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  • Environmental Management Research on the Berettyó River
    161-165
    Views:
    61

    Our department is involved in ongoing research into the hydrological and ecological interplay of the Berettyó River.
    In the first part of our study we classified the Hungarian section of the river from ecological and hydrological standpoints. We determined three typical parts of the river: a sandy and gravely bottom, a middle part with a sandy and muddy bottom, and a lower part, with muddy bottom. In theese sampling areas we measured and established the more important static and dynamic hydrological, physical and chemical characteristics.
    For the planned research we did a primary estimation of the environmental condition of theese sampling areas, on the basis of applicable biological and ecological indication methods.

  • 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.

  • Characterisation of basic water balance parameters of Debrecen
    35-40
    Views:
    166

    This work aims to develop a hydrological modelling tool to help managers make the right decisions for Debrecen, in the face of water scarcity and the increase in agricultural and domestic needs over time. The methodology was based on the creation of a climatic database, at monthly time steps, from 2016 to 2019, and cartographic (land use, digital elevation model, and hydrological network). As a next step, the watershed was delimitated into sub-basins to determine the shape and the physiographic characteristics of sub-watersheds. Finally, a hydrological study was prepared by calculating the time of concentration to build a database of water resources in the study area. This water resource will be used as an input parameter for urban farming.

  • Examination of the conditions of extreme water balance circumstances (water logging, drought) with environmental information technology tools
    79-86
    Views:
    185

    The Carpathian Basin is characterized by varying hydrological extremes, both in space and time. Hungary's natural endowments are more favourable than average, especially for agricultural production, with 5,3 million hectares of land we have which is suitable for agricultural production. These extreme water management are often occur in the same year and mostly in the same region, which may become more frequent in the future, especially in the lowland regions. The negative impacts of extreme water management was influenced by the land use changes in recent years, which has modified the runoff processes of the affected regions.

    The aim of the study was to research the formation of inland water and drought circumstances in two sample areas the Great Plain (Szolnok-Túri flat and Nyírség) by geoinformatic tools. During the investigation in the first step we determined that areas which are susceptible to inland water and drought, based on the AGROTOPO database. In addition, land-use categories of characteristics of the sample areas are evaluated according to the Corine Land Cover. Furthermore, after defining characteristic of NDVI values between the period of 2003–2013, we evaluated the effect of drought whether can be detected in crop failures in respective areas.

    Based on our results, we concluded that the formation of inland water and drought circumstances can be investigated in a large spatial extension by geoinformatic tools and databases.

  • The Effect of Changes in Forest Area on the Transcarpathian Tisza River Basin
    181-185
    Views:
    66

    Forests are unique global factors which ensure life for almost every living being on Earth. They play a major role in controlling water flows, preventing erosion and controlling the oxygen content of Earth’s atmosphere. By the end of the XXth century, it was realized that forests help to nature maintain and are vital parts of our natural environment. By the time societies realized this fact, economic and environmental effects had amplified which endanger forests. Due to their good water control and water protection abilities, and their function in climate control, mountain forests can provide a suitable environment for themselves, for their successful growth.
    Forests play a major role in soil protection, especially in mountain areas where they prevent soil erosion. By converting surface waters into subsurface waters, forests help with the accumulation of subsurface waters, which are the sources of springs, rivers and streams. In the summer, they protect the soil from drying out by creating a special microclimate. They positively affect the climate of surrounding territories.