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The paper presents a comparative analysis of wood calorific value of grand fir (Abies grandis Lindl.), originating from four stands of the southern Poland. The research material were the samples, collected from the trunks of 30 trees in each stand. The samples were divided into sections, each containing five annual increments. Then each section was measured: annual ring width and the relative wood density, which was converted to dry wood density, taking the total volumetric shrinkage of 11%. It was assumed that the calorific value of 1 kg dry wood of grand fir is 20.15 MJ. On the basis on the analysis it was found that the average calorific value of 1 m3 of grand fir wood was 8021 MJ. It was shown, that a significantly higher calorific value was obtained by the combustion of 1 m3 wood of giant fir trees, growing on the poorer soil in comparison to the more fertile soils. Statistical analysis also showed that with increasing age of the trees the calorific value of 1 m3 grand fir wood increases significantly.
The paper presents the results of investigations into the variability of certain features of the wood macrostructure, such as the width of the annual ring, the share of late wood, and the relative density of the wood of grand fir, growing in four stands in southern Poland. The trees under investigation were 30-35 years old. The research material consisted of incremental cores sampled from trial trees with the use of a Pressler borer. The examined wood features were analysed in sections, each one comprising five annual rings. The rings were given numbers, sorted in an ascending order from the trunk circumference. The mean values of the analysed features were as follows: the annual ring width – 4.38 mm, the share of late wood - 35.39%, the relative wood density – 0.354g·cm-3. It was established that the wood of grand firs growing on less fertile soils had significantly narrower annual rings and higher wood density than those on more fertile soils.
The paper gives a survey of biodiversity of planted grand fir (Abies grandis) stands in Rogów Arboretum on the background of environmental data compared to those of its natural distribution. Some information concerns studies on grand fir plantations in Europe and their influence on chosen components of the ecosystem. During the study, 63 taxa of vascular plants, mosses and liverworts, 46 taxa of fungi and 110 of invertebrates were found.
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