TREICLAKE

Selle valdkonna püsiv URIhttp://hdl.handle.net/10492/7299

"Towards Research Excellence and Innovation Capacity in Studing Lake Ecosystems Functional Structures and Climate Change Impact " (1.01.2021−31.12.2023); Principal investigator: Lea Tuvikene, Estonian University of Life Sciences, Institute of Agricultural and Environmental Sciences, Chair of Hydrobiology and Fishery. Funder: European Commission

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Nüüd näidatakse 1 - 20 82

Comparison of larval perch feeding between littoral and open-water sites of the lakes : [presentation]
(Estonian University of Life Sciences, 2021) Karus, Katrit; Žagars, Matiss; Zingel, Priit; Agasild, Helen; Feldmann, Tõnu; Tuvikene, Arvo; Medne-Peipere, Madara; Puncule, Linda
The presentation took place at the 10th International Conference on Shallow Lakes in 2021.
Nitrogen in Estonian lakes – the trends and impacts on Cyanobacteria : [presentation]
(Estonian University of Life Sciences, 2021) Nõges, Tiina; Maileht, Kairi
• The relative role of N&P to control eutrophication in lakes is continuously debated (Schindler et al. 2008). • Estonian limnologists have been P-believers as the post-socialist sharp reduction of N loading brought back cyanobacterial blooms in Lake Peipsi (Nõges et al. 2005) • The long debate has not discredited the importance of P-Control, but displayed evidence on the significance of N reduction to recover lake ecosystems (Paerl et al. 2016) • Chemically reduced N forms, such as NH4 + and urea favour non-N-fixing cyanobacteria (McCarthy et al. 2009)
Catchment soil characteristics predict organic carbon, nitrogen, and phosphorus levels in temperate lakes
(The University of Chicago Press, 2021) Sepp, Margot; Kõiv, Toomas; Nõges, Peeter; Nõges, Tiina; Newell, Silvia E.; McCarthy, Mark J.; Institute of Agricultural and Environmental Sciences. Estonian University of Life Sciences
Allochthonous supply of dissolved organic matter (DOM) and nutrients from the catchment have a sub- stantial impact on the physical and chemical properties of lake water. Transport of DOM and nutrients is affected by different catchment characteristics, e.g., catchment area, soil and land cover, and population density. The aim of this study was to relate geological, hydrological, land-cover, and soil characteristics of 52 temperate catchments in Estonia to variability in DOM (measured as dissolved organic carbon [DOC]), total organic nitrogen (TON), and total phosphorus (TP) in lakes and to assess the relative importance of different land-cover and soil types as sources of these substances. DOC, TON, and TP were very diverse in the studied lakes. Strong positive correlation between DOC and TON indicated that these substances had similar concentration patterns and sources. Catchment soil cover was the best predictor of DOC, TON, and TP levels in lakes, explaining up to 43.8% of their variabilities. This obser- vation can partly be explained by different soil organic carbon (SOC) content: soils with higher SOC were associated with higher lake DOC and TON, whereas soils with low SOC corresponded to lower DOC and TON. Similar to other temperate lakes, bogs and peat soils were a major source of DOM in our studied lakes. DOC, TON, and color were positively associated with percentages of peat soils in the catchment. On the other hand, TP increased with the pro- portion of urban areas in the catchments, indicating the importance of human impact on its concentration. Under- standing the impact of different catchment characteristics on DOC, TON, and TP in temperate lakes is crucial for developing transport models used for predicting future levels of DOM and nutrients under changing climate and land use.
6 põhjust, miks Peipsi järv vajab tähelepanu : [faktileht]
(Eesti Maaülikool, 2021) Eesti Maaülikool
Peipsi järv on Euroopa üks kalarikkam ja suurim piiriülene järv. Õigupoolest koosneb järv kolmest osast: Peipsi, Pihkva ja Lämmijärvest. Kuna jagame järve Venemaaga, siis keskkonnakaitse meetmeid tuleb ellu viia üheskoos. Peipsi-Pihkva järv on oma suuruse (3555 km2) kohta madal järv: tema keskmine sügavus on ainult 7,1 meetrit. Suurte ja madalate järvede ökoloogiline seisund ehk tervis oleneb väga palju keskkonnatngimustest. Järve tervist mõjutavad üheaegselt nii looduslikud kui inimtekkelised tegurid, seejuures on neil sageli raske vahet teha.
