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  • The Evaluation of Grazed Grasslands on the Hortobágy
    50-54
    Views:
    296

    The sward composition of different grasslands on Puszta Hortobágy has been developed according to prevailing abiotic and biotic factors. The abiotic conditions have been more or less constans for long periods of time, and the abiotic factors are determined by ecological conditions (climate, soil, topography). Among biotic factors grazing of herbivores was important in the development of Hortobágy grasslands for centuries (Sipos and Varga, 1993). Result of three-year investigations on the sward composition of grasslands utilised in different ways are presented. Data on ground cover, number of plant species, representation of different plant groups (grasses, sedge and bent-grass, herbs, legumes) and weeds are reported from six different grazed grassland types from Puszta Hortobágy.
    In 1999-2001 a sward composition survey was conducted. Sample areas of 2x2 m2 were marked out in three replicates: on temporarily waterlogged grassland grazed by cattle (A), on dry grassland grazed by cattle (B), on dry grassland grazed by sheep (C), on dry grassland grazed by buffaloes (D), on dry grassland grazed by buffaloes and geese (E), on dry grassland cut for hay in May then grazed by geese (F). On the sample areas sward composition of grasslands was estimated according to Balázs (1949).
    The average ground cover of different grasslands ranged between 60 and 100% (Table 2). The lowest value was found for grasslands C and E, which are grazed by sheep (C) and buffaloes and geese alternately (E). In these grasslands were some open spaces, on the other grasslands completely closed swards covers were observed.
    The species diversity of these natural grasslands are high (Table 2). The grassland F, which were cut for hay in May had the lowest diversity (17-21). The highest number of species was found on grassland A and B (32-51), on other grazed grasslands (C, D, E) had 29-48 species.
    The different plant groups had different representation in the total ground cover (Table 3). The number of herbs was always higher then that of grasses, but the cover of herbs was lower then that of grasses. The legumes and the sedge and bent grasses were present in high abundance in grassland A, but in the other grasslands were not.
    The composition of herbs should be a warning for future utilisation systems on some grasslands of Hortobágy. Some species of herbs, e.g. Achillea millefolium, Artemisia vulgaris, Carduus acanthoides, Cirsium arvense, Cirsium vulgare Eryngium campestre, Galium mollugo, Galium verum, Ononis spinosa, Rumex crispus, Verbascum phlomoideus, Phragmites australis can be invasive on short grasslands.

  • The effect of crop coverage on the daily dynamism of the soil’s CO2 emission
    97-102
    Views:
    375

    Nowadays one of main goals of international ecosystem research the measurement of greenhouse gases (CO2, N2O and CH4) in different places. The fluctuation of these greenhouse gases – quantity and trend in the case of CO2 and CH4 – could be diverse with atmosphere because it depends on several effects of factors like climate, soil type, vegetation. In grassland out of the three greenhouse gases which fill a part in gas emission, in the case of CO2 soil and vegetation are the most important factors (Soussana et al., 2007).
    In the aspect of global carbon balance grasslands are very important by their large area extension, total carbon content, organic content store (10% of the global carbon storage) (Lemmens et al., 2006). In this summer measurements were carried out to determine CO2 emission of the soil from different soil surfaces like grass covered and bare soil surface during a whole day.

  • Harvesting system established for the utilisation of Miscanthus sinensis ‘tatai’ “energy cane” in biomass power plants
    143-150
    Views:
    279

    The increasing demand for energy worldwide and the resulting environmental impacts of fossil fuels forced many countries to turn to renewable energy resources as a clean and sustainable alternative. More than a third of Europe’s binding renewable energy source target of 20% by 2020 will come from solid biomass for electricity and heating according to the National Renewable Energy Action Plans submitted by member states of the European Union (EU) to the European Commission. To achieve this goal long-term yield studies in renewable energy plants are important to determine mean annual biomass and energy yield, and CO2 emission. Field experiments worldwide and also in Europe have demonstrated that Miscanthus, a fast-growing C4 rhizomatous grass can produce some of the highest biomass and energy yield per hectare of all potential energy plants. Miscanthus is a plant that originates from the southern slopes of the Himalayas. It was bred for the Hungarian climatic conditions in 2006 under the name of Miscanthus sinensis ‘Tatai’ (MsT). The species has high frost and drought tolerance and high energy value. This is why there is growing demand for the biomass (lignocellulose) produced by growing this plant. The biomass, produced from the high yield energy reed, can be transported to power plants in large quantities, in forms of bales. Its household consumption is not yet significant. This study presents the external features, characteristics, propagation and plantation process of MsT energy reed. The study also demonstrates the harvest technology of the species worked out between 2009–2012 in Tata, Hungary and the options of supplying to biomass

    power stations.

  • Findings on the cultivation of potatoes in organic farming
    113-116
    Views:
    252

    This paper explores the effectiveness of organic and plastic mulching for potato production in the Czech Republic. The mulching with chopped grass (GM) and black textile mulch (BTM) were compared to non-mulching control variant (C) with mechanical cultivation. Especially in plots with BTM were first formed ridges and covered by the black polypropylene non-woven textile and then they were planting. During vegetation the infestation of Colorado potato beetle (CPB), weeds biomass, course of soil temperature and soil water potential were assessed. The results showed that surface of GM had a positive effect on soil temperature reduction, soil water potential depression. This study also indicated a positive effect of GM on the larvae of CPB diminution, on the other hand higher incidence of larvae and higher defoliation was observed in BTM. GM had a significant effect on the yield of potatoes. The yield of ware potatoes was higher by 27 % higher on plots with GM and by 16 % lower on plots wit BTM in comparison with C. NeemAzal T/S decreased statistically significantly % of defoliation and increased yield of ware potatoes by 35 % in comparison with control.

  • The Effect of Utilization Systems on the Sward Composition, Yield and Sheep Carrying Capacity of Extensive Grasslands
    16-18
    Views:
    212

    We analysed the effect of the sheep grazing, the grass cutting and mixed utilization methods on plant composition, yield and live-stock keeping capacity of extensive Achilleo-Festucetum pseudovinae grassland in the 1996-2000 research period. Analysing the extensive utilizations effects on chanching of the plant composition of extensive grassland established that due to the cutting utilization method the area covering rates of gramineous and usefull weeds were the highest while the grazing utilization-method caused the briggest area covering rate for legumes and unusefull weeds. Analysing the utilized fibrin-fodder yield established that the single utilization methods could not produce the maximum yield and live-stock keeping capacity on the treathea grassland type. Because of things mentioned above we must use the mixed utilization methods to save the maximum phytomass.