|ORIGINAL SCIENTIFIC PAPERS|
|Lukić, N.||UDK 630* 561 +182.2 (Fagus sylvatica L.)|
|Dendroclimatology Analysis of Common Beech (Fagus sylvatica L.) on Papuk pdf HR EN||3|
|Božić, M., Čavlović, J.||UDK 630* 622 + 624 + 522 (001)|
|The Relationship Between Dominant Height. Dimension of Crop Maturity and Normal Growing Stock in Selection Stands pdf HR EN||9|
|Summary: According to the current Forest Management Act, selection (variable aged) forests in the Republic of Croatia are managed with the normal model method, that is, according to the “New system of selection forest management”. Klepac (1961) based “The new system of selection forest management” on Susmel’s correlation for the fir, Collete’s for the beech and on šurić’s site quality classes.In Susmel’s and Colette’s correlation, the mean height of dominant trees is the measurable parameter of a concrete forest representing the link between the forest and its normal model. The normal model could therefore be constructed for each concrete case on the basis of the measured heights of dominant trees. However, there is a problem of reducing the mean height of dominant trees (in relation to those used by Klepac), arising from:|
a) different ways of defining the notion of dominant height;
b) lowered dimension of physiological maturity in relation to crop maturity.
The authors studied the extent to which the reduction of the mean height of dominant trees (resulting from different definitions of dominant height or from achieving of a certain diameter of crop maturity with management methods) influences the decrease in the growing stock based on the “New system…”.
The authors have used several parameters in their research:
a) Klepac’s original normal model for the II, II/III and III site class corrected to the German diameter degrees with the physiological maturity and the dimension of the crop maturity of 70 and 60 cm;
b) four concrete stands, of which two were the managed selection stands from the Management Unit “Milanov Vrh” (compartments 2b and 13a), in which the distributions of tree numbers end with diameter degrees of 77.5 and 62.5 cm, and two were transitional stands from the Management Unit “Crni Lug” (compartments 39c and 61b), where the distributions of tree numbers end with the diameter degree of 97.5 cm; and
c) the mean height of dominant trees for the Management Unit “Belevine” measured for the Management Programme for “Belevine”.
The dominant heights were defined according to Susmel and Weis. The height of the tallest tree was measured in every hectare of the Management Unit “Belevine”, and the mean height of dominant trees was calculated as their mean value.
A reduction in the mean height of dominant trees or the dimensions of crop maturity leads to a decrease in the growing stock of the newly constructed normal model. The decrease by one meter per height is almost constant and amounts to about 11 m3/ha for the III site class at the maturity dimension of 60 cm, up to 16-17 m3/ha in the II site class with physiological maturity, or 17-18 m3/ha in the compartment 39c located in the II site class, but its tariff is slightly higher than the Šurić-Pranjić tariff. The maximal relative decrease in the growing stock is 146.31 m3/ha or 37.38 %. The decrease percentage by 1 meter per height ranges from about 3.1 % for the II site class with the maturity dimension of 60 cm to 4.1-4.2 % for the III site class with physiological maturity.
In order to avoid the decrease in the growing stock of the normal model caused by different definitions of dominant heights, the original Klepac’s normal model corrected to the German diameter degree should be used in managing selection forests.
Key words: dominant height; growing stock; maturity dimension; normal model
|Franjić, J., Škvorc, Ž., Čarni, A.||UDK 630* 188(001)|
|Numerical Analysis of Phytosociological Releves in Beech-Fir Forests (Abieti-Fagetum s. l.) in Croatia pdf HR EN||19|
|Šajković, A.||UDK 630* 120 +UDK 301.153 (001)|
|The Influence of the Quality of Life on Ecological Alttitude pdf HR EN||27|
|Sabadi, R.||UDK 630* 904|
|Portugal, a Brief Note on its Forestry and Forest Industries pdf HR EN||35|
|Antonić, O.||UDK 630* 181 + 181.3|
|Is the Pedunculate Oak species of Climatogenic Distribution in Croatia? pdf HR EN||45|
|Dimitrov, T.||UDK 630* 432|
|The Conclusion of the Croatian Government and the Proposal of Preventive Forest Fire Protection Programme in the Republic of Croatia pdf HR EN||57|
|Tonković, D.||UDK 630* 375|
|Forest Railways in Croatia pdf HR EN||63|