Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Hydrobiology

Staff List

Horňák, Karel

hornak@hbu.cas.cz

+420 387 775 834
http://www.hbu.cas.cz/show.php?show=89&lang=en

Papers:

Grossart, H.P., Jezbera, J., Horňák, K., Hutalle, K.M.L., Buck, U., Šimek, K.
(2008) Top-down and bottom-up induced shifts in bacterial abundance, production and community composition in an experimentally divided humic lake. Environmental Microbiology, 10 (3): 635–652.
Research impacted

Horňák, K., Jezbera, J., Šimek, K.
(2008) Effects of a Microcystis aeruginosa bloom and bacterivory on bacterial abundance and activity in a eutrophic reservoir. Aquatic Microbial Ecology, 52 (2): 107–117.
Research impacted

Šimek, K., Horňák, K., Jezbera, J., Nedoma, J., Znachor, P., Hejzlar, J., Seďa, J.
(2008) Spatio-temporal patterns of bacterioplankton production and community composition related to phytoplankton composition and protistan bacterivory in a dam reservoir. Aquatic Microbial Ecology, 51 (3): 249–262.
Research impacted

Posch, T.*, Mindl, B.*, Horňák, K., Jezbera, J., Salcher, M.M.*, Sattler, B.*, Sonntag, B.*, Vrba, J., Šimek, K.
(2007) Biomass reallocations within freshwater bacterioplankton induced by manipulating phosphorus availability and grazing. Aquatic Microbial Ecology, 49 (3): 223–232.
Research impacted

Weinbauer, M.G.*, Horňák, K., Jezbera, J., Nedoma, J., Dolan, J.R.*, Šimek, K.
(2007) Synergistic and antagonistic effects of viral lysis and protistan grazing on bacterial biomass, production and diversity. Environmental Microbiology, 9 (3): 777–788.
Research impacted

Šimek, K, Weinbauer, M.G.*, Horňák, K., Jezbera, J., Nedoma, J., Dolan, J.R.*
(2007) Grazer and virus-induced mortality of bacterioplankton accelerates development of Flectobacillus populations in a freshwater community. Environmental Microbiology, 9 (3): 789–800.
Research impacted

Salcher, M.M.*, Hofer, J.*, Horňák, K., Jezbera, J., Sonntag, B.*, Vrba, J., Šimek, K., Posch, T.*
(2007) Modulation of microbial predator-prey dynamics by phosphorus availability: Growth patterns and survival strategies of bacterial phylogenetic clades. FEMS Microbiology Ecology, 60 (1): 40–50.
Research impacted

Groben, R.*, Hahn, M.W.*, Horňák, K., Mergeay, J.*, Šimek, K., Vrba, J.
(2007) Meeting report: ALTER-Net workshop about the “Application of molecular techniques to study biodiversity, structure and function of planktonic communities in lakes” at Blanes, Spain, February 15–16, 2007. Protist, 158 (4): 417–421.
Others

Horňák, K., Jezbera, J., Nedoma, J., Gasol, J.M.*, Šimek, K.
(2006) Effects of resource availability and bacterivory on leucine incorporation in different groups of freshwater bacterioplankton, assessed using microautoradiography. Aquatic Microbial Ecology, 45 (3): 277–289.
Research impacted

Horňák, K., Jezbera, J., Nedoma, J., Šimek, K.
(2006) Decreased activity of free-living reservoir bacterioplankton during summer cyanobacterial bloom. In: Book of Abstracts, 5th International Conference on Reservoir Limnology and Water Quality, Brno, August 27–31, 2006. Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Hydrobiology, České Budějovice; Centre for Cyanobacteria and Their Toxins, Masaryk University Brno. ISBN 80–86188–23–X: pp. 44–47.
Others

Jezbera, J., Horňák, K., Šimek, K.
(2006) Prey selectivity of bacterivorous protists in different size fractions of reservoir water amended with nutrients. Environmental Microbiology, 8 (8): 1330–1339.
Research impacted

Šimek, K., Jezbera, J., Horňák, K., Nedoma, J., Hejzlar, J., Straškrábová, V.
(2006) Growth rates of major bacterioplankton groups in relation to phosphorus availability in a canyon-shaped reservoir. In: Book of Abstracts, 5th International Conference on Reservoir Limnology and Water Quality, Brno, August 27–31, 2006. Biology Centre of the Academy of Sciences of the Czech Republic, Institute of Hydrobiology, České Budějovice; Centre for Cyanobacteria and Their Toxins, Masaryk University Brno. ISBN 80–86188–23–X: pp. 40–43.
Others

Šimek, K., Horňák, K., Jezbera, J., Nedoma, J., Vrba, J., Straškrábová, V., Macek, M., Dolan, J.R.*, Hahn, M.W.*
(2006) Maximum growth rates and possible life strategies of different bacterioplankton groups in relation to phosphorus availability in a freshwater reservoir. Environmental Microbiology, 8 (9): 1613–1624.
Research impacted

Horňák, K., Mašín, M., Jezbera, J., Bettarel, Y.*, Nedoma, J., Sime-Ngando, T.*, Šimek, K.
(2005) Effects of decreased resource availability, protozoan grazing and viral impact on a structure of bacterioplankton assemblage in a canyon-shaped reservoir. FEMS Microbiology Ecology, 52 (3): 315–327.
Research impacted

