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31.
The Swiss stone Pine (Pinus cembra L.) is an alpine species, fairly commonly occurring in the Alps and the Carpathians, close to the timberline. Natural sites of the Swiss stone pine in Poland are found exclusively in the Tatra Mountains, within the area of the Tatra National Park (TNP). In 2017, the health status of the needles of P. cembra was determined and their mycological analysis was carried out. As a result, 11 species of fungi were isolated from the needles showing disease symptoms, manifested by various shades of discoloration. The most frequently observed species was Fusarium oxysporum. It probably does not bring on disease symptoms, but may affect the development of other frequently isolated species (such as Sydowia polyspora, Lophodermium sp. and Lophodermium conigenum) that are pathogenic to Pinus spp. 相似文献
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Wiesław Wiśniewolski Janusz Górczyński Wiesław Madry 《Aquatic Sciences - Research Across Boundaries》1989,51(3):249-259
Width of the first ray of the pectoral fin has been measured in two places for 154 young and 89 adult wels. Statistical relationships between the above characters and fish length as well as its maturity and sex have been proved. Three models of discriminant function for identification of adult fish sex have been derived and verified. The accuracy of sex separation has been 89,5% in a standard sample of wels, and 90,6% in a routine sample, after an adjustment in the procedure. 相似文献
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The mountain slopes and river channels of the temperate zone and of the humid tropics are modelled by various types of extreme rainfall. In the Flysch Carpathians the leading role is played by continuous rains causing floods and landslides, rainy seasons (wet years) mobilizing deep landslides and, to a smaller degree by local downpours. In the Darjeeling Himalaya with young relief and uplift tendency, the main influence on modelling the mountain slopes and river channels have been the extreme continuous rains separated by several decades of normal rainy season, playing the preparatory or relaxation role with simultaneous transformation of slopes and river channels. In both cases human impact has caused the acceleration of runoff and mobilization of sediment. The higher extremes of precipitation and steep slopes in the humid tropics are balanced (to some extent) in temperate zones by the lower infiltration rates and lower thresholds of mass mobility on the gentle slopes originated in the periglacial environment. 相似文献
37.
Ewa Jasińska 《Estuaries and Coasts》1993,16(1):53-67
The hydrodynamics of saline water in Polish estuaries are addressed in this paper. The phenomena are described on the basis of field data from several types of estuaries along the Polish Baltic Coast. Field measurements were made to reveal and to characterize the physical processes in these estuaries; this information was then used for analytic testing and verification of mathematical models. The results demonstrate the unsteady and changeable nature of both the flow conditions and the motion of salt water in tideless estuaries. The magnitudes and directions of the barotropic and baroclinic horizontal pressure gradients have a marked influence on the flow characteristics and motion of salt water in these tideless estuaries. 相似文献
38.
A. Piestrzyński 《Mineralium Deposita》1990,25(2):146-151
The Kupferschiefer in Poland has an increased U content. The facies high in organic matter are significantly enriched in U. The maximum values of U are mostly in the lower part of the Kupferschiefer sequence. The mean (x) U content in the Kupferschiefer from the Lubin-Sieroszowice district is 61.5 ppm and from the rest of the Polish Zechstein basin is about 26 ppm. Thorium occurs only in small quantities (x) = 1.5 and 5 ppm respectively). The high variance of U and Th in the Kupferschiefer is due to multistage diagenetic processes. The main U carrier is thucholite. The investigated thucholite showed a Th-content below 0.36 ppm. Thucholite with uraninite exolutions showed small (up to 1.0 wt.%) admixtures of U and thucholite without microscopically visible exsolutions (up to 37.85 wt.% U). The phosphates showed significant amounts of U (up to 0.24 wt.). The U content in the Kupferschiefer is significantly lower than in black shales from other part of the world. Uranium in the Lubin district is not economic. 相似文献
39.
Wojciech Stopiński Gienadiy A. Sobolev Aleksandr W. Ponomaryov Vladimir Los 《Pure and Applied Geophysics》1991,136(1):49-58
Making measurements of electric resistivity at 16 s intervals, the authors noticed fast changes of this parameter prior to the occurrence of the main fracture. The changes are superposed on bay pulsations of increasing amplitude and decreasing period. This finding opens prospects for a wider use of an electric resistivity method and proves the high quality of automatic instruments, in particular their high resolution. It also gives evidence for the occurrence of short-period precursors in the fracture zone while the main fracture is being formed. 相似文献
40.
Polish forest ecosystems: The influence of changes in the economic system on the carbon balance 总被引:1,自引:0,他引:1
In order to study the effects of a change in the economic system on carbon balance at a national scale, a balance of the carbon influx and effluxes was prepared for forest ecosystems in Poland for 1988, and was repeated for 1990. The year 1988 was the first year of drastic economic changes (and severe crises) in Poland. Two entirely different approaches were used to estimate the carbon influx into a forest ecosystem. The forest inventory approach was based on data from conventional measurements of merchantable timber in forests, whereas the carbon flux and allocation approach was based on the estimate of net photosynthetic productivity of forest ecosystems to calculate the carbon influx. Results from both approaches were within the range 1.17 to 5.77t C/ha/yr which most likely defined lower and upper limits for the carbon influx into forest ecosystems in Poland. On the national scale, the carbon influx into Polish forest ecosystems was estimated by the forest inventory approach to be about 12.8 Mt C/yr. This result was similar for both years. Efflux of carbon from Polish forest ecosystems resulted almost entirely from the decay of logging residues. The efflux in 1990 (3.82 Mt C/yr) was about 26% lower than that in 1988. Storage of the carbon in Polish forest ecosystems (including an estimate of the carbon pool in forest soils) was 1.8% greater in 1990 (2518 Mt C) than in 1988, when it equalled 2473 Mt C. 相似文献