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Lower Cretaceous belemnites (including J/K boundary interval) in the NW Tethys, biostratigraphy, palaeobiogeography and palaeoecology
Vaňková, Lucie ; Košťák, Martin (advisor) ; Michalík, Jozef (referee) ; Fozy, István (referee)
This thesis deals with the belemnite fauna from the Outer Western Carpathians Klippen, its systematic classification, stratigraphical and palaeogeographical evaluation. The palaeontological/palaeobiological approach, together with isotope analyses, including of carbon and oxygen stable isotopes and of strontium isotopes, enabled an integrated investigation of the palaeoecological conditions during the Jurassic/Cretaceous (J/K) boundary interval and the Early Cretaceous age. The Tethyan belemnites are not intensively studied in detail in the J/K interval, as they occur rather rarely in the sections, and/or sedimentary conditions were not suitable for their preservation. Therefore, belemnites are described only from a few sites in the Mediterranean Province. On the basis of recent research, the stratigraphic range of several species previously considered to be from the Tithonian age was extended to the earliest Cretaceous. By contrast, the Lower Cretaceous belemnites (since the late Berriasian) are more abundant. In the classical areas of the Tethyan Realm, it is possible to study the Lower Cretaceous belemnites in great detail and, according to their higher abundance, to determine an individual assemblage corresponding to stratigraphical intervals. Their occurrence is also an important basement for...
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Hodnocení ekologických limitů a zdravotního stavu buku lesního (Fagus sylvatica) v oblasti vnějších západních Karpat
Mikulenčák, Josef
European beech is an important and irreplaceable economic tree species in the forests of the Czech Republic. This thesis was created in thearea of Outer Western Carpathians, and it focuses on evaluation of ecological limits and the health condition of beech on network-based research plots from 2th vegetation tier (280 m) after 8th vegetation tier on the Lysá Mountain (1323 m). In each research area, basic dendrometry characteristics were measured and evaluated biotic and abiotic damage was evaluated. The results indicate that optimal growth conditions for beech are in the 4th vegetation tier. In other vegetation tiers, beech is more limited by abiotic factors than by biotic factors. In the 2th and 3th vegetation tier, the growth of beech is limited by frequent occurrence of drought. In contrast in higher vegetation tiers (6th, 7th, and 8th), frost, glaze and shorter growing period associated with lower average temperatures have the highest impact on the growth of beech. High vitality, wide ecological valence, a limited amount of biotic factors which damage beech and the ability to change the growth symptoms in individual vegetation tiers made beech into one of the main edificators of vegetation tires.
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