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Recovery of grasslands in former croplands using the combination of seed sowing and hay transfer
5-11Views:171In accordance with general trends in agricultural and natureőconservation practice in Europe, grassland restoration and traditional grassland management has gained increased importance in Hungary. In grassland restoration using of low rates of seed (less than 30kg/ha) and hay cover is suggested. In the present paper the effect of hay cover combined with low rate of seed (25 kg/ha) is studied in early grassland recovery. We aimed at to answer the question whether or not the speed of grassland recovery can be increased with a combined use of seed sowing and hay cover. The establishment of Festuca species was favoured by hay cover combined whit seed sowing. The emergence of shortlived weeds was significantly lower on most of the fields treated with hay cover and seed sowing. The species richness and diversity of early weeds did not differ significantly in fields sown only and fields treated both with seed sowing and hay cover. Our results suggest that the combination of seed sowing and hay cover is successful in fields, where high rate of weed invasion is possible, thus intensive post-restoration management is necessary.
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Study of the agronomic value of artificial extensive grasslands
28-35Views:172The agricultural value of an extensive, alternativly used grassland with three seed densities (500 seed m-2, 1000 seed m-2 and 1500 seed m-2) and at two sowing times was examined in an established grassland experiment with herbs on sandy brown forest soil in Gödöllő in the spring and autumn of 2002.
The results showed that treatment No. 3 (=1500 seed m-2) had the highest agricultural value. It can be concluded that the highest seed norm resulted in the highest grass cover. Through the estimated agricultural value, we have also proved that the grass established in autumn grows more vigorously than the dicotyledonous species. This follows from the biological characteristics of the two plant groups. The grasses are tolerant towards cold and perennial species, while most of the dicotyledonous are annual and prefer milder conditions.
Grassland areas with the same ecological basis differ greatly as far as their plant composition is concerned, depending on seed density. In addition, the plant composition changes continusly according to sowing time. -
Kaszálás felhagyás hatása helyreállított szikes és löszgyepek vegetációjára
21-29Views:174Grasslands recovered by sowing of low diversity seed mixtures are frequently managed by mowing. However only a few studies focused on the direct effects of post-restoration mowing on recovered grassland vegetation. In this study we followed vegetation changes in 13 recovered grasslands, in 5×5-m-sized exclosures with continuous and ceased mowing in Hortobágy, East-Hungary. We asked the following study questions:
(i) What are the effects of cessation of mowing on the vegetation structure of recovered grasslands?
(ii) What are the effects of cessation of mowing on the abundance of sown grasses, target and weed species?
(iii) Is yearly mowing an appropriate management for the maintenance of recovered grasslands?
Our results showed that the cessation of mowing caused litter accumulation, decrease in total cover and decrease in the cover of sown grasses compared to the continuously mown exclosures. The cover of perennial weeds was significantly higher in unmown exclosures compared to the mown ones. The species composition in mown exclosures remained more similar to reference grasslands than to the unmown ones. Our results suggest that without a regular post-restoration mowing the favourable stage of recovered grasslands can be rapidly vanished caused by litter accumulation and/or by the expansion of undesirable weedy species. We also stress that yearly mowing is solely enough to maintain grasslands recovered by low-diversity seed sowing, but cannot be considered to be enough to recover target vegetation composition.
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Possibilities of restoration of natural or seminatural grasslands: Papers of the „Challenges and Aspects in Grassland Management” conference held on 22-23 May 2008.
19-27Views:303The number of natural grassland restoration projects increased in the last decade in Hungary, and probably the area of restored grasslands will be significantly extended in the next years due to New National Rural Development Program. To contribute to the success of this activity, in this paper we review the most important theoretical and practical aspects of natural grassland restoration methods. In the course of grassland restoration, habitats dominated by grasses and/or sedges have been restored in place of arable lands. In order to perform “natural” restoration, we should consider the ecological conditions of the landscape, and reconstruct natural or seminatural grasslands including of native plant species. Essentially, rehabilitation of natural landscape is supported also by creating new seminatural grassland patches. The basic principles of the natural grassland restoration are:
1. When a spontaneous secondary succession starts to proceed on an abandoned field without invasion of any alien plant species, the re-ploughing of the abandoned field has to be ignored.
2. Generally, the old fields surrounded by species-rich natural or seminatural grassland pathes can succesfully be restorated. Then, as a consequence of newly restored vegetation patches the recovery of the whole landscape can be accelerated. Furthermore, by restoring isolated grassland patches surrounded by arable lands a more diverse landscape pattern could be developed.
3. Spontaneous secondary succession of grasslands should be assisted.
4. The development of typical species composition of a seminatural grassland can be promoted by methods of spreaded hay. For successful process the hay has to be cut in a habitat type similar to ones that will be restored.
5. Applying seed-mix for sowing can be useful to prevent spreading weeds drastically in the early stages of succession.
6. Ideally, the seed-mix is originated from own harvesting or gathering from similar (or the same) habitats. If it is not possible, commercially available seed-mix can be applied, in which the dominant species is the same as in the restored habitat, with similar proportion.
7. Seed-mix consists of alien species has to be avoided.
8. If the composition or structure of the restored grassland is not appropriate after some years, the renewal of the grassland could be necessary. During the improvement process the reploughing of the restored grassland is avoided, but spreading seeds or hay, and direct sowing can be applied.
9. The loading of nutrient is not necessary in any stages of grassland restoration.
10. Applying chemicals is avoided; any herbicides can be used only when extensive invasion of alien plant species occurs.
11. The mechanical intrusions on soil are also avoided.
12. The restored grasslands is required regular or continuous management, which could be a preserving mowing or moderate grazing. The aspects of nature conservation should be considered.
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Digestibility and nutritive value of late mowed grassland
63-69Views:261Nutritive value of a fodder from extensive established pasture was tested. The nutrient content was measured by the Wendeeanalysis and by in vitro ruminant digestibility method. Results of former experiments showed that the nutritive value of an extensive established pasture in the case of late outdoor growing is low. In our results the highest crude protein content was in the year 2002, while in 2003 can be observed a steep decline, which showed in 2004 further decrease. The crude protein values were the highest in case of middle seed norm. The nutritive values of these pastures provide just supply for the demand and it was declined due to the negative N-balance in the rumen. Our results showed that the samples from the year of establishment could possibly be used for preserved feed (6.01 MJ NE l kg-1). The crop from all other years and sowing times did not reach a value of 5.00 MJ NE l kg-1, but approach a level of 4.4 to 4.5 MJ NE l kg-1, thus they would not be suitable for preserved feed. It can be recommended that this late season crop should rather be used for grazing of livestock than as preserved feed.