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1

The expansion of Celamagrostis villosa in the Giant Mountains - preliminary results

100%
Hejcman M., Pavlu V., Peterova J., Ricarova P.
Acta Agraria et Silvestria. Series Agraria
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2003
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tom 40
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nr Sek.roln.
The expansion of Calamagrostis villosa into Nardo-Caricion rigidae grasslands has been recor-ded in the Giant Mountains over the last few decades. The grasslands above the upper tree line were used for cattle grazing and haymaking practices for at least 300 years and the expansion of C. villosa has been recorded after the cessation of this management. The response of the C. villosa stands to mowing and nitrogen fertilization was studied in an experiment over a two- year period. Mowing resulted in the fast decrease of C. villosa coverage, canopy height and biomass production. The fertilization (30 kg N-ha-1 per year) was not able to compensate for the biomass production of mown plots. On the other hand, fertilization resulted in only a slight increase in biomass production in non-mowed plots. The number of C. villosa shoots decreased rapidly under mowing, was constant under mowing combined with fertilization, and increased in the fertilized plots. The fast negative reaction of C. villosa to mowing probably indicates its high sensitivity to defoliation and nutrient removal. Its expansion seems to be the long-term reaction of Nardus stricta dominated grasslands to the cessation of defoliation practices. Its expansion can also be supported by nitrogen deposition. Obtained results, with regard to defoliation sensitivity, probably indicate the quick reduction of C. villosa in agriculturally exploited grasslands above the upper tree line over the last few centuries.
2
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Farmer decision making and its effect on subalpine grassland succession in the Giant Mts., Czech Republic

76%
Hejcman M., Pavlu V., Hejcmanova P., Gaisler J., Hakl J., Rauch O.
Acta Societatis Botanicorum Poloniae
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2006
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tom 75
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nr 2
165-174
Nitrogen deposition is generally considered as a main reason for many recent plant expansions, but management changes are often not taken into account. Understanding the effects of agriculture management in the past can be decisive in the explanation of plant expansions at present. In order to understand the spread of Molinia caerulea and Calamagrostis villosa into Nardus stricta dominated subalpine grassland in the Giant Mts. (Krkonoše, Karkonosze), we undertook an experiment to explain farmer decision making and we discussed its effect on grassland succession. We measured mowing productivity, yields, biomass quality and nutrient removal in N. stricta, M. caerulea, and C. villosa dominated swards. With regard to defoliation management performed on the subalpine grasslands for at least 500 years and cancelled after the Second World War, we found the following results and conclusions. 1. Mowing productivity, yield and forage quality were lowest in the N. stricta sward, therefore farmers preferred to harvest C. villosa and M. caerulea stands if they had the possibility to select a sward for mowing. 2. Removal of all nutrients was the lowest in the N. stricta sward. With respect to these facts, the competitive advantage of N. stricta is obvious under long-term scything without fertilization. Consequently, the recent increase of defoliation sensitive species M. caerulea and C. villosa above the timber line must be evaluated with respect to both: termination of agricultural activities and recent nitrogen deposition.
3

Rotational and continuous grazing of heifers in the upland of the Jizerske Hory Mountains

76%
Pavlu V., Gaisler J., Auf D., Mrkvicka J., Santrucek J., Vesela M.
Zeszyty Naukowe Akademii Rolniczej w Krakowie. Sesja Naukowa
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2000
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tom 73
4
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Regeneration of Nardus stricta subalpine grasslands in the Giant Mountains [Krkonose]

76%
Hejcman M., Nezerkova P., Pavlu V., Gaisler J., Lokvenc T., Pavlu L.
Acta Societatis Botanicorum Poloniae
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2005
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tom 74
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nr 3
The origin of Nardus stricta dominated subalpine grassland (Nardo-Caricion rigidae alliance) is a frequently discussed topic in the Giant Mountains (Karkonosze in the Czech Republic). Many researchers considered them, as secondary stands arisen after Pinus mugo removal and by consequent oligotrophization of original plant communities, caused by long-term rough grazing and hay making activities without manuring. On the contrary, they are recognized as natural due to inability of generative reproduction of N. stricta and the very slow vegetative spread there. The aim of this study was to find proofs for generative reproduction of mat grass in subalpine conditions of the Giant Mountains. We identified a Pinus mugo nursery with arable land abandoned in 1956 and compared its vegetation with that of the surrounding area. Dense and homogenous sward dominated by N. stricta developed during the succession on the old arable land for 48 years, and it is an indisputable proof of generative reproduction of N. stricta there. Synthesizing historical facts on human activities in the past and the results of our contemporary vegetation analysis, we conclude that the Nardo-Caricion rigidae grassland was capable to spread relatively quickly, when agricultural activities above the upper timber line were introduced.
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