Laboratory of Phytoplankton Ecology and Reservoir Limnology
Author's CV

doc. RNDr. Petr Znachor, Ph.D.

Date and place of birth: 29. 10. 1973, České Budějovice
Phone No.: +420 604 314 751, +420 38 777 5850
Email: znachy at

MSc, 1998, University of South Bohemia, České Budějovice, emphasis in phytoplankton ecology
PhD, 2003, University of South Bohemia, České Budějovice, emphasis in limnology and microbial ecology
Habilitation in Hydrobiology, 2015, University of South Bohemia, České Budějovice

1338 citations (1227 without self-citations), 56 IF publications, H-index = 22, Researcher ID: AAH-5088-2020

Areas of competence:
(i) Reservoir limnology and phytoplankton ecology, (ii) Long-term data analysis, effects of weather extremes on reservoir functioning; (iii) Fluorescence techniques, (iv) Diatom ecophysiology and microbial interactions, (v) Phytoplankton temporal dynamics and spatial distribution

Professional experience:
1998 – present: Research associate at the Institute of Hydrobiology, Biology Centre CAS
2013 – 2017: Head of the Scientific Council (IHB BC AS CR)
2018 – present: Head of the Department of Aquatic Microbial Ecology, (IHB BC AS CR)
2018 – present: Chairman of Czech Limnological Society,
2009 – present: Member of Czech Long-term Ecological Research network (LTER),

Recent projects:

2022 – 2024: leading the research project (GA ČR 22-33245S) “Effects of extreme weather events on seasonal dynamics of planktonic assemblages and reservoir water quality” (more)
2018 – 2022: co-PI of the ERDF/ESF project No CZ.02.1.01/0.0/0.0/16_025/0007417 “Biomanipulation as a tool for improving water quality of dam reservoirs”
2015 – 2017: leading the research project (P504/15-13750S): “Phytoplankton responses to environmental forcing – lessons learned from 30-year monitoring of the Římov Reservoir”
2011 – 2014: leading the research project (GA ČR No P504/11/2177): “The importance of cell death for freshwater phytoplankton succession, structure and composition”
2011 – 2014: co-investigator of the research project (GA ČR No P504/11/2182): “Phytoplankton release of dissolved organic carbon and its relationship to bacterioplankton composition”
2007 – 2009: leading the research project (GA ČR P504/15-13750S): “Mixotrophic nutrition of summer phytoplankton species in the Římov Reservoir“

Personal interests:
aerial photography, microphotography, travelling, history, medieval castles, volleyball

Scientific papers:

Viera H.H., Bulzu P., Kasalický V., Haber M., Znachor P., Piwosz K., Ghai R. (2024) Isolation of a widespread giant virus implicated in cryptophyte bloom collapse. The ISME Journal, wrae029,

Znachor P., Nedoma J., Kolar V., Matoušů A. (2023): Spatial and temporal variability of methane emissions and environmental conditions in a hyper-eutrophic fishpond. Biogeosciences 20: 4273–4288.

Park H., Šimek K., Mukherjee I., Shabarova T, Salcher M.M., Porcal P., Kosová L., Rychtecký P., Seďa J., Znachor P., Kasalický V. (2023): In the right place, at the right time: spatiotemporal distribution of bacteria in freshwater reservoir ecosystems. Microbiome 11: 112.

Čtvrtlíková M., Kopáček J., Nedoma J., Znachor P., Hekera P., Vrba J. (2023): Aquatic quillworts, Isoëtes echinospora and I. lacustris under acidic stress - a review from a temperate refuge. Ecology and Evolution. 13:e9878.

