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Vertical gradient of ambient air pollutant levels
Binda, Denis ; Hůnová, Iva (advisor) ; Zíková, Naděžda (referee)
Ambient air pollution, caused by harmful pollutants, is considered a severe problem for the natural environment and its components. Effective pollution regulation is possible with reliable data from monitoring stations covering the whole country. Those stations are mainly located at the altitude of 2 m above the surface, possessing their well-known horizontal representativeness. However, the knowledge of the vertical representativeness of these monitoring stations is not sufficient, causing problems while determining the relevance of these measurements for studying the effects of pollutants in various altitudes. The gradient of ozone concentration (determining the change of ozone concentration for each 10 m) was computed to determine the vertical profile of tropospheric ozone (the gradient in this work is using the unit [μg.m-3 /10 m]). Data, containing the ozone concentrations, were measured in altitudes of 2, 8, 50 and 230 m and sourced from the National atmospheric observatory Košetice in the time interval from 6.9.2013 to 31.12.2020. The ozone concentrations show a yearly periodicity, with higher values during the summer period (from 1.4. to 30.9.) and lower values during the winter period (from 1.10. to 31.3.). The gradient for layer 230-50 m outlines considerable stability throughout the year...
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The importance of various habitats for fish in reservoirs
Šmejkal, Marek ; Prchalová, Marie (advisor) ; Vašek, Mojmír (referee)
Fish distribution in reservoirs is not homogeneous. Fish usually occur in upper parts of reservoirs on the longitudinal axis, where is also the greatest concentration of nutrients. Fish abundance and biomass as well as the trophy are declining towards the dam part. On the vertical axis, most fish occur above the thermocline, where temperature and concentration of dissolved oxygen reach the highest values. Fish community is changing also in time. Shortly after impoundment, the riverine species are dominating the community and later, generalist species prevail. Generally, we can distinguish pelagic and bentic habitats within the reservoir. There are species in reservoirs that occur almost strictly in pelagic habitat like asp and bleak and benthic species like ruffe and perch. Most species occur in both types of habitats (bream, roach, pikeperch, European catfish, white bream). Migrations between habitats occur on daily and on seasonal basis. On daily basis, we distinguish diel horizontal migration, in which fish shift between pelagic and benthic habitats. Diel vertical migration, when fish change depths, is not so significant in Czech reservoirs. Motivations for these diel migrations are food aviability, predation pressure and water temperature. Seasonal migrations comprise spawning migrations and winter...
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The importance of various habitats for fish in reservoirs
Šmejkal, Marek ; Vašek, Mojmír (referee) ; Prchalová, Marie (advisor)
Fish distribution in reservoirs is not homogeneous. Fish usually occur in upper parts of reservoirs on the longitudinal axis, where is also the greatest concentration of nutrients. Fish abundance and biomass as well as the trophy are declining towards the dam part. On the vertical axis, most fish occur above the thermocline, where temperature and concentration of dissolved oxygen reach the highest values. Fish community is changing also in time. Shortly after impoundment, the riverine species are dominating the community and later, generalist species prevail. Generally, we can distinguish pelagic and bentic habitats within the reservoir. There are species in reservoirs that occur almost strictly in pelagic habitat like asp and bleak and benthic species like ruffe and perch. Most species occur in both types of habitats (bream, roach, pikeperch, European catfish, white bream). Migrations between habitats occur on daily and on seasonal basis. On daily basis, we distinguish diel horizontal migration, in which fish shift between pelagic and benthic habitats. Diel vertical migration, when fish change depths, is not so significant in Czech reservoirs. Motivations for these diel migrations are food aviability, predation pressure and water temperature. Seasonal migrations comprise spawning migrations and winter...
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Changes in centipede assemblages (Chilopoda) along the vertical and vegetation gradient in the Bieszczady Mountains, Poland
Wytwer, J. ; Tajovský, Karel
Changes in community parameters of the centipede assemblages in habitats with different vegetation along the vertical gradient were studied in the Bieszczady National Park, Poland. Ten stands, from riparian alder forest through eutrophic beech forests to open habitats in subalpine grasslands, within the altitude range 612–1,218 m a.s.l. were sampled. Pitfall trapping and soil sampling were used for the collection of animals since June 2005 till June 2006. In total, 848 specimens of centipedes belonging to 19 species were sampled. Among them, the species .i.Lithobius latro./i. was recorded in Poland for the first time. .i.Lithobius lucifugus, Strigamia transsilvanica, Geophilus insculptus, Schendyla carniolensis./i. were found in this region of Poland for the first time. Specimens of the genus .i.Stenotaenia./i. recorded in the study sites represent a new stenotopic species. Between 7 and 14 species were found in each stand.
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