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ŠUMARSKI LIST 1-2/2003 str. 27     <-- 27 -->        PDF

.1. Zclic: PROBLEMATIKA GOSPODARHNJA PREBORNIM SASTOJINAMA BUKVE I JELH ...


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N= 288,64476 e ft"-"">-... silver fir ... 524 trees


N= 322,01947 e 0-m948" ... beech ... 450 trees


N = 297,34888 e """--´´´... silver fir (0,6) + beech (0,4) ...495 trees


Tariff line of site class III for silver fir and beech can bee made through
this functions:


v= 0,38-0,015852 d+ 0,0012362 d2 ... silver fir


v= 0,185-0,031711 d+ 0,0016608d2 ... beech


With help of Mayer function of thickness and function for tariff line for site
class III by Suric, the normal stem wood is calculted 317 m2/ha for silver fir,
258 m2/ha for beech and 294 m ´/ha for mixed population of silver fir (0,6) and
beech (0,4).


Transition time for mixed forest silver fir and beech is given for diameter
classes and decrease in higher classes. The average are 9 years for beech and
11 years for silver fir. For the forest compartment 56a it is equalized by exponential
function:


"s"133


T= 177,47288-d.


From distribution of diameter classes for silver fir and beech arithmetic
middle is calculated this way: da = 32,21 cm, and arithmetic middle volume
1,00 m3. Standard deviation of diameter classes is: oa = 13,70


According to earlier type of management as regular stands, curve of distribution
of diametar classes have a shape of bell. Correction of distribution
for diameter classes is made with Beta -distribution:


M33


f(d) = 0,017/091 -I((d-10,0) (75,0-d)"´"))


Number of trees per hectare is shown in table number 5. Curve of equaling
is asymmetric on the left side (positively) because of the exponent a < y,
(a= 0,433, and exponent y= 1,679).


Normal distribution of diameter classes is asymmetrically bell shaped and
it stands for 9 5-y ear-regular stand. Management of stand in past was made
acording to nature laws of regular stand. Number of trees per hectare is 294.


Mentioned distribution of diameter classes for silver fir ond beech in stand
shows characteristic structure of regular stand. We can get that conclusion
from equal distribution by Liocourt:


N= 135,851 -e "´""´"´´´,


which devotes a lot from normal and mentioned distribution (graph I).


According to projected normal volume of 293,57 m2/ha and increase over
10 years we can cut (as much as) 123,30 m3/ha. It is possible to mark a whole
volume over diameter of 60 cm (28,40 nvVha) and other 94,90 m´/ha on
account 10years growth (table 5).


Volume of trees cutting is necessary to make for each forest compartment,
and wholw volume for cutting which can be calculated by formula:


E= M-((l -(1/1,0-p´))/,


for all forest compartments and can be used for checking and correcting
volume for cutting in each compartment.


It is recommended that after classifying stands according to site class, volume
proportion and previous age structure we have determine relevant structural
biometric parameters which can be comparated to placed models of
normal structure in selection system by number of trees and volume per
hectare. It is necessary to determine the details of forest compartments selection.


Mixed forest associatons of silver fir and beech, which are by measurements
and biometrical parameters under model of normal selection stands,


Sumarski list br. 1-2. CXXVI1 (2003). 11-26