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  • Néhány időjárási tényező és a hozam összefüggése száraz- és üde gyepeken
    39-42
    Views:
    73

    The yield of pastures will be impaired by the climate change as a result of reduced amount of winter and vegetation precipitation and the increasing number of hot days as well as the increase in temperature. Species composition is also due to change, however, this change will be more difficult to be determined as the increasing concentration of glasshouse gases has different impacts on the various components. Grassland is a water demanding culture; droughts reduce yield significantly and these losses should be compensated by an adaptive agricultural technology. On protected and Nature 2000 pastures, comprising giving 50% of Hungarian pastures – strict regulations prevent the application of yield increasing techniques, such as irrigation, fertilization or oversowing. The impacts of the weather may only be compensated to a certain extent by the utilization technology. The effects of 3 utilization systems and some elements of weather conditions with special regard to water supply were investigated on dry and mesic grasslands in the years 2006-2010. On the bases of the results some suggestions are set up for modifying the specifications on pasture utilization in nature conservation areas, by having the first cutting earlier and increasing utilization frequency wherever possible. On dry grasslands, yield was affected most significantly by annual precipitation, the precipitation in the vegetative period showed the second strongest correlation with yield. On mesic pastures, temperature and radiation had the strongest influence on the yield. Here, the significance level in the case of total annual precipitation was lower, whereas the correlation was not significant for precipitation in the vegetative period.

  • Relationship between the diversity and mowing in cleared grassland areas in the Börzsöny mountains
    3-13
    Views:
    67

    Nowadays, mowing has an increasing role in the management of semi-natural and nature conservation areas. Semi-dry grasslands have been formed on cleared areas of forest in the Pannon mountains, which would be reclaimed by forest without use of the areas by humans. In our work we analysed cleared grasslands. The questions we aimed to answer were the following:

    (i) What kind of vegetation changes were caused by different land use types?

    (ii) Is mowing a proper method for grassland management and nature protection in the studied system?

    (iii) Do the species composition and the diversity vary within two years when conditions of precipitation are different?

    In four sampling areas situted in Börzsöny mountains (North-Hungary), we registered the plant species and their cover values in ten quadrats per sampling area. We performed a site assessment in April, June and October, 2013-2014. We analysed the data by using cluster and ordination processes and we compared the sampling areas on the basis of the humidity preference and Shannon’s index of diversity. From nature conservation’s point of view, it is favourable that the cover of Potentilla alba occurring in the area was high. It is a specialist plant species with low stress resistance. However, due to tourism, it occured less frequently in the area and Bromus erectus became dominant instead. The species whose cover was more extensive in areas not affected by tourism – for example Alopecurus pratensis, Galium verum, Carex praecox, Trisetum flavescens – occurred less frequently in areas affected by tourism. On the short run, species did not completely disappear due to the changing conditions but their abundance decreased, as has been already supported by other surveys. The ordination analysis showed that the composition of species considerably differed with the portions of land cultivated in different ways. The change of the cover values was apparent not only in the case of the dominant species but of also in case of species with smaller cover. The decrease of diversity, the change of plant cover, the decrease of number of sensitive species as a result of tourism are typical phenomena all over the world. The Shannon’s diversity records showed that due to human presence and trampling the diversity declined. It was considerably lower in the year with less rain. In the year with more rain the diversity of species was considerably higher, however, the difference in between the surveyed areas was large. All these examples draw attention to the important role of environmental factors alongside the human factors. The water reserve also influences the productivity of grasslands and water has primary importance in the structure of plant communities. According to the survey, in the two areas not affected by tourism, in the rainier year the difference between the humidity preference of the species of the dry and the less dry patches became similar. On these areas, there were more species with higher humidity preferences in the rainier year, however, this tendency could not be observed in the rainier year on areas affected by tourism. The areas affected by tourism may react in a less flexible manner to the change in precipitation conditions. Based on our analysis, we can conclude that the surveyed semi-dry grasslands are extremely rich in species and therefore proper grassland management plans are needed. To preserve grasslands of high natural value, the impacts of the environmental factors should also be considered in addition to becoming acquainted with the history and the present conditions of landscape use.

