Looduslike ja inimtekkeliste survetegurite mõju Peipsi järve suurtaimestikule

A Thesis for applying for the degree of Doctor of Philosophy in HydrobiologyMacrophytes play an important role in aquatic ecosystems. Their temporal and spatial distribution is governed by various natural and anthropogenic pressures and disturbances. The aim of the thesis is to study the effect of pressures and disturbances on species composition and richness in Lake Peipsi. The fluctuating water level has been considered to be a natural disturbance factor while eutrophication and reed removal are important anthropogenic influences. During the rapid eutrophication between 1970 and 1980, the frequency of common hygrophytes, helophytes, and amphibious plants increased, as well as the frequency of filamentous green algae. Eutrophication of Peipsi has had a profound effect on macrophytes because it has induced the expansion of reeds, which in turn decreased suitable eulittoral habitats for small-sized species. The expansion of reeds required holidaymakers and local people to manage the lake shores more actively. In general, management supports increase in species richness but the formation of dry ‘terraced’ (elevated) areas should not be the first choice. Among the different management styles the highest species richness was found in the stretches without ‘terrace’ or with a combination of managed and wild habitats. Further, changes in the water level create new ecological niches and a mosaic of habitats. At low water habitats emerge for otherwise declining species such as Alisma gramineum, Ranunculus reptans, Cyperus fuscus. Thus, the water level fluctuation as an intermediate disturbance supports species richness in Peipsi. Remarkably, also the abundance of submerged macrophytes, charophytes and large filamentous algae increased considerably at the low water level. Therefore, the occurrence of indicator species and its influence on the estimation of ecological quality are in synchrony with the natural disturbance factor.Makrofüütidel ehk suurtaimedel on väga oluline roll nii vee keemiliste omaduste mõjutajana kui ka elu- ja varjepaigana ning toidubaasina paljudele teistele liikidele. Seepärast on oluline jälgida suurtaimestikus toimuvaid muutusi ning tuvastada looduslike ja inimtekkeliste survetegurite osa nende kujunemisel. Töö põhineb Peipsi järve pikaajalistel uuringutel. Inimtekkeliste surveteguritena on käsitletud eutrofeerumist ja pilliroo eemaldamist (ühekordsena käsitletav ka häiringuna) ning loodusliku häiringuna veetaseme kõikumist. Kiire eutrofeerumise perioodil (1970–1980) suurenes oluliselt tavaliste hügrofüütide, helofüütide, amfiibsete liikide ning suurte niitrohevetikate esinemissagedus. Tööst selgus, et antropogeensest eutrofeerumisest tingitud rooalade laienemine on vähendanud eulitoraalis väikesekasvulistele liikidele sobivaid elupaiku. Kaldaalade kinnikasvamine on suurendanud kohalike elanike vajadust rannaalade majandamiseks. Üldiselt võib tihedate pillirookogumike eemaldamist pidada taimestiku liigirikkusele positiivseks, kuid vältida tuleks monotoonsete ja kuivade „terrassistatud“ (kõrgendatud) alade kujundamist. Suurim liigirikkus oli iseloomulik rannalõikudele, kus niidetud ja majandamata elupaigad vaheldusid ning ei olnud terrassistatud ala. Veetaseme kõikumine Peipsis on käsitletav keskmise häiringuna, mis toetab liigirikkuse säilimist elupaikade suurenenud mosaiiksuse ning liikidele uute niššide kujunemise tõttu. Veetaseme langusega paljanduvad elupaigad, mis on sobivad väheneva levikuga liikidele, nagu näiteks väike konnarohi, kaartulikas ja pruun lõikhein. Madalveeperioodil tõusis märgatavalt liigirikkus ning head seisundit näitavate veesiseste taimede ja mändvetikate ohtrus, aga samas ka kesist seisundit peegeldavate suurte niitrohevetikate ohtrus. Kuna uuring näitas liikide esinemise ning ohtruse väga tugevat sõltuvust veetaseme muutustest, siis on ilmne, et veekogu ökoloogilise seisundi hinnang on sellest looduslikust häiringufaktorist märkimisväärselt mõjutatud.Publication of this thesis is supported by the Estonian University of Life Science