Kavagutti V., Bulzu P., Chiriac M., Salcher M., Mukherjee I., Shabarova T., Grujčić V., Mehrshad M., Kasalický V., Andrei A.S., Jezberová J., Seďa J., Rychtecký P., Znachor P., Šimek K., Ghai R. (2023): High‑resolution metagenomic reconstruction of the freshwater spring bloom. Microbiome 11: 15. DOI: 10.1186/s40168-022-01451-4

Konopáčová E., Nedoma J., Čapková K., Čapek P., Znachor P., Pouzar M., Říha M., Řeháková K. (2021): Low specific phosphorus uptake affinity of epilithon in three oligo- to mesotrophic post-mining lakes. Frontiers in Microbiology 12: 735498. DOI: 10.3389/fmicb.2021.735498

Kopáček J., Hejzlar J., Porcal P., Znachor P. (2021): Biogeochemical causes of sixty-year trends and seasonal variations of river water properties in a large European basin. Biogeochemistry 154: 81–98. DOI: 10.1007/s10533-021-00800-z

Blabolil P., Harper L.R., Říčanová Š., Sellers G., Di Muri C., Jůza T., Vašek M., Sajdlová Z., Rychtecký P., Znachor P., Hejzlar J., Peterka J., Hänfling B. (2021): Environmental DNA metabarcoding uncovers environmental correlates of fish communities in spatially heterogeneous freshwater habitats. Ecological Indicators 126: 107698. DOI: 10.1016/j.ecolind.2021.107698

Shabarova T., Salcher M.M., Porcal P., Znachor P., Nedoma J., Grossart H.P., Seďa J., Hejzlar J., Šimek K. (2021): Recovery of freshwater microbial communities after extreme rain events is mediated by cyclic succession. Nature Microbiology.

Vašek M., Souza A.T., Říha M., Kubečka J., Znachor P., Hejzlar J. (2021): Stable isotope evidence from archived fish scales indicates carbon cycle changes over the four-decade history of the Římov Reservoir (Czechia). Science of The Total Environment 755, 142550. DOI:10.1016/j.scitotenv.2020.142550

Piwosz K., Vrdoljak A., Frenken T., González-Olalla J.M., Šantić D., McKay R.M., Spilling K., Guttman L., Znachor P., Mujakić I., Kolesár Fecskeová L., Zoccarato L., Hanusová M., Pessina A., Reich T., Grossart H.P., Koblížek M. (2020): Light and Primary Production Shape Bacterial Activity and Community Composition of Aerobic Anoxygenic Phototrophic Bacteria in a Microcosm Experiment. mSphere 5: e00354-20. DOI: 10.1128/mSphere.00354-20

Cantonati M., Poikane S., Pringle C.M., Stevens L.E., Turak E., Heino J., Richardson J.S., Bolpagni R., Borrini A., Cid N., Čtvrtlíková M., Galassi D.M.P., Hájek M., Hawes I., Levkov Z., Naselli-Flores L., Saber A.A., Di Cicco M., Fiasca B., Hamilton P.B., Kubečka J., Segadelli S., Znachor P. (2020): Multiplicity, characteristics, main impacts, and stewardship of natural and artificial freshwater environments. Water 12, 260: 1-85, DOI:10.3390/w12010260

Čtvrtlíková M., Kopáček J., Nedoma J., Znachor P., Vrba J. (2020): Only the adults survive – a long-term resistance of Isoëtes lacustris to acidity and aluminium toxicity stress in a Bohemian Forest lake. Ecological Indicators 111: (2020) 106026

Znachor P., Nedoma J., Hejzlar J., Seďa J., Komárková J., Kolář V., Mrkvička T. & Boukal D. (2020): Changing environmental conditions underpin long-term patterns of phytoplankton in a freshwater reservoir. Science of the Total Environment 710: 135626. DOI:10.1016/j.scitotenv.2019.135626

Perivolioti T.M., Tušer M., Frouzová J., Znachor P., Rychtecký P., Mouratidis A., Terzopoulos D. & Bobori D. (2019): Estimating environmental preferences of freshwater pelagic fish using hydroacoustics and satellite remote sensing. Water 11: 2226. DOI: 10.3390/w11112226

Fecskeová L.K., Piwosz K., Hanusová M., Nedoma J., Znachor P., Koblížek M. (2019): Diel changes and diversity of pufM expression in freshwater communities of anoxygenic phototrophic bacteria. Scientific Reports 9: 18766. DOI: 10.1038/s41598-019-55210-x

Gabaldón C., Devetter M., Hejzlar J., Šimek K., Znachor P., Nedoma J. & Seďa J. (2019): Seasonal strengths of the abiotic and biotic drivers of a zooplankton community. Freshwater Biology 64: 1326–1341.

