Sirvi Autor "Tuvikene, Lea" järgi

Nüüd näidatakse 1 - 20 21

Climate change affects lakes. What can we do?: Policy brief, June 26, 2023
(Estonian University of Life Sciences, 2023) Tuvikene, Lea; Nõges, Peeter
✓ Lake ecosystems provide vital services for humanity, but, due to global climate change, the quality and quantity of these services is decreasing. ✓ Lakes supply us with clean water and fish, they regulate nutrient cycling and modify climate change effects by controlling floods and the amount of CO2, which is the main cause of climate warming. In an urbanizing world, the aesthetic and recreational importance of lakes for human well-being is increasing. ✓ Changes in temperature, precipitation and wind affect lake levels and water availability, alter the distribution of oxygen and nutrients, and impact the survival and abundance of aquatic organisms: algal blooms expand causing massive fish kills. ✓ Understanding these mutual interactions through improved climate models, monitoring of water quality, and assessing ecosystem health is crucial for managing and mitigating the impacts of climate change on lakes. ✓ As the impact of eutrophication and climate change follow the same pathways affecting nutrient availability and cascading effects in the food web, establishing stricter control over anthropogenic nutrient loading is the most efficient adaptive strategy to preserve the ecological integrity of lakes and the services they provide.
Cross border cooperation on environmental monitoring of Lake Peipsi: main results and perspectives : [presentation]
(Estonian University of Life Sciences, 2021) Tuvikene, Lea; Tammeorg, Olga; Nõges, Peeter; Nõges, Tiina
The presentation took place at the Lahti Lakes 2021 Symposium.
Data Descriptor : A European Multi Lake Survey dataset of environmental variables, phytoplankton pigments and cyanotoxins
(Springer Nature, 2018) Mantzouki, Evanthia; Campbell, James; Van Loon, Emiel; Visser, Petra; Konstantinou, Iosif; Antoniou, Maria; Giuliani, Grégory; Machado-Vieira, Danielle; Gurjão de Oliveira, Alinne; Maronić, Dubravka Špoljarić; Stević, Filip; Pfeiffer, Tanja Žuna; Vucelić, Itana Bokan; Žutinić, Petar; Udovič, Marija Gligora; Plenković-Moraj, Anđelka; Tsiarta, Nikoletta; Bláha, Luděk; Geriš, Rodan; Fránková, Markéta; Christoffersen, Kirsten Seestern; Warming, Trine Perlt; Feldmann, Tõnu; Laas, Alo; Panksep, Kristel; Tuvikene, Lea; Kangro, Kersti; Häggqvist, Kerstin; Salmi, Pauliina; Arvola, Lauri; Fastner, Jutta; Straile, Dietmar; Rothhaupt, Karl-Otto; Fonvielle, Jeremy; Grossart, Hans-Peter; Avagianos, Christos; Kaloudis, Triantafyllos; Triantis, Theodoros; Zervou, Sevasti-Kiriaki; Hiskia, Anastasia; Gkelis, Spyros; Panou, Manthos; McCarthy, Valerie; Perello, Victor C.; Obertegger, Ulrike; Boscaini, Adriano; Flaim, Giovanna; Salmaso, Nico; Cerasino, Leonardo; Koreivienė, Judita; Karosienė, Jūratė; Kasperovičienė, Jūratė; Savadova, Ksenija; Vitonytė, Irma; Haande, Sigrid; Skjelbred, Birger; Grabowska, Magdalena; Karpowicz, Maciej; Chmura, Damian; Nawrocka, Lidia; Kobos, Justyna; Mazur-Marzec, Hanna; Alcaraz-Párraga, Pablo; Wilk-Woźniak, Elżbieta; Krztoń, Wojciech; Walusiak, Edward; Gagala, Ilona; Mankiewicz-Boczek, Joana; Toporowska, Magdalena; Pawlik-Skowronska, Barbara; Niedźwiecki, Michał; Pęczuła, Wojciech; Napiórkowska-Krzebietke, Agnieszka; Dunalska, Julita; Sieńska, Justyna; Szymański, Daniel; Kruk, Marek; Budzyńska, Agnieszka; Goldyn, Ryszard; Kozak, Anna; Rosińska, Joanna; Szeląg-Wasielewska, Elżbieta; Domek, Piotr; Jakubowska-Krepska, Natalia; Kwasizur, Kinga; Messyasz, Beata; Pełechata, Aleksandra; Pełechaty, Mariusz; Kokocinski, Mikolaj; Madrecka, Beata; Kostrzewska-Szlakowska, Iwona; Frąk, Magdalena; Bańkowska-Sobczak, Agnieszka; Wasilewicz, Michał; Ochocka, Agnieszka; Pasztaleniec, Agnieszka; Jasser, Iwona; Antão-Geraldes, Ana M.; Leira, Manel; Hernández, Armand; Vasconcelos, Vitor; Morais, João; Vale, Micaela; Raposeiro, Pedro M.; Gonçalves, Vítor; Aleksovski, Boris; Krstić, Svetislav; Nemova, Hana; Drastichova, Iveta; Chomova, Lucia; Remec-Rekar, Spela; Elersek, Tina; Delgado-Martín, Jordi; García, David; Cereijo, Jose Luís; Gomà, Joan; Trapote, Mari Carmen; Vegas-Vilarrúbia, Teresa; Obrador, Biel; García-Murcia, Ana; Real, Monserrat; Romans, Elvira; Noguero-Ribes, Jordi; Duque, David Parreño; Fernández-Morán, Elísabeth; Úbeda, Bárbara; Gálvez, José Ángel; Marcé, Rafael; Catalán, Núria; Pérez-Martínez, Carmen; Ramos-Rodríguez, Eloísa; Cillero-Castro, Carmen; Moreno-Ostos, Enrique; Blanco, José María; Rodríguez, Valeriano; Montes-Pérez, Jorge Juan; Palomino, Roberto L.; Rodríguez-Pérez, Estela; Carballeira, Rafael; Camacho, Antonio; Picazo, Antonio; Rochera, Carlos; Santamans, Anna C.; Ferriol, Carmen; Romo, Susana; Soria, Juan Miguel; Hansson, Lars-Anders; Urrutia-Cordero, Pablo; Özen, Arda; Bravo, Andrea G.; Buck, Moritz; Colom-Montero, William; Mustonen, Kristiina; Pierson, Don; Yang, Yang; M. H. Verspagen, Jolanda; De Senerpont Domis, Lisette N.; Seelen, Laura; Teurlincx, Sven; Verstijnen, Yvon; Lürling, Miquel; Maliaka, Valentini; Faassen, Elisabeth J.; Latour, Delphine; Carey, Cayelan C.; W. Paerl, Hans; Torokne, Andrea; Karan, Tünay; Demir, Nilsun; Beklioğlu, Meryem; Filiz, Nur; E. Levi, Eti; Iskin, Uğur; Bezirci, Gizem; Tavşanoğlu, Ülkü Nihan; Çelik, Kemal; Özhan, Koray; Karakaya, Nusret; Koçer, Mehmet Ali Turan; Yilmaz, Mete; Maraşlıoğlu, Faruk; Fakioglu, Özden; Soylu, Elif Neyran; Yağcı, Meral Apaydın; Çınar, Şakir; Çapkın, Kadir; Yağcı, Abdulkadir; Cesur, Mehmet; Bilgin, Fuat; Bulut, Cafer; Uysal, Rahmi; Köker, Latife; Akçaalan, Reyhan; Albay, Meriç; Alp, Mehmet Tahir; Özkan, Korhan; Sevindik, Tuğba Ongun; Tunca, Hatice; Önem, Burçin; Richardson, Jessica; Edwards, Christine; Bergkemper, Victoria; O'Leary, Sarah; Beirne, Eilish; Cromie, Hannah; Ibelings, Bastiaan W.; Institute of Agricultural and Environmental Sciences
