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Investigations of diseases with natural focality in Biospheric Protection Area Pálava
Hubálek, Zdeněk ; Halouzka, Jiří ; Juřicová, Zina
Long-term studies of the Medical Zoology Laboratory at the Institute of Vertebrate Biology of the Academy of Sciences of the Czech Republic concentrate on natural foci of diseases transmitted by haematophagous arthropods in this area, e.g., Valtice fever (the etiologic agent is mosquito-borne ahyňa virus), Lyme borreliosis (the agent is tick-borne Borrelia burgdorferi sensu lato) or tularemia (the agent is Francisella tularensis that is occasionally transmitted also by ixodid ticks). We detected newly the activity of mosquito-borne West Nile virus in this area, and additional tick-borne pathogens might be expected (Anaplasma phagocytophilum, Babesia microti). In addition, our laboratory has investigated the ecology of some non-tramissible diseases, e.g. avian botulism, salmonellosis in gulls and emmonsiosis in rodents; the latter two diseases also occur in humans.
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Bottom soils in the rhizospheres of quillworts in the Czech Republic Bohemian Forest
Husák, Štěpán
The bottom soil from the rhizosphere of both quillwort species (Isoëtes lacustris and I. echinospera) was sampled in the Plešné and Černé lakes in the Bohemian Forest by C. Weilner and his collaborators (1996, 1998) and by M. Böhm (2002), and analysed in the chemical laboratory of the Institute of Botany, Czech Academy of Sciences, Průhonice (see Tab. 1.). The results of chemical analyses from the three years are comparable with smoothly increasing values. Only the potassium concentrations decreased from 116.25 mg.kg-1in 1996 to 5.75 mg.kg-1 in 2002 in Plešné Lake. This decrease can be explained by greater flushing of the sediments from the cirque walls into the stands of Isoëtes echinospora, in 1996. From 2004 to 2006 the bottom soils from Isoëtes stands will be analysed twice per year, with more samples from the Isoëtes stands. Nutrients will also be assessed on the radient between the Isoëtes stands and the shores of both lakes.
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Algae of Černé Lake in the Bohemian Forest
Lukavský, Jaromír
Algae and Cyanobacteria of Bohemian Forest are presented, as an important part of plant communities. Streams, bogs, arophytic ans subaerophytic standorts, phytoplankton of lakes and cryoseston are discussed and presented in tables and microphotographs.Bohemian Forest is an important refugium of oligotrophic species and a classic locality for therir study.
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Past and present of the "Angling Paradise" (fishing-ground of the Moravian Anglers Union, Dyje 7)
Baruš, Vlastimil ; Prokeš, Miroslav ; Peňáz, Milan
The comparison of fishery catches in the fishing-ground MRS Dyje 7 during the riverine (1953-1978) and lake (1981-2003) periods shows differences in species composition and quantity. Due to impoundment and fishery management (stocking), carp, bream, perch, pikeperch, asp and wels increased their production considerably. The area studied belongs presently to the most productive MRS fishing-grounds with a mean annual yield of almost 50 tones fish (95,8 kg.ha-1).
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Growth of the sterlet (Acipenser ruthenus) under conditions of Pohořelice Pond Fisheries
Baránek, V. ; Prokeš, Miroslav ; Baruš, Vlastimil ; Peňáz, Milan ; Mareš, J. ; Spurný, P. ; Němec, R.
Growth results of the sterlet (Acipenser ruthenus) reared at the Pohořelice Pond Fisheries were observed in 2003 and 2004 and subsequently analysed. During the period 28 July ů 2 September 2003 a feeding experiment (sterlet of age 1+ and 4+, 5+) was performed in which very good growth parameters were achieved: In the age category 1+ (initial mean weight of 99,5; 71,2 and 53,8 g) using DFR 1,6; 1,7; 2,1 % respectively, SWGR 1,02; 1,36; 0,91 %.d-1 , respectively and FCR 1,45; 1,10 and 2,38, respectively. In the age category 4+, 5+ (initial mean weight of 316,9; 375,0 and 478,85 g) using DFR 1,3; 1,1 and 0,9 %, respectively, SWGR 0,88; 0,73 and 0,59 %.d-1 , respectively and FCR 1,35; 1,39 and 1,42, respectively. On the basis of these results, sterlet may be considered to be an appropriate fish for intensive aquaculture and, as a native species for the Czech Republic, also for stocking into Czech running waters.
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Foraging strategy of ungulates on Pavlovske vrchy hills
Heroldová, Marta
Study on foraging strategy of three ungulate species (Capreolus capreolus, Capra aegagrus, Ovis musimon) elucidates the problem of mutual coexistence and competition. High impact on unique flora of Palava Hills leaded to decision to lower the number of ungulates and eliminate Capra aegagrus from this locality.
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The natural fish reproduction of lowland stretches of Morava and Dyje rivers
Valová, Z. ; Jurajda, Pavel
Lowland rivers decreased their habitat diversity and get an uniform character due to their regulation and channelisation. This modifications affected the natural fish reproduction. The efficiency of natural fish reproduction was studied using Point Abundance Sampling strategy by electrofishing in three differently modified stretches of two adjacent lowland rivers in the late summer of 1999-2003.
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