Andrei A.S., Salcher M. M., Mehrshad M., Rychtecký P., Znachor P. & Ghai R. (2019). Niche-directed evolution modulates genome architecture in freshwater Planctomycetes. The ISME Journal 13: 1056–1071.

Znachor P., Nedoma J., Hejzlar J., Seďa J., Kopáček J., Boukal D. & Mrkvička T. (2018): Multiple long-term trends and trend reversals dominate environmental conditions in a man-made freshwater reservoir. Science of the Total Environment 624: 24–33. doi: 10.1016/j.scitotenv.2017.12.061

Jezberová J., Jezbera J., Znachor P., Nedoma J., Kasalický V. & Šimek K. (2017): The Limnohabitans Genus Harbors Generalistic and Opportunistic Subtypes: Evidence from Spatiotemporal Succession in a Canyon-Shaped Reservoir. Applied and Environmental Microbiology 83: e01530-17. doi:10.1128/AEM.01530-17

Shabarova T., Kasalický V., Šimek K., Nedoma J., Znachor P., Posch T., Pernthaler J. & Salcher M.M. (2017): Distribution and ecological preferences of the freshwater lineage LimA (genus Limnohabitans) revealed by a new double hybridization approach. Environmental Microbiology 19: 1296–1309: doi:10.1111/1462-2920.13663

Gabaldón C., Devetter M., Hejzlar J., Šimek K., Znachor P., Nedoma J. & Seďa J. (2017): Repeated flood disturbance enhances rotifer in a zooplankton community of a small dammed mountain pond. Journal of Limnology 76: 392–304. doi: 10.4081/jlimnol.2016.1544

Znachor P., Hejzlar J., Vrba J., Nedoma J., Seďa J., Šimek K., Komárková J, Kopáček J., Šorf M., Kubečka J., Matěna J., Říha M., Peterka J., Čech M. & Vašek M. (2016): Brief history of long-term ecological research into aquatic ecosystems and their catchments in the Czech Republic. Part I: Manmade reservoirs. Institute of Hydrobiology, BC CAS, České Budějovice. 80 pp. ISBN: 978-80-86668-38-3

Vrba J., Kopáček J., Čtvrtlíková M. & Znachor P. (2016): Brief history of long-term ecological research into aquatic ecosystems and their catchments in the Czech Republic. Part II: Glacial lakes. Institute of Hydrobiology, BC CAS, České Budějovice. 32 pp. ISBN: 978-80-86668-35-2

Vašek M., Prchalová M., Říha M., Blabolil P., Čech M., Draštík V., Frouzová J., Jůza T., Kratochvíl M., Muška M., Peterka J., Sajdlová Z., Šmejkal M., Tušer M., Vejřík L., Znachor P., Mrkvička T., Seďa J. & Kubečka J. (2016): Fish community response to the longitudinal environmental gradient in Czech deep-valley reservoirs: implications for ecological monitoring and management. Ecological Indicators 63: 219–230. doi10.1016/j.ecolind.2015.11.061

Znachor P., Rychtecký P., Nedoma J. & Visocká V. (2015): Factors affecting growth and viability of natural diatom populations in the meso-eutrophic Římov Reservoir (Czech Republic). Hydrobiologia 762: 253–265. doi 10.1007/s10750-015-2417-8

Rychtecký P., Znachor P., Nedoma J. (2014): Spatio-temporal study of phytoplankton cell viability in a eutrophic reservoir using SYTOX Green nucleic acid stain. Hydrobiologia 740:177–189. doi:10.1007/s10750-014-1952-z.

Čtvrtlíková M., Znachor P. & Vrba J (2014): The effect of temperature on the phenology of germination of Isoëtes lacustris. Preslia 86: 279–292.

Šimek K., Nedoma J., Znachor P., Kasalický V., Jezbera J., Horňák K., Seďa J. (2014): A finely tuned symphony of factors modulates the microbial food web of a freshwater reservoir in spring. Limnology and Oceanography 59: 1477–1492. doi:10.4319/lo.2014.59.5.1477.

