Productivity differences between southern and northern slopes of Southern Carpathians (Romania) for Norway spruce, silver fir, birch and black alder (original) (raw)
Related papers
Central European Forestry Journal, 2021
Value production is one of the most important information for comparing different tree species composition and management strategies in forestry. Although the value production of forest stands is affected by various factors thinning can be considered as one of the most important one. This paper aims at the evaluation of qualitative and value production in mixed Norway spruce (Picea abies [L.] Karst.), silver fir (Abies alba Mill.) and European beech (Fagus sylvatica L.) stands, which were managed by crown thinning for a period of 44 to 50 years and/or left to self-development. More than 1,500 individual trees aged from 61 to 132 years from 15 subplots established in western part of the Low Tatras Mts. and the Great Fatra Mts. in Slovakia were assessed. The proportion of stems in the highest quality A (stem quality classes) reached a low percentage, i.e. 12% in beech, 28% in spruce and 13% in fir out of the number of evaluated trees. The percentage of the highest quality log classes ...
Growth of Virgin Forests in the Southern Carpathians
The Journal "Agriculture and Forestry", 2016
In the beginning, all forests were represented by natural virgin forest stands. These kinds of ecosystems stand for a model representation for the managed forests. The research area is situated in Western Romanian Carpathians. To understand the functioning baseline principles of the virgin forests the radial growth of beech in relation to breast height diameter (DBH) was studied. The experimental growth distribution was determined using Beta, Gamma and Weibull theoretical frequencies functions. For the dendrochronological series, 36 samples were used. The average time span is 361 years with a mean growth of 0,999 and standard deviation (SD) of 0,482. The pointer years of this dendrochronological series were determined and the radial growths were correlated with climatic data such as temperatures and precipitations. Once the trees' volumes determined, it has been concluded that the virgin beech stands have high eco-productive characteristics (6,33 m 3 • year-1 •ha-1) , despite the age and climatic influences.
Land
The present study analysed how growth of the Norway spruce (Picea abies (L.) H.Karst.) is influenced by site conditions throughout the Eastern and Southern Romanian Carpathians. In order to achieve the aim and the objectives stated in the present study, the volume of spruce stands was taken into account and grouped into six transects, both in the north–south direction in the Southern Carpathians and in the east–west direction in the Eastern Carpathians. We used data that were extracted from the forest management plans of the areas, carried out during the period of 1980–2005. For the Eastern Carpathians, the results revealed that at the same altitudes (700–1000 m), the volumes were higher on the eastern cline than on the western. In the case of the Southern Carpathians, for altitudes between 1300 and 1600 m, the volume of trees in the southern cline was greater than that of the trees in the northern cline. It was also found that the pure spruce stands had higher growth than the mixed...
Journal of Forest Science, 2011
We analysed wood production on an example of Silver fir growth ability within site units defined in the site classification that is currently used in the Western Carpathians. It has arisen as a very important issue, since the site units have been widely used in forestry practice and, moreover, it represents one of the input variables of growth model. Research plots established for development of a yield model for Silver fir in the sixties were used. The Korf growth equation was used to model the Silver fir growth, since it showed the best fit to the data compared to other equations. The test of residual variance of the growth models and the test of regression coefficients of the growth models were employed to investigate the differences in top-height growth of Silver fir occurring on different sites. Results showed a very high variability of the top height development within the site units. Nevertheless, two main groups of sites being different from each other were recognized. Bu...
Forest Ecology and Management, 2019
There is concern in the scientific community and among forest managers about potential reductions in the provisioning of forest ecosystem services due to the loss of tree species diversity. Many studies have shown how species diversity influences forest functioning, especially productivity, but the influence of structural diversity, such as tree size heterogeneity, has received much less attention. This study focused on understanding the relationship between stand productivity and several structural characteristics of spruce-fir-beech mountain forest stands in Europe. We used a dataset of 89 long-term plots in spruce-fir-beech forests distributed along the European mountains where the three species, Norway spruce (Picea abies (L.) Karst.), silver fir (Abies alba Mill.) and European beech (Fagus sylvatica L.), represent at least 75% of the basal area. Site-dependent conditions were accounted for in a linear mixed-effect basic model, which related the stand productivity with the morphological, climatic and pedological characteristics. The influence of tree species diversity, tree size heterogeneity, species size dominance, and species overlapping in the size distribution on stand productivity was analysed by adding variables to the basic model one by one and evaluating the change in the Akaike's Information Criterion (AIC). The variables that resulted in significant reductions in the AIC, and that were not correlated with each other, were used to build a model to estimate stand productivity. The model showed that in spruce-fir-beech mixed mountain forests (i) when Norway spruce, silver fir and European beech are evenly present within the size distribution (high evenness) the productivity decreases, (ii) the stand productivity increases when the diameter distribution is skewed to the right (higher numbers of smaller individuals), (iii) the stand productivity increases as the proportion of basal area that is spruce increases, and (iv) stand productivity increases with the variability in diameter. We discuss the implications of our results for the management of spruce-fir-beech mountain forest in Europe and for preserving and increasing the stand productivity of these mixed forests.