Response of primary producers to water level fluctuations of Lake Peipsi

The amplitude of natural fluctuation between annual averages of the water level (WL) of Lake Peipsi (3555 km 2) is 1.5 m. A study aimed to examine the impact of WL fluctuations on phytoplankton, macrophytes, and their epiphyton was performed annually at littoral stations during 2005–2015. Also the characteristics of pelagic water were collated with the WL. Changes in littoral and pelagial phytoplankton were similar, with the exclusion of massive wind-caused accumulations of cyanobacteria in the littoral. At the lowest WL a significant increase occurred in (a) the biomass of phytoplankton and the share of phytoplankton-derived organic carbon in water and (b) the species richness and biomass of macrophytes, including submerged plants and macroalgae. The abundance of epiphytes did not reveal a clear relation with the WL. The ratios of biomasses in the years with the lowest and the highest average WL were 2.2 for Potamogeton spp. and 2.6 for phytoplankton. The assessment of ecological status at the minimum and the maximum WL differs at least by one quality class. Decisions about ecological status based on phytoplankton and large filamentous green algae at low water may be contrary to decisions based on macrophytes: high biomasses of phytoplankton and macroalgae indicate hypertrophic status, but species-rich macrovegetation and high biomasses of charophytes and elodeids are considered to be characteristic of meso- to eutrophic water bodies.This study was supported by the Estonian Target Financed Project SF0362483s03, by the Estonian State Monitoring Programme, and by the materials of the herbarium of the Department of Botany in the Institute of Agricultural and Environmental Sciences of the Estonian University of Life Sciences.This study was supported by the Estonian Target Financed Project SF0362483s03, by the Estonian State Monitoring Programme, and by the materials of the herbarium of the Department of Botany in the Institute of Agricultural and Environmental Sciences of the Estonian University of Life Sciences

Macrophyte data of Lake Peipsi

Macrophyte data of Lake Peipsi has been collected from ten different stations (locations with coordinates in the dataset) starting from 2005, during the Estonian National Monitoring of Environment. Species composition and abundances were registered on the transects starting from upper boundary of the temporarily flooded zone to the deepest growth zone. The width of the transect was ca 20 meters on the shore and near the water´s edge and ca 10 m in deeper water. The abundance was estimated on a 1-5-point scale: 1 - single plant or few plants; 2 - scattered plants or some small stands; 3 - numerous, frequent in the observation area; 4 - dominant or codominant; 5 - mass occurrence, absolute dominant (Mäemets et al., 2010). Taxon ID originates from the database: https://www.freshwaterecology.info (according Schmidt-Kloiber, A. & Hering, D., 2015; 2022). For some taxa with more eastern distribution ID was lacking in this database.ReferencesMäemets, H., Palmik, K., Sudnitsyna, D. & Melnik, M. (2010) Eutrophication and macrophyte species richness in the large shallow North-European Lake Peipsi. Aquatic Botany 92:273-280.Schmidt-Kloiber, A. & Hering D. (2015): www.freshwaterecology.info - an online tool that unifies, standardises and codifies more than 20,000 European freshwater organisms and their ecological preferences. Ecological Indicators 53: 271-282. doi: 10.1016/j.ecolind.2015.02.007Schmidt-Kloiber A. & Hering D. (eds.): www.freshwaterecology.info - the taxa and autecology database for freshwater organisms, version 8.0 (accessed on 22.11.2022)

Outcomes of the littoral monitoring of a large shallow lake: a case of Lake Peipsi : [presentation]

The presentation took place at the 11th International Shallow Lakes Conference.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 951963, and was supported by the Estonian State Monitoring Programme.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 951963, and was supported by the Estonian State Monitoring Programme

Lake Peipsi 2022 (Phytoplankton samples)

