Browsing by Subject "saastuminen"

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  • Luoma, Emilia; Laurila-Pant, Mirka; Altarriba, Elias; Nevalainen, Lauri; Helle, Inari; Granhag, Lena; Lehtiniemi, Maiju; Srėbalienė, Greta; Olenin, Sergej; Lehikoinen, Annukka (Elsevier BV, 2022)
    Science of The Total Environment
    Biofouling of ship hulls form a vector for the introduction of non-indigenous organisms worldwide. Through increasing friction, the organisms attached to ships' hulls increase the fuel consumption, leading to both higher fuel costs and air emissions. At the same time, ship biofouling management causes both ecological risks and monetary costs. All these aspects should be considered case-specifically in the search of sustainable management strategies. Applying Bayesian networks, we developed a multi-criteria decision analysis model to compare biofouling management strategies in the Baltic Sea, given the characteristics of a ship, its operating profile and operational environment, considering the comprehensive environmental impact and the monetary costs. The model is demonstrated for three scenarios (SC1-3) and sub-scenarios (A-C), comparing the alternative biofouling management strategies in relation to NIS (non-indigenous species) introduction risk, eco-toxicological risk due to biocidal coating, carbon dioxide emissions and costs related to fuel consumption, in-water cleaning and hull coating. The scenarios demonstrate that by the careful consideration of the hull fouling management strategy, both money and environment can be saved. We suggest biocidal-free coating with a regular in-water cleaning using a capture system is generally the lowest-risk option. The best biocidal-free coating type and the optimal in-water cleaning interval should be evaluated case-specifically, though. In some cases, however, biocidal coating remains a justifiable option.
  • Huurtomaa, Satu (Helsingin yliopisto, 2019)
    The Baltic Sea is a vulnerable marine environment and susceptible to pollution. The situation is especially severe in the Gulf of Finland due to a large catchment area compared to the size of the Gulf. The north eastern Gulf of Finland has been described as one of the most contaminated areas of the entire Baltic Sea, with extensive pollution load via river Kymi in the past. Still today, the currents bring contaminants from the eastern part of the Gulf – the Neva estuary and the Bay of Viborg. The concentrations of V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, Sb, Hg, Pb, Bi and La were studied in the surface sediments and three GEMAX cores. The vertical distribution revealed the temporal change in the metal accumulation. The spike in the Cs concentration, indicating the Chernobyl disaster in 1986, enabled the estimation of the accumulation of studied elements over time. The horizontal distribution maps based on the concentrations in the surface sediments enabled the discovery of the sites with most intense metal accumulation. Correlation coefficients showed the effect of carbon and sediment grain size in the distribution of metals. The comparison of the metal concentrations to the natural background levels and the Canadian sediment quality guidelines (SQGs) enabled the estimation of the degree of contamination of the area. The metal concentrations have declined during the last decades in the north eastern Gulf of Finland, indicating lower contamination input towards present day. However, in the oxidized Ravijoki core, the decline was not that obvious, probably due to metal scavenging by Fe and Mn oxides and bioturbation. The regional metal distribution was strongly affected by the grain size and carbon – most metals showed high positive correlations with carbon and finer sediment fraction. Mn was an exception, showing negative correlations with both carbon and clay, probably due to the Mn reduction at sites with high organic matter accumulation. The regional distribution pattern suggested main Cd pollution arriving from the eastern part of the Gulf. The distribution of Hg, Mo, Cu and Zn also suggested a possible source in the east. High concentrations of Hg, Pb and Cu were discovered in the outlets of river Kymi. According to the Canadian SQGs, the sediments in the north-eastern Gulf of Finland were contaminated. The situation is especially severe in the case of Zn – the higher reference value PEL, above which adverse biological effects frequently occur, was exceeded even in the oxidized Ravijoki sediments. The highest concentrations of the elements with defined SQGs (Cd, Cr, Zn, Cu, Hg, Pb and As) exceeded the lower reference values in the surface sediments, indicating that all these metals could, at least locally, pose a severe threat to benthic species.
