Browsing by Subject "strain on the water system"

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  • Bhattacharjee, Joy; Marttila, Hannu; Launiainen, Samuli; Lepistö, Ahti; Kløve, Bjørn (Elsevier, 2021)
    Science of The Total Environment 779 (2021), 146419
    Maintaining and improving surface water quality requires knowledge of nutrient and sediment loads due to past and future land-use practices, but historical data on land cover and its changes are often lacking. In this study, we tested whether land-use-specific export coefficients can be used together with satellite images (Landsat) and/or regional land-use statistics to estimate riverine nutrient loads and concentrations of total nitrogen (TN), total phosphorus (TP), and suspended solids (SS). The study area, Simojoki (3160 km2) in northern Finland, has been intensively drained for peatland forestry since the 1960s. We used different approaches at multiple sub-catchment scales to simulate TN, TP, and SS export in the Simojoki catchment. The uncertainty in estimates based on specific export coefficients was quantified based on historical land-use changes (derived from Landsat data), and an uncertainty boundary was established for each land-use. The uncertainty boundary captured at least 60% of measured values of TN, TP, and SS loads or concentrations. However, the uncertainty in estimates compared with measured values ranged from 7% to 20% for TN, 0% to 18% for TP, and 13% to 43% for SS for different catchments. Some discrepancy between predicted and measured loads and concentrations was expected, as the method did not account for inter-annual variability in hydrological conditions or river processes. However, combining historical land-use change estimates with simple export coefficients can be a practical approach for evaluating the influence on water quality of historical land-use changes such as peatland drainage for forest establishment.
  • Sörenson, Eva; Bertos-Fortis, Mireia; Farnelid, Hanna; Kremp, Anke; Krüger, Karen; Lindehoff, Elin; Legrand, Catherine (Wiley & Sons, 2019)
    Environmental Microbiology Reports, 11: 425-433
    Phytoplankton and bacteria interactions have a significant role in aquatic ecosystem functioning. Associations can range from mutualistic to parasitic, shaping biogeochemical cycles and having a direct influence on phytoplankton growth. How variations in phenotype and sampling location, affect the phytoplankton microbiome is largely unknown. A high-resolution characterization of the bacterial community in cultures of the dinoflagellate Alexandrium was performed on strains isolated from different geographical locations and at varying anthropogenic impact levels. Microbiomes of Baltic Sea Alexandrium ostenfeldii isolates were dominated by Betaproteobacteria and were consistent over phenotypic and genotypic Alexandrium strain variation, resulting in identification of an A. ostenfeldii core microbiome. Comparisons with in situ bacterial communities showed that taxa found in this A. ostenfeldii core were specifically associated to dinoflagellate dynamics in the Baltic Sea. Microbiomes of Alexandrium tamarense and minutum, isolated from the Mediterranean Sea, differed from those of A. ostenfeldii in bacterial diversity and composition but displayed high consistency, and a core set of bacterial taxa was identified. This indicates that Alexandrium isolates with diverse phenotypes host predictable, species-specific, core microbiomes reflecting the abiotic conditions from which they were isolated. These findings enable in-depth studies of potential interactions occurring between Alexandrium and specific bacterial taxa.
  • Nystén, Taina; Äystö, Lauri; Laitinen, Jyrki; Mehtonen, Jukka; Alhola, Katriina; Leppänen, Matti; Perkola, Noora; Vieno, Niina; Sikanen, Tiina; Yli-Kauhaluoma, Jari; Karlsson, Sanja; Virtanen, Virpi; Teräsalmi, Eeva (Finnish Environment Institute, 2019)
    SYKE Policy Brief 17.5.2019
  • Wang, Huan; García Molinos, Jorge; Heino, Jani; Zhang, Huan; Zhang, Peiyu; Xu, Jun (Pergamon, 2021)
    Environment International 153 (2021), 106494
    Eutrophication is a major problem currently impacting many surface water ecosystems. Impacts of increased nutrient concentrations on biodiversity may differ between different scales, different organism groups, and different trophic states. Surveys at different spatial scales have suggested that biodiversity of different taxa may exhibit significant cross-taxon congruence. In our study, we examined the diversity of zooplankton and zoobenthos across 261 lakes in the Lake Taihu watershed, an area that is undergoing a severe eutrophication process. We tested the cross-taxon congruence in species richness and Shannon-Wiener diversity between zooplankton and zoobenthos along a nutrient gradient across the lakes. Our findings were consistent with the intermediate disturbance hypothesis, considering nutrient input as the disturbance. Also, we found significant cross-taxon congruence between zooplankton and zoobenthos diversities. Our results confirmed that excess nutrient levels resulted in diversity loss and community simplification. Zoobenthos were more sensitive to nutrient increases compared with zooplankton, which decreased cross-taxon congruence because these organism groups did not respond similarly to the anthropogenic disturbance.