Šorf M., Brandl Z., Znachor P. & Vašek M (2014): Different effects of planktonic invertebrate predators and fish on the plankton community in experimental mesocosms. Annales de Limnologie – International Journal of Limnology 50: 71–83.

Borovec J., Hejzlar J., Znachor P., Čtvrtlíková M., Blabolil P., Říha M., Matěna J., Kubečka J. (2013): Metodika pro hodnocení ekologického potenciálu silně ovlivněných a umělých vodních útvarů – kategorie jezero – návrh. Methodology for assessing Ecological potential of heavily modified and artificial water bodies) In: Kosour D., (ed). Vodní nádrže 2013, 25-26.9. 2013, Brno, Povodí Moravy s.p.: 33-38.

Šorf M., Brandl Z., Znachor P. & Vašek M (2013): Floating large-volume mesocosms as a simple, low-cost experimental design suitable for the variety of lakes and reservoirs. Fundamental and Applied Limnology 183: 41–48.

Znachor P., Visocká V., Nedoma J. & Rychtecký P. (2013): Spatial heterogeneity of diatom silicification and growth in a eutrophic reservoir. Freshwater Biology 58: 1889–1902.

Eiler A., Drakare S., Bertilsson S., Pernthaler J., Peura S., Rofner C., Šimek K., Yang Y., Znachor P. & Lindstom ES. (2013): Unveiling distribution patterns of freshwater phytoplankton by a next generation sequencing based approach. PLOS ONE 8: 1–10.

Čech M., Peterka J., Říha M., Jůza T., Kratochvíl M., Draštík V., Muška M., Znachor P. & Kubečka J. (2012): Extremely shallow spawning of Perch (Perca fluviatilis L.): The roles of sheltered bays, dense semi-terrestrial vegetation and low visibility in deeper water. Knowledge and Management of Aquatic Ecosystems 406: 1–12.

Kratochvíl M., Mrkvička T., Vašek M., Peterka J., Čech M., Draštík V., Jůza T., Matěna J., Muška M., Sed'a J., Znachor P. & Kubečka, J. (2012): Littoral age 0+ fish distribution in relation to multi-scale spatial heterogeneity of a deep-valley reservoir. Hydrobiologia 696: 185–198.

Znachor P., Šimek K. & Nedoma J. (2012): Bacterial colonization of the freshwater diatom Fragilaria crotonensis. Aquatic Microbial Ecology 66: 87–94.

Čtvrtlíková M., Znachor P., Nedoma J. & Vrba J. (2012): Effects of temperature on the phenology of germination of Isoetes echinospora. Preslia 84: 141–153.

Rychtecký P. & Znachor P. (2011): Spatial heterogeneity and seasonal succession of phytoplankton along the longitudinal gradient in a eutrophic reservoir. Hydrobiologia 663: 175–186.

Znachor P., Nedoma J. & Rychtecký P. (2011): Kinetics of glucose stimulatory effect on silica deposition and growth of natural populations of Fragilaria crotonensis. Phycological Research 59: 123–128.

Znachor P. & Nedoma J. (2010): Importance of dissolved organic carbon for phytoplankton nutrition in a eutrophic reservoir. Journal of Plankton Research 32: 367–376.

Iluz D., Dishon G., Capuzzo E., Meeder E., Astoreca R., Montecino V., Znachor P., Edider D. & Marra J. (2009): Short-term variability in primary productivity during a wind-driven diatom bloom in the Gulf of Eilat (Aqaba). Aquatic Microbial Ecology 56: 205-215.

Cao X, Song Ch, Zhou Y. Štrojsová A., Znachor P., Zapomělová E. & Vrba J. (2009): Extracellular phosphatases produced by phytoplankton and other sources in shallow eutrophic lakes (Wuhan, China): taxon-specific versus other sources. Limnology 10: 99–104.

Čtvrtlíková M., Vrba J., Znachor P. & Hekera P. (2009): Effects of aluminium toxicity and low pH on the early development of Isoetes echinospora. Preslia 81: 135–149.