Impact of climate change and other ecological factors on selected fish populations and fishery in Estonian large lakes
(Estonian University of Life Sciences, 2021) Öğlü, Burak; Kaart, Tanel; Kangur, Külli; Cremona, Fabien; Institute of Agricultural and Environmental Sciences; Kuparinen, Anna (opponent); Olli, Kalle (pre-opponent)
Human activities and climate change have become the most consequential threats to freshwater ecosystems and their inhabitants, especially fish. The response of the fish population to their environment is not always straightforward because of joint effect of multiple parameters. Fish and fisheries in shallow lakes can be directly affected by changes in air temperature, and also changes can occur via other factors in lakes that are under the influence of climate change. Also, response of each fish species to those parameters can vary depending on their tolerance and adaptation. Therefore, examining complex relationships between fish and their environment plays important role at understanding the dynamic of fish population and fisheries. In this study, we aimed to determine general driving factors, including climate change impact, for fish and fishery in Estonian large lakes. Results show that although winter is one of the most affected seasons by climate change in this region, then the selected fish species and eel fishery in Estonian large lakes were more sensitive to other environmental parameters. However, since the changes in winter surface water temperature and ice formation can affect other parameters, the indirect effect should not be ignored. Nutrients, spring-summer temperature and alkalinity were the most important environmental parameters for the selected fish biomass. We found that the high blue-green algae biomass during restocking period is the strongest negative impact for the eel fishery in Lake Võrtsjärv. The impact of factors can occur subsequently in fish communities and may lead to irreversible consequences, whereas the effects of concurrent climate change and nutrient enrichment can mutually reinforce their symptoms.
Three years into studying N cycling in lakes Peipsi and Võrtsjärv - where we stand, and what’s next : [presentation]
(Estonian University of Life Sciences, 2021) McCarthy, Mark J.
Objectives: 1. Characterize and quantify water column nitrogen (N) cycling rates in lakes Peipsi and Võrtsjärv a. Ammonium (NH 4 ++) uptake and regeneration b. Nitrification 2. Characterize and quantify sediment water interface N transformations and O 2 demand in Lake Võrtsjärv a. Net nutrient (NO x , NH 4 ++, urea, ortho P), O 2 , and N 2 fluxes b. Potential denitrification and DNRA c. Possible anammox d. N 2 fixation (heterotrophic)
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.
The immediate response of freshwater phytoplankton to increased nitrogen loading differ among climate warming scenarios - a mesocosms experiments : [presenation]
(2021) Tamm, Marju; Boedecker, Ashlynn; Freiberg, René; Jeppesen, Erik
The presentation took place at the 10th International Conference on Shallow Lakes in 2021.
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.
Diet and trophic niche of the invasive signal crayfish in the first invaded Italian stream ecosystem
(Nature, 2021) Ercoli, Fabio; Ghia, Daniela; Gruppuso, Laura; Fea, Gianluca; Bo, Tiziano; Ruokonen, Timo J.
