DIGITALNA ARHIVA ŠUMARSKOG LISTA
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ŠUMARSKI LIST 9-10/1963 str. 22     <-- 22 -->        PDF

4. ZAKLJUČAK. Svrha rada je da se prikaže ovisnost drvne mase stabla
o promjeru krošnje i visini te da se izrade tablice drvnih masa sa ulazima:
promjer krošnje i totalna visina uz upotrebu formule
log m = a + b log d + c log h


Rezultati regresione analize pokazuju da je drvna masa proporcionalna (približno)
prvoj potenciji promjera krošnje i drugoj do trećoj potenciji visine stabla,
dakle obrnuto nego što je to sa prsnim promjerom i visinom (gdje je drvna
masa proporcionalna kvadratu prsnog promjera i prvoj potenciji visine). Interesantno
je da su kod istraživanog materijala tj. jelovih stabala sa silikatnih i
vapnenačkih staništa u Gorskom Kotaru i jasenovih stabala sa tri staništa (tri
tipa šuma) i Posavskim šumama dobiveni vrlo slični iznosi parametara, iako je
jela skiofilna vrsta, dok je jasen izrazito heliofilna vrsta. U svakom slučaju potrebna
su još daljnja istraživanja u tom pravcu. Tablice drvnih masa nisu
donesene radi štednje u prostoru, no pomoću podataka u tabeli lako se mogu
postaviti regresione jednadžbe i izračunati tablični podaci, odnosno konstruirati
nomogram.


LITERATURA:


Halaj, J. Frispevok k odhadu drevnej hmoty s leteckej snimky, Brno 1949.
Sipurr. S. H. Forest Inventory, New York, 1952.
Tomašegović, Z. O pouzdanosti aerofototaksacije za neke dendrometrijske potrebe


šumskog gospodarstva.


Summary


The aim of this work is to represent the dependence of the tree volume on
the crown diameter (D) and height (h), and to prepare volume tables with entries
of the crown diameter (D) and height (h).


For the investigation were chosen two of the most important species in
Yugoslavia, i. e. Silver Fir (Abies alba Mill), and Norrow-leaved Ash (Frax nus
angustifolia Vahl). Sample trees of Fir were felled in the even-aged stands of the
forest community Blechno-Abietum, as well as in the selection stands of the
forest association Fagetum abietetosum. Sample trees of Ash were felled in three
var ous types of Ash forests in the bottom lands of the Sava River. (The number
of sample trees n is visible in the table).


. At first it was shown graphically on the log-logarithmic coordinate paper that
for the regression equation one may use the formula


logm = a 4- to log d + clogh


´ The results of the adjustment according to the method of least squares show
that the volume of the tree is directly proportional to the 2—3 powers of the
tree height, and to the first power of the crown diameter (hence nversaly then is
the case of the diameter b. h. and the height, where the tree volume is proportional
to the square of the diameter b, h. and to the first power of the height). The
results obtained are in conformity with the data of Spurr. It is interesting that
in Fir in even-aged and selection stands as well as in all the three types of Narrow-
leaved Ash stands were obtained very similar results though the Fir being an
expressly skiophilous, and the Ash an expressly heliophilous species.


In the table are given the amounts of parameters, their standard errors, the
standard deviations round the fitted curve, and the correlation coefficients of the
multiple correlation RMS and R134.