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Regeneration of Nardus stricta subalpine grasslands in the Giant Mountains [Krkonose]

100%

Hejcman M., Nezerkova P., Pavlu V., Gaisler J., Lokvenc T., Pavlu L.

Acta Societatis Botanicorum Poloniae

2005

tom 74

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.

Farmer decision making and its effect on subalpine grassland succession in the Giant Mts., Czech Republic

84%

Hejcman M., Pavlu V., Hejcmanova P., Gaisler J., Hakl J., Rauch O.

Acta Societatis Botanicorum Poloniae

2006

tom 75

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.

Geographic patterns of genetic diversity of Pinus mugo (Pinaceae) in Central European mountains

67%

Dzialuk A., Boratynski A., Boratynska K., Burczyk J.

Dendrobiology

2012

tom 68

The genetic diversity within and among twelve populations (379 individuals) of Pinus mugo from the Giant Mts., Carpathians and Alps was analyzed using ten chloroplast microsatellite markers. A stepwise mutation model (SMM) for microsatellite loci was used in order to estimate divergence between populations and provenances from three mountain ranges. High levels of genetic diversity and significant differentiation were found among the three population groups. The populations from Giant Mts., Carpathians and Alps were strongly differentiated between each other, while differences among populations within these massifs were much lower. The pattern of genetic structure observedin dwarf mountain pine can be characteristic in conifers with a disjunctive geographic distribution. The significant genetic structuring among isolated parts of the geographic range of the species may be a result of an ancient fragmentation andlong lasting geographic isolation between the Giant Mts., Alpine and Tatra populations of P. mugo.

Ograniczanie wyników

2 Acta Societatis Botanicorum Poloniae

1 Dendrobiology

2 Gaisler J.

2 Hejcman M.

2 Pavlu V.

1 Boratynska K.

1 Boratynski A.

1 Burczyk J.

1 Dzialuk A.

1 Hakl J.

1 Hejcmanova P.

1 Lokvenc T.

1 Nezerkova P.

1 Pavlu L.

1 Rauch O.

1 2012

1 2006

1 2005

Wyniki wyszukiwania

Regeneration of Nardus stricta subalpine grasslands in the Giant Mountains [Krkonose]

Farmer decision making and its effect on subalpine grassland succession in the Giant Mts., Czech Republic

Geographic patterns of genetic diversity of Pinus mugo (Pinaceae) in Central European mountains