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Photosynthetic characteristics of phytoplankton in eutrophic waters
Tesařová, Blanka ; Pechar, Libor (advisor) ; Fott, Jan (referee)
Photosynthesis and primary production were estimated in fishpond phytoplankton during period 2008-2010 in Třeboň fishpond region, Czech Republic. Photosynthesis was measured by the oxygen method in computer-assisted light pipetting system Illuminova. Altogether 64 samples of fishpond phytoplankton and 11 cyanobacterial cultures were analysed. Cyanobacteria and chlorococcal algae formed the most important part of phytoplankton biomass and their photosynthesis-irradiance (P-I) curves showed shade-adapted type of P-I curves with the high photosynthetic efficiency. No significant differences in the main parameters of P-I curves were obtained between different types of phytoplankton (chlorococcal-dominated, cyanobacteria- dominated). The results are consistent with the high turbid conditions in eutrophic or hypetrophic fishponds. On the contrary photosynthesis in cyanobacterial cultures differs from "wild" phytoplankton and therefore they can not be taken in primary production models. Primary production was estimated according Talling's model (1957), based on daily measurement of radiation, extinction coefficient of water and seasonal courses of chlorophyll concentration. Photosynthetic capacity and onset of light saturation determined in P-I curves were used as physiological parameters of Talling's model. The...
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Water quality change in small watersheds after sewage water treatment plant building
Rödlová, Sylva ; Langhammer, Jakub (advisor) ; Kvítek, Tomáš (referee) ; Pechar, Libor (referee)
Změny kvality vody v malých tocích, vyvolané vybudováním čistírny odpadních vod, představují doposud málo studované a přitom velmi aktuální téma současné hydrologie. Tato studie se zabývá popsáním těchto změn a faktorů, které je ovlivňují. Pro účely výzkumu bylo vybráno pět malých, zemědělsky využívaných povodí prvního řádu (čtyři povodí průměrně 6 km2 , jedno 16 km2 ). V každém zájmovém území byla vždy jedna vesnice od 640 do 2 500 obyvatel. Během 7 - 16 let trvajícího měsíčního monitoringu základních indikátorů kvality vody (O2, BSK5, CHSKCr, TOC, konduktivita, N-NH4, N-NO2, N-NO3, PC, P-PO4) byla zachycena stavba čistíren v obcích. Spolu s daty o účinnosti čistíren byly vyhodnoceny změny kvality vody v toku. Identifikované typy změn ukazují na problematické aspekty vývoje kvality vody v malých povodích. Kromě očekávaného rychlého a razantního snížení hodnot zátěže po výstavbě čistírny odpadních vod se vyskytují i odlišné projevy změn - pouze mírné snížení zátěže, stagnace, dokonce i zvýšení koncentrací sledovaných indikátorů. Mezi další typické změny patří navýšení hodnot 1-2 roky před uvedením čistírny do provozu a opožděná nitrifikace v toku způsobená nevhodným provozem čistírny. Mezi nejdůležitější faktory ovlivňující změny patří provoz čistírny, velikost průtoku recipientu, zemědělské...
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Surface water temperature modelling to estimate Czech fishery productivity under climate change
Svobodová, Eva ; Trnka, Miroslav ; Kopp, R. ; Mareš, J. ; Spurný, P. ; Pechar, L. ; Beděrková, I. ; Dubrovský, M. ; Žalud, Zdeněk
Freshwater fish production is significantly correlated with water temperature, which is expected to increase under climate change and affect fish growth, productivity, and survival. This study deals with estimating the change in water temperature in productive ponds and its impact on fishery in the Czech Republic. The target fish species were common carp (Cyprinus carpio), maraena whitefish (Coregonus maraena), northern whitefish (Coregonus peled), and rainbow trout (Oncorhynchus mykiss). It was hypothesized that there would be an increasing risk of high water temperature stress for fish. Water temperature calculations based on 3-day means of air temperature were tested in several ponds in three major fish production areas. The verified model was applied to the climate change conditions determined by standardized scenarios derived from the five global circulation models MPEH5, CSMK3, IPCM4, GFCM21, and HADGEM. The results for changed climate indicated limitations for Czech fish farming in terms of prolonged periods with fish temperature stress as well as the increased number of stress periods and increased number of days within these periods. It is very likely that Czech fishery will have to change the fish species farmed in particular productive areas. In particular, higher altitudes are likely to become less suitable for the Salmonidae.
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Measurements and the use of spectral reflectance of solar radiation from surface water levels
Vinciková, H. ; Pechar, L. ; Hanuš, Jan
The methodology describes measurement of spectral reflectance from the surface of water bodies and application of the measured reflectance in assessment and monitoring of water quality especially in terms of the range of eutrophication and development of water blooms. The aim of the suggested methodology is to provide an effective tool for a rapid screening of water quality situation in the Czech Republic, including relatively large areas, and therefore from more water bodies at once. This method using remote sensing allows to gather lot of data on water quality without time-consuming and overall more expensive field sampling and laboratory analysis.
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Vegetation carbon-stores and net primary in upper Stropnice river catchment
Stará, Lenka ; Bodlák, L. ; Pokorný, J. ; Macků, J. ; Janderková, J. ; Šefrna, L. ; Středa, T. ; Burešová, Renata ; Pechar, Libor ; Cudlín, Pavel
Vegetation carbon-stores were quantified and net primary production estimated in upper Stropnice river catchment.Subsequently carbon cycle in the studied territory was composed for to estimate the total carbon balance of the area.Based on the results studied territory appear to be a carbon sink,i.e.carbon storing area.
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Zeleň a urbánní plánování
Hanousková, Irena ; Hanousek, P. ; Charvátová, J. ; Pechar, L.
The additional proceedings summarizes contributions presented during Final COST C11 Seminar held at České Budějovice 2nd - 4th of December 2004. Conclusions of working groups WG 1A Ecology, WG 1B Human issues, WG 2 Policies were presented, evaluated and finally discussed. The examples of European cities green structures were extended by (new) experience of the České Budějovice particular conditions. The nowadays greenstructure utilization, interaction with users, planning, management and future development are discussed, including important instruments and challenges.
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