Analysis of forest quantities and species composition alterations using two different methods with comparision

Prispevek analizirana spremenjenost gozdnih sestojev po dveh metodah. S prvo ocenjujemo spremembe vrstne sestave rastlinskih skupnosti, druga metoda pa ugotavlja spremembe sestojev po vi{ini in vrsti lesnih zalog. Za izračun ocene spremenjenosti na ravni osnovnih enot popisa gozdov smo uporabili modelno optimalno in dejansko strukturo lesnih zalog po drevesnih vrstah v gozdnih združbah, popisanih v gozdnih odsekih. Zaradi podatkov, potrebnih za izračun, smo v analizo vključili le odseke, v katerih so ugotovili samo eno gozdno zdru`žo. Prikazujemo rezultate analize na ravni gozdnogospodarskih območij in gozdnih združb. Rezultate na višjih ravneh velikosti gozdnih površin smo dobili s tehtano aritmetično sredino rezultatov osnovnih izračunovn a ravni gozdnih odsekov. Rezultate ocen spremenjenosti smo prikazali tudi prostorsko in naredili primerjavo obeh metod.The article analyses composition alterations in forest stands using two methods. In the first, composition alterations in types of plant community areestimated and in the second, composition alterations in stands according toamounts and types of wood stock are established. To assess composition alterations at the level of basic units of forest inventory, the optimal and actual structure of wood stock was used in models according to tree types in forest communities within forest tracts. The data needed for calculations required analysis only of tracts containing one forest community. Results are shown at the level of forest management region and forest community. Results at higher levels of forest area were obtained using a weighted arithmetic meanof results from basic calculations at the level of forest tracts. The results of composition alteration assessment are also shown by area and comparisons were made of both methods used