The occurrence of the signal crayfsh Pacifastacus leniusculus in the Valla Stream was the frst established population of this invasive species recorded in an Italian stream ecosystem. We evaluated the seasonality of diet and trophic niche of invasive signal crayfsh in order to estimate the ecological role and efects on native communities of the stream ecosystem. We studied the diferences in food source use between sexes, life stages and seasons using carbon and nitrogen stable isotope analyses. To supplement stable isotope analyses, we evaluated food source usage using traditional stomach content analysis. We tested the hypothesis that juveniles have a diferent diet, showing diferent trophic niches, compared to adults. Results indicated that signal crayfsh adult and juvenile diets mainly rely on macroinvertebrates and periphyton in summer, shifting to mostly periphyton in autumn. Although the two age classes occupied an equivalent trophic niche, juveniles showed slightly diferent carbon isotope values, suggesting a somewhat ontogenetic shift consistent among seasons. No signifcant diferences were found in adult and juvenile diets between summer and autumn seasons. Our fndings suggest that signal crayfsh juveniles and adults exhibited seasonal feeding habits, probably due to ecological behaviour rather than food resource availability, and that both are likely to impose similar efects on macroinvertebrate communities in this and similar stream ecosystems
Lake food webs and C metabolism across gradients of catchment alkalinity and climate : [presentation]
(Estonian University of Life Sciences, 2021) Nõges, Tiina; Agasild, Helen; Cremona, Fabien; Laas, Alo; Nõges, Peeter; Tõnno, Ilmar; Zingel, Priit
The presentation took place at the 10th International Conference on Shallow Lakes in 2021.
Lake food webs and carbon metabolism : [presentation]
(Estonian University of Life Sciences, 2021) Nõges, Tiina
The presentation took place at the 18th World Lake Conference.
Larval and juvenile perch feeding in some Estonian and Latvian study lakes : [poster]
(Estonian University of Life Sciences, 2021) Karus, Katrit; Agasild, Helen; Feldmann, Tõnu; Tuvikene, Arvo; Medne-Peipere, Madara; Žagars, Matiss; Puncule, Linda; Zingel, Priit
The presentation took place at the Lahti Lakes 2021 Symposium.
Catchment land cover and soil as predictors of organic carbon, nitrogen, and phosphorus levels in temperate lakes : [presentation]
(Estonian University of Life Sciences, 2021) Sepp, Margot; Kõiv, Toomas; Nõges, Peeter; Nõges, Tiina; Newell, Silvia; McCarthy, Mark J.
The presentation took place at the 10th International Conference on Shallow Lakes in 2021.
Supplementary materials to the article "Catchment soil characteristics predict organic carbon, nitrogen, and phosphorus levels in temperate lakes"
(Estonian University of Life Sciences, 2021) Sepp, Margot; Kõiv, Toomas; Nõges, Peeter; Nõges, Tiina; Newell, Silvia E.; McCarthy, Mark J.
The supplementary material contains 6 tables.
Hydrometeorological and climatic control over lake phytoplankton : the importance of time scales
(Estonian University of Life Sciences, 2021) Janatian, Nasime; Nõges, Peeter; Obrador, Biel; Cremona, Fabien; Laas, Alo; Institute of Agricultural and Environmental Sciences; Uusi-Heikkilä, Silvia (opponent)
Phytoplankton reflects changes in the environment and plays a vital role in biogeochemical cycles and the climate system. The thesis attempts to link the phytoplankton dynamics with the timing, intensity, and duration of the local forcing factors at different time scales. We highlight the influence of two extremes of the wind gradient – storms and atmospheric stilling, on lake environments and phytoplankton dynamics over short and long periods, several aspects of which are poorly understood. Until recently, atmospheric stilling as a climatic phenomenon has been largely overlooked in lakes studies. To fill this research gap, we focussed on a large shallow polymictic lake (Võrtsjärv, Estonia), that was affected by a 30% decrease in average wind speed since 1996, and for which a long-term (54 years) phytoplankton and hydrometeorological database was available. Further, a contradiction between the continuous decrease in the lake’s nutrient loading and an increasing trend in phytoplankton biomass emerged as a topic of interest for this thesis. We summarise how storms interact with and alter the dynamic of phytoplankton communities. Further, we highlight to what extent this impact can change the ecological processes (e.g., nutrient, carbon, and energy cycling) within lakes and their environmental conditions in the short and long term. Using Nonmetric Multidimensional Scaling ordination of phytoplankton community composition for the years 1964–2017, we revealed three distinct periods with breaking points coinciding with abrupt changes in the wind and/or water level. We introduced a concept of "light niche," a newly discovered mechanism of meteorological control over phytoplankton in light-limited shallow lakes. Combining the monthly phytoplankton data with daily data on hydrometeorological forcing factors — thermal, light, wind, and water-level regimes and using variance partitioning with linear mixed effect modelling (LME), we found that (i) the external forcing factors relevant for each phytoplankton variable could be individualised by having a similar variance partitioning among time scales as the particular phytoplankton variable; (ii) with the largest seasonal variation component, the dominant shade-tolerant filamentous cyanobacteria were most affected by seasonal factors such as solar irradiance and water level; (iii) the LME was proven appropriate for resolving the temporal cross-scale issues.