Method: Phytoplankton samples were preserved in Lugol’s (acidified iodine) solution and counted under an inverted microscope (Utermöhl, 1958). 3-10 ml of preserved sample was settled overnight and counted in random fields or transects. Biovolumes of algal cells, colonies and/or filaments were calculated using assigned geometric shapes dimensions, and converted to biomass assuming the specific density of 1 g cm-3 in accordance with Edler (1979). Approved by CEN on 14 July 2006 “Water quality - Guidance standard on the enumeration of phytoplankton using inverted microscopy (Utermöhl technique)” (CEN 15204, 2006) European Standard EN 15204:2006 Utermöhl, H., 1958. Zur Vervollkommnung der quantitativen Phytoplankton-Methodik. Mitteilungen der Internationale Vereinigung für Theoretische und Angewandte Limnologie 9, 1- 38. Edler, L. (ed.), 1979. Recommendations on methods for marine biological studies in the Baltic Sea. Phytoplankton and chlorophyll. Baltic Marine Biologists WG 9. Leg: K. Blank, K. Palmik-Das, L. Tuvikene, A. Tuvikene; det: K. Maileht

Lake Peipsi 2021 (Phytoplankton samples)

Method: Phytoplankton samples were preserved in Lugol’s (acidified iodine) solution and counted under an inverted microscope (Utermöhl, 1958). 3-10 ml of preserved sample was settled overnight and counted in random fields or transects. Biovolumes of algal cells, colonies and/or filaments were calculated using assigned geometric shapes dimensions, and converted to biomass assuming the specific density of 1 g cm-3 in accordance with Edler (1979). Approved by CEN on 14 July 2006 “Water quality - Guidance standard on the enumeration of phytoplankton using inverted microscopy (Utermöhl technique)” (CEN 15204, 2006) European Standard EN 15204:2006 Utermöhl, H., 1958. Zur Vervollkommnung der quantitativen Phytoplankton-Methodik. Mitteilungen der Internationale Vereinigung für Theoretische und Angewandte Limnologie 9, 1- 38. Edler, L. (ed.), 1979. Recommendations on methods for marine biological studies in the Baltic Sea. Phytoplankton and chlorophyll. Baltic Marine Biologists WG 9. Leg: K. Blank, K. Palmik-Das, L. Tuvikene, A. Tuvikene; det: K. Maileht

Lake Peipsi 2014 (Littoral samples)

Phytoplankton samples were picked with bottle from among reed stands or from above thick beds of submerged plants from the depth 20-30 cm, were preserved in Lugol’s (acidified iodine) solution and counted under an inverted microscope (Utermöhl, 1958). 3 ml of preserved sample was settled overnight and counted in random fields or transects. Biovolumes of algal cells, colonies and/or filaments were calculated using assigned geometric shapes dimensions, and converted to biomass assuming the specific density of 1 g cm-3 in accordance with Edler (1979). Macroscopic colonies of Gloeotrichia echinulata were enumerated visually in 500 ml measuring cylinder. Counting units are independent (single) algal cells, colonies or filaments/trichomes. One species or taxon may be present in the sample as different counting units and may be counted at different magnifications. References of methods accepted Approved by CEN on 14 July 2006 “Water quality - Guidance standard on the enumeration of phytoplankton using inverted microscopy (Utermöhl technique)” (CEN 15204, 2006) European Standard EN 15204:2006 Utermöhl, H., 1958. Zur Vervollkommnung der quantitativen Phytoplankton-Methodik. Mitteilungen der Internationale Vereinigung für Theoretische und Angewandte Limnologie 9, 1-38. Edler, L. (ed.), 1979. Recommendations on methods for marine biological studies in the Baltic Sea. Phytoplankton and chlorophyll. Baltic Marine Biologists WG 9. (13) Biovolume calculation for pelagic and benthic microalgae | Request PDF. Available from: https://www.researchgate.net/publication/220031275_Biovolume_calculation_for_pelagic_and_benthic_microalgae [accessed Oct 29 2018]. The most commonly used traditional biomass estimate for microalgae is cell biovolume, which is calculated from microscopically measured linear dimensions (Steinman et al. 1991, Snoeijs 1994, Sommer 1994, 1995, Hillebrand and Sommer 1997). Hand-books, most representative Huber-Pestalozzi, G., Komarek, J., Fott, B. 1983. Das Phytoplankton des Süsswassers. 7(1). Chlorophyceae. Chlorococcales. Stuttgart. 1044. S. Komarek, J., Anagnostidis, K. 1999. Süsswasserflora von Mitteleuropa. 19/1. Cyanoprocaryota. 1. Chroococcales. Elsevier Spectrum Academischer Verlag. Heidelberg. Berlin. 548 S. Komarek, J., Anagnostidis, K. 2005. Süsswasserflora von Mitteleuropa. 19/2. Cyanoprocaryota. 2. Oscillatoriales. Elsevier Spectrum Academischer Verlag. 759 S. Komárek, J., 2013. Cyanoprokaryota 3. Teil: Heterocystous Genera. Süsswasserflora von Mitteleuropa. B. 19/3. Springer Spektrum. 1130 S. Krammer, K., Lange-Bertalot, H. 1997-1991. Süsswasserflora von Mitteleuropa. Bacillariophyceae. B. 2, 1-4. Spectrum Academischer Verlag.Heidelberg. Berlin.. Popovský, J., Pfiester, L.A. 20008. Dinophyceae (Dinoflagellida). Süsswasserflora von Mitteleuropa. B. 6. Springer Spektrum. 272 S. Косинская Е.К. 1960. Флора споровых растений СССР. Том 5. Конъюгаты и Сцеплянки. (2). Изд. АН СССР. Москва-Ленинград. 706 стр. In Russian. Korshikov, A.A. (1953). Viznachnik prisnovodnikh vodorosley Ukrainsykoi RSR [Vyp] V. Pidklas Protokokovi (Protococcineae). Bakuol'ni (Vacuolales) ta Protokokovi (Protococcales) [The Freshwater Algae of the Ukrainian SSR. V. Sub-Class Protococcineae. Vacuolales and Protococcales]. pp. 1-439. Kyjv [Kiev]: Akad. NAUK URSR. In Ukrainian. Матвiенко О.М. 1965. Визначник прiсноводных водоростей Украǐнской РСР. 3. Частина 1. Золотисти водорости – Chrysophyta. Изд. Наукова Думка. Киǐв. 367 стр. In Ukrainian. Попова Т.Г. 1955. Определитель пресноводных водорослей. Вып. 7. Эвгленовые водоросли. Изд. Советская Наука, Москва. 282 стр. In Russian

Lake Peipsi 2005 (Phytoplankton samples) 

DatasetMethod: Phytoplankton samples were preserved in Lugol’s (acidified iodine) solution and counted under an inverted microscope (Utermöhl, 1958). 3 ml of preserved sample was settled overnight and counted in random fields or transects. Biovolumes of algal cells, colonies and/or filaments were calculated using assigned geometric shapes dimensions, and converted to biomass assuming the specific density of 1 g cm-3 in accordance with Edler (1979). Approved by CEN on 14 July 2006 “Water quality - Guidance standard on the enumeration of phytoplankton using inverted microscopy (Utermöhl technique)” (CEN 15204, 2006) European Standard EN 15204:2006 Utermöhl, H., 1958. Zur Vervollkommnung der quantitativen Phytoplankton-Methodik. Mitteilungen der Internationale Vereinigung für Theoretische und Angewandte Limnologie 9, 1- 38. Edler, L. (ed.), 1979. Recommendations on methods for marine biological studies in the Baltic Sea. Phytoplankton and chlorophyll. Baltic Marine Biologists WG 9

Lake Peipsi 2013 (Littoral samples)