Under ongoing climate change and increasing anthropogenic activity, which continuously challenge ecosystem resilience, an in-depth understanding of ecological processes is urgently needed. Lakes, as providers of numerous ecosystem services, face multiple stressors that threaten their functioning. Harmful cyanobacterial blooms are a persistent problem resulting from nutrient pollution and climate-change induced stressors, like poor transparency, increased water temperature and enhanced stratification. Consistency in data collection and analysis methods is necessary to achieve fully comparable datasets and for statistical validity, avoiding issues linked to disparate data sources. The European Multi Lake Survey (EMLS) in summer 2015 was an initiative among scientists from 27 countries to collect and analyse lake physical, chemical and biological variables in a fully standardized manner. This database includes in-situ lake variables along with nutrient, pigment and cyanotoxin data of 369 lakes in Europe, which were centrally analysed in dedicated laboratories. Publishing the EMLS methods and dataset might inspire similar initiatives to study across large geographic areas that will contribute to better understanding lake responses in a changing environment.
The effect of natural variability on the assessment of ecological status of shallow lakes
(Eesti Maaülikool, 2018) Tuvikene, Lea; Nõges, Peeter (advisor); Nixdorf, Brigitte (opponent); Ercoli, Fabio (pre-opponent)
The dissertation contributes to the improvement of large lake monitoring, demonstrating that besides following the class boundaries of ecological status established by law, reliable status estimates of such lakes require profound expert knowledge on ecosystem functioning, and considering the share of natural and human induced factors influencing the ecosystem. WFD defines the status of water bodies by the extent of anthropogenic deviation from the reference conditions, i.e. conditions that should occur at sites of any particular type in the absence of human impact. Ecological status of Estonian large, shallow lakes Peipsi and Võrtsjärv is greatly influenced by direct human activities as well as climate change. For example, the trend of water brownification influencing the whole matter circulation of lakes, results from natural hydrological processes, but also from decreasing atmospheric sulphur deposition – both determining the mobility of humic substances. It is a complicated task to find simple, well-functioning indicators to assess ecological status of water bodies which are influenced by natural factors, such as large water level fluctuations and strong seasonality, more than by human impact. For example, for Lake Võrtsjärv, all common water quality indicators show worse ecological status in periods of low water level despite unchanged human impact. It should also be considered that the influence of changed environmental conditions may become evident with a time lag – after one or even several years. In Lake Võrtsjärv, changes in water surface temperature and water level explain approximately one half of the total changes in values of ecological status indicators. The reliability of status estimates can be significantly increased by statistically correcting the values of status indicators for factors causing natural variability. Analysis of spatial variability of status indicators in Lake Võrtsjärv showed that the permanent sampling station at the deepest site of the lake is representative for more than 90% of the lake area. To improve cost-effectiveness of the state monitoring programme, this sampling site remains the only open water monitoring site at the lake since 2017.
Factors controlling the three-decade long rise in cyanobacteria biomass in a eutrophic shallow lake
(Elsevier, 2018) Cremona, Fabien; Tuvikene, Lea; Haberman, Juta; Nõges, Peeter; Nõges, Tiina; Centre for Limnology. Institute of Agricultural and Environmental Sciences. Estonian University of Life Sciences
We aimed at quantifying the importance of limnological variables in the decadal rise of cyanobacteria biomass in shallow hemiboreal lakes. We constructed estimates of cyanobacteria (blue-green algae) biomass in a large, eutrophic lake (Estonia, Northeastern Europe) from a database comprising 28 limnological variables and spanning more than 50 years of monitoring. Using a dual-model approach consisting in a boosted regression trees (BRT) followed by a generalized least squares (GLS) model, our results revealed that six variables were most influential for assessing the variance of cyanobacteria biomass. Cyanobacteria response to nitrate concentration and rotifer abundance was negative, whereas it was positive to pH, temperature, cladoceran and copepod biomass. Response to total phosphorus (TP) and total phosphorus to total nitrogen ratio was very weak, which suggests that actual in-lake TP concentration is still above limiting values. The most efficient GLS model, which explained nearly two thirds (r2 = 0.65) of the variance of cyanobacteria biomass included nitrate concentration, water temperature and pH. The very high number of observations (maximum n = 525) supports the robustness of the models. Our results suggest that the decadal rise of blue-green algae in shallow lakes lies in the interaction between cultural eutrophication and global warming which bring in-lake physical and chemical conditions closer to cyanobacteria optima.
