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Sudeteny Mts. are a region where the level of industrial air pollution was very high due to brown coal combustion. In this paper I presents the assessments concerning the fir stand quality class and crown vitality.The study were carried out between 1999 and 2001 and supplemented with studies made in 1997 and 2005. My conclusions are based on measurements of 3529 fir trees representing 481 populations of this species in different parts of the Sudety Mts. The stand quality class of the fir in the Sudety Mts. are better than expected but about 0,5 degree lower than in the Carpathians. Our results confirm the reports concerning the strong and very strong damage of fir crowns in the Sudety Mts. in the 1990’s. It was calculated that the average fir in the Sudety Mts. stands has a primary crown with a length that is approximately 19% of the total tree height and which is damaged in approximately 36%. At approximately 23% of the total height the average fir develops a regeneration crown. An additional factor which contributed to fir damage was their frequent presence in thinned stands. In these places the process of crown reconstruction from a wide to a denser is observed. In the recent years the level of industrial pollution in the Sudety Mts. has been strongly reduced. This particularly concerns sulphur oxides. This has contributed to the improvement of the crown health of the studied species, but the crown regeneration is slower than the trunk diameter increment. The crown damages have so far been proportional to the altitude. Trees which grow in stands located in lower areas have healthier crowns. Trees which grow in broken canopy and on hilltops are more vulnerable to the impact of pollution carried by wind and fog. The severe damage to the top parts of the crown has a negative effect on the cone crop of the fir.
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Kaspazy - egzekutorzy smierci komorki

100%
Wszechświat
|
2010
|
tom 111
|
nr 10-12
280-284
In this paper, is presented data on the abundance and age structure of natural regeneration of silver fir in permanent plots in Sudety Mts. In the studied plots the abundance of fir seedlings is usually markedly lower than in the well-regenerating Carpathian forest stands. The major reason for this is the lower contribution of fir trees to forest stands in the Sudety Mts. as compared with the Carpathians. In most plots the process of regeneration is long and extended over many years. Largest numbers of seedlings developed in years of good fir cone crops. An important role in the process of natural regeneration of Abies alba in the Sudety Mts. are played by type of site, kind of humus and herb layer density. Most of the studied forest stands in the Sudety are not dense, so the herb layer is well-developed, that strongly restrain fir regeneration especially in fartile soils.
Japanese larch (Larix kaempferi Sarg.) is one of the most frequent exotic species in Polish woodlands. The basic object of research comprised 60 stands of the studied species, located mainly in the northern and western parts of Poland. The growth results for the studied species, evaluated on the basis of the average height (hg55), were compared with data describing the local climate and the stand location within the botanical and climatic zoning. The results confirm the opinion that the Japanese larch prefers a climate of maritime character and generally shows high degree of flexibility regarding its climatic requirements (very large differences between the growth conditions in the studied area and the country of origin). The dependence between the growth results and precipitation is however lower than expected. The most interesting results include the relatively clear connection between the height of the larch stands and the Degórski’s (1984) ‘floristic’ ‘K’ (continentality) index.
Heterobasidion annosum (Fr.) Bref. is a fungal pathogen causing root rot – one of the most economically important diseases in coniferous stands in Europe, Asia and North America. A major objective of this study was to determine if the offspring of self-sown trees from natural regeneration in old foci of root rot is more resistant to infection by this pathogen than the offspring of plus trees. In experiments conducted in the greenhouse above 700 seedlings grown from seeds collected from 60 trees in 6 old foci of the disease (research plots) and 480 seedlings grown from seeds collected in 4 seed orchards were used. The pathogen was represented by 7 different fungal strains. Plus trees, whose grafts are used to establish seed orchards, were the selected elite of forest trees, but their offspring after inoculation with H. annosum had significantly worse results than the seedlings developed from the seeds collected in old foci of the disease (research plots). The greatest differences were observed in seedling dry weight. In inoculated seedlings from seed orchards it was 14% lower than in the control, while the dry weight of inoculated seedlings from research plots did not differ significantly from that of non-inoculated seedlings.
The purpose of this study was to determine the basic physico-chemical properties of soil in silver fir stands with different stage of natural regeneration. The investigations were carried out in south-west part of Poland – in the Sudety Mountains. From 854 silver fir stands, 40 testing sites, varying in terms of habitat conditions and degree of natural regeneration, were selected. Soil samples were collected from litter (organic horizon – O) with a thickness of 7–15 cm and from mineral A horizon lying up to 20 cm below the organic horizon and were then analysed for pH, EC, C org., total N, exchangeable cations (Ca, Mg, K, Na, H and Al), soluble Mn, Fe, Zn and Pb as well as particle size distribution (samples from A horizon). The analysed soil samples are characterized by very high acidity and low content of bases. According to the performed statistical tests, none of the factors analysed within the samples tested has a significant impact on the natural regeneration of silver fir. The only dependence between potassium content in soil and the regeneration of silver fir in the Sudety Mountains is close to statistically significance.
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