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The “Źródła Rzeki Łyny im. prof. R. Kobendzy” nature reserve was established in 1959 and occupies the area of 120.54 ha. The paper describes fl ora and plant communities of this reserve. In total 409 vascular plant taxa from 70 families and 235 genera were inventoried, including 24 species which are under legal protection, as well as rare plants and those which are threatened in this region. Nine plant communities were identifi ed within the boundaries of the reserve of which three were forest autogenic or autogenic-like communities (Ribeso nigri-Alnetum, Stellario nemorum-Alnetum glutinosae, Tilio cordatae- -Carpinetum betuli), three were forest anthropogenic communities with Pinus sylvestris, Betula pendula, Larix decidua and Larix ×eurolepis and Picea abies on lime-oak-hornbeam forest sites, as well as three non-forest communities (Salicetum pentandro-cinereae, Phragmitetum australis and a meadow community from the Molinio-Arrhenatheretea class). The highest natural value was determined in very well developed phytocoenoses of Stellario nemorum-Alnetum glutinosae (the rarest in the reserve), in Ribeso nigri-Alnetum and Tilio cordatae-Carpinetum betuli, as well as meadow communities from the Molinio-Arrhenatheretea class. They provide sanctuary for many species of rare and threatened plants.
The Turkey oak (Quercus cerris L.) is one of the least known species of trees of alien origin introduced to forests in Poland. Its natural geographical range embraces southern Europe and Asia Minor. It started to be grown on the Polish lands in 1813, planted primarily in parks and gardens, mostly in the western part of the country. On the basis of the present authors’ own field search, the literature, and unpublished data, it was possible to collect information about 22 places of occurrence of the Turkey oak in the woodland areas of Poland. A map of the distribution of this species is presented and the characteristics of its most extensive localities in forests are given. The oldest and most robust tree stands comprising Quercus cerris, planted in the fertile riverside habitats of the Oder river valley, have reached the age of 130-150 years. In those conditions the Turkey oak attains a height of 37 m and a breast-height diameter of up to 120 cm. Because of frequent frost damage and a low quality of trunks, it is of no productive significance in forestry. Even so, it is an interesting example of an alien oak species which, like the well-known  Q. rubra, shows the ability to expand in a woodland environment.
Background: Although corrosion casting has been implemented for almost five centuries, the choice of resin has a strong influence on the effectiveness of casting vessel formations. Our aim was to compare quality and quantity features of two groups of corrosion casts made using two kits: Plastogen G resin and Batson no. 17 resin. Materials and methods: Thirty corrosion casts were made of testicular arterial vessels (15 made using Plastogen G and 15 made using Batson no. 17) and their shape, colour, fragility and flexibility were evaluated. The following parameters were measured: maximal width of corrosion cast of testis, maximal length of centripetal and centrifugal arteries, diameter of testicular artery and its terminal branches. Based on these measurements, five indexes were calculated (Iq1–Iq5). Results: Generally both groups of corrosion casts demonstrated similar attributes. Only the rami tunicales minores displayed higher fragility and lower flexibility in the Plastogen G group than the Batson no. 17 group. The only observed quantitative difference was that Iq3 was significantly lower in the Plastogen G group (0.71 ± 0.01) than in Batson no. 17 group (0.79 ± 0.01; p = 0.0092). Conclusions: The two corrosion cast groups displayed similar qualitative and quantitative attributes. Batson no. 17 appears to be a good resin for three-dimensional visualisation of extra- and intratesticular arterial vessels. (Folia Morphol 2019; 78, 3: 487–493)
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