Zmeny druhového zloženia Bábskeho lesa po ťažbe dreva

Abstract

Abstract We present the results of a research which was realized in June 2011 on the location of the Bab forest (SW Slovakia, Nitra loess upland). On 30 permanent areas in the Bab forest there were 117 taxa of higher plants registered. On 12 permanent clear-cut areas were situated 87 taxa and on 18 forest areas 61 plant taxa. a higher number of species was registered on permanent clear-cut areas where heliophilous plants dominated. On clear cuts was also a bigger cover of herbs. There were dominated hemicryptophytes and terophytes unlike forest areas where nano- and makrofanerophytes dominate and where tree and shrub layers have a high cover. The highest frequency of occurrence on clear-cuts (100%) achieved species Geum urbanum and Pulmonaria officinalis and in the forest stand the forest taxa Mercurialis perennis, Hedera helix and Melica uniflora. On all 30 areas dominated indigenous species and apophytes. Four new clear cut areas and 6 open stands arose after realisation of clear and shelterwood fellings in November 2006 and subsequently a change of plant species composition occurred. The logging created suitable conditions for penetration of non-indigenous species from the surrounding (mainly anthropogenic) habitats. That is why there are largely synanthropic and non-indigenous taxa represented on permanent clear-cut areas, which are spreading further to the forest stand as well as distant areas of the Bab forest. Abstract Prezentovane su vysledky vyskumu uskutočneneho v juni 2011 na lokalite Babsky les (JZ Slovensko, Nitrianska sprašova pahorkatina). Na 30 trvalych plochach v Babskom lese sa zaznamenalo 117 taxonov vyššich rastlin. Na 12 trvalych plochach rubanisk sa nachadzalo 87 taxonov a na 18 lesnych plochach 61 taxonov rastlin. Vyšši počet druhov bol zaznamenany na trvalych plochach rubanisk, kde prevladali svetlomilne rastliny. Na rubaniskach bola vyššia aj pokryvnosť bylinneho poschodia. Prevladali hemikryptofyty a terofyty, na rozdiel od lesnych ploch, kde prevladali nano- a makrofanerofyty a vysoku pokryvnosť dosahovalo stromove a krovinne poschodie. Najvačšiu frekvenciu vyskytu (100 %) mali na rubaniskach druhy Geum urbanum a Pulmonaria officinalis a v lesnom poraste lesne taxony Mercurialis perennis, Hedera helix a Melica uniflora. Na všetkych 30 plochach dominovali indigenne druhy a apofyty. Po ťažbe dreva v novembri 2006 vznikli štyri rubaniska a 6 presvetlenych ploch, v dosledku čoho došlo k zmene druhoveho zloženia vegetacie. Ťažba dreva vytvorila vhodne podmienky na prenikanie nepovodnych druhov z okolitych (prevažne antropogennych) biotopov. Preto su na trvalych plochach založenych na rubaniskach hojne zastupene synantropne a nepovodne taxony, ktore sa ďalej širia do lesneho porastu a aj do vzdialenejšich časti Babskeho lesa.