Disturbances on a wooded raised bog : how windthrow, bark beetle and fire affect vegetation and soil water quality?

Autor: Kučerová, Andrea, 1973-
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Jazyk: angličtina
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Druh dokumentu: Non-fiction
ISSN: 1211-9520
Abstrakt: Abstract: Pinus rotundata dominated peatbog (Žofinka Nature Reserve) in the Třeboň Basin, Czech Republic, was affected by "natural" disturbances: wind damage (1984), followed by a bark beetle attack, and fire (1994, 2000). Phytosociological relevés were used to document vegetation. Soil water chemistry was compared in three differently affected stands: (1) an undisturbed Pinus rotundata bog forest, (2) a windthrow - bark beetle affected stand and (3) a site burned by wildfire in 2000. The species composition of the windthrow - bark beetle affected sites and the undisturbed P. rotundata bog forest differed mainly in the shrub and tree layers. Burned sites were partly colonized by anemochorous species (e.g. Taraxacum sp. div.) that disappeared within two or three years after colonization. Bare peat was colonized by bryophytes (e.g. Marchantia polymorpha and Funaria hygrometrica) typical of the disturbed sites, and by Polytrichum sp. div. and Aulacomnium palustre. Most plant species characteristic of the P. rotundata bog forest occurred at the burned sites eight years after the fire, but in different abundances. The edificator of the former community-P. rotundata-was mostly absent. Compared with windthrow followed by the bark beetle attack, fire promoted rapid expansion of Molinia caerulea. Soil water in both the undisturbed P. rotundata bog forest and the windthrow - bark beetle affected sites had a similar composition: very low pH values, high P concentrations, low concentrations of cations (Ca²+, Mg²+ and K+) and inorganic nitrogen. The concentrations of soluble reactive phosphorus (SRP) and NH+₄-N were negatively correlated with the groundwater table. Total P, SRP and NH+₄-N concentrations in the soil water at the burned site were by one order of magnitude higher than those in the P. rotundata bog forest, while concentrations of K+, Mg²+ and Ca²+ were only about two times higher
Databáze: Katalog Knihovny AV ČR