Abies

Study of lipophilic and hydrophilic extractives in heartwood, sapwood and knots of 39 industrially important conifer species: 14 pines (Pinus), 7 spruces (Picea), 9 firs (Abies), 5 larches (Larix), 3 hemlocks (Tsuga) and Douglas-fir (Pseudotsuga).

The wood samples were sequentially extracted, and the amount and composition of resin acids, fatty acids, sterols, steryl esters, acylglycerols, juvabiones, lignans, oligolignans, flavonoids and stilbenes were analysed by gas chromatography (GC) and GC-mass spectrometry.

In the last 20-30 years in the forests in the Republic of Macedonia has been noted increasing presence of the fir. There are a number of factors that condition the spread of the fir, mainly the higher protection from the harmful effects of the anthropo-zoogenic factor, and changes in the environmental conditions. The spread of the fir is most intense in the zone of the beech forest region, but expansion is observed in the higher oak regions, too. This occurrence is a result of two main reasons: i) spread of the fir regarding natural regeneration; ii) spread of the fir by sowing fir seed in the beech and oak forest communities. The fir as a shade-tolerant species is the one which can survive and thrive as an understory of beech forests and it is capable to have a long time to rest awaiting the favourable moment for expansion in height. In the struggle for light in natural successive processes the fir manages to overcome the beech, which is confirmed by the fact that in high density beech forests the fir's offspring successfully adapt to site conditions. Thus, it is evident the phytocoenological destructing role of the fir particularly in the beech forest communities in the Republic of Macedonia. In addition, the plant diversity in pure fir forests is poorer then in mixed fir forests. Confirmation of this finding are the data obtained from the management plans which shows the changing of the structure of the forests by composition and volume in favour of the fir.

By 432 B.C., according to Thucydides' cursory account (1.57.2-3), the alliance of Athens with Perdikkas's internal enemies had precipitated a deterioration in the formerly amiable Atheno-Macedonian relations. The present paper focuses on this peculiar termination of goodwill with Perdikkas through the lens of timber commerce. The author maintains that Perdikkas effectively opposed Athenian imperialism by restricting his monopolistic supply of silver fir (Abies alba), since timber from this Abies species was an unrivaled resource for shipbuilding and, according to archaeobotanical data, was available only in Macedon. As a result, the shift of allegiance recorded by Thucydides emerges as part of an elaborate Athenian strategy that, among other advantages, would also facilitate access to invaluable shipbuilding resources.

In the last 20-30 years in the forests in the Republic of Macedonia has been noted increasing presence of the fir. There are a number of factors that condition the spread of the fir, mainly the higher protection from the harmful effects of the anthropo-zoogenic factor, and changes in the environmental conditions. The spread of the fir is most intense in the zone of the beech forest region, but expansion is observed in the higher oak regions, too. This occurrence is a result of two main reasons: i) spread of the fir regarding natural regeneration; ii) spread of the fir by sowing fir seed in the beech and oak forest communities. The fir as a shade-tolerant species is the one which can survive and thrive as an understory of beech forests and it is capable to have a long time to rest awaiting the favourable moment for expansion in height. In the struggle for light in natural successive processes the fir manages to overcome the beech, which is confirmed by the fact that in high density beech forests the fir's offspring successfully adapt to site conditions. Thus, it is evident the phytocoenological destructing role of the fir particularly in the beech forest communities in the Republic of Macedonia. In addition, the plant diversity in pure fir forests is poorer then in mixed fir forests. Confirmation of this finding are the data obtained from the management plans which shows the changing of the structure of the forests by composition and volume in favour of the fir.

In this scientific paper are observed data related to research conducted of the phytocoenological characteristics of the territory of the National Park Mavrovo in the Republic of Macedonia. Therefore, visited and explored were the mountain massifs: Shar Planina, Korab and Bistra. Within the completed surveys, the standard phytocoenological method of Braun-Blanquet was used. On the teritory of the Park, authors noted and identified 28 forest communities (19% of the 148 identified plant communities in the Republic of Macedonia), i.e. 4 coastal floodplain (riparian) forest communities, 18 typical forest communities and 6 degraded-coppice forests. Coppice forests until now have not been guided in the literature. Also were disclosed forests with virgin forest's character. In addition to natural forest communities, listed are artificial forest stands. Likewise, were discovered new data of certain phytocoenological phenomena, as in the Park, and in Macedonia. New insights arising from this research are particularly important, taking into account the rapid progress of studies on vegetation in Europe (creating ecological networks) and thus solve the important forest ecosystem problems. Extensive scientific work will undoubtedly lead to the creation of a solid and relevant base of phytocoenological data that will provide the conditions for protection of significant forest communities in the Park and thus in Macedonia.

Plant species living in the understory increase carbon (C) allocation toward leaf production for maximizing light capture at the expense of roots and stems, with negative consequences for the whole-plant hydraulic conductance. Moreover, under some conditions, the high atmospheric evaporative demand occurring in Mediterranean areas may be not well buffered by the canopy, which might be the case for relict conifer Abies pinsapo Boiss. growing in the forest understory. We hypothesized that acclimation to combined understory shade and high atmospheric dryness can be achieved through the adjustment of water losses to cope with the restriction in water transport. The results reveal high structural plasticity in A. pinsapo that allows light harvesting of this species to maximize light capture in the forest understory, and maintain a positive C balance under low light conditions. However, growth in the understory resulted in reduced leaf-specific conductivity, up to approximately four to fi...