  • Pannonian grazed sandy grasslands in the Ipoly Valley
    49-51
    Views:
    49

    The results of global climate change can be observed in climate of Hungary. In the last couple of decades significant have been observed extremes in the climate of Europe due to global climate change (IPCC, 2014), which the irregular alternation of droughts and floods could be traced in the Carpathian Basin (Bartholy et al., 2009, 2014). The river floodplains and adjacent wetlands were outstanding from a nature conservation point of view due to the increasingly exposed to this change (Capon et al., 2013). Because of climatic effects, floodplain areas are even more exposed to the spread of invasive species (Szollát and Schmotzer, 2004; Schmotzer, 2008; Füri 2000; Füri and Kelemen 1997; Čížková-Končalová et al. 2013), and changes in land use also aggravate this problem (Mosner, 2015; Penksza et al., 2012). The aim of this study is to present the impact of extreme climatic situations on vegetation in grazed grasslands. The question was, which Festuca species occurs in addition to this? Can Festuca javorkae or Festuca pseudovina be found. The Festuca javorkae, which was related to Festuca rupicola, could also be problematic, although this species was clarified (Penksza, 2000, 2009a; Penksza et al., 2020, 2021; Markgraf-Dannenberg, 1980) and its species differentiation was shown using molecular studies by Bnauer et al. (2003) and Galli et al. (2006). According to the description of association Salvio nemorosae-Festucetum rupicolae, Festuca rupicola is one of the species of the association that appeared in the present study.

  • Földalatti ökoszisztéma-mérnök fajok szerepe a gyepek fenntartásában
    49-55
    Views:
    90

    In this review we would like to analyze the effects of the subterranean rodents on vegetation using results from research of several taxons in different vegetation types and climate. Ecosystem engineers are organisms that modify, maintain, and create habitats. Subterranean rodents belong to this group. These species have an impact on the vegetation the microtopographical features of the soil and bulk density, they can change the structure, organic matter and moisture content of the soil they reduce the proportion of nitrogen. The fossorial rodents occur almost all over the world (expect Australia and Antarctica). These herbivorous species burrow tunnels under the ground and with this they have an impact on the floral diversity and dominance relations, the structure and composition of the association, the amount of biomass production as well as the distribution of plants and seeds. They can take effect directly with consumption of plants and indirectly with affect the plant-soil relations. At the basis of the results the activity of the subterranean rodents enhanced the diversity in most of the cases (of course there were also negative results and some researcher didn't find any differences between the mounds and the plots with no mounds). Their effect on the biomass was usually negative but they changed the species composition of their habitat at all times. 

  • Different agrotechnical mesures on the ecology and conservation in a wet meadow
    3-15
    Views:
    46

    In grassland management systems, the various agrotechnical elements have to be used in many cases on "primitive grasslands", where the coordination of agricultural and nature conservation tasks is necessary. Here, animal husbandry is the main aspect, which includes the long-term preservation of the quality of the pasture, as well as the most economical use of the pasture and keeping the animals as cheap as possible. The tests were carried out on a grassy area on the border of the settlement of Aba. We examined the vegetation of 8 plots of the same size in the area and the quantitative and qualitative composition of the biomass produced there. In this thesis, we provide data on the vegetation composition and evaluation of the following treatments. The plots and treatments were as follows: I. plot-ventilated; II. parcel-relaxed; III. plot loosened and ventilated; ARC. parcel control; V. plot-ventilated and 15 t/ha manure; VI. plot loosened and 15 t/ha manure; VII. plot loosened, ventilated and 15 t/ha manure; VIII. plot loosened, ventilated and 30 t/ha manure. In each plot, 5 ceenological recordings were made using 4 x 4 m quadrats. The estimated coverage of each species was given in %, taking into account the proportion of grasslands and other species. Among Borhidi's plant ecological indicators, the species were evaluated based on the NB (relative values of nitrogen demand) and WB (relative soil water and soil moisture indicator numbers). The social behavior types (SZMT) were also defined based on Borhidi's work, and the nature conservation value categories (TVK) were defined according to Simon. The lifestyle analysis was performed based on Pignatti's lifestyle types.

    Based on the data, the composition of the vegetation of each plot changed significantly compared to the data of the control plot IV. A direct proportionality can be discovered between the increase in the cover value of the dominant lawn grasses, primarily Festuca arundinacea, Dactylis glomerata, Alopecurus pratensis, and Fabaeceae species (e.g. Lathyrus tuberosus, Lotus corniculatus) and the amount of applied nutrients. Based on the coenological survey of the eight examined areas, the control area (IV.) showed the most natural state, which was confirmed by the species composition and number of species. The IV. plots are close to I., II. and III. for plot recordings, which proves that aeration and loosening do not worsen the condition of the lawn, but rather promote the preservation of its natural state. The VII-VIII. plots have the smallest number of species, but based on the life form spectrum, naturalness indicators, nature conservation value categories and social behavior types, they are not very disturbed habitats.

    No significant difference can be detected between the effect of lawn loosening and lawn aeration, but III. plot, where both treatments were carried out, was closer to the control area. Regarding the effect of the lawn management methods, it was possible to produce a starting data set in the long term (with the same environmental conditions). Overall, the study gave valuable results regarding the age of change occurring during the application of different lawn management methods, and was also effective from an economic point of view.

