Browsing by Subject "rikki"

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  • Syri, Sanna (Finnish Environment Institute, 2001)
    Monographs of the Boreal Environment Research 19
    This study presents the development and applications of regional and local scale models for use in integrated assessment of air pollution effects in conjunction with large-scale models. A regional deposition model called DAIQUIRI (Deposition, AIr QUality and Integrated Regional Information) for integrated assessment purposes in Finland was constructed, and regional matrices for nitrogen oxides and ammonia were developed from the results of the regional air quality model of the FMI. DAIQUIRI produced similar estimates of deposition from Finnish sources as the original model, and long-term trends and the average level of deposition estimated with DAIQUIRI were found comparable with the monitored deposition levels and trends. For the mid-nineties situation, the regional nitrogen modeling resulted in 9% to 19% (depending on the region compared) larger estimates of areas with acidity critical load exceedances than when using European scale nitrogen deposition modeling.In this work, also a method for estimating the impacts of local NOx emissions on urban and sub-urban ozone levels was developed and tested. The study concentrated on representing the destruction of ozone by fresh NO emissions in urban areas for future use in integrated assessment modeling of ozone control strategies. Correlation coefficients between measured daytime ozone values in the study area were found to improve from 0.64 (correlation between urban and surrounding rural measurements) to 0.85, on the average. The average correlation between daytime large-scale model estimates and urban site measurements was found to improve from 0.37 to 0.58.In the study, also integrated assessment model applications were carried out at European, national and local levels. The synergies between control strategies for CO2 and acidification and ozone formation in the case of the UN/FCCC Kyoto protocol and the air quality targets of the EU were assessed with the help of coupled models. With two alternative energy scenarios reflecting the Kyoto targets for CO2, reductions of sulfur and NOx emissions between 12% and 22% and 8% to 12%, respectively, were estimated by 2010 in the EU-15 with the present emission control legislation. Due to the lower activity levels generating less emissions and the cleaner energy forms used, 35-43% cost savings in further technical emission controls required for achieving the EU air quality targets would be achieved with the scenarios studied. Case studies for Finland indicated that there has been a decrease of 60% in the area at risk of acidification from 1990 to 1995, and that the declining trend is expected to continue due to the recent international emission reduction agreements within the UN/ECE and the EU. Implementation of the Kyoto protocol in Finland and in the whole of EU-15 (with the present emission legislation) could bring up to 8% more reduction of ecosystems at risk of acidification in Finland by 2010 than the recent UN/ECE protocol.An uncertainty analysis of acidification integrated assessment modeling in Finland indicated that critical loads dominate the uncertainty. Estimates are becoming more robust, as the general level of deposition is decreasing. In Finland, further efforts to reduce the overall uncertainty should be mainly directed to more accurate description of critical thresholds. In areas affected by major nearby emission sources, also uncertainties in emissions and deposition are significant. The models and their applications presented in this study contributed to identifying the problem characteristics and have supported environmental policy development at international, national and regional levels.
  • Kenttämies, Kaarle (Vesihallitus, 1979)
    Vesientutkimuslaitoksen julkaisuja 30, 42-45
    Tiivistelmä: Ilman rikkilaskeuma ja järvien happamoituminen Suomessa.
  • Forsius, Martin; Posch, Maximilian; Holmberg, Maria; Vuorenmaa, Jussi; Kleemola, Sirpa; Augustaitis, Algirdas; Beudert, Burkhard; Bochenek, Witold; Clarke, Nicholas; de Wit, Heleen A.; Dirnböck, Thomas; Frey, Jane; Grandin, Ulf; Hakola, Hannele; Kobler, Johannes; Krám, Pavel; Lindroos, Antti-Jussi; Löfgren, Stefan; Pecka, Tomasz; Rönnback, Pernilla; Skotak, Krzysztof; Szpikowski, Józef; Ukonmaanaho, Liisa; Valinia, Salar; Váňa, Milan (Elsevier, 2021)
    Science of The Total Environment 753 (2021), 141791
    Anthropogenic emissions of nitrogen (N) and sulphur (S) compounds and their long-range transport have caused widespread negative impacts on different ecosystems. Critical loads (CLs) are deposition thresholds used to describe the sensitivity of ecosystems to atmospheric deposition. The CL methodology has been a key science-based tool for assessing the environmental consequences of air pollution. We computed CLs for eutrophication and acidification using a European long-term dataset of intensively studied forested ecosystem sites (n = 17) in northern and central Europe. The sites belong to the ICP IM and eLTER networks. The link between the site-specific calculations and time-series of CL exceedances and measured site data was evaluated using long-term measurements (1990–2017) for bulk deposition, throughfall and runoff water chemistry. Novel techniques for presenting exceedances of CLs and their temporal development were also developed. Concentrations and fluxes of sulphate, total inorganic nitrogen (TIN) and acidity in deposition substantially decreased at the sites. Decreases in S deposition resulted in statistically significant decreased concentrations and fluxes of sulphate in runoff and decreasing trends of TIN in runoff were more common than increasing trends. The temporal developments of the exceedance of the CLs indicated the more effective reductions of S deposition compared to N at the sites. There was a relation between calculated exceedance of the CLs and measured runoff water concentrations and fluxes, and most sites with higher CL exceedances showed larger decreases in both TIN and H+ concentrations and fluxes. Sites with higher cumulative exceedance of eutrophication CLs (averaged over 3 and 30 years) generally showed higher TIN concentrations in runoff. The results provided evidence on the link between CL exceedances and empirical impacts, increasing confidence in the methodology used for the European-scale CL calculations. The results also confirm that emission abatement actions are having their intended effects on CL exceedances and ecosystem impacts.