Zapomělová E., Hisem D., Řehaková K., Hrouzek P., Jezberová J., Komárková J., Korelusová J. & Znachor P. (2008): Experimental comparison of phenotypical plasticity and growth demands of two strains from the Anabaena circinalis/A. crassa complex (cyanobacteria). Journal of Plankton Research 30: 1257–1269.

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: 249–262.

Znachor P., Zapomělová E., Řeháková K., Nedoma J. & Šimek K. (2008): The effect of extreme rainfall on summer succession and vertical distribution of phytoplankton in a lacustrine part of a eutrophic reservoir. Aquatic Sciences 70: 77–86.

Znachor P. & Nedoma J. (2008): Application of the PDMPO technique in studying silica deposition in natural populations of Fragilaria crotonensis (Bacillariophyceae) at different depths in a eutrophic reservoir. Journal of Phycology 44: 518–525.

Zapomělová E., Řeháková K., Znachor P. & Komárková J. (2007): Morphological diversity of coiled planktonic types of the genus Anabaena (cyanobacteria) in natural populations – taxonomic consequences. Cryptogamie/Algologie 28: 353–371.

Znachor P., Jurczak T., Komárková J., Jezberová J., Mankiewicz J., Kaštovská K. & Zapomělová E. (2006): Summer changes of cyanobacterial bloom composition and microcystin concentration in eutrophic Czech reservoirs. Environmental Toxicology 21: 236–243.

Znachor P., Vrba J., Nedoma J. & Kopáček J. (2005): Bacterial and phytoplankton responses to nutrient and pH changes during short term in situ experiments in two acidified lakes. Algological Studies 115: 79–99.

Znachor P. & Lodeová J. (2005): The occurrence of a bloom-forming green alga Pleodorina indica (Iyengar) Nozaki (Volvocales) in the downstream reach of the River Malše (Czech Republic). Hydrobiologia 541: 221–228.

Cao X., Štrojsová A., Znachor P., Zapomělová E., LIU G., Vrba J. & Zhou Y. (2005): Detection of extracellular phosphatases in natural spring phytoplankton of a shallow eutrophic lake (Donghu, China). European Journal of Phycology 40: 251–258.

Boutte C., Komárková J., Grubisić S., Znachor P., Bataille A., Zapomělová E., Gullukaya A., Jezberová J. & Wilmotte A. (2005): A polyphasic approach to assess the cyanobacterial diversity of summer samples from Czech water bodies. Hoffmann,L., Komárek, J.: Cyanobacteria/Cyanophyta - 16. Symposium Internat. Assoc. for Cyanophyte Research (IAC), Luxemburg, 2004 / Proceedings, Morphology, Taxonomy, Ecology (Papers on Cyanobacterial Research, No. 6).

Znachor P. & Nedoma, J. (2004): Cell specific primary production of autotrophic and mixotrophic phytoplankton in acidified lakes of the Bohemian Forest. Algological Studies 112: 141–155.

Štrojsová A., Vrba J., Nedoma J., Komárková J. & Znachor P. (2003): Seasonal study on expression of extracellular phosphatases in the phytoplankton of a eutrophic reservoir. European Journal of Phycology 38: 295–306.

Nedoma J., Straškrabová V., Znachor P. & Vrba, J. (2003): Primary and bacterial production in three acidified lakes in the Bohemian Forest. Silva Gabreta 9: 53–70.

Znachor P. (2003): Cell-specific primary production of autotrophic and mixotrophic phytoplankton in acidified lakes of the Bohemian forest. PhD thesis, BF JU, České Budějovice, 55 pp.

Znachor P. & Hrubý P. (2000): Cell specific primary production and phagotrophy of phytoplankton in acidified lakes of Bohemian Forest. Silva Gabreta 4: 223–232.

Znachor P. (1997): Phytoplankton diversity, intracellular phosphorus content and spatial heterogeneity along the longitudinal profile of the Lipno Reservoir, in Czech. Master thesis BF JU, České Budějovice, 51 pp.

Znachor P. (1995): Seasonal dynamics of the phytoplankton in the Lipno Reservoir in 1993, in Czech. Bachelor thesis BF JU, České Budějovice, 32 pp.