  • Hukka, Eeva (2001)
    Pro gradu -tutkielmani tarkoituksena on soveltaa James Grunigin tilanneteoriaa käytäntöön ja perehtyä grunigilaisen aktiivisen ryhmittymän viestintään. Niin ikään tavoitteena on tarkastella aktiivista ryhmittymää sen vastapuolen, ryhmittymän huolenaiheen synnyttäneen työyhteisön, näkökulmasta. Tilanneteorian mukaan määritelty aktiivinen ryhmittymä löytyi Helsingin Myllypurosta, Alakiventie 8:sta. Aktiivisena ryhmittymänä "kasitalojen" asukkaita yhdistää yhteinen huolenaihe: heidän kotipihaltaan on löytynyt vanhalta kaatopaikalta peräisin olevia myrkkyjä, joiden vuoksi Helsingin kaupunki aikoo purkaa heidän kotinsa. Huoli terveydestä ja omaisuuden arvosta ovat saaneet kasitalolaiset toimimaan ongelman ratkaisemiseksi. Selvitin tutkielmassani alakiventieläisen ryhmittymän viestintää ja sen merkitystä ryhmittymälle. Pääasiallisena tutkimusaineistona olivat asukkaiden teemahaastattelut. Tutkielmassa kävi ilmi, että kasitalolaiset ovat käsitelleet myrkkyongelmaa aktiivisesti lähiverkoissaan ja että he ovat käyttäneet keskusteluja lähipiirinsä kanssa myrkkyongelman analysoimiseen. Lisäksi he ovat etsineet lähiverkoistaan tietoa. Kasitalolaiset ovat kehittäneet myrkkyongelman myötä myös aivan uusia, varta vasten myrkkyongelman ratkaisemiseksi kehitettyjä viestinnän muotoja, jotka ovat auttaneet heitä pyrkimään tavoitteisiinsa monin eri tavoin. Helsingin kaupungin näkökulmasta perehdyin aktiiviseen ryhmittymään yhteisöviestinnän kohderyhmänä. Tässä yhteydessä keskeisenä tutkimusaineistona olivat asukkaiden ja Helsingin kaupungin edustajien teemahaastattelut sekä kaupungin tiedotteet ja asukkaille lähetetyt kirjeet. Alakiventien myrkkytapaus osoitti, että epäjohdonmukainen tiedottaminen ei lisää aktiivisen ryhmittymän luottamusta, eikä myöskään se, jos ryhmittymän tiedon tarpeisiin ei vastata. Kasitalolaisten vilkas lähiverkkoviestintä merkitsee kaupungin näkökulmasta puolestaan sitä, että jokaisen ryhmittymän kanssa keskustelevan kaupungin edustajan merkitys viestijänä on keskeinen. Tämä tuo haasteita kaupungin sisäiseen viestintään. Tutkielmani tärkeimpiä lähteitä olivat haastattelujen lisäksi seuraavat teokset: Grunig, James (1992): Excellence in Public Relations Management; Grunig, James ja Hunt, Todd (1984): Managing Public Relations; Heath, Robert (1988): Strategic Issues Management; Åberg, Leif (2000): Viestintä kolmannen sektorin kansalaisyhteisössä. Teoksessa Aula, Pekka ja Hakala, Salli (toim.): Kolmet kasvot. Näkökulmia organisaatioviestintään.
  • Coppock, Rachel L.; Lindeque, Penelope K.; Cole, Matthew; Galloway, Tamara S.; Nakki, Pinja; Birgani, Hannah; Richards, Saskiya; Queirós, Ana M. (Elsevier, 2021)
    Journal of Hazardous Materials 415: 125583
    Microplastics are ubiquitous in the marine environment, however, the mechanisms governing their uptake by, and burial within, seabed habitats are poorly understood. In this study, microplastic burial and its impact on fauna-mediated sedimentary processes was quantified at three coastal sites, and the potential contribution of burrowing faunal communities to this process assessed via functional trait diversity analysis of field data. In addition, laboratory exposures were used to assess whether sediment-processing undertaken by the brittlestar Amphiura filiformis, a key species in the sampled area, could explain the burial of microplastic fibres. Field observations confirmed broad-scale burial of microplastics across the coastal seabed, consistent across sites and seasons, with microplastic sequestration linked to benthic-pelagic exchange pathways, driven by burrowing fauna. Brittlestars were observed to bury and line their burrow walls with microfibres during experiments, and their burial activity was also modified following exposure to nylon fibres, relative to controls. Collectively, these results indicate that biodiverse and functionally important seabed habitats act as microplastic sinks, with burrowing fauna contributing to this process via well-known benthic-pelagic pathways, the rates of which are modified by plastic exposure.
