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The main aim of this study was to describe the variation between the populations of the dwarf mountain pine Pinus mugo Turra based on the morphological and anatomical traits of their needles, and to investigate the relationship between the observed variation and environmental conditions (altitude and substrate).Two-year-old needles were collected from 180 individuals of six populations of P. mugo growing in the Tatra Mts. Two populations were classified as dense, located at 1360–1450 m altitude, and the remaining four formed loose clusters and were situated at 1500–1650 m altitude. Four of the populations are growing on granite and two on a limestone substrate. The natural variation of 10 morpho-anatomical and 3 synthetic needle traits was measured. In addition to descriptive statistics, the analyses of variance (ANOVA) with a Tukey test and principal component analysis were computed. We also estimated Pearson correlation coefficients for the examined needle traits and altitude as well as substrate. Our results indicate that the P. mugo populations differ significantly with regard to the investigated traits for which the Trzydniowiański Wierch population was the most distinct. The observed pattern of variability is largely caused by differences in stomatal traits and these features are positive correlated with altitude. Additionally, populations growing on granite have larger values for most of the examined traits compared to populations growing on limestone.
The study presents a method of planning species composition of forest stands in mountain areas on the example of Beskid Niski Mts. (south−eastern Poland). The focus was on the species composition of forest stands growing in different conditions, taking into account the type of forest habitat and terrain characteristics: altitude, exposition and slope. The research was based on data stored in the Information System of the State Forests. We used modified growth model for data processing and calculation of site index for the forests older than 60 years. The Beskid Niski Mts. are covered mostly by European beech (33.8%), silver fir (28.3%) and Scots pine (18.9%). Taking into account exclusively the productive capacity of individual forest stands, fir and spruce would be the most desirable species in analysed region. The Beskid Niski Mts. are characterized by a very small diversity of the habitat with domination of mountain fresh deciduous forest (LGśw, 92.1% of the area). We divided analysed region into four altitudinal zones that vary greatly in fraction of afforested area. Beech dominates in all zones and its share increases from the foothills to montane zone (fig. 5). Basing on a digital terrain model, the areal share of 10 landforms was determined for each stand and altitudinal zone (fig. 8). This enabled more detailed planning of species composition. However, it required the adoption of six specific assumptions including the need to maintain a suitable proportion of all tree species growing in the mountains, specifically the main forest tree species: spruce, fir and beech. The 5−stage project (preliminary, historical, current, planning, verification stages) consisting of planning species composition uses, in stage 4, detailed information on landforms. The project assumes that the fragments of forests where trees are expected to grow fast will be earmarked for endangered species. The model sees the need of planting the weaker tree species to be present in the forest ecosystems of the Beskid Niski. The proposed project will enable foresters−practitioners to plan the forest species composition for each of the forest districts in the Beskid Niski quickly. Such a programme might also be an integral part of the growth model of forests useful for forecasting and increasing timber resources.
Since 1970 two meadow experiments were carried out in the IMUZ Experimental Station in Jaworki to study the influence of longterm various fertilization on the properties of the meadow ecosystem. The respective investigation presented the effects of different fertilization and application of NPK (I - without fertilization, II - PK, III - PKN - 60, IV - N-60, V - PKN-120, VI - N-120, VII - PKN-180, VIII - N-180, IX - PKN-240, X - N-240) on grassland yield. The most constant yield - over a long period of time - was obtained in full NPK and PK fertilization in the I experiment on the 600 m a.s.l. A significant yield decrease was observed after 15 and 20 years of the experiment (tab. 1). After this time a meadow renovation should be done. When pure nitrogen was applied the decrease in yield was observed after 10 years. In the II experiment (800 m a.s.l.) the decrease in yield was notified after 5 years of using, particularly on fields where only nitrogen was applied. This means that these areas are less useful for cultivating meadows.
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