DIGITALNA ARHIVA ŠUMARSKOG LISTA
prilagođeno pretraživanje po punom tekstu
| ŠUMARSKI LIST 3-4/2013 str. 12 <-- 12 --> PDF |
damage. They were classified as lightly browsed if less than 10 % of lateral shoots were damaged. If more than 11 % and less than 50 % of lateral shoots were browsed, including terminal shoot, seedlings were classified as moderately browsed, while plants with even more damage were categorized as heavily browsed. Five characteristic relevés according to the standard Braun-Blanquet method for vegetation sampling were taken (Braun-Blanquet 1964) across the entire area of the reserve. A comparison of vegetation samples from this study with samples from other fir, fir-beech, beech, and hornbeam sites in Slovenia sampled with the same method was done by Detrended correspondence analysis (DCA). Environmental data (altitude, inclination, and stoniness) and Ellenberg indicator values (EIV) for light, temperature, continentality, moisture, and soil reaction (Ellenberg 1988) were added on the ordination plot as a result of regression with ordination axes. Additionally, the nitrogen EIV and Shannon-Wiener diversity index were drawn as isolines onto the ordination plots. Differences in EIV between sites were tested with a one-way ANOVA and the Tukey HSD test. The current shape of the forest reserve was transcribed onto an old military map, which was created between 1763 and 1787 (Rajšp 1997) and geocoded (Figure 2). In this way we were able to determine how the land in the area of the current reserve was used at the time the map was created. The large permanent research plot was divided into 10 smaller areas 25 x 40 m in size. In each area a dominant tree was identified according to its social status, dbh, height, developmental tendency, and vitality. All dominant trees were cored to the center at 1 m height and their dbh and height were recorded. For comparison we also drilled three dominant trees outside the forest reserve following the same methodology, hence the cumulative sample included 13 trees. The samples were prepared for analysis with established dendroecological procedures (Stokes and Smiley, 1968). The samples were digitized and ring widths were measured to the nearest 0.01 mm with WinDENDRO software. Age differences in dominant fir and spruce trees were analyzed with the Mann-Whitney U Test. Data was analyzed in Microsoft Excel Version 2003 and R Version 2.13.0 (R Development Core Team, 2011). Results of research Rezultati istraživanja Forest history – Povijesne prilike Analysis of the old military map (Figure 2) showed that the shape of today’s reserve was at the border between pastures and forests at the time the map was created (1763–1787). At that time significantly more area was devoted to agricultural land (pastures, fields, vineyards) than today. Also, the age structure of the analyzed dominant trees showed fairly uniform structure. Mean age of dominant firs at 1 m height was 79.4 (±13.7) years and for dominant spruce trees 89.4 (±2.7) years. Minimum ages for fir and spruce were 58 and 86 years, respectively, and maximum ages were 100 and 92 years, respectively. There was a tendency towards greater mean height in spruce, but it was not statistically significant |