A Future Tale of Two Winters? Sediment-water interface nitrogen dynamics in Lake Võrtsjärv (Estonia) during the ice-free winter 2019/2020 : [presentation]
(Estonian University of Life Sciences, 2021) McCarthy, Mark J.; Newell, Silvia; Tuvikene, Lea; Sepp, Margot; Tamm, Marju; Zingel, Priit; Feldmann, Tõnu; Olli, Kalle; Nõges, Tiina
The presentation took place at the Lahti Lakes 2021 Symposium.
Improving administrative effectiveness of lake management in the frames of River Basin Management Plans : Implementation Plan
(2014) Tuvikene, Lea; Sammalkorpi, Ilkka; Kreitsberg, Randel; Soo, Kristjan; Tuvikene, Arvo; Estonian University of Life Sciences
Fresh waters make only 3% of the global water resources. Freshwater lakes, including reservoirs and ponds, are important elements for communities and their relevance is increasing. Lake ecosystems and their catchments have provided several societally valuable benefits and ecosystem services like shelter, drinking water, bathing water, food, a means of travel and wealth in a number of ways and allowed whole cultures to develop. Lakes have values associated with well-being and relaxation, their proximity has catalyzed rural development and been important in the regional socio-economic development. Lake districts are often very popular destinations for domestic and foreign tourism and visitors. Eutrophication and its ecological consequences, pollution, over abstraction and invasive species are serious threats and increase the need for restoration and management to prevent the potential adverse economic and social impacts. There is increasing evidence that lakes are affected by climate change. Lake management is for these reasons an important part of sustainable regional development as set by Lisbon and Gothenburg agreements. However, the most significant piece of legislation in response to the increasing threat of pollution and the increasing demand from the public for cleaner lakes, rivers and beaches and freshwater biodiversity, is the EU Water Framework Directive (WFD). This Directive is unique in that it sets out an established framework for the protection of all water bodies (including lakes) and for all EU member states to achieve good water ecological status by December 2015. This objective is likely to be achieved in slightly over half (53 %) of EU waters (A blueprint…, 2013) and, therefore, more effort need to be scheduled for the following 6-year periods of WFD. The economic values of attractive, clean lakes are well established. There is a rising appreciation of good quality lakes across Europe. More intensive lake protection through sharing good practices with European lake managers and the regional influencing bodies is critical if we want to improve the current quality of lakes in Europe and to build long term capacity for sustainable use of lakes.
Is fish biomass controlled by abiotic or biotic factors? Results of long- term monitoring in a large eutrophic lake
(Elsevier, 2020) Öglü, Burak; Bhele, Upendra; Järvalt, Ain; Tuvikene, Lea; Timm, Henn; Seller, Siim; Haberman, Juta; Agasild, Helen; Nõges, Peeter; Silm, Maidu; Bernotas, Priit; Nõges, Tiina; Cremona, Fabien; Chair of Hydrobiology and Fishery. Institute of Agricultural and Environmental Sciences.
Relationships between biomass and ecological factors including trophic interactions were examined to understand the dynamics of six fish species in Lake Võrtsjärv, a large shallow eutrophic lake located in Estonia (north-eastern Europe). The database contained initially 31 predictive variables that were monitored in situ for nearly forty years. The strongest predictive variables were selected by three parallel approaches: single correlation (Pearson), a multivariate method (Co-inertia analyses), and a machine learning algorithm (Random Forests), followed by a Generalized Least Squares model to determine meaningful relationships with fish biomass. Models with both additive and interactive effects were constructed. The results revealed that the indicators of degraded ecological conditions (high cyanobacteria biomass and their proportion in total phytoplankton, high summer temperature, high nutrient concentration) were negatively correlated to fish biomass. Benthic macroinvertebrates and other biotic predictors (biomass of specific fish prey and predators) were also important contributors to fish biomass dynamics. Together, abiotic and biotic factors explained 40–60% of the variance of fish biomass, depending of the species. Our findings suggest that both abiotic and biotic factors control fish biomass changes in this eutrophic lake.
Järvede haldamine vesikondade veemajanduskavade raames : tegevuskava
(2014) Tuvikene, Lea; Sammalkorpi, Ilkka; Kreitsberg, Randel; Soo, Kristjan; Tuvikene, Arvo (koostaja); Eesti Maaülikool
Vaata ka EMU DSpace'is Viitna Pikkjärve, Veisjärve, Verevi järve ja Harku järve meetmekavasid.