Predictors of Wood Quality of Trees in Primary Forests in the Southern Carpathians
The Journal "Agriculture and Forestry"
Functional mechanisms in primary forests can help us discover structural models that can be applied to managed forests. Wood quality is important in silviculture because it influences timber price. Using the structure and tree form of primary forests in the Southern Carpathians as a model, our research objectives were to determine the relationships between wood quality and factors such as coenotic position of trees, the ratio of diameter at breast height (DBH) to tree height, and tree slenderness. Wood quality was strongly related to the coenotic position of trees (r = 0.89*-0.99***); suppressed (or dominant) trees had higher quality wood than dominant (or suppressed) trees. Wood quality and slenderness were also highly correlated (r = 0.56-0.95***) in most plots-the more slender the tree, the lower its wood quality. We found that trees with the highest quality wood were in the 30-100 cm DBH range. Therefore, DBH is a reliable predictor of wood quality for uneven-aged forests, providing quick results with little effort.
Romanian legal management rules limit wood production in Norway spruce and beech forests
Forest Ecosystems
Background: The quantitative impact of forest management on forests' wood resource was evaluated for Picea and Fagus mixed forests. The effects on the productivity of tendering operations, thinnings and rotation length have seldom been directly quantified on landscape scale. Methods: Two sites of similar fertility but subject to contrasted forest management were studied with detailed inventories: one in Germany, the other in Romania, and compared with the respective national forest inventories. In Romania, regulations impose very long rotations, low thinnings and a period of no-cut before harvest. In contrast, tending and thinnings are frequent and intense in Germany. Harvests start much earlier and must avoid clear cutting but maintain a permanent forest cover with natural regeneration. While Germany has an average annual wood increment representative for Central Europe, Romania represents the average for Eastern Europe. Results: The lack of tending and thinning in the Romanian site resulted in twice as many trees per hectare as in the German site for the same age. The productivity in Romanian production forests was 20 % lower than in Germany despite a similar fertility. The results were supported by the data from the national forest inventory of each country, which confirmed that the same differential exists at country scale. Furthermore, provided the difference in rotation length, two crops are harvested in Germany when only one is harvested in Romania. The losses of production due to a lower level of management in Romania where estimated to reach 12.8 million m 3 .y-1 in regular mountain production forests, and to 15 million m 3 .y-1 if managed protection forest is included. Conclusions: The productivity of Picea and Fagus mountain forests in Romania is severely depressed by the lack of tending and thinning, by overly long rotations and the existence of a 25-years no-cut period prior to harvest. The average standing volume in Germany was 50 % lower than in Romania, but the higher harvesting rate resulted in more than doubling wood production. Considering the mitigation effects of climate change by forests, it emerges that the increase in standing volume of forests in Romania is smaller than the additional harvest in Germany which serves fossil fuel substitution.
European Journal of Wood and Wood Products, 2016
The purpose of this study was to increase knowledge of the variability of wood density and annual growth of Norway spruce growing in the Ukrainian Carpathians. The material consisted of 21 trees which were cut between 600 m and 1200 m asl from southwest and northeast expositions of the mountain Dovshka. The ovendry and relative wood density increased from the bottom (630 m asl) to the top (1190 m asl) of the mountain and was related to increasing number of tree rings in 1 cm, whereas the width of annual rings decreased expressively. Three significant categories of altitude (forest types) of Norway spruce timbers were estimated for the mountain forest stands. The highest average ovendry wood density (413 kg m-3) and number of tree rings in 1 cm (17.1) were characterized by spruce trees growing at the wet rocky bilberry spruce forest (above 1000 m asl). Wood density and annual growth are two variables which were significantly correlated with each other and the altitude (R = 0.5-0.6).
Forest Ecology and Management, 2006
Dynamics in volume growth efficiency of regenerating trees in different light environments were studied for the mountainous, mixed species multiaged forests in the Carpathian Mountains of Romania. The primary species in these mixtures were silver fir (Abies alba Mill.), European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) Karst). Leaf area-sapwood area relationships were developed for seedlings/ saplings of each species. Height and diameter growth were measured and used to compute average annual stem volume growth of each tree. Percentage of above canopy light (PACL) and stand basal area were used as surrogates for the available growing space of each seedling/sapling. For all three species, volume growth of regenerating trees increased exponentially with leaf area. Conversely, growth efficiency followed a saturating increasing trend along the range in tree leaf area. Generally, growth efficiency increased with light and decreased with basal area. The fir was the most efficient in dense stands, while beech and spruce were less efficient and followed similar trends with basal area. In open, conifers showed similar efficiency rates while beech was less efficient. For beech, the lower rates in open compared to conifers and the similar rates in dense stands compared to spruce may be an artifact of using only stem volume to compute growth efficiency.
Glasnik ?umarskog fakulteta, 2002
Considering the great significance of volume increment in forestry, it is understandable that there are numerous methods of its assessment. However, all these methods have some disadvantages, either the accuracy of the obtained results, too large scope of works of forest inventory (economicity), or the restriction only to stands of certain silvicultural type. To make the method of stand volume increment more economic and simplified, we defined regression models for volume increment percentage assessment in fir, spruce, Austrian pine and Scots pine stands in Serbia. Empirical data were fitted by four regression models for each tree species. The criteria for the final selection of models for the determination of volume increment percentage were the relevant statistic parameters of regression and correlation analysis, and the degree of concordance of "real" and fitted ("table") values of volume increment percentage. The selected models for the above tree species are...