  • Effects of grazing as anthropogenic environmental factor of natural grasslands in the Hungarian Great Plain, near Bugac
    39-41
    Views:
    46

    The coenological quadrats were made in 1997, 2005, 2010 and 2021 in a sandy grassland which is used as cattle pasture. The quadrats can be sort in three groups. The first group of quadrats was made close to the cattle pen (Zone A: 0-50 m). The second group was made farther (Zone B: 50-150), where the grazing is not so intensive. The third group contains the quadrats which were made farther than 150m (Zone C). The animals use this area rarely, therefor this part of the pasture is undergrazed (Penksza et al., 2010a). The coenological survey was carried out with 2×2 meter squares, recording the cover value. The species names follow the nomenclature of Király (2009) and Engloner et al. (2001).

     

    The rate of species which indicate degradation is the highest near to the cattle pen (0-50m). But farther than 50m the rate of species which indicates naturalness is higher. Lower  nature conservation value can be observed near to the cattle pen. In this area weeds and degradation tolerant species can be found in the highest amount. Their ratio grew in the second zone (50-150m) too in the past few years, but the species which compose the natural vegetation also survived, so the species composition is able for regeneration. With the decreasing of grazing intensity the sample area could meet the requirements of nature conservation.

    Data evaluation was made with considering naturalness state in case of habitats; and on the other hand, according to relative ecological factors of occurring species. A significant change in species composition could be detected. Particularly, deterioration of areas could be experienced. These negative processes are extremely heavy inside and near the animal husbandry farm. Even aggressive, invasive plant species occurred. Among dominant grass species, dominance relations and covering rate of disturbance tolerant Cynodon dactylon and Lolium perenne species have increased, caused partly by overgrazing and trampling as well. A new species, Poa humilis, appeared in the zone “A” in 2020, which is a degradation indicator species and tolerates overgrazing and trampling (Penksza and Böcker, 1999/200; Penksza, 2009). Farther from the farm, rate of degradation showed by vegetation has decreased compared to the areas closer to the farm, however, it has increased even on the farther area between the two time periods. During the preparation of management plans for the grasslands, these data should be considered at a higher rate in favor of preserving natural values,

  • Degradation degree evolution under different grassland management
    35-44
    Views:
    96

    The objective of this manuscript is to clarify the changes in vegetation structure of an extensively managed grassland association under different land use practices. In the grasslands of the Hungarian Great Plain, the westernmost part of the Eurasian steppe, the largely decreasing grazing livestock numbers and the almost disappearing pastoral grazing make the topic very topical. We analysed the last 4 years of the study period 2009-2020 and found that the lowest degradation rates were measured in the meadow utilisation management, with values ranging from 0.277-0.463 in the 11th year of the experiment. And the highest degradation values were measured in the treatment with the overgrazing mode, with degradation degrees 3.43-5.0 in the 11th year of the experiment. In the treatment demonstrating the effect of overgrazing, we measured a high increase in the cover value of the weed Hordenum murinum, which is very dangerous for sheep, between 2017 and 2020, with an average of 107.6%.

  • Biomass of the sandy grasslands along the Danube
    31-35
    Views:
    91

    Festuca taxa are important grassland species in the pannonian vegetation, and are defining members of it where conditions are too extreme for most plants. Based on grassland management surveys, habitats of narrow-leaved or small Festuca species are an indicator of poor productive capacity, but are important in terms of nature conservation. The significance of these grasslands are likely to be increasing in line with climate change and expanding dry habitats.

  • Comparative investigations of biomass composition in differently managed grasslands of the Balaton Uplands National Park, Hungary
    49-56.
    Views:
    77

    Phytosociological and biomass samples were collected in two territories of the Balaton Uplands National Park (Hungary) dominated by grassland habitats. Samples in the Tihany Peninsula had been taken in a pasture of Hungarian Grey Cattle. Studies were broadened to four areas of the Tapolcai Basin, Badacsonytördemic (undergrazed and overgrazed pastures, hayfield, control area). The areas were suitable for following up the changes of vegetation and production in every grazing season of a year. We evaluated the changes of species composition and ground cover, the measure of possible regeneration or degradation, and the changes of these factors from the viewpoint of feeding value. Covering rates of the grassland associations have doubled and species composition has improved in the Tihany Peninsula, however, forage value has not increased, due to the change in land use in favour of the natural area that is converting into grazing field. In case of the Taplocai Basin, low number of species (20 to 30) was detected in the undergrazed pasture and the control area. About one month per year grazing time in the undergrazed area was not enough to achieve a better state for species diversity, and the amount of forage remained high. The overgrazed pasture carries a low forage value and contains a high number of weed species, despite the spectacularly high total number of plant species (38 to 39), consequently, grazing pressure has to be decreased. Although the number of species is lower in the hayfield (26 to 28), species composition and ability for forage supply is much better, showing that the proper management of the area is taken here.