Black and white, day and night – fish diurnal movements in two different Amazonian lakes : [presentation]
(2021) Zingel, Priit; Tuvikene, Arvo; Feldmann, Tõnu; Agasild, Helen
The presentation took place at the 10th International Conference on Shallow Lakes in 2021.
Supplementary data to the article "Nitrate as a predictor of cyanobacteria biomass in eutrophic lakes in a climate change context"
(Estonian University of Life Sciences, 2022) Cremona, Fabien; Öğlü, Burak; McCarthy, Mark J.; Newell, Silvia E.; Nõges, Peeter; Nõges, Tiina
Supplementary material: empirical model terms for the biomass of cyanobacteria (VO_Bcyan) and nitrate concentration (VO_NO3) in Lake Võrtsjärv, using measured nitrate concentration of tributaries Väike Emajõgi (oVema_), Tänassilma (oTana_), Õhne (oOhne_) and Tarvastu (oTarv_).
What is the use of lake science in the management and maintenance of lakes? : [presentation]
(Estonian University of Life Sciences, 2022) Tuvikene, Lea
EU Horizon 2020 Project „Towards Research Excellence and Innovation Capacity in Studying Lake Ecosystems’ Functional Structures and Climate Change Impact“ – TREICLAKE – aims to increase the scientific expertise of Estonian lake researchers to achieve larger impact not only in science but also in society at large.
Effects of environmentally relevant concentrations of microplastics on amphipods
(Elsevier, 2022) Rani-Borges, Barbara; Meitern, Richard; Teesalu, Paul; Raudna-Kristoffersen, Merilin; Kreitsberg, Randel; Heinlaan, Margit; Tuvikene, Arvo; Ivask, Angela
Lack of microplastics (MP) toxicity studies involving environmentally relevant concentrations and exposure times is concerning. Here we analyzed the potential adverse effects of low density polyethylene (LDPE) MP at environmentally relevant concentration in sub-chronic exposure to two amphipods Gmelinoides fasciatus and Gammarus lacustris, species that naturally compete with each other for their habitats. 14-day exposure to 2 μg/L (8 particles/L corresponding to low exposure) and 2 mg/L (~8400 particles/L, corresponding to high exposure) of 53–100 μm LDPE MP were used to assess ingestion and egestion of MP, evaluate its effects on amphipod mortality, swimming ability and oxidative stress level. Both amphipod species were effectively ingesting and egesting LDPE MP. On the average, 0.8 and 2.5 MP particles were identified in the intestines of each amphipod exposed to 2 μg/L and 2 mg/L LDPE MP, respectively. Therefore, intestinal MP after 14-day exposure did not fully reflect the differences in LDPE MP exposure concentrations. Increased mortality of both amphipods was observed at 2 mg/L LDPE MP and in case of G. lacustris also at 2 μg/L exposure. The effect of LDPE on swimming activity was observed only in case of G. fasciatus. Oxidative stress marker enzymes SOD, GPx and reduced glutathione GSH varied according to amphipod species and LDPE MP concentration. In general G. lacustris was more sensitive towards LDPE MP induced oxidative stress. Overall, the results suggested that in MP polluted environments, G. lacustris may lose its already naturally low competitiveness and become overcompeted by other more resistant species. The fact that in the sub-chronic foodborne exposure to environmentally relevant and higher LDPE MP concentrations all the observed toxicological endpoints were affected refers to the potential of MP to affect and disrupt aquatic communities in the longer perspective.

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