  • Hashemi, Fatemeh; Pohle, Ina; Pullens, Johannes W. M; Tornbjerg, Henrik; Kyllmar, Katarina; Marttila, Hannu; Lepistö, Ahti; Klove, Bjorn; Futter, Martyn; Kronvang, Brian (MDPI, 2020)
    Water 12 6 (2020)
    Optimal nutrient pollution monitoring and management in catchments requires an in-depth understanding of spatial and temporal factors controlling nutrient dynamics. Such an understanding can potentially be obtained by analysing stream concentration–discharge (C-Q) relationships for hysteresis behaviours and export regimes. Here, a classification scheme including nine different C-Q types was applied to a total of 87 Nordic streams draining mini-catchments (0.1–65 km2). The classification applied is based on a combination of stream export behaviour (dilution, constant, enrichment) and hysteresis rotational pattern (clock-wise, no rotation, anti-clockwise). The scheme has been applied to an 8-year data series (2010–2017) from small streams in Denmark, Sweden, and Finland on daily discharge and discrete nutrient concentrations, including nitrate (NO3−), total organic N (TON), dissolved reactive phosphorus (DRP), and particulate phosphorus (PP). The dominant nutrient export regimes were enrichment for NO3− and constant for TON, DRP, and PP. Nutrient hysteresis patterns were primarily clockwise or no hysteresis. Similarities in types of C-Q relationships were investigated using Principal Component Analysis (PCA) considering effects of catchment size, land use, climate, and dominant soil type. The PCA analysis revealed that land use and air temperature were the dominant factors controlling nutrient C-Q types. Therefore, the nutrient export behaviour in streams draining Nordic mini-catchments seems to be dominantly controlled by their land use characteristics and, to a lesser extent, their climate.
  • Lyytimäki, Jari; Assmuth, Timo (Springer Nature, 2015)
    GeoJournal 80, 113–127 (2015)
    Securing high-quality potable water is a key challenge for all societies. The question is not only about water availability and quality determined by hydrological, chemical, and biological factors, or technologies and monetary assets, but also about various cultural, social, and political factors that together constitute so-called hydro-social cycles. We focus on risk communication and management, in connection with the debates on planning and construction of an artificial groundwater recharge system in the Virttaankangas esker, aiming to provide potable water for the region of Turku, southwest Finland. Based on print media coverage, online debate, and comments on the environmental impact assessment report, we identify key themes and framings of risk debates and discuss which elements of the hydro-social cycle are prone to be highlighted or omitted. Our results show how different framings of risks and benefits are represented with regard to geography, time span, causative agents, impact types, those exposed, alternative management options, and uncertainties involved. Representations created both by traditional print media and new social media polarise the debate. The adoption of the concept of the hydro-social cycle in planning and communication processes may help in understanding and alleviating polarisation.
  • Turunen, Jarno; Karppinen, Anssi; Ihme, Raimo (Springer, 2019)
    SN Applied Sciences 1, 210 (2019)
    Agricultural diffuse pollution is a major environmental problem causing eutrophication of water bodies. Despite the problem is widely acknowledged, there has been relatively few major advances in mitigating the problem. We studied the effectiveness of biopolymer-based (tannin, starch, chitosan) natural coagulants/flocculants in treatment of two different agricultural wastewaters that differed in their level of phosphorus pollution and turbidity. We used jar-tests to test the effectiveness of the biopolymer coagulants in reducing water turbidity, total phosphorus, and total organic carbon (TOC) from the wastewaters. In more polluted water (total phosphorus: 300 µg/L, turbidity: 130 FNU, TOC: 30 mg/L), all tested biopolymers performed well. The best reductions for different biopolymer coagulants were 64–95%, 80–98% and 14–27%, for total phosphorus, turbidity and TOC, respectively. Tannin and chitosan coagulants performed the best at doses of 5–10 mL/L, whereas starch coagulants had the best performance at 1–2 mL/L doses. Tannin and chitosan coagulants performed clearly better than the starch coagulants. In less polluted water (total phosphorus: 74 µg/L, turbidity: 3.9 FNU, TOC: 21 mg/L), chitosan and starch coagulants did not produce flocs at any of the tested doses. Tannin coagulant performed the best at doses of 5–8 mL/L, where reductions were 70%, 82%, and 22%, for total phosphorus, turbidity and TOC, respectively. The great reductions of phosphorus and turbidity suggests that biopolymer coagulants could be applied in treatment of agricultural water pollution. The high phosphorus retention in the biodegradable biopolymer sludge suggests that the sludge can be readily used as a phosphorus fertilizer, which would aid the recycling of nutrients.