Järvede tervendamine. Kogumik
(2011) Kõiv, Toomas; Ott, Ingmar; Tuvikene, Lea; Sarik, Diana; Panksep, Kristel; Pedusaar, Tiia; Järvalt, Ain; Tuvikene, Arvo; Mäemets, Helle; Timm, Henn; Kisand, Anu; Mugra, Tõnu; Laanetu, Nikolai; Tupits, Ilmar; Laas, Alo; Sammalkorpi, Ilkka; Hamilton, David P.; Eesti Maaülikool. Põllumajandus- ja keskkonnainstituut. Limnoloogiakeskus
Eessõna järvede tervendamise käsiraamatule Kui veel 1950 – 60-ndatel aastatel võis enamiku Eesti järvede seisundit pidada looduslikuks, siis 21. sajandi alguseks on paljude järvede seisund peamiselt tugeva inimmõju tagajärjel märkimisväärselt halvenenud. Hinnanguliselt 10 – 12% meie järvedest on halvas seisundiklassis ja vajaks kindlasti tervendamist. Lisaks on veel palju järvi , mille seisund ei ole küll päris halb, aga vajab siiski parandamist. Euroopa Liidus 2000. aastal rakendunud veepoliitika raamdirektiiv seab eesmärgiks saavutada aastaks 2015 liikmesriikide kõigi vete, sh pinnavee, põhjavee, reovee ja joogivee, hea seisund. Pinnaveekogudes tuleb lisaks vee heale keemilisele seisundile saavutada ka hea ökoloogiline seisund. Kui veekogu seisund pole hinnatud heaks või väga heaks, tuleb kasutusele võtta meetmed vähemalt hea seisundi saavutamiseks. Selleks võib olla piisav veekogu majandamise ümberkorraldamine, kuid enamasti tähendab see vajadust astuda konkreetseid samme valgalalt saabuva reostuskoormuse vähendamiseks ja ka veekogu enese tervendamiseks. Järvede kui suure loodusväärtuse hea seisund on oluline ka inimese tervise seisukohast. Terved ja kaunid järved pakuvad puhkamiseks ja töövõime taastamiseks mitmekülgseid võimalusi, mille hulgas on kalastamine kindlasti üks märkimisväärsemaid. Keskkonnaministeeriumi korraldatud küsitlusel harrastuspüüdjate seas selgus, et enim häirivad hobikalureid veekogudele ligipääsu puudumine ja väike vääriskalavaru, kuid ka veekogude halb olukord ja üldine kala vähesus. Tervendamine võimaldab lisaks järvede olukorra parandamisele tervikuna taastada või tõsta ka nende kalamajanduslikku väärtust. Nagu igal elualal, on ka järvede tervendamise alases sõnavaras kasutusel palju sama või osaliselt kattuva tähendusega mõisteid. Levinuim vaste järvede tervendamisele on olnud „restaureerimine” , mis on eesti keelde tulnud ingliskeelsest mõistest restoration , otsetõlkena on palju kasutatud ka „taastamist”. Võõrsõna ja selle sisult ebatäpsete eestikeelsete vastete asemel on järveteadlased üsna edukalt suutnud juurutada hoopis kodusema kõlaga ja pehmema sisuga mõistet „tervendamine”. Käsiraamatu esimeses peatükis soovitatakse tervendamise terminoloogiat vastavalt sellele, kui põhjalikku sekkumist on järve seisundi parandamiseks vaja. Seal leiab käsitlemist tervendamise kitsam tähendus. Nii selle käsiraamatu pealkirjas kui tekstis kasutame enamasti seda mõistet laiemas tähenduses, mis hõlmab kõiki järvede olukorra parandamisega seotud tegevusi ja viise olenemata sellest, kui põhjalikke muutusi läbi viiakse. Eestis jõudsalt hoogu koguv järvede tervendamine on seni põhinenud üsna lünklikel ja juhuslikel teadmistel, kuna meil on puudunud seda teemat tervikuna ja põhjalikult käsitlev eestikeelne kirjandus. Heal juhul on järvede tervendajad leidnud üles järveteadlased ja lasknud enne järve kallale asumist teha uuringud, saamaks teada, mis on järve seisundi halvenemise tegelikud põhjused. Keskkonnainvesteeringute Keskuse toel Eesti Maaülikoolis valminud artiklite kogum on „Järvede tervendamise käsiraamatu” käsikiri, mis vajab enne päris raamatuks saamist veel toimetamist. Kuna vajadus sellise juhend- ja õppematerjali järele on suur, siis on käsikirjalised artiklid juba avalikult kättesaadavaks tehtud. Esimene peatükk tutvustab järveteaduse ehk limnoloogia aluseid, mis aitavad mõista järvede tervendamise põhimõtteid. Teises peatükis antakse ülevaade Eesti järvede tervendamisvajadusest. Kolmas peatükk käsitleb kogu tervendamisega kaasnevat protsessi, alates idee tekkimisest ja asja kohasest seadusandlusest ning lõpetades järelseirega. Järgnevad peatükid käsitlevad tervendamise meetodeid: biomanipulatsioon (peatükk 4), vee hapnikuga rikastamine (peatükk 5) , veerežiimi muutmine (peatükk 6) , makrofüüdijärvede tervendamine (peatükk 7), vee ja setete keemilise töötlemise meetodid (peatükk 8) ja setete eemaldamine (peatükk 9). Peatükk 10 tutvustab järve veetaseme tõstmise ja sette eemaldamise ehitusprojektidega seonduvat. Peatükis 11 leiavad käsitlemist keskkonnamõjude hindamine ja järvede hooldus. Kuigi näiteid järvede tervendamisest leidub igas konkreetseid meetodeid käsitlevas peatükis, annab viimane, 12. peatükk veel ülevaate veekogude tervendamise senistest kogemustest Eestis ja mujal Euroopas ning kirjeldab põhjalikumalt mõnd huvitavamat tervendamise näidet nii meilt kui mujalt maa ilmast. Käsikirja autorid loodavad, et kirjapandust on abi järvede tervendamisega seotud inimestele ja lõppkokkuvõttes meie paljude järvede tervisele. Kõik täiendused, parandused ja ettepanekud, mis võiksid kaasa aidata sisuka ja kasuliku käsiraamatu valmimisele, on teretulnud aadressile: Lea Tuvikene, Limnoloogiakeskus, Rannu 61117, Tartumaa , või e - posti aadressile lea.tuvikene@emu.ee
Järveteadlased - mis neist kasu? : [esitlus]
(Eesti Maaülikool, 2023) Tuvikene, Lea
Esitlus toimus 25. augustil, 2023 Järvemuuseumi üritusel “Võrtsjärve peegeldus.”
Keystone species Chydorus sphaericus in shallow eutrophic Lake Võrtsjärv (Estonia) – 56 years of continuous zooplankton monitoring and research : [poster]
(Estonian University of Life Sciences, 2023) Blank, Kätlin; Haberman, Juta; Agasild, Helen; Tuvikene, Lea; Zingel, Priit; Nõges, Peeter; Bernotas, Priit; Cremona, Fabien
Presentation at the 11th International Shallow Lakes Conference, Estonia 11.-16.06.2023.
Opportunities for combining data of Estonian and Russian monitoring to reflect on water quality in large transboundary Lake Peipsi
(Elsevier, 2022) Tammeorg, Olga; Tuvikene, Lea; Kondratyev, Sergey; Golosov, Sergey; Zverev, Ilya; Zadonskaya, Olga; Nõges, Peeter
Lake Peipsi, one of the world’s largest lakes, is shared between Estonia and Russia. The water quality in different parts of the lake has so far been assessed independently. Here we explore opportunities for combining data of Estonian and Russian monitoring. For that, we 1) analysed the compatibility of data for some water quality variables; 2) estimated the potential effects of the differences in sampling frequency; 3) provided a few regression models to calculate the missing data for months not sampled by the Russian side. Data of the concurrent Estonian and Russian sampling indicated a good compatibility. Estonian data analysis suggested that water quality assessment results are sensitive to sampling frequency. For example, total phosphorus (TP) in the largest basin showed a long-term decreasing trend in three month data that disappeared when data for other months were added. Disregarding some months may lead to underor overestimation of certain factors with no consistency in the response of different basins. Hence, data of the whole ice-free period are recommended for an adequate water quality assessment. Furthermore, we demonstrated that monthly values of the water quality variables of the same year are autocorrelated. Based on this, we filled the gaps in the long-term data and compiled a dataset for the whole lake that enables its most comprehensive use in water quality assessment and management. Long-term data revealed no water quality improvement of Lake Peipsi. Further reduction of the external nutrient load is needed. Eutrophication is sustained by high internal phosphorus load.
Sediment phosphorus mobility in Võrtsjärv, a large shallow lake: Insights from phosphorus sorption experiments and long-term monitoring
(Elsevier, 2022) Tammeorg, Olga; Nürnberg, Gertrud K.; Tõnno, Ilmar; Kisand, Anu; Tuvikene, Lea; Nõges, Tiina; Nõges, Peeter
Sediment phosphorus (P) recycling is one of the key issues in lake water quality management. We studied sediment P mobility in Võrtsjärv, a large shallow lake in Estonia using both sorption experiments and long-term (1985–2020) monitoring data of the lake. Over the years studied, the lake has undergone a decline in external phosphorus loading (EL), while no improvement in phytoplankton indicators was observed. The results of the sorption experiments revealed that it may be successfully used as a tool to determine P forms involved in P retention, as up to 100%of the P fromthe water column was detected in sediments. Incubation of wet sediment is preferred to dry because of the sensitivity of organic P to desiccation. In the sediments of Võrtsjärv, the labile P (Lab-P) and iron bound (Fe-P) fractions are the major forms of the mobile pool that supply internal P load as sediment released P. The internal P load calculated from summer total P (TP) increases (ILin situ) in the water column was on average 42%, but could reach 240% of EL at extreme environmental conditions. ILin situ was correlated with the active area, which resembles the area involved in redox-related P release in polymictic lakes, and with the mean bottom shear stress in summer. ILin situ showed a similar decreasing pattern as the external P load over the years 1985–2020, and was likely driven by the decrease of the pool of releasable P. Similarly, the decreases in sediment loading by P retention in our P sorption experiment were associated with decreases in the concentration of the potentially mobile P forms (mainly Lab-P and Fe-P). These results show that changes in external P loading can successfully control internal P loading and are useful in water quality management of large lakes.
Siseveekogud : õpik kõrgkoolidele
(Kalanduse teabekeskus, 2020) Järvalt, Ain; Järvekülg, Rein; Kisand, Anu; Mäemets, Helle; Ott, Ingmar; Panksep, Kristel; Pedusaar, Tiia; Tammert, Helen; Timm, Henn; Tuvikene, Arvo; Tuvikene, Lea; Tõnno, Ilmar; Vilbaste, Sirje; Ott, Ingmar (koostaja); Timm, Henn (koostaja)