The volatile composition of Abies alba Mill. seeds and cone scales has been studied, leading to the determination of 90 volatile constituents. The major component of the seed essential oil was (-)-limonene (about 70%), while that of the cone scale oil was a-pinene (57%). Monoterpene hydrocarbons were predominant in both oils, but the quantitative and qualitative composition of the volatile compounds was specific for each part of the tree.

Altitudinal timberlines are thought to move upward by global warming, a crucial topic in ecology. Tall tree species (the conifer Abies mariesii and the deciduous broad-leaved Betula ermanii) dominate the sub-alpine zone between 1600 and 2500 m a.s.l., the timberline, on Mount Norikura in central Japan. Dwarf pine Pinus pumila dominates above the timberline to near the summit (3026 m a.s.l.). This study evaluated how the timberline formed on Mount Norikura by examining altitudinal changes in stand structure and dynamics around the timberline. One hundred and twenty-five plots of 10 m × 10 m were established around the timberline (2350-2600 m a.s.l.). Trunk diameter growth rate during 6 years was examined for A. mariesii, B. ermanii and P. pumila. Mortality during this period and mechanical damage scars on the trunks and branches due to strong wind and snow were examined for A. mariesii only. The density, maximum trunk height and diameter of A. mariesii in plots decreased with altitud...

The fragments of Abies guatemalensis forests in Western Guatemala are the reservoirs of plant species that have been poorly documented, missing the opportunity to expand the knowledge of the local flora and its use in conservation planning. To assess this, a floristic study was done in areas between 2 950-3 360masl in Western Guatemala between 2010-2011. Ten locations were sampled: in each a 500m2 plot was surveyed, and plants were classified in four strata by plant height (0.05-30m). A total of 119 species, 92 genera and 50 families in four divisions were found. The families with more species were Asteraceae, Poaceae, Rosaceae, Lamiaceae, Apiaceae and Solanaceae, and the most abundant genera were Salvia, Alchemilla and Bidens. The number of species found by strata was: 33 (low herbaceous), 49 (high herbaceous), 30 (shrubs) and seven in the tree strata. Regarding geographical distribution, the biggest species group detected was from central Mexico to Central America with 67%, which ...

Significant increases in tree mortality due to drought-induced physiological stress have been documented worldwide. This trend is likely to continue with increased frequency and severity of extreme drought events in the future. Therefore, understanding the factors that influence variability in drought responses among trees will be critical to predicting ecosystem responses to climate change and developing effective management actions. In this study, we used hierarchical mixed-effects models to analyze drought responses of Pseudotsuga menziesii in 20 unmanaged forests stands across a broad range of environmental conditions in northeastern Washington, USA. We aimed to 1) identify the biotic and abiotic attributes most closely associated with the responses of individual trees to drought and 2) quantify the variability in drought responses at different spatial scales. We found that growth rates and competition for resources significantly affected resistance to a severe drought event in ...

Leaves growing in the forest understory usually present a decreased mesophyll conductance (gm) and photosynthetic capacity. The role of leaf anatomy in determining the variability in gm among species is known, but there is a lack of information on how the acclimation of gm to shade conditions is driven by changes in leaf anatomy. Within this context, we demonstrated that Abies pinsapo Boiss. experienced profound modifications in needle anatomy to drastic changes in light availability that ultimately led to differential photosynthetic performance between trees grown in the open field and in the forest understory. In contrast to A. pinsapo, its congeneric Abies alba Mill. did not show differences either in needle anatomy or in photosynthetic parameters between trees grown in the open field and in the forest understory. The increased gm values found in trees of A. pinsapo grown in the open field can be explained by occurrence of stomata at both needle sides (amphistomatous needles), in...

Genetic diversity and fine-scale population structure in the lichen-forming ascomycete Xanthoria parietina was investigated using sequence variation in part of the intergenic spacer (IGS) and the complete internal transcribed spacer (ITS) regions of the nuclear ribosomal DNA. Sampling included 213 and 225 individuals, respectively, from seven populations in two different habitats, bark and rock, on the island Storfosna off the central west coast of Norway. Both markers revealed significant variation and a total of 10 IGS and 16 ITS haplotypes were found. There were no signs of significant positive spatial autocorrelation at any spatial size class down to 10% of transect length, nor did we find significant deviations from neutrality or signs of historical population expansion. Analysis of molecular variance (amova) indicated that most of the genetic variance observed was within populations, but when populations were grouped according to habitat, more than a quarter of the variance was explained among groups. Pairwise comparisons of populations (FST, exact tests of population differentiation) revealed significant differentiation between populations in different habitats (on bark or rock), but not between populations in the same habitat. Haplotype networks show that internal and presumably old haplotypes are shared between habitats, whereas terminal haplotypes tend to be unique to a habitat, mostly bark. We interpret the observed pattern to mean that there is no evidence of restricted gene flow between populations in the same habitat at the present spatial scale (interpopulation distances one or a few kilometres). On the other hand, differentiation between habitats is considerable, which we attribute to restricted gene flow between habitats (habitat isolation). Evidence suggests that the observed differentiation did not evolve locally. Estimates of divergence time between populations in the respective habitats indicate that an ancestral population started to diverge at least 34 000 years ago but probably much further back in time.