  • Mäenpää, Jenni (Helsingin yliopisto, 2020)
    Wines are treated to ensure their quality and preservation in the winemaking process. Treatments also have their drawbacks. Premium winemakers have often avoided filtration because it is supposed to cause a loss of taste. Sulfurization of wine is important, for example, for microbiological quality, but it is assumed to reduce the fruity aroma of wines. The purpose of the literature section was to investigate in general the effects of the wine-making process on the volatile compounds of wines. The interest was to find out what happens in winemaking and what compounds are formed at different stages of the process. The literature section also looked at volatile compounds, their analytics and SPME technology. The aim of the experimental part of the work was to develop a research method using headspace-solidphasemicroextraction-gaschromatography-massspectrometry (HS-SPME-GC-MS) technology and to find out the aroma composition and possible differences of the receiving sample and the bag-in box (BIB) -packaged wine. Indicator compounds for volatile compounds were determined from Chardonnay and Cabernet Sauvignon wines using the HS-SPME-GC-MS method developed for the study of Cabernet Sauvignon wine. In the optimization of the method, the functionality of SPME fibers, the GC temperature program and the sample preparation were studied. Receipt, tank, and BIB packaging samples were collected for examination of the wines. The samples were analyzed by HS-SPME-GC-MS and the results were processed by principal component analysis (PCA) as well as other statistical methods. Receipt and BIB packaging samples from Cabernet Sauvignon wine were not divided into clear groups based on PCA. The model best describing the changes in the compounds was achieved with the profile of volatile compounds: ethyl acetate, 1-propanol, isoamyl alcohol, 2-methylbutanol, butanoic acid ethyl ester, isoamyl acetate, hexanol, hexanoic acid, octanoic acid ethyl ester and octanoic acid. In Cabernet Sauvignon wine, almost all the amounts of volatile compounds remained fairly constant as the process progressed. In 1-propanol, ethyl ester of butanoic acid and ethyl ester of octanoic acid, a decrease in the amount was observed between the receipt sample and the BIB packaging sample. In contrast, the amount of 2-methylbutanol and octanoic acid increased when receiving and BIB packaging samples were compared. Receipt and BIB packaging samples of Chardonnay wine were distinguished by PCA. The model best describing the changes in the compounds was achieved with the profile of volatile compounds: ethyl acetate, isoamyl alcohol, 3-methylbutanol, 2-methylbutanol, butanoic acid ethyl ester, isoamyl acetate, hexanol, hexanoic acid, benzene alcohol, octanoic acid ethyl ester, octanoic acid ethyl ester, octanoic acid ethyl ester. The amounts of volatile compounds studied in Chardonnay wine remained fairly constant. Octanoic acid ethyl ester, benzyl alcohol and decanoic acid decreased as the process. The results of the study show that the wine processing process affects the flavorings of Cabernet Sauvignon and Chardonnay wine. The HS-SPME-GC-MS method showed a reduction in several compounds, but previous studies have shown that this change has not been detected by sensory evaluation.
  • Molski, Boguslaw; Bytnerowicz, Andrzej; Dmuchowski, Wojciech (Suomen metsätieteellinen seura, 1981)
  • Sahra, Mia (Helsingin yliopisto, 2019)
    Kivennäis- ja hivenaineet ovat lypsylehmälle välttämättömiä elintoimintojen ja tuotannon ylläpitoon. Härkäpavun siementä voidaan käyttää valkuaisen lähteenä ja koko kasvustoa säilörehuna, mutta niiden hivenainekoostumusta ei tunneta yhtä hyvin kuin rypsirouheen ja nurmisäilörehun. Tutkimuksessa verrattiin lypsylehmän kivennäis- ja hivenaineiden saantia ja sulavuutta härkäpapusäilörehusta ja härkäpavun siemenestä nurmisäilörehuun ja rypsirouheeseen. Tutkielmassa tarkasteltiin kahta koetta, jotka oli tehty Viikin opetus- ja tutkimustilalla vuosina 2014 ja 2015. Molemmissa kokeissa oli 8 Ayrshire-rotuista lypsylehmää. Kokeet toteutettiin kaksinkertaisina 4x4 latinalaisina neliöinä, joissa oli neljä ruokintaa neljänä kolmen viikon jaksona. Koeasetelmat olivat 2x2 faktoriaalisia. Ensimmäisessä kokeessa faktoreina olivat säilörehun kasvilaji (nurmi tai 1:1 nurmi+härkäpapu-kevätvehnä) ja väkirehun raakavalkuaispitoisuus (175 tai 200 g/kg ka). Toisessa kokeessa faktoreina olivat valkuaistäydennys eri lähteistä (rypsirouhe tai härkäpapu), sekä näiden osittainen korvaaminen Spirulina platensis mikrolevällä. Kokeen 2 koeruokinnat olivat isonitrogeenisiä valkuaisