Finnish Environmental Institute

Helsinki, Finland

Finnish Environmental Institute

Helsinki, Finland

Time filter

Source Type

Oinonen M.,University of Helsinki | Oinonen M.,University of Turku | Hilasvuori E.,University of Helsinki | Hilasvuori E.,Finnish Environmental Institute | And 4 more authors.
Radiocarbon | Year: 2013

The era of early urbanization in Finland coincides with large variations in the atmospheric radiocarbon concentration around the 13th-14th centuries AD. Therefore, the uncertainties of an individual 14C date are too large to support studies of this time period effectively. In this work, we have employ tree-ring wiggle-matching methodology and used Bayesian modeling of dates to account for stratigraphical a priori information within Aboa Vetus Museum, Turku, Finland. The wiggle-match method helps significantly to overcome the calibration-curve-induced challenges within 14C dating. The results of the dating model agree with the typological dates of the archaeological finds and illustrate a gradual evolution of urbanization in one of the oldest cities in Finland. © 2013 by the Arizona Board of Regents on behalf of the University of Arizona.


Jurvelius J.,Finnish Game And Fisheries Research Institute | Marjomaki T.J.,University of Jyväskylä | Peltonen H.,Finnish Environmental Institute | Degtev A.,Petrozavodsk State University | And 3 more authors.
Hydrobiologia | Year: 2016

To evaluate the consistency of mobile and vertical echosounding results from the 1980s to the 2000s, fish density (fish ha−1) and target strength (TS, dB) estimates of single (70 and 200 kHz) and split (38 and 120 kHz) beam echo sounders were compared under varying light conditions. Acoustic estimates were compared with trawling results. During daytime hauls, the catch per swept area (CSA) of vendace and smelt were high at 10–15 m depth and low at 15–30 m depth. Around sunset, vendace and to some degree also smelt were concentrated at some meters above the thermocline. Around midnight, the CSA showed that smelt occupied higher water layers than vendace. Under different light conditions, both single and split beam echo sounders were in good agreement regarding the general level of fish density. In dusk and darkness, density estimates from echosounding and trawling as well as the TS-distribution between the single and split beam sounders were more consistent than those in daylight. We conclude that in boreal lakes single and split beam echosoundings outline, in comparable light conditions, consistent time series from the 1980s up to the year 2010. Darkness gives the best condition for estimating fish density and acoustic fish size. © 2016 Springer International Publishing Switzerland


Vahatalo A.V.,University of Helsinki | Vahatalo A.V.,Novia University of Applied Sciences | Aarnos H.,University of Helsinki | Hoikkala L.,University of Helsinki | And 3 more authors.
Marine Ecology Progress Series | Year: 2011

We assessed the responses of a nitrogen (N)-limited < 10 μm plankton community from the Baltic Sea to the 12 d photochemical transformation of dissolved organic matter (DOM). The photochemical transformation of DOM increased the biomass and the production of heterotrophic bacteria, flagellates, and ciliates in the following 10 d bioassay. The succession of heterotrophic plankton indicated a 3-level trophic transfer of photoproduced bioavailable DOM through bacteria and flagellates to ciliates. The photochemical transformation of DOM also stimulated the biomass and the production of phytoplankton through the photoproduction of bioavailable N initially incorporated into bacterial biomass. The grazing of bacterioplankton supplied N to phytoplankton directly, presumably due to mixotrophy, and indirectly by releasing dissolved N. The carbon stable isotope signature of plankton biomass was similar to that of allochthonous carbon, indicating that the photochemical transformations concerned primarily terrestrial DOM and therefore represented a microbial link between terrestrial DOM and planktonic production. The bacterial production stimulated by the photochemically produced labile DOM was related to the number of photons absorbed during the photochemical transformation of DOM for the determination of apparent quantum yield. According to the apparent quantum yield, the calculated summertime photoproduction of labile substrates contributes 2 to 5% to total bacterial production in the northern Baltic Sea. According to this study, the photochemical transformation of terrestrial DOM influences not only the initial production of bacterioplankton but can also stimulate higher trophic levels and autotrophic plankton in coastal waters. © Inter-Research 2011.


