Makroskopowa charakterystyka osadów dennych jezior tatrzańskich

• Autorzy: Wieckowski K.

Warianty tytułu

EN

Macroscopic characteristics of the lacustrine deposits of the Tatra lakes

• Języki publikacji: PL

Abstrakty

EN

In the course of four successive expeditions (in the years 1974-1978) bottom samplings were carried out to withdraw a number of undisturbed core samples of the deposits of 11 Tatra lakes, in that number from the Štrbské Lake situated on the southern slopes of the Tatra Mts. (Slovakia). The sediments, the brown algal-detrital gyttjas, are similar in all the lakes studies. They contain 20 to 80 per cent organic matter, substantial amounts of vegetable macroremnants, and an unordered mixture of sand and gravel grains. Some traces of microstratification of ten occur there; they are, however, irregular and can hardly be taken as indications of a seasonal annual periodicity of the sedimentation processes. The thickness of lacustrine deposits in the Tatra lakes attain as little as 1-3 m (being 5 to 8-fold less than the values recorded for the lakes of the Poland’s lowland regions). A clear drop in the deposits thickness and of the sediments accumulation rate, with the altitude a.s.l. of the lake, is observed. This is related to the zonal character of the mountainous climate which affects the water temperature, the period the water remains under ice, intensity of biological processes, as well as physical and chemical erosion. In spite of the fact that the Štrbské Lake lies on the southern slopes of the Tatras, the nature of its lacustrine sediments (the algal-detrital gyttja) and their thickness (2.5 m) are similar to those occurring in other lakes. Their only feature is a markedly fibrous structure and a higher organic matter content (66-84 procent). In the lakes deeper than 20 m (with the exception of the lake Zadni Staw) the deposits is dual: underlying the organic matter layer of a thickness of 1-2 m are light-grey silty mineral sediments 1-1.5 m thick. They indicate that the lakes already existed in the period when the conditions typical of the periglacial climate prevailed. Meanwhile, a clear-cut boundary between the mineral and organic sediments overlaying the former, points to a very rapid and dramatic change of the climate (the warmer period). This resulted in an intense development of the organic life in the lakes and their surroundings. The results of ¹⁴C dating and palynologic analyses indicate that this must have occurred in the Alleröd. It is remarkable that in shallower lakes (less than 20 m deep), with the exception of the lake Smreczyński Staw and the Štrbské Lake, in one core sample of which some sandy sections (0.2 m) of the floor part were found, no sandy and gravel formations cound be seen, as in the other sampling sites the sampler used to hit a rocky or solid rock bottom.

• Wydawca: -
• Czasopismo: Prace i Studia Geograficzne
• Rocznik: 1984
• Tom: 05
• Opis fizyczny: s.39-54,rys.,

Twórcy

autor

Wieckowski K.