  • Knuuttila, Seppo (Finnish Environment Institute, 2015)
    Reports of the Finnish Environment Institute 38/2015
    The report describes the results of pilot project aimed at improving the quality of data on transboundary nutrient loads, in particular, in the rivers Daugava and Nemunas. Two sampling rounds (in May and November 2013) were organised and executed by the Finnish Environment Institute (SYKE) in close cooperation with representatives from the participating countries, one laboratory from Latvia, two from Lithuania, three from Belarus and one from Finland. The results from the total nitrogen analyses of the different laboratories were in general comparable, while the total phosphorus results varied between the laboratories. One explanation might be that the analytical methods applied were not fully comparable; for example, the filtration of the samples before analysis of total phosphorus may have affected the results. Highest concentrations were observed at the Belarusian border. Both absolutely and relatively high concentrations of dissolved phosphorus in the rivers give an indication of a clear anthropogenic influence. A key finding of the project was that a reasonably good consensus and comparability has been reached on the phosphorus and nitrogen loads originating in the upstream catchment area and flowing into Latvia and Lithuania – even if the results were produced through separate data sets and by partly different methods. This is a good starting point for the efforts to further estimate the retention in the lower reaches in the Latvian and Lithuanian territories of the two rivers and the percentage of the transboundary nutrient loads which finally enter into the Baltic Sea. An equally important result of the project is the ability to now present – in connection with the data on the total riverine loads measured at the mouth of the rivers Daugava and Nemunas – complete data sets on nutrient loads at the border between Latvia or Lithuania and Belarus. This data also sup-ports the assessment of transboundary nutrient loads originating in the territory of Belarus (and Russia) in the catchment area of these two rivers.
  • Nieminen, Mika; Sallantaus, Tapani (Suoseura, 2020)
    Suo 72(1) (2020)
  • Lepistö, Ahti; Huttula, Timo; Bärlund, Ilona; Granlund, Kirsti; Härmä, Pekka; Kallio, Kari; Kiirikki, Mikko; Kirkkala, Teija; Koponen, Sampsa; Koskiaho, Jari; Kotamäki, Niina; Lindfors, Antti; Malve, Olli; Pyhälahti, Timo; Tattari, Sirkka; Törmä, Markus (Finnish Environment Institute, 2008)
    Reports of the Finnish Environment Institute 15/2008
  • Ropponen, Janne; Arola, Hanna; Kiuru, Petri; Huttula, Timo (Suomen ympäristökeskus, 2013)
    Reports of the Finnish Environment Institute 36/2013
    The City of Lappeenranta is considering options for its wastewater discharge sites in the future. One possibility is to release the treated wastewater into River Vuoksi, flowing through the City of Imatra, approximately 35 kilometres northeast from Lappeenranta. This report contains results from nutrient and fecal bacteria water quality modelling along River Vuoksi. The model endeavours to answer how the possible changes in wastewater discharge amounts and locations affect the river water quality near the freshwater intake at Svetogorsk, Russia. The river model was built using a river modelling system SOBEK from Deltares Systems. Calibration was done using data from the year 2010 and actual scenario simulations used 2011 data. According to the simulations there are no major water quality deviations compared to the current situation in normal operating scenarios, but there is some risk of water quality deterioration in certain catastrophic scenarios. The location of the discharge site might have some effect on the water quality due to the time required for the effluent to fully mix with the river water. Additionally a 3D research model of the southern Lake Saimaa was built to study passive tracer transport from two different sites near the City of Lappeenranta. The open source modelling software COHERENS was used to simulate scenarios during the open water period in years 2010 and 2011.
  • Thorsøe, Martin Hvarregaard; Andersen, Mikael Skou; Brady, Mark V.; Graversgaard, Morten; Kilis, Emils; Pedersen, Anders Branth; Pitzén, Samuli; Valve, Helena (Royal Swedish Academy of Sciences, 2021)
    Following decades of international collaboration to restore the Baltic Sea, we provide an assessment of the domestic implementation of measures agreed to limit diffuse agricultural pollution and the patterns of policy instruments applied. Despite the Helsinki Convention being unusually specific in detailing what measures countries should introduce, we find many shortcomings. These are most pronounced in the larger countries (Poland, Germany and Russia), while smaller countries perform better, notably Sweden and Estonia. The patterns of policy instruments applied differ, influenced by domestic politics. The limited use of complementary policy instruments suggests that other priorities overrule full and effective implementation, with engagement mirroring the advantages that a restored Baltic Sea can bring to countries. Using the European Agricultural Fund for Rural Development to support farmers in managing nutrients, particularly advisory services and investments in modern manure management technologies, represents a significant opportunity for reducing agricultural pollution in most countries.
  • Raateoja, Mika; Setälä, Outi (Finnish Environment Institute, 2016)
    Reports of the Finnish Environment Institute 27/2016
    This assessment on the environmental state of the Gulf of Finland in 1996 – 2014 was produced by together over 100 scientists from Estonia, Finland, and Russia in the context of the Gulf of Finland Year 2014. The thematic year aimed at – and succeeded in – giving additional value for the protection and restoration of the Gulf of Finland environment by enhancing political presence and interaction between the private sector, decision-makers, and citizens. This assessment concentrates on the past development and the current state of the Gulf of Finland environment and pressures affecting it. The themes include climate in the Gulf of Finland area, Gulf of Finland physics, geology and geodiversity, eutrophication, hazardous substances, biodiversity, fishes and fisheries, nonindigenous species, marine litter, underwater soundscape, maritime traffic and its safety, and environmental valuation. Each chapter also delivers expert opinions and recommendations for the future.