  • Macura, Biljana; Piniewski, Mikolaj; Ksiezniak, Marta; Osuch, Pawel; Haddaway, Neal R.; Ek, Filippa; Andersson, Karolin; Tattari, Sirkka (Springer Nature, 2019)
    Environmental Evidence 8, 39 (2019)
    Background Agriculture is the main sector responsible for nutrient emissions in the Baltic Sea Region and there is a growing pressure to identify cost-effective solutions towards reducing nitrogen and phosphorus loads originating from farming activities. Recycling resources from agricultural waste is central to the idea of a circular economy, and has the potential to address the most urgent problems related to nutrients use in the food chain, such as depletion of natural phosphorus reserves, water pollution and waste management. This systematic map examined what evidence exists relating to the effectiveness of ecotechnologies in agriculture for the recovery and reuse of carbon and/or nutrients (nitrogen and phosphorus) in the Baltic Sea region and other comparable boreo-temperate systems. Methods We searched for both academic and grey literature. English language searches were performed in 5 bibliographic databases and search platforms, and Google Scholar. Searches in 36 specialist websites were performed in English, Finnish, Polish and Swedish. The searches were restricted to the period 2013 to 2017. Eligibility screening was conducted at two levels: title and abstract (screened concurrently for efficiency) and full text. Meta-data was extracted from eligible studies including bibliographic details, study location, ecotechnology name and description, type of outcome (i.e. recovered or reused carbon and/or nutrients), type of ecotechnology in terms of recovery source, and type of reuse (in terms of the end-product). Findings are presented here narratively and in a searchable database, and are also visualised in a web-based evidence atlas (an interactive geographical information system). In addition, knowledge gaps and clusters have been identified in the evidence base and described in detail. Results We found 173 articles studying the effectiveness of 177 ecotechnologies. The majority of eligible articles were in English, originated from bibliographic databases and were published in 2016. Most studies with reported locations, and given our boreo-temperate scope, were conducted in Europe and North America. The three most prevalent ecotechnologies in the evidence base (collectively 40.7%) were; soil amendments, anaerobic digestion and (vermi)composting. Manure was the principal waste source used for recovery of nutrients or carbon, making up 55.4% of the all studies in evidence base, followed by a combination of manure and crop residues (22%). There were 51 studies with 14 ecotechnologies that reported on recovery of carbon and nutrients together, predominantly via (vermi)composting and anaerobic digestion. Only 27 studies focused on reuse of recovered nutrients and carbon through soil amendments. Conclusions This systematic map report provides an evidence base that can be useful for researchers and decision-makers in policy and practice working on transformation from linear to circular economy in the agricultural waste sector. Three potential topics for future systematic reviews are: (1) effectiveness of products recovered from different types of agricultural wastes as soil amendments or fertilizers; (2) effectiveness of anaerobic digestion as an ecotechnology used for recovery of nutrients and carbon; (3) effectiveness of composting and/or vermicomposting as ecotechnologies used for recovery of nutrients and carbon.
