Forest research and permanent sampling plots on Natura 2000 sites in Slovenia

Potencialna območja Natura 2000, ki so bila predlagana Evropski komisiji, obsegajo več kot četrt milijona hektarov slovenskih gozdov. Z monitoringom ohranjenosti naravnih habitatnih tipov bomo ugotavljali in dokazovali, ali so habitatni tipi in vrste, zaradi katerih so bila razglašena območja Natura 2000, še v ugodnem stanju ohranjenosti. V prispevku so predstavljeni kazalnikio zgradbi in pestrosti gozdnih sestojev v dveh gozdnih habitatnih tipih na Slovenskem, ocene variabilnost kazalnikov na raziskovalnih in stalnihvzorčnih ploskvah, ocenjene so spremembe kazalnikov v časovnih obdobjih, primerljivih z 10-letnimi obdobji gozdnogospodarskega načrtovanja. Na območju smrekovih gozdov na Pokljuki in jelovo-bukovih gozdov na visokem krasu smo primerjali kazalnike sestojne zgradbe na podlagi podatkov iz gozdarskih raziskovalnih ploskev in kontrolne vzorčne metode. Predstavljene kazalnike zgradbe gozdnih sestojev bi lahko uporabili za ocenjevanje stanja in sprememb v gozdnih habitatnih tipih na Slovenskem, pri tem pa ne bo treba veliko spreminjati ali dopolnjevati dosedanjega dela na stalnih vzorčnih ploskvah, ki so postale izhodišče za zbiranje podatkov o stanju in razvoju gozdov.The potential Natura 2000 areas, proposed to the European Commission, include more than one quarter million hectares of Slovenian forests. Similarly to the other EU member states, we are going to monitor the conservation status of forest habitat types in Slovenia as well, in order to investigate and argue, whether the habitat types and species, contributing to the proclamation of Natura 2000 areas, are still in a favorable conservation status. The paper discusses the suggested indicators relevant for monitoring stand structure anddiversity in two of the forest habitat types in Slovenia, the estimated variability of these indicators on research and permanent sampling plots, the estimated changes of these indicators in periods of time, comparable with 10-year periods in forest management planning. We tested the indicators for the assessment of stand structure and its changes in the area of spruce forests on Pokljuka and in dinaric fir-beech forests on the high Karst. In both areas it was possible to use the data from forestry research plots and from the continuous forest inventory in order to compare the indicators of thestand structure. The presented indicators of forest stands structure could be used for the assessment of condition and changes in Slovenian forest habitat types without significantly changing or supplementing the existing method of work on permanent sampling plots that became a basis for the collection of data on condition and development of forests