ABSTRACT BOOK Sandstone Landscapes ... - Sandstones.org

TVěra Hadincová 1 , Jana Simonová 2 and Iva Köhnleinová 11 Institute of Botany, Academy of Sciences of the Czech Republic, CZ-252 43 Průhonice, Czech Republic(hadincova@ibot.cas.cz)2 Department of Botany, Faculty of Science, Charles University, Benátská 2, CZ-128 01 Praha 2, CzechRepublicInvasive behaviour of Pinus strobus in sandstone areas in the Czech RepublicThe highly broken sandstone areas with species poor vegetation give many possible spots for newlyintroduced species. The species fully making use of the variable environment seems to be the NorthAmerican conifer tree Pinus strobus. Studying P. strobus propagation from plantations we focused on thefollowing tasks:1/ To find all localities of natural regeneration of Pinus strobus in different sandstone areas (Český ráj,Kokořínsko, Adršpaško-teplické skály) and evaluate how they are related to the position, age and extend ofP. strobus plantations.2/ To compare habitat preference for Pinus sylvestris and Pinus strobus natural regeneration.3/ To describe Pinus strobus dispersal and age structure of new stands.4/ To evaluate Pinus strobus impact on composition and abundance of herb and moss layers.Our results revealed that 1/ P. strobus wildings and saplings are distributed mainly under seed trees and intheir surroundings. Only few localities were found further then 100 m. Period of P. strobus introductioninto the area was not significant for area, density and age of new stands. Important was distance from seedstands and their age and area. 2/ Pinus strobus naturally regenerates in wide range of ecological conditions.Its wildings rarely survive on dry, sunny, and windy rock tops or in narrow, wet, and shady valleys. Themost preferable sites were plateaus and upper slopes. Pinus sylvestris regenerates in narrower range ofecological conditions - at open insulated places at rock tops, plateaus and upper slopes. At the last two itcompetes with P. strobus and low shrubs Vaccinium myrtillus, Vaccinium vitis-idaea. 3/ P. strobusfundamentally reduces the composition of understory vegetation. Its population age structure and mortalitypoint to the still increasing number of trees in the area (of Bohemian Switzerland). This behaviourcorresponds with the behaviour of invasive species.