  • Fritze, Hannu (Suomen metsätieteellinen seura, 1992)
  • Taka, Maija; Sillanpää, Nora; Niemi, Tero; Warsta, Lassi; Kokkonen, Teemu; Setälä, Heikki (Elsevier, 2022)
    Science of the total environment
    Urban hydrology is characterized by increased runoff and various pollutant sources. We studied the spatio-temporal patterns of stormwater metal (Al, V, Cr, Mn, Fe, Cu, Zn, and Pb) concentrations and loads in five urbanized and one rural catchment in Southern Finland. The two-year continuous monitoring revealed a non-linear seasonal relationship between catchment urban intensity and metal export. For runoff, seasonal variation decreased with increasing imperviousness. The most urbanized catchments experienced greatest temporal variation in metal concentrations: the annual Cu and Zn loads in most of the studied urbanized catchments were up to 86 times higher compared to the rural site, whereas Fe loads in the urbanized catchments were only circa 29% of the rural load. Total metal levels were highest in the winter, whereas the winter peak of dissolved metal concentrations was less pronounced. The collection of catchment characteristics explained well the total metal concentrations, whereas for the dissolved concentrations the explanatory power was weaker. Our catchment-scale analysis revealed a mosaic of mainly diffuse pollutant sources and calls for catchment-scale management designs. As urban metal export occurred across seasons, solutions that operate also in cold conditions are needed. Highlights • Impact of urban land use on metal export was studied by monitoring six catchments. • Continuous monitoring, automatic sampling and statistical modelling were performed. • Urban intensity increased seasonality in concentrations, especially for Zn and Cu. • Highest total metal load occurred in winter; seasonality in dissolved metals was modest.
  • Unknown author (Vesihallitus, 1972)
    Vesihallitus. Tiedotus 28
  • Laukkanen, Johanna; Takaluoma, Esther; Runtti, Hanna; Mäkinen, Jari; Kauppila, Tommi; Hellsten, Seppo; Luukkonen, Tero; Lassi, Ulla (Springer Science and Business Media LLC, 2022)
    Journal of Soils and Sediments
    Purpose Adsorbent amendment to contaminated sediments is one in situ remediation method to decrease the bioaccessibility of pollutants from the sediments. In this work, alkali-activated blast furnace slag (BFS) granules were used in a field experiment at Lake Kivijärvi (Finland). The lake was heavily affected by a mining accident in 2012, which released a significant peak load of metals and sulfate. The purpose of this work was to evaluate the performance of the novel amendment material for in situ remediation in real conditions with a preliminary cost estimation. Methods Alkali-activated BFS granules were prepared and characterized for composition, microstructure, and surface properties. Two mesocosms were placed in the lake: one with granule dosing and another without. Sediment and pore water samples were collected after a two-week period. Similar small-scale experiment was performed in laboratory with a three-month duration. Bioaccessibility of metals from sediments was assessed with a three-stage leaching procedure. Results The granules were effective in decreasing the mobility of Fe, Zn, Ni, and Cr in all leaching stages by approximately 50–90% in comparison with unamended sediment in the mesocosm experiment. Laboratory-scale incubation experiments also indicated decreased release of Ba, Co, Ni, Al, Fe, Mg, Mn and S. The estimated material costs were lower than the removal of the contaminated sediments with dredging and off-site treatment. Conclusion The results showed preliminarily the effectiveness of alkaline-activated BFS in the remediation of metal-contaminated sediments in a field experiment. However, topics requiring further study are the leaching of trace elements from the material and impact on the sediment pH.
  • Bergström, Irina; Mäkelä, Katariina; Starr, Michael (Ministry of the Environment, 1995)
    Ministry of the Environment, Environmental Policy Department; Report 1/1995
  • Savander-Lehtinen, Helena (Helsingfors universitet, 2016)