Majaneva M.,University of Helsinki | Majaneva M.,Finnish Environmental Institute | Rintala J.-M.,University of Helsinki | Rintala J.-M.,Finnish Environmental Institute | And 3 more authors.
Polar Biology | Year: 2012

The Baltic Sea is one of the world's largest brackish water basins and is traditionally considered to be species poor. Here, we assessed the diversity of the nano-sized eukaryotic microbial wintertime community, using molecular ecological methods based on sequencing of small-subunit ribosomal RNA gene clone libraries. The results demonstrate that a rich community of small eukaryotes inhabits the Baltic Sea ice and water during winter. The community was dominated by alveolates and stramenopiles. Ciliates and cercozoans were the richest groups present, while in contrast to previous studies, diatoms showed a lower richness than expected. Furthermore, fungi and parasitic Syndiniales were present both in the water and in the sea ice. Some of the organisms in the sea-ice community were active, based on the RNA data, but a number of organisms were inactive or remnants from the freezing process. The results demonstrate that the sea-ice communities in the Baltic Sea are highly diverse and that water and ice of different ages include different protistan assemblages. Our study emphasizes the potential loss in biodiversity through diminishing ice cover as a result of climate change. © 2011 Springer-Verlag.


Valkama E.,Natural Resources Institute Finland LUKE | Rankinen K.,Finnish Environmental Institute | Virkajarvi P.,LUKE | Salo T.,Natural Resources Institute Finland LUKE | And 2 more authors.
Agriculture, Ecosystems and Environment | Year: 2016

The soil surface balance of nitrogen (N), calculated as the difference between N inputs and output (harvested yield), is a principal agri-environmental indicator that provides information on the potential loss of N to surface or groundwater. Relevant models of yield response to N fertilization could prove helpful in minimizing N balance and simultaneously maintaining high-yield production. For this purpose, we used meta-analysis to quantitatively summarize 40 Finnish N fertilization experiments on perennial grass leys. These experiments took place on mineral and organic soils at 17 sites over the past five decades. We assessed the effect of inorganic N fertilization on grass yields and N balances, and further estimated the potential to reduce N input and N balances. Since the relationship between N balance and N leaching is often complex, we estimated the relationship by using the COUP model (Coupled heat and mass transfer model for soil-plant-atmosphere systems) and by reviewing the 12 Nordic studies on N leaching experiments involving lysimeters and drained field plots. Nitrogen applications, together with the grass yield with no added N (N0-yield), accounted for 80–95% of the variation in the yield response of perennial grass leys; with increasing N0-yield, the yield response dropped considerably. The developed yield response models can serve to construct a dynamic tool for growers to adjust N applications for maximizing economic profitability. However, such a tool would require growers to estimate the magnitude of N0-yields on their fields by, for example, leaving some representative areas unfertilized for a few years. The N balance of grass leys linearly correlated with N input in fertilizer (R2 = 0.86–0.88), and an increase of 10 kg ha−1 in fertilization was associated with a 4.8 and 6.4 kg ha−1 increase in the N balances in mineral and organic soils, respectively. Otherwise N fertilization affected the N balance consistently across the studies. Evidently, adjusting fertilization to attain the economic optimum according to the developed models may reduce N fertilization, particularly when N0-yield is high, and thus lower the N balances for perennial grass leys. However, concerns about the risk of N leaching losses when using only inorganic N fertilization seems less crucial due to its low level and weak association with N balances. Even vigorous drops in N input and N balance would result only in minor reduction of N leaching loss, by a maximum of 3 kg ha−1 yr−1 in mineral soils. © 2016 Elsevier B.V.


Vaananen K.,University of Eastern Finland | Kauppila T.,Geological Survey of Finland | Makinen J.,Geological Survey of Finland | Leppanen M.T.,Finnish Environmental Institute | And 2 more authors.
Integrated Environmental Assessment and Management | Year: 2016

The mining industry is a common source of environmental metal emissions, which cause long-lasting effects in aquatic ecosystems. Metal risk assessment is challenging due to variations in metal distribution, speciation, and bioavailability. Therefore, seasonal effects must be better understood, especially in boreal regions in which seasonal changes are large. We sampled 4 Finnish lakes and sediments affected by mining for metals and geochemical characteristics in autumn and late winter, to evaluate seasonal changes in metal behavior, the importance of seasonality in risk assessment, and the sensitivity and suitability of different risk assessment methods. We compared metal concentrations in sediment, overlying water, and porewater against environmental quality guidelines (EQGs). We also evaluated the toxicity of metal mixtures using simultaneously extracted metals and an acid volatile sulfides (SEM-AVS) approach together with water quality criteria (US Environmental Protection Agency equilibrium partitioning benchmarks). Finally, site-specific risks for 3 metals (Cu, Ni, Zn) were assessed using 2 biotic ligand models (BLMs). The metal concentrations in the impacted lakes were elevated. During winter stratification, the hypolimnetic O2 saturation levels were low (<6%) and the pH was acidic (3.5–6.5); however, abundant O2 (>89%) and neutral pH (6.1–7.5) were found after the autumnal water overturn. Guidelines were the most conservative benchmark for showing an increased risk of toxicity in the all of the lakes. The situation remained stable between seasons. On the other hand, SEM-AVS, equilibrium partition sediment benchmarks (ESBs), and BLMs provided a clearer distinction between lakes and revealed a seasonal variation in risk among some of the lakes, which evidenced a higher risk during late winter. If a sediment risk assessment is based on the situation in the autumn, the overall risk may be underestimated. It is advisable to carry out sampling and risk assessment during periods in which metals are assumed to be the most environmentally harmful. Integr Environ Assess Manag 2016;12:759–771. © 2015 SETAC. © 2015 SETAC