Inimeste kõige tavalisemad seosed siseveekogudega on matkamine, kalapüük, suplemine, janu kustutamine ja taimede kastmine. Et veekogude ääres viibimine mõjub paljudele rahustavalt, on jõgedel-järvedel miljonivaadete kaudu kindel koht ka kinnisvaraäris. Veekogudeta ei saa läbi sportlased (purjetajad, sõudjad ja motohuvilised). Leidub selliseidki indiviide, keda meelitavad mittesöödavad või koguni palja silmaga nähtamatud vee-elanikud. Eesti on väike madal maa, millel on pikk mererand, aga kus leidub ka palju siseveekogusid. Eriline on kahe suure järve – Peipsi ja Võrtsjärve – asumine lähestikku. Seisuvete pindala osakaalu järgi kogu riigi pindalast on Eesti Euroopas pärast Soomet ja Rootsit koos Norraga kolmandal-neljandal kohal. Eesti ja tema ümbrus on puhta veega seni niisiis hästi varustatud, kuid see rikkus ühtlasi kohustab veekogusid heaperemehelikult ja jätkusuutlikult majandama. Ka Eestis on muresid nii veevarude, veekogude kui nende seisundiga. Sisevete uurimine on Eestis kestnud juba üle 100 aasta. Seda on süstemaatiliselt korraldanud nii Looduseuurijate Selts, Tartu Riiklik Ülikool, Teaduste Akadeemia kui Maaülikool. Suurte järvede kõrval pole unustatud väikesi järvi ega vooluveekogusid. Uurida vee ja veekogude omadusi, arendada ja kasvatada nende spetsialiste ongi mõistlik seal, kus on, mida tundma õppida. Üha enam leitakse seoseid looduslike ja inimtekkeliste mõjurite ning ökosüsteemide vastuste vahel. Ühtlasi ühendatakse neid seoseid sotsiaalmajanduslike küsimuste ja looduskaitsega. Eesti siseveekogude kohta on peale arvukate ja enamasti võõrkeelsete teadusartiklite ilmunud ka eestikeelseid raamatuid. Siin neist väike loetelu: väikejärved (Eesti järved, 1968; Mäemets, 1977; Laarmaa jt 2019); Võrtsjärv (1973, 2003); Peipsi (1999, 2008), vooluveed (Järvekülg jt 2001; Timm jt 2019). Kalaraamatuid esindavad Mikelsaar (1984) ning Hunt (2019), veetaimi „Eesti taimede määraja“ (2010). Silmaga nähtavate veeselgrootute ülevaate pakub Timm (2015). Ülevaatlikku eestikeelset õpikut siseveekogude ning nende talitlemise kohta seni polnud. Eesti ülikoolides on kõigil kolmel õppetasandil (bakalaureuse-, magistri- ja doktoriõpe) õppekavasid, kus vajatakse teadmisi siseveekogudest. Võõrkeelseid eeskujusid leidub päris mitu, kuid need käsitlevad enamasti kas ainult hüdrobioloogiat või limnoloogiat. Esimene on elustiku-, teine keskkonna-alase suunitlusega. Uus õpik sisaldab mõlemaid ning sobib loodetavasti paljudele loodusteaduslikele ja looduskaitselistele kursustele, eriti bakalaureusetasemel. Õpik koosneb kolmest suurest alajaotusest: (1) siseveekogude füüsikalis-keemiline iseloomustus, levik ja teke; (2) elupaigad veekogudes, olulised elustikurühmad ning nendevahelised suhted; (3) siseveekogude majandamine, kaitse ja tervendamine. Peamiselt vaadeldakse Eesti siseveekogusid, aga seda kogu maailma taustal. Koostajad loodavad, et raamat annab lugejatele nii vastuseid küsimustele kui ka süvendab huvi sisevete kui kaunite, põnevate ning inimestele eluliselt oluliste loodusobjektide suhtes.
Stratification strength and light climate explain variation in chlorophyll a at the continental scale in a European multilake survey in a heatwave summer
(ASLO, 2021) Donis, Daphne; Mantzouki, Evanthia; McGinnis, Daniel F.; Vachon, Dominic; Gallego, Irene; Grossart, Hans‐Peter; Senerpont Domis, Lisette N.; Teurlincx, Sven; Seelen, Laura; Lürling, Miquel; Verstijnen, Yvon; Maliaka, Valentini; Fonvielle, Jeremy; Visser, Petra M.; Verspagen, Jolanda; Herk, Maria; Antoniou, Maria G.; Tsiarta, Nikoletta; McCarthy, Valerie; Perello, Victor C.; Machado‐Vieira, Danielle; Oliveira, Alinne Gurjão; Maronić, Dubravka Špoljarić; Stević, Filip; Pfeiffer, Tanja Žuna; Vucelić, Itana Bokan; Žutinić, Petar; Udovič, Marija Gligora; Plenković‐Moraj, Anđelka; Bláha, Luděk; Geriš, Rodan; Fránková, Markéta; Christoffersen, Kirsten Seestern; Warming Trine Perlt; Feldmann, Tõnu; Laas, Alo; Panksep, Kristel; Tuvikene, Lea; Kangro, Kersti; Koreivienė, Judita; Karosienė, Jūratė; Kasperovičienė, Jūratė; Savadova‐Ratkus, Ksenija; Vitonytė, Irma; Häggqvist, Kerstin; Salmi, Pauliina; Arvola, Lauri; Rothhaupt, Karl; Avagianos, Christos; Kaloudis, Triantafyllos; Gkelis, Spyros; Panou, Manthos; Triantis, Theodoros; Zervou, Sevasti‐Kiriaki; Hiskia, Anastasia; Obertegger, Ulrike; Boscaini, Adriano; Flaim, Giovanna; Salmaso, Nico; Cerasino, Leonardo; Haande, Sigrid; Skjelbred, Birger; Grabowska, Magdalena; Karpowicz, Maciej; Chmura, Damian; Nawrocka, Lidia; Kobos, Justyna; Mazur‐Marzec, Hanna; Alcaraz‐Párraga, Pablo; Wilk‐Woźniak, Elżbieta; Krztoń, Wojciech; Walusiak, Edward; Gagala‐Borowska, Ilona; Mankiewicz‐Boczek, Joana; Toporowska, Magdalena; Pawlik‐Skowronska, Barbara; Niedźwiecki, Michał; Pęczuła, Wojciech; Napiórkowska‐Krzebietke, Agnieszka; Dunalska, Julita; Sieńska, Justyna; Szymański, Daniel; Kruk, Marek; Budzyńska, Agnieszka; Goldyn, Ryszard; Kozak, Anna; Rosińska, Joanna; Szeląg‐Wasielewska, Elżbieta; Domek, Piotr; Jakubowska‐Krepska, Natalia; Kwasizur, Kinga; Messyasz, Beata; Pełechata, Aleksandra; Pełechaty, Mariusz; Kokocinski, Mikolaj; Madrecka‐Witkowska, Beata; Kostrzewska‐Szlakowska, Iwona; Frąk, Magdalena; Bańkowska‐Sobczak, Agnieszka; Wasilewicz, Michał; Ochocka, Agnieszka; Pasztaleniec, Agnieszka; Jasser, Iwona; Antão‐Geraldes, Ana M.; Leira, Manel; Vasconcelos, Vitor; Morais, Joao; Vale, Micaela; Raposeiro, Pedro M.; Gonçalves, Vítor; Aleksovski, Boris; Krstić, Svetislav; Nemova, Hana; Drastichova, Iveta; Chomova, Lucia; Remec‐Rekar, Spela; Elersek, Tina; Hansson, Lars‐Anders; Urrutia‐Cordero, Pablo; Bravo, Andrea G.; Buck, Moritz; Colom‐Montero, William; Mustonen, Kristiina; Pierson, Don; Yang, Yang; Richardson, Jessica; Edwards, Christine; Cromie, Hannah; Delgado‐Martín, Jordi; García, David; Cereijo, Jose Luís; Gomà, Joan; Trapote, Mari Carmen; Vegas‐Vilarrúbia, Teresa; Obrador, Biel; García‐Murcia, Ana; Real, Monserrat; Romans, Elvira; Noguero‐Ribes, Jordi; Duque, David Parreño; Fernández‐Morán, Elísabeth; Úbeda, Bárbara; Gálvez, José Ángel; Catalán, Núria; Pérez‐Martínez, Carmen; Ramos‐Rodríguez, Eloísa; Cillero‐Castro, Carmen; Moreno‐Ostos, Enrique; Blanco, José María; Rodríguez, Valeriano; Montes‐Pérez, Jorge Juan; Palomino, Roberto L.; Rodríguez‐Pérez, Estela; Hernández, Armand; Carballeira, Rafael; Camacho, Antonio; Picazo, Antonio; Rochera, Carlos; Santamans, Anna C.; Ferriol, Carmen; Romo, Susana; Soria, Juan Miguel; Özen, Arda; Karan, Tünay; Demir, Nilsun; Beklioğlu, Meryem; Filiz, Nur; Levi, Eti; Iskin, Uğur; Bezirci, Gizem; Tavşanoğlu, Ülkü Nihan; Çelik, Kemal; Ozhan, Koray; Karakaya, Nusret; Koçer, Mehmet Ali Turan; Yilmaz, Mete; Maraşlıoğlu, Faruk; Fakioglu, Özden; Soylu, Elif Neyran; Yağcı, Meral Apaydın; Çınar, Şakir; Çapkın, Kadir; Yağcı, Abdulkadir; Cesur, Mehmet; Bilgin, Fuat; Bulut, Cafer; Uysal, Rahmi; Latife, Köker; Akçaalan, Reyhan; Albay, Meriç; Alp, Mehmet Tahir; Özkan, Korhan; Sevindik, Tuğba Ongun; Tunca, Hatice; Önem, Burçin; Paerl, Hans; Carey, Cayelan C.; Ibelings, Bastiaan W.
To determine the drivers of phytoplankton biomass, we collected standardized morphometric, physical, and biological data in 230 lakes across the Mediterranean, Continental, and Boreal climatic zones of the European continent. Multilinear regression models tested on this snapshot of mostly eutrophic lakes (median total phos- phorus [TP] = 0.06 and total nitrogen [TN] = 0.7 mg L 1 ), and its subsets (2 depth types and 3 climatic zones), show that light climate and stratification strength were the most significant explanatory variables for chloro- phyll a (Chl a) variance. TN was a significant predictor for phytoplankton biomass for shallow and continental lakes, while TP never appeared as an explanatory variable, suggesting that under high TP, light, which partially controls stratification strength, becomes limiting for phytoplankton development. Mediterranean lakes were the warmest yet most weakly stratified and had significantly less Chl a than Boreal lakes, where the temperature anomaly from the long-term average, during a summer heatwave was the highest (+4 C) and showed a signifi- cant, exponential relationship with stratification strength. This European survey represents a summer snapshot of phytoplankton biomass and its drivers, and lends support that light and stratification metrics, which are both affected by climate change, are better predictors for phytoplankton biomass in nutrient-rich lakes than nutrient concentrations and surface temperature.
Synergy between Satellite Altimetry and Optical Water Quality Data towards Improved Estimation of Lakes Ecological Status
(MDPI, 2021) Ansper-Toomsalu, Ave; Alikas, Krista; Nielsen, Karina; Tuvikene, Lea; Kangro, Kersti; Chair of Hydrobiology and Fishery
European countries are obligated to monitor and estimate ecological status of lakes under European Union Water Framework Directive (2000/60/EC) for sustainable lakes’ ecosystems in the future. In large and shallow lakes, physical, chemical, and biological water quality parameters are influenced by the high natural variability of water level, exceeding anthropogenic variability, and causing large uncertainty to the assessment of ecological status. Correction of metric values used for the assessment of ecological status for the effect of natural water level fluctuation reduces the signal-to-noise ratio in data and decreases the uncertainty of the status estimate. Here we have explored the potential to create synergy between optical and altimetry data for more accurate estimation of ecological status class of lakes. We have combined data from Sentinel-3 Synthetic Aperture Radar Altimeter and Cryosat-2 SAR Interferometric Radar Altimeter to derive water level estimations in order to apply corrections for chlorophyll a, phytoplankton biomass, and Secchi disc depth estimations from Sentinel-3 Ocean and Land Color Instrument data. Long-term in situ data was used to develop the methodology for the correction of water quality data for the effects of water level applicable on the satellite data. The study shows suitability and potential to combine optical and altimetry data to support in situ measurements and thereby support lake monitoring and management. Combination of two different types of satellite data from the continuous Copernicus program will advance the monitoring of lakes and improves the estimation of ecological status under European Union Water Framework Directive.
Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins
(MDPI, 2018) Mantzouki, Evanthia; Lürling, Miquel; Fastner, Jutta; De Senerpont Domis, Lisette; Wilk-Woźniak, Elżbieta; Koreivienė, Judita; Seelen, Laura; Teurlincx, Sven; Verstijnen, Yvon; Krztoń, Wojciech; Walusiak, Edward; Karosienė, Jūratė; Kasperovičienė, Jūratė; Savadova, Ksenija; Vitonytė, Irma; Cillero-Castro, Carmen; Budzynska, Agnieszka; Goldyn, Ryszard; Kozak, Anna; Rosińska, Joanna; Szeląg-Wasielewska, Elżbieta; Domek, Piotr; Jakubowska-Krepska, Natalia; Kwasizur, Kinga; Messyasz, Beata; Pełechata, Aleksandra; Pełechaty, Mariusz; Kokocinski, Mikolaj; García-Murcia, Ana; Real, Monserrat; Romans, Elvira; Noguero-Ribes, Jordi; Duque, David Parreño; Fernández-Morán, Elísabeth; Karakaya, Nusret; Häggqvist, Kerstin; Demir, Nilsun; Beklioğlu, Meryem; Filiz, Nur; Levi, Eti E.; Iskin, Uğur; Bezirci, Gizem; Tavşanoğlu, Ülkü Nihan; Özhan, Koray; Gkelis, Spyros; Panou, Manthos; Fakioglu, Özden; Avagianos, Christos; Kaloudis, Triantafyllos; Çelik, Kemal; Yilmaz, Mete; Marcé, Rafael; Catalán, Nuria; Bravo, Andrea G.; Buck, Moritz; Colom-Montero, William; Mustonen, Kristiina; Pierson, Don; Yang, Yang; Raposeiro, Pedro M.; Gonçalves, Vítor; Antoniou, Maria G.; Tsiarta, Nikoletta; McCarthy, Valerie; Perello, Victor C.; Feldmann, Tõnu; Laas, Alo; Panksep, Kristel; Tuvikene, Lea; Gagala, Ilona; Mankiewicz-Boczek, Joana; Yağcı, Meral Apaydın; Çınar, Şakir; Çapkın, Kadir; Yağcı, Abdulkadir; Cesur, Mehmet; Bilgin, Fuat; Bulut, Cafer; Uysal, Rahmi; Obertegger, Ulrike; Boscaini, Adriano; Flaim, Giovanna; Salmaso, Nico; Cerasino, Leonardo; Richardson, Jessica; Visser, Petra M.; Verspagen, Jolanda M. H.; Karan, Tünay; Soylu, Elif Neyran; Maraşlıoğlu, Faruk; Napiórkowska-Krzebietke, Agnieszka; Ochocka, Agnieszka; Pasztaleniec, Agnieszka; Antão-Geraldes, Ana M.; Vasconcelos, Vitor; Morais, João; Vale, Micaela; Köker, Latife; Akçaalan, Reyhan; Albay, Meriç; Maronić, Dubravka Špoljarić; Stević, Filip; Pfeiffer, Tanja Žuna; Fonvielle, Jeremy; Straile, Dietmar; Rothhaupt, Karl-Otto; Hansson, Lars-Anders; Urrutia-Cordero, Pablo; Bláha, Luděk; Geriš, Rodan; Fránková, Markéta; Kocer, Mehmet Ali Turan; Alp, Mehmet Tahir; Remec-Rekar, Spela; Elersek, Tina; Triantis, Theodoros; Zervou, Sevasti-Kiriaki; Hiskia, Anastasia; Haande, Sigrid; Skjelbred, Birger; Madrecka, Beata; Nemova, Hana; Drastichova, Iveta; Chomova, Lucia; Edwards, Christine; Sevindik, Tuğba Ongun; Tunca, Hatice; Önem, Burçin; Aleksovski, Boris; Krstić, Svetislav; Vucelić, Itana Bokan; Nawrocka, Lidia; Salmi, Pauliina; Machado-Vieira, Danielle; De Oliveira, Alinne Gurjão; Delgado-Martín, Jordi; García, David; Cereijo, Jose Luis; Gomà, Joan; Trapote, Mari Carmen; Vegas-Vilarrúbia, Teresa; Obrador, Biel; Grabowska, Magdalena; Karpowicz, Maciej; Chmura, Damian; Úbeda, Bárbara; Gálvez, José Ángel; Özen, Arda; Christoffersen, Kirsten S.; Warming Trine Perlt; Kobos, Justyna; Mazur-Marzec, Hanna; Pérez-Martínez, Carmen; Ramos-Rodríguez, Eloísa; Arvola, Lauri; Alcaraz-Párraga, Pablo; Toporowska, Magdalena; Pawlik-Skowronska, Barbara; Niedźwiecki, Michał; Pęczuła, Wojciech; Leira, Manel; Hernández, Armand; Moreno-Ostos, Enrique; Blanco, José María; Rodríguez, Valeriano; Montes-Pérez, Jorge Juan; Palomino, Roberto L.; Rodríguez-Pérez, Estela; Carballeira, Rafael; Camacho, Antonio; Picazo, Antonio; Rochera, Carlos; Santamans, Anna C.; Ferriol, Carmen; Romo, Susana; Soria, Juan Miguel; Dunalska, Julita; Sieńska, Justyna; Szymański, Daniel; Kruk, Marek; Kostrzewska-Szlakowska, Iwona; Jasser, Iwona; Žutinić, Petar; Udovič, Marija Gligora; Plenković-Moraj, Anđelka; Frąk, Magdalena; Bańkowska-Sobczak, Agnieszka; Wasilewicz, Michał; Özkan, Korhan; Maliaka, Valentini; Kangro, Kersti; Grossart, Hans-Peter; Paerl, Hans W.; Carey, Cayelan C.; Ibelings, Bas W.; Institute of Agricultural and Environmental Sciences
Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.
Towards Research Excellence and Innovation Capacity in Studing Lake Ecosystems Functional Structures and Climate Change Impact – TREICLAKE : [presentation]
(Eesti Maaülikool, 2023) Tuvikene, Lea
Esitlus "Euroopa Horisondi“ uute taotlusvoorude infopäeval Eesti Maaülikoolis, 11.01.2023
Võrtsjärv on võrratu! : [esitlus]
(Eesti Maaülikool, 2022) Tuvikene, Lea
Neljas üle-Eestiline avatud kalasadamate päev Limnoloogias, 2022.

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