    Kiinnostuin aluksi Vanhan testamentin Gen.6.1–6 tekstistä, jossa jumalain pojat näkevät maan kauniit tyttäret ja ihastuvat heihin. Teksti jäi kuitenkin torsoksi ja jatkoin 1 Henokin kirjan 1–36 kertomuksella, josta löysin tutkimukseeni sopivia tekstejä. Tutkin miten näissä työhöni mukaan ottamissa teksteissä esiintyy kauneus, seksuaalisuus ja millaisia ovat niiden mahdolliset seuraamukset sekä mistä nämä käsitykset tulevat. Miksi kauneus mainitaan molemmissa teksteissä? Olisivathan kirjoittajat voineet olla käyttämättä adjektiivia kaunis ja kirjoittaa ainoastaan, että jumalien pojat näkivät ihmisten tyttäret ja jatkaa kertomusta sitten siitä eteenpäin. Pro graduni on temaattinen, mutta olen poiminut tutkimuskysymykseni avautumiseen osia erilaisista tutkimusmenetelmistä. 1 Henok kirjan 1-16 eli Valvojaenkelien kirjan valitut tekstit olen kääntänyt suomeksi Nickelsburgin englanninkielisestä tekstistä. Tekstejä tutkiessani olen ottanut huomioon sen, että tapahtumilla on myös aina taustansa. Toisen temppelin ajan yhteiskunta- ja perherakenteet sekä naisten asema taustoittavat siten myös aihettani. Heprealaisen raamatun kirjoittaminen on tapahtunut Babyloniasta palaamisen jälkeen ja sen tekstejä on editoitu vielä toisen vuosisadan eaa. jälkeen ja näin naisen aseman tarkka rajaus ennen ja jälkeen Toisen temppelin ajan aikakausille on vaikeaa. Selvittelen millaisia tuon ajan yhteisön ja kulttuurin moraalikäsityksiä liittyy kauneuteen ja seksuaalisuuteen. Se, että tekstissä kerrotaan jostain naisesta, ei se tarkoita, että kaikki naiset olisivat samanlaisia. Niin antiikin kreikkalaisissa teksteissä kuin myös Raamatun teksteissä käytetään naisstereotypioita kuvaamaan tiettyjä ominaisuuksia. Kauneutta on kautta aikojen ja kulttuurien käsitelty joko hyveenä tai negatiivisena ominaisuutena. Nainen on saanut ylistystä kauneutensa vuoksi jo muinaisissa kreikkalaisissa tarustoissa. Näissä tarustoissa jumalat huomasit kauniit naiset ja ottivat heidät lemmenkumppaneiksi. Näin kerrotaan myös Vartijaenkelien kirjassa, jossa asia on esitetty ”raamatullisemmin” eli piilotellummin. Genesis 6:2 ja 1 Henokin kirja 6:1 kertovat kumpikin näissä kohdissaan, että valitut naiset olivat kauniita. Kun jumalien pojat näkevät 1 Henokin kirjassa maan tyttärien olevan erityisen kauniita, niin heissä herää halu maata heidät ja tehdä heidän kanssaan jälkeläisiä. Kauneus houkuttelee näin taivaallista väkeä ja he sortuvat erilaisiin kiellettyihin tekoihin kuolevaisten naisiin yhtymisen lisäksi. Seksuaalisuus esiintyy siten näissä tutkimissani teksteissä voimakkaasti, osin peiteltynä osin hyvinkin selkokielisesti. Kertomuksen tunnuspiirteinä ovat haluaminen, synnyttäminen, vaimoksi ottaminen, tahrautuminen, joka käsittää myös naisten epäpuhtauden ja veren ja naisten makaamisen. Naisten opettaminen käyttämään esimerkiksi kosmetiikkaa on kirjoittajan tapa kuvata negatiivisia vaikutuksia. Tarinassa on ikiaikainen ajatus naisesta synnin tekijänä, vaikka nämä miehen muodon ottaneet enkelit olivat osasyyllisiä tapahtuneeseen. Naisen rikkeitä ovat kaunistautuminen, vietteleminen ja seksuaalisuus, jolla hän saastuttaa miehen puvussa olevan Valvojaenkelin ja ajaa miehen turmioon. Naisen osana kuului näiden kirjoitusten aikakausina olla hyvä neitseellinen tytär, jolle kotitalous valitsee puolison, hyvä ja ahkera puoliso, joka ei turhaan ole kauneuden perään. Hän hoitaa kotitalouden työt ja synnyttää lapset ja on kuuliainen miehelleen.
  • Annila, Erkki (Suomen metsätieteellinen seura, 1989)
  • Uurasjärvi, Emilia; Hartikainen, Samuel; Setälä, Outi; Lehtiniemi, Maiju; Koistinen, Arto (John Wiley & Sons, 2019)
    Water Environment Research
    We examined microplastic concentrations, size distributions, and polymer types in surface waters of a northern European dimictic lake. Two sampling methods, a pump sieving water onto filters with different pore sizes (20, 100, and 300 µm) and a common manta trawl (333 µm), were utilized to sample surface water from 12 sites at the vicinity of potential sources for microplastic emissions. The number and polymer types of microplastics in the samples were determined with optical microscopy and μFTIR spectroscopy. The average concentrations were 0.27 ± 0.18 (mean ± SD) microplastics/m3 in manta trawled samples and 1.8 ± 2.3 (>300 μm), 12 ± 17 (100–300 μm) and 155 ± 73 (20–100 μm) microplastics/m3 in pump filtered samples. The majority (64%) of the identified microplastics (n = 168) were fibers, and the rest were fragments. Materials were identified as polymers commonly used in consumer products, such as polyethylene, polypropylene, and polyethylene terephthalate. Microplastic concentrations were high near the discharge pipe of a wastewater treatment plant, harbors, and snow dumping site.