Jezbera, J., Horňák, K., Šimek, K.
(2005) Food selection by bacterivorous protists: insight from the analysis of the food vacuole content by means of fluorescence in situ hybridization. FEMS Microbiology Ecology, 52 (3): 351–363.
Research impacted

Šimek, K., Horňák, K., Jezbera, J., Mašín, M., Nedoma, J., Gasol, J.M.*, Schauer, M.*
(2005) Influence of top-down and bottom-up manipulations on the R-BT065 subcluster of b-proteobacteria, an abundant group in bacterioplankton of a freshwater reservoir. Applied and Environmental Microbiology, 71 (5): 2381–2390.
Research impacted

Šimek, K., Jezbera, J., Horňák, K., Vrba, J., Seďa, J.
(2004) Role of diatom-attached choanoflagellates of the genus Salpingoeca as pelagic bacterivores. Aquatic Microbial Ecology, 36: 257–269.
Research impacted

Šimek, K., Horňák, K., Mašín, M., Christaki, U.*, Nedoma, J., Weinbauer, M.G.*, Dolan, J.R.*
(2003) Comparing the effects of resource enrichment and grazing on a bacterioplankton community of a meso-eutrophic reservoir. Aquatic Microbial Ecology, 31(2): 123-135.
Research impacted

Horňák K., Mašín M., Jezbera J., Nedoma J., Šimek K.
(2003) Vliv živin a predace prvoků na složení společenstva bakterií přeneseného z živinami bohatého do živinami chudého prostředí přehradní nádrže [Effects of nutrients and protozoan grazing on community composition of bacteria that were transferred from a nutrient-rich to a nutrient-poor area of a reservoir]. Acta Facultatis Ecologiae: 10 (Suppl. 1): 23-25.
Others

Koutný, J.*, Rulík, M.*, Navrátil, M.*, Jezbera, J., Horňák, K.
(2003) Stanovení hlavních fylogenetických skupin bakterií v hyporheických sedimentech malého nížinného toku (Sitka, ČR) pomocí fluorescenční hybridizace in situ (FISH)[Determination of the main phylogenetic groups of bacteria in the hyporheic sediments of the small lowland creek (Sitka, Czech republic) using fluorescent in situ hybridization (FISH)]. Acta Facultatis Ecologiae: 10 (Suppl. 1): 35-37.
Others

Mašín, M., Horňák, K., Jezbera, J., Nedoma, J., Šimek, K.
(2003) Vliv živin a predace prvoky na změny morfologie bakterií při manipulačních pokusech v nádrži Římov [Effects of nutrients and protozoan grazing on changes of bacterial morphology during manipulation experiments in Římov reservoir]. Acta Facultatis Ecologiae: 10 (Suppl. 1): 27-30.
Others

Šimek, K., Horňák, K., Mašín, M., Nedoma, J., Weinbauer, M.*
(2003) Faktory ovlivňující složení společenstev bakterioplanktonu [Factors shaping community composition of bacterioplankton]: Acta Facultatis Ecologiae: 10 (Suppl. 1): 19-21.
Others

Bettarel, Y.*, Dolan, J.R.*, Horňák, K., Lemée, R.*, Mašín, M., Pedrotti, M.-L.*, Rochelle-Newall, E.*, Šimek, K., Sime-Ngando, T.*
(2002) Strong, weak, and missing links in microbial community of the N.W. Mediterranean Sea. FEMS Microbiology Ecology, 42: 451–462.
Research impacted

Horňák, K.*, Mašín, M.*, Nedoma, J., Šimek, K.
(2002) Využití genetických sond při studiu bakterioplanktonu vodárenské nádrže Římov (Use of genetic probes to study bacterioplankton of Římov reservoir). In: Ambrožová, J. (ed.): 18. seminář Aktuální otázky vodárenské biologie, Praha, February 6–7, 2002, VŠCHT, Praha, pp. 125–1290. ISBN 80–7080–467–X.
Others

Šimek, K., Mašín, M., Horňák, K., Nedoma, J., Hejzlar, J.
(2002) Factors controlling dynamics and community composition of microbial assemblages in a canyon-shaped reservoir In: Hydrobiological Institute AS CR (eds.): ResLim 2002, Extended Abstracts, 4th International Conference on Reservoir Limnology and Water Quality, České Budějovice, August 12–16, 2002, Institute of Hydrobiology Academy of Sciences of the Czech Republic, Faculty of Biological Sciences University of South Bohemia, pp. 314-317.
Others

Šimek, K., Pernthaler, J.*, Weinbauer, M.G.*, Horňák, K.*, Dolan, J.R.*, Nedoma, J., Mašín, M.*, Amann, R.*
(2001) Changes in bacterial community composition and dynamics and viral mortality rates associated with enhanced flagellate grazing in a mesoeutrophic reservoir. Applied and Environmental Microbiology, 6: 2723-2733.
Research impacted

Šimek, K., Horňák, K., Mašín, M., Nedoma, J.
(2000) Vliv protozoální predace na dynamiku a složení bakteriálních společenstev v nádrži Římov (Impacts of protistan bacterivory on the dynamics and community composition of bacterioplankton in the Římov reservoir). In: Rulík, M. (ed.), XII. Limnologická konference Limnologie na přelomu tisíciletí, Kouty nad Desnou, September 18-22, 2000, Univerzita Palackého Olomouc, pp. 43-46.
Others