Phytoplankton samples were picked with bottle from among reed stands or from above thick beds of submerged plants from the depth 20-30 cm, were preserved in Lugol’s (acidified iodine) solution and counted under an inverted microscope (Utermöhl, 1958). 3 ml of preserved sample was settled overnight and counted in random fields or transects. Biovolumes of algal cells, colonies and/or filaments were calculated using assigned geometric shapes dimensions, and converted to biomass assuming the specific density of 1 g cm-3 in accordance with Edler (1979). Macroscopic colonies of Gloeotrichia echinulata were enumerated visually in 500 ml measuring cylinder. Counting units are independent (single) algal cells, colonies or filaments/trichomes. One species or taxon may be present in the sample as different counting units and may be counted at different magnifications. References of methods accepted Approved by CEN on 14 July 2006 “Water quality - Guidance standard on the enumeration of phytoplankton using inverted microscopy (Utermöhl technique)” (CEN 15204, 2006) European Standard EN 15204:2006 Utermöhl, H., 1958. Zur Vervollkommnung der quantitativen Phytoplankton-Methodik. Mitteilungen der Internationale Vereinigung für Theoretische und Angewandte Limnologie 9, 1-38. Edler, L. (ed.), 1979. Recommendations on methods for marine biological studies in the Baltic Sea. Phytoplankton and chlorophyll. Baltic Marine Biologists WG 9. (13) Biovolume calculation for pelagic and benthic microalgae | Request PDF. Available from: https://www.researchgate.net/publication/220031275_Biovolume_calculation_for_pelagic_and_benthic_microalgae [accessed Oct 29 2018]. The most commonly used traditional biomass estimate for microalgae is cell biovolume, which is calculated from microscopically measured linear dimensions (Steinman et al. 1991, Snoeijs 1994, Sommer 1994, 1995, Hillebrand and Sommer 1997). Hand-books, most representative Huber-Pestalozzi, G., Komarek, J., Fott, B. 1983. Das Phytoplankton des Süsswassers. 7(1). Chlorophyceae. Chlorococcales. Stuttgart. 1044. S. Komarek, J., Anagnostidis, K. 1999. Süsswasserflora von Mitteleuropa. 19/1. Cyanoprocaryota. 1. Chroococcales. Elsevier Spectrum Academischer Verlag. Heidelberg. Berlin. 548 S. Komarek, J., Anagnostidis, K. 2005. Süsswasserflora von Mitteleuropa. 19/2. Cyanoprocaryota. 2. Oscillatoriales. Elsevier Spectrum Academischer Verlag. 759 S. Komárek, J., 2013. Cyanoprokaryota 3. Teil: Heterocystous Genera. Süsswasserflora von Mitteleuropa. B. 19/3. Springer Spektrum. 1130 S. Krammer, K., Lange-Bertalot, H. 1997-1991. Süsswasserflora von Mitteleuropa. Bacillariophyceae. B. 2, 1-4. Spectrum Academischer Verlag.Heidelberg. Berlin.. Popovský, J., Pfiester, L.A. 20008. Dinophyceae (Dinoflagellida). Süsswasserflora von Mitteleuropa. B. 6. Springer Spektrum. 272 S. Косинская Е.К. 1960. Флора споровых растений СССР. Том 5. Конъюгаты и Сцеплянки. (2). Изд. АН СССР. Москва-Ленинград. 706 стр. In Russian. Korshikov, A.A. (1953). Viznachnik prisnovodnikh vodorosley Ukrainsykoi RSR [Vyp] V. Pidklas Protokokovi (Protococcineae). Bakuol'ni (Vacuolales) ta Protokokovi (Protococcales) [The Freshwater Algae of the Ukrainian SSR. V. Sub-Class Protococcineae. Vacuolales and Protococcales]. pp. 1-439. Kyjv [Kiev]: Akad. NAUK URSR. In Ukrainian. Матвiенко О.М. 1965. Визначник прiсноводных водоростей Украǐнской РСР. 3. Частина 1. Золотисти водорости – Chrysophyta. Изд. Наукова Думка. Киǐв. 367 стр. In Ukrainian. Попова Т.Г. 1955. Определитель пресноводных водорослей. Вып. 7. Эвгленовые водоросли. Изд. Советская Наука, Москва. 282 стр. In Russian