DIGITALNA ARHIVA ŠUMARSKOG LISTA
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| ŠUMARSKI LIST 5-6/1971 str. 25 <-- 25 --> PDF |
U hrastovim sastojinama, mlađim od 70 godina, za postotak volumnog prirasta primjenjivati formulu: 1000 1 p = . — D —5 T U hrastovim sastojinnama, starijim od 70 godina, za postotak volumnog prirasta primjenjivati formulu: 1000 1 p = . — D T LITERATURA Chapma n H., Meye r W.: Forest mensuration, New York 1949. Emrovi ć B.: O konstrukciji lokalnih jednoulaznih drvnogromadnih tablica (tari a), Šumarski list, Zagreb 1953. Kie p a c D.: Rast i prirast šumskih vrsta drveća, Zagreb 1953. Klepa c D.: Opadanje prirasta u našim vrijednim hrastovim šumama, Šumarski list, Zagreb 1969. Pard e J.: Dendrometrie, Nancy 1961. Patron e G.: Dendrometria, Firenze 1963. Pranji ć A.: Sastojinske visinske krivulje hrasta lužnjaka, Šumarski list, Zagreb 1970. Proda n M.: Holzmesslehre, Frankfurt am Main, 1965. Ministere de 1´ agriculture direction generale des eaux et forets: Manuel pratique d´amenagement, Paris 1964. AN EXPERIMENT ON DISPLACEMENT OF HEIGHT CURVES IN EVEN-AGED PEDONCULATE OAK STANDS WITH RESPECT TO THEIR AGE By Prof, dr DUŠAN KLEPAC Institute for Forest Research, Faculty of Forestry, Zagreb. In the forest management literature a well-known fact is that the choice of a tarif (single-entry volume table) depends upon a variety of factors. But while in the selection forests the chosen tarif remains more or less constant, this is not the case in even-aged stands. In the latter ones the tarif should be changed;.thus, for instance, if we have calculated the volume of a young stand according to a tarif, then, after twenty years, the volume of this same stand should be calculated according to a higher tarif. The reason lies in that the height curve in even- aged stands is moving upward and in the technical literature it is spoken about the socalled »displacement of the stand height curve« (German: Verlagerung der Bestandeshöhenkurve; French: desplacement des courbes des hauteurs des peuplements equiennes). About this Parde writes in his »Dendrometry« (1961) als follows: »A la difference de la courbe des hauteurs des peuplements jardines, celle des peuplements equiennes n´a pas du tout tendance a etre immuable dans le temps: eile se deplace vers le haut au fur et a mesure que le peuplement vieillit«. »As distinguished from the height curve of the selection stands, the one of the even-aged stands has not at all a tendency to be immuable within the time: it shifts upwards in proportion as the stand grows older«. This is a well-known fact. Howewer, it is rather unknown at what rate the height curve shifts in an even-aged stand. We are interested in this because a knowledge of the dynamics of height curve displacement makes possible to solve the problem of choosing the tarif. I was faced with this problem when determining |