broj: 11-12/2003
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| IZVORNI ZNANSTVENI ČLANCI | ||
| Vukelić, J., Baričević, D., Drvenkar, D. | UDK 630* 188 (001) | |
| Phytocoenological Characteristics of Beech Forests in Samoborsko Gorje pdf HR EN | 531 | |
| Idžojtić, M., Pernar, R., Kauzlarić, Ž., Abramović, M., Janković, D., Pleše, M. | UDK 630* 442 + 582 (001) | |
| Intensity of Infestation of Silver Fir (Abies alba Mill.) with Mistletoe (Viscum album L. ssp. abietis (Wiesb.) Abrom.) in the Area of the Forest Administration of Delnice pdf HR EN | 545 | |
| Starčević, M. | UDK 630* 423 + 181.3 + 188 (001) | |
| The Effect of Precipitation, Flood and Groundwater on the development of Stands in the Forest Complex “Česma” pdf HR EN | 561 | |
| STRUČNI ČLANCI | ||
| Tomašević, A., Kulić, B., Španjol, Ž., Kružić, T. | UDK 630* 232.4 + 234 + 524 | |
| Development of Black Pine Stands (Pinus Nigra Arn.) and their Ameliorating Role in the Forest District of "Lonja-Biljin", Forest Office Rijeka pdf HR EN | 579 | |
| Summary: The climate of the Rijeka region has a maritime character. According to Köppen´s classification, parts of the Rijeka Commune along the sea belong to class Cfax", with the mean annual air temperature of 13.6 oC and the mean annual precipitation quantity of 1421.2 mm. Relative humidity in this region ranges from the maximum, occurring in December (70 %), to the minimum in July (52 %). The geological substrate of this area is mainly made up of layered limestones, and to a smaller degree of dolomites of different geological ages dating from the Mesozoic period of Jurassic and cretaceous formations. Depending on the geological substrate of either the limestone or the dolomite, a large number of developmental stages and soil forms have developed in this area, such as: - brown red soil (terra rossa) - brown soil on limestone and dolomite (calcocambisol), supporting a culture of black pine (Pinus nigra) In the past, this area abounded in high forests of predominantly pubescent oak (Quercus pubescens) and Montpelier maple (Acer monspesulanum). However, man´s activities led to serious devastation of the forests, while many were also burned in order to convert the soil into agricultural land and pastures. At present, apart from agricultural land, bare rocky terrain and artificial cultures of black pine, this area is covered with the vegetation of xerothermal low forests and garrigues that represent degraded stages of the former high oak forests. Floristic and vegetational research has shown that the studied culture of black pine was established in the climatozonal association of pubescent oak (Quercus pubescens) at the transition between the Mediterranean-littoral vegetation belt in the sub-Mediterranean vegetation zone with the association Querco-Carpinetum orientalis H-ić 1939 and the Mediterranean-mountainous vegetation zone with the epi-Mediterranean vegetation zone characterised by the association Ostryo-Quercetum pubescentis /Ht./ Trinajstić 1997. With regard to abundant presence of hop hornbeam (Ostryo carpinifolia) and a complete absence of oriental hornbeam (Carpinus orientalis), it can be assumed that this is a colder region made up of the community of pubescent oak and hop hornbeam (Ostryo-Quercetum pubescentis /Ht/ Trinajstić 1997). The culture is situated at an altitude of 230 - 275 m. The plot in question is at an altitude of 260 - 265 m. The structural data from the studied plot are as follows: The first measurement of 1969 recorded 426 healthy trees. The next measurement in 1975 recorded 404 healthy trees and 22 dead trees, while the measurement in 1983 revealed 399 healthy trees and 5 dead ones. In the last measurement in 1993, there were 323 healthy trees and 28 dead trees. These data show that in the period 1969 - 1993, the number of healthy trees dropped by 105 individuals. In the same period 55 dead trees were recorded. During the period between the first and the last measurement, 77 trees, for which accurate data of their history is missing, disappeared from the experimental plot. Since there is an overhead transmission line passing along the edge of the stand, it is assumed that a certain number of trees were cut during its erection, while some trees died. The number of trees per hectare was as follows: in 1969 there were 856 trees, in 1975 there were 852 trees, in 1983 there were 808 trees and in 1993 there were 702 trees. It is noted that in each measurement the basal area was increased regardless of the fact that the number of trees decreased. The total basal area per hectare was as follows: in 1969 it was 43.08 m2, in 1975 it was 45.42 m2, in 1‚983 it was 48.50 42 m2, and in 1993 it was 54.30 m2. The data relating to the volume show the following production per hectare: in 1969 it was 236,324 m3, in 1975 it was 246,436 m3, in 