Kuusisto E.,Finnish Environmental Institute
Lecture Notes in Earth Sciences | Year: 2012

The hydrological cycle is by far the largest material cycle of the Earth. The intensity of this cycle varies considerably as a function of time and space. Its annual volume has been fairly constant, but climate change is going to enhance the cycle, at the same time redistributing the temporal and spatial variability. This may have tremendous consequences both for nature and mankind. The majority of global climate models suggest, unfortunately, that many areas with scarce water resources will get drier in the future. On the other hand, in high latitudes where there already is plenty of water, more abundant water resources may be anticipated. © 2012 Springer-Verlag Berlin Heidelberg.


PubMed | University of Eastern Finland, Finnish Environmental Institute and Geological Survey of Finland
Type: Journal Article | Journal: Integrated environmental assessment and management | Year: 2016

The mining industry is a common source of environmental metal emissions, which cause long-lasting effects in aquatic ecosystems. Metal risk assessment is challenging due to variations in metal distribution, speciation, and bioavailability. Therefore, seasonal effects must be better understood, especially in boreal regions in which seasonal changes are large. We sampled 4 Finnish lakes and sediments affected by mining for metals and geochemical characteristics in autumn and late winter, to evaluate seasonal changes in metal behavior, the importance of seasonality in risk assessment, and the sensitivity and suitability of different risk assessment methods. We compared metal concentrations in sediment, overlying water, and porewater against environmental quality guidelines (EQGs). We also evaluated the toxicity of metal mixtures using simultaneously extracted metals and an acid volatile sulfides (SEM-AVS) approach together with water quality criteria (US Environmental Protection Agency equilibrium partitioning benchmarks). Finally, site-specific risks for 3 metals (Cu, Ni, Zn) were assessed using 2 biotic ligand models (BLMs). The metal concentrations in the impacted lakes were elevated. During winter stratification, the hypolimnetic O2 saturation levels were low (<6%) and the pH was acidic (3.5-6.5); however, abundant O2 (>89%) and neutral pH (6.1-7.5) were found after the autumnal water overturn. Guidelines were the most conservative benchmark for showing an increased risk of toxicity in the all of the lakes. The situation remained stable between seasons. On the other hand, SEM-AVS, equilibrium partition sediment benchmarks (ESBs), and BLMs provided a clearer distinction between lakes and revealed a seasonal variation in risk among some of the lakes, which evidenced a higher risk during late winter. If a sediment risk assessment is based on the situation in the autumn, the overall risk may be underestimated. It is advisable to carry out sampling and risk assessment during periods in which metals are assumed to be the most environmentally harmful. Integr Environ Assess Manag 2016;12:759-771. 2015 SETAC.


PubMed | Finnish Environmental Institute
Type: Journal Article | Journal: Ambio | Year: 2010

For more than a decade, anthropogenic sulfur (S) and nitrogen (N) deposition has been identified as a key pollutant in the Arctic. In this study new critical loads of acidity (S and N) were estimated for terrestrial ecosystems north of 60 degrees latitude by applying the Simple Mass Balance (SMB) model using two critical chemical criteria (Al/Bc = 1 and ANCle = 0). Critical loads were exceeded in large areas of northern Europe and the Norilsk region in western Siberia during the 1990s, with the more stringent criterion (ANCle = 0) showing the larger area of exceedance. However, modeled deposition estimates indicate that mean concentrations of sulfur oxides and total S deposition within the Arctic almost halved between 1990 and 2000. The modeled exceeded area is much reduced when currently agreed emission reductions are applied, and almost disappears under the implementation of maximum technically feasible reductions by 2020. In northern North America there was no exceedance under any of the deposition scenarios applied. Modeled N deposition was less than 5 kg ha(-1) y(-1) almost across the entire study area for all scenarios; and therefore empirical critical loads for the eutrophying impact of nitrogen are unlikely to be exceeded. The reduction in critical load exceedances is supported by observed improvements in surface water quality, whereas the observed extensive damage of terrestrial vegetation around the mining and smelter complexes in the area is mainly caused by direct impacts of air pollution and metals.

Loading Finnish Environmental Institute collaborators
Loading Finnish Environmental Institute collaborators