by Parker's classification system, which uses the relationship of the slope-Froude number and the depth- width ratio. Three coefficient of the four determining factor (entrenchment ratio, slope of water level, width-depth ratio) also indicates a mediocre to high sinuosity, while the river regulations established nearly straight bed-line. The standard water flow rates and characteristics have been determined based on the modeled Froude and Reynolds numbers. The flow conditions shifted to the laminar type by the changed line drawing which is ecologically lower status. Based on the results the morphological and ecohydrological river rehabilitation is appropriate.

  • Influence of Hydrological Parameters on the Biodiversity of the BerettyóRiver I.
    215-229
    Views:
    96

    The DIRECTIVE 2000/60/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL orders the measurement of the state of natural and artifical waters. We therefore applied environmental qualification methods, which allow inductions of the searched area in environmental management, conservation and water quality protection points of view. These methods are accepted in interdisciplinary sciences, and are in use in Hungarian and international practice. We applied the range data measured along the Berettyó River, and ratified by the remote sensing, to count hydrological-hydraulical attributes of the stream, by the framework of the Hec-Ras programme. We processed the physical, chemical and biochemical water qualifications, determined the MMCP-index (the point-system of the Hungarian macrozoobenthos taxons), and estimated the Spencer index-numbers, which were based on complex environmental qualification and bioindication. Appointed, that the different results of researches are not inconsistent. This results together the spatial analysis reveal the natural and anthroponetic specialities of the river and the landscape, which determine the environmental flavours and biodiversity. The bioindicators represent better environmental status, than the physical, chemical and biochemical parameters. The natural conservationist importance of drainage canal network of Bihari-Plain is appreciated by these facts.

  • Implementation alterantives of the CIVAQUA complex water management program in the Debrecen region
    71-73
    Views:
    117

    Hungary is one of the countries in Europe which has the largest amount of water supply because of its geographical conditions. Water comes from the surrounding mountains makes this water supply even more bigger. This precious water base needs to be treated responsibly and the most efficient way. The Civaqua program is a project with the above-mentioned conditions, made by the Local Government of Debrecen and the Water Directory of Trans-Tiszanian Region. This project deals with the exploitation of the East-Main Chanel’s water for social welfare, agricultural and inverimental protection purposes in Debrecen and its agglomeration. The aim of this paper is to give an overall insight into the investment plans of Civaqua program and it is also examines its positive direct and indirect effects on the region.

  • Element content analyses in the Institute for Food Sciences, Quality Assurance and Microbiology
    203-207
    Views:
    110

    The role of chemical elements to ensure and promote our health is undisputed. Some of them are essential for plants, animals and human, others can cause diseases. The major source of mineral constituents is food, drinking water has a minor contribution to it, so the knowledge of elemental intake through food is crucial and needs continuous monitoring and by this way it promotes the food quality assurance and dietetics.
    With the evolution of spectroscopic methods increasingly lower concentrations could be determined, so the elemental composition of a sample could be more precisely and fully described. Due to the results the gathered knowledge up to the present is supported and new observations can be done helping us to understand such complex systems as biological organisms are.
    The quality of a food is determined by the full process of its production, consequently it starts with agricultural production so elemental-analysis usually cover the whole soil – plant – (animal) – food chain, by this way the „Fork-to-Farm” precept is true in elemental analysis field also.
    The history of elemental analysis in the University of Debrecen, Centre for Agricultural and Applied Economic Sciences, Faculty of Agricultural and Food Sciences and Environmental Management, Institute of Food Processing, Quality Assurance and Microbiology goes back to 1980s when the so called Regional Measurement Central gave the background for research. The continuous deployment resulted in an obtain of an inductively coupled plasma atomic emission spectrometer (ICP-AES) in 1988, which extended the scope of examinations due to its excellent performance characteristics
    compared to flame atom absorption (FAAS) and flame emission spectrometers (FES). The instrumental park retain up to date correlate to the developing analytical techniques due to acquiring a newer ICPAES in 1998 and an inductively coupled plasma mass spectrometer in 2004 – which sensitivity is three order of magnitude better compared to ICP-AES. The Institute supports the work with its own ICP-AES and ICP-MS since 2011.