  • Lehtonen, Kari K.; d'Errico, Giuseppe; Korpinen, Samuli; Regoli, Francesco; Ahkola, Heidi; Kinnunen, Tanja; Lastumäki, Anu (Frontiers Media S.A., 2019)
    Frontiers in Marine Science
    Contamination status of coastal areas of Finland (northern Baltic Sea) markedly affected by anthropogenic activities (harbors, shipyards and maritime activity, industry, municipal and agricultural inputs, legacy contamination) was assessed for the first time using the weight of evidence (WOE) approach. The key element of the study was the caging (transplantation) of Baltic mussels (Mytilus trossulus) for the measurement of tissue accumulation of polycyclic aromatic hydrocarbons (PAHs) and applying a suite of biomarkers of biological effects of contaminants. Additional variables included in the assessment were trace metals in seawater, macrozoobenthos, near-bottom oxygen levels and eutrophication indicators. The chemical parameters were supported by passive sampling of PAHs and organotins at the study sites. The integrated approach combining all the line of evidence (LOE) variables into the WOE showed separation of some sites as more affected by hazardous substances than others, with the most contaminated areas found around harbor and ship yard areas. The contaminant levels measured in the different matrices were not alarmingly high at none of the areas compared to many other areas within or outside the Baltic Sea under more heavy anthropogenic impact, rarely exceeding any given threshold values for Good Environmental Status of the EU Marine Strategy Framework Directive. However, significant biological effects were recorded in mussels in the most contaminated sites, signifying that the combined effects caused by the contaminants and other environmental factors are disturbing the health of marine organisms in the area. The results of this successful combined application based on the mussel transplantation method and the WOE approach are highly encouraging for further trials in developing the monitoring of chemical contamination in the Baltic Sea.
  • Westerlund, Antti; Miettunen, Elina; Tuomi, Laura; Alenius, Pekka (Copernicus GmbH, 2022)
    Ocean Science
    Water exchange through the Åland Sea (in the Baltic Sea) greatly affects the environmental conditions in the neighbouring Gulf of Bothnia. Recently observed changes in the eutrophication status of the Gulf of Bothnia may be connected to changing nutrient fluxes through the Åland Sea. Pathways and variability of sub-halocline northward-bound flows towards the Bothnian Sea are important for these studies. While the general nature of the water exchange is known, that knowledge is based on only a few studies that are somewhat limited in detail. Notably, no high-resolution modelling studies of water exchange in the Åland Sea area have been published. In this study, we present a configuration of the NEMO 3D hydrodynamic model for the Åland Sea–Archipelago Sea area at around 500 m horizontal resolution. We then use it to study the water exchange in the Åland Sea and volume transports through the area. We first ran the model for the years 2013–2017 and validated the results, with a focus on the simulated current fields. We found that the model reproduced current direction distributions and layered structure of currents in the water column with reasonably good accuracy. Next, we used the model to calculate volume transports across several transects in the Åland Sea. These calculations provided new details about water transport in the area. Time series of monthly mean volume transports showed consistent northward transport in the deep layer. In the surface layer there was more variability: while net transport was towards the south, in several years some months in late summer or early autumn showed net transport to the north. Furthermore, based on our model calculations, it seems that dynamics in the Lågskär Deep are more complex than has been previously understood. While Lågskär Deep is the primary route of deep-water exchange, a significant volume of deep water still enters the Åland Sea through the depression west of the Lågskär Deep. Better spatial and temporal coverage of current measurements is needed to further refine the understanding of water exchange in the area. Future studies of transport and nutrient dynamics will eventually enable a deeper understanding of eutrophication changes in the Gulf of Bothnia.