1983 it was 269,086 m3, and in 1993 it was 315,026 m3. During the entire observed period, the culture achieved the highest volume production of 45.94 m 3/ha in the last decade. During the last measurement, 28 dead trees with a total volume of 12,755 m3 were registered in the experimental plot. Since this is the culture of black pine in which no new trees occurred between the measurements, the increment equals the differences in the volume between individual measurements. Accordingly, the increment was as follows: in 1969 - 1975 it was 10.12 m3/ha, in 1975 - 1983 it was 22.65 m3/ha, and in 1983 - 1993 it was 45.94 m3/ha. The absence of Croatian normal models and yield tables for the cultures of black pine does not allow comparisons with some optimal parameters. For this reason, certain treatments and decisions will be applied on the basis of the real condition and the appearance of the culture in the field. The mean plot tree has a breast diameter of 31 cm, and the culture is 98 - 105 years old. The analysis of five model trees shows that the mean plot tree achieved different heights ranging from 10.10 m to 13.10 m. The culmination of the height increment occurred between 10 and 15 years of age and reached 0.33 m. The current diameter increment ranged from 0.95 - 1.01 cm for individual analysed trees, with the culmination also taking place between 10 - 15 years of age. The culmination of the volume increment occurred at the age of 32 on average for all five trees and amounted to 0.00596 m3. The period of maturity occurred at the age of 54. Manna ash (Fraxinus ornus) is the most represented tree (16,000 - 39,000 plants/ha) in all height classes. A higher number of pubescent oaks (Quercus pubescens) (2 - 12,000 plants/ha) and hop hornbeams (Ostrya carpinifolia) (600 - 2,500 plants/ha) have been noted on the sun-exposed side, as well as a considerable number of buckthorn (Rhamnus intermedius) (106,000 - 245,000 plants/ha) and dogwood (Frangula rupestris) (599-19,000 plants/ha). On the shaded side, hop hornbeam (Ostrya carpinifolia) is rather rare, which is also the case with pubescent oak (Quercus pubescens), while Montpelier maple (Acer monspessulanum) is relatively abundant (600-4,300 plants/ha). Buckthorn (Rhamnus intermedius) was not found in this part of the culture (plots 3 and 4), but there was a considerable number of blackthorn (Prunus spinosa) (200 - 7,500 plants/ha). Turkey oak (Quercus cerris) was also found in several locations. The distribution of young growth and young plants according to height classes is a good indicator of the conditions in which these plants occur and develop. It points to a very intensive progressive succession of autochthonous vegetation. The tables show that the span in terms of height classes ranges from 25 to 500 cm, while the number of trees in higher classes indicate better conditions of natural regeneration. Since not one young tree of black pine was found in the plot, it can be concluded that these conditions are not suitable any more and that black pine has performed its ameliorative role and created conditions for the arrival of autochthonous vegetation. On the basis of the real condition in the field and the problem of maritime karst forests, our primary task involves the following: Regenerate the existing pine cultures, which will, as pre-cultures, create the conditions for the return of autochthonous elements in the foreseeable future. Protect the cultures from abiotic impacts, cattle and man, as well as fires and insects. Open the canopy slowly and carefully in order not to lose young deciduous growth. Gradually transform the existing autochthonous young growth into permanent stands with more valuable species (pubescent oak (Quercus pubescens), hop hornbeam (Ostrya carpinifolia), Manna ash (Fraxinus ornus) and others). Forest functions of general benefit cannot be expressed in numbers that would describe these functions in more convincing terms than words. These functions are only noticed when incalculable damage has occurred with farreaching consequences. Only the most important of these indirect benefits are mentioned here: - protection of the soil from erosion and leaching - the impact of forests on the climate - protection of settlements and communications from winds - tourism and recreation For this reason, these functions should be carefully guided towards their economic importance, which includes their tourist-recreational and aesthetic purposes, while their product, wood volume, should be economically utilised. | ||
| Božičević, I., Radočaj, M. | UDK 630* 902 | |
| Forestry in the Region of Slunj pdf HR EN | 597 | |
| Domac, J. | UDK 630* 931 + 238 | |
| Energy Sector Legal Framework for the Forest Biomass and the Renewable Energy Utilisation in the European Union and the Republic of Croatia pdf HR EN | 609 | |