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On the Nothernmost and Southernmost Limits of European Land Snail Spatial Ranges
Křepelová, Lucie ; Juřičková, Lucie (advisor) ; Horsák, Michal (referee)
The aim of this work was to evaluate the limits of ranges of European land snail species along the north-south gradient. To work out the document it was necessary to prepare the set of digitalized maps, that enabled to create the database of ranges of the individual land snails species. Based on obtained data I tried to identify places where the northern and southern borders of species ranges are the most frequent. The landsnails' ranges are affected not only by particular life requirements of the individual species (potential limits), but also by other conditions, especially climatic, geographical and historical (truncated limits). In this work I focused on their differentiation. Above mentioned process also enabled me to track the north- south changes in species richness of the landsnails taking into consideration the truncated and potential limits. The most important natural barriers constraining that numerous of species cannot naturally widespread from the south to the north are the Scandinavian Mountains, the Alpes and the Carpathians and suprisingly also southern borders of german and polish lowlands. On the other hand, spreading of the species form the north to the south is limited only by the Alpes. I also tried to distinguish the group of species whose ranges are not influenced by these...
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Diversity of methods used for characterization of molluscan hemocytes
Jindrová, Zuzana ; Skála, Vladimír (referee) ; Horák, Petr (advisor)
Hemocytes are the main immune cells of invertebrates; therefore they can be found in molluscs, too. They differ both in morphology and function. The two generally accep- ted morphological types, granulocytes and hyalinocytes, vary in the level of phagocy- tosis and encapsulation, production of reactive oxygen species and nitrogen oxide, and presence of some enzymes. There is an array of methods by means of which hemocy- tes can be characterized. Microscopy serves particularly for study of morphology. An- tigens localized on the surface can be determined by monoclonal antibodies or lectin probes. Hemocytes can be divided on the basis of cell size and granularity using gra- dient centrifugation or flow cytometry. Production of nitrogen oxide and reactive oxy- gen species is monitored by adding appropriate substrate which changes its proper- ties after reaction with the radical. It may become fluorescent, change absorbance of the solution or form a visible precipitate. Another possibility is the use of chemilu- miniscence. The objective of hemocyte research is to explain mollusc-pathogen inter- action. 1
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Evolutionary strategy in biomineralization of mollusc shells: Micromechanical properties of shells and their relationship with the environment
Hrabánková, Iva ; Frýda, Jiří (advisor) ; Marika , Marika (referee)
This thesis deals with the micromechanical properties (microhardness and elastic modulus) of selected molluscan shell microstructures and their relationship to crystallographic textures and environment. Results of the study suggest that extremely high hydrostatic pressure has a relatively weak influence on the mechanical properties of calcitic as well as aragonitic shell layers. No statistically significant difference was found in microhardness and elastic modulus of nacre between bivalvian species living in marine and freshwater environments. On the other hand, the study reveals a statistically significant positive correlation between the micromechanical properties and thickness of aragonitic platelets forming the nacre. Unexpected result is a negative correlation of the degree of ordering of aragonitic platelets with both elastic modulus as well as microhardness. Thus the degree of ordering explains about 80% of the variability of these micromechanical properties. Statistically significant but weaker correlation was also found between micromechanical properties and textural type of bivalvian nacre. The nacre with uniaxial texture is harder and more elastic than the nacre with quasimonocrystallic texture. The data suggests that higher hardness and elasticity corresponds to a primitive state of nacre and that during the subsequent evolution values of these micromechanical properties were decreasing. This trend contradicts with generally accepted hypothesis of increassing predation pressure in the marine ecosystem during the Paleozoic and Mesozoic.
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Risks arising from breeding and introduction of aquarium snails
Jarošová, Martina ; Vrabec, Vladimír (advisor) ; Jan, Jan (referee)
Information was gathered regarding all aquarium and already introduced alien snail species (Gastropods), which are being imported to Europe. For the integrity of the research non-native and aquarium clams (Bivalve) were also included. Profiles of species were created based on collected information and the data were subsequently used for creating questionnaires. Questionnaires of each species were processed by FI - ISK, version 1.19 screening tool. Score of invasiveness risk potential was evaluated for each species individually. Surveyed taxa were divided into three groups according to their scores: low risk, medium risk and high risk. Celetaia persculpta was evaluated as aquarium snail (Gastropods) with the lowest risk for native fauna of Czech Republic. According to the results, Pomacea maculata and Pomacea canaliculata are the aquarium snails (Gastropods) with the highest invasiveness risk potential. The riskiest introduced species is Potamopyrgus antipodarum. Scabies crispata and Hyriopsis bialata are clams (Bivalve) with the least risk for the native fauna of Czech Republic. Corbicula fluminea and Dreissena polymorpha were analyzed as clams (Bivalve) with the highest invasiveness risk potential. By comparing aquarium species with species that were already introduced into Czech nature, I conclude that the aquarium snails (clams) do not represent similar risk like the alien species that were introduced without the share of aquarists.
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The complex characterisation of nematode Phasmarhabditis hermaphrodita
NERMUŤ, Jiří
Ph.D. thesis "The complex chacterisation of the nematode Phasmarhabditis hermpahrodita" is focused on the study of ecology of slug parasitic nematode P. hermaphrodita, its general characterisation in the context of all nowadays knowledge. The thesis consists the general introduction, that introduces the whole nowadays research of P. hermaphrodita, and four original works, that follow the introductory chapter. The first work deals with the orientation of P. hermaphrodita in 2D and 3D space and reaction on the presence of different hosts or nutritive substrates. The other study deals with the reaction of P. hermaphrodita on various animal and plant nutritive substrates and in the first place the influence of these substrates on the development of nematodes and quality and quantity of progeny. The third scope of this thesis is the influence of intraspecific competition on development, quality and quantity of nematodes and the last part of this text comprises a short study of the persistence of P. hermaphrodita in different substrates, from mineral to organic.
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Červená kniha biotopů České republiky
Ústav ekologie krajiny AV ČR, České Budějovice ; Kučera, Tomáš
Cílem projektu je vypracování podkladů pro knižní publikaci (rukopis), která uzavře řadu "červených knih" a vyhodnotí podle moderního pojetí ochrany přírody přírodní biotopy. Řešení projektu bylo rozděleno do tří částí: 1. Sestavení dílčích přehledů červených druhů různých skupin charakteristických pro biotopy (klasifikace podle Katalogu biotopů), 2. Sestavení vegetačních charakteristik biotopů a charakteristických druhů cévnatých rostlin, 3. Analýza prostorových charakteristik biotopů (na základě výsledků mapování biotopů).
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Krajinně-ekologické‚ vodohospodářské‚ ekonomické a legislativní hodnocení záměru výstavby kanálu Dunaj - Odra - Labe
ŠINDLAR s.r.o, Býšť ; Servus, Michal ; Zeman, Jan ; Šťovíčková, Leona ; Novotná, Pavla ; Zapletal, Jan ; Šindlar, Miloslav
Přílohy obsahující tabulky s přehledy těchto lokalit ovlivněných průplavem DOL: MZCHÚ, evropsky významné lokality, ptačí oblasti, VZCHÚ, přírodní parky, lokality s výskytem chráněných a ohrožených druhů lumbricidae, lokality s výskytem chráněných a ohrožených druhů crustacea, carabidae, odonata, lokality s výskytem významných zástupců druhů edafonu, s výskytem chráněných a ohrožených druhů amphibia, reptilia, aves, mammalia, lokalit s výskytem chráněných a ohrožených druhů rostlin. Hydrologické ovlivnění úseku toků se zástupci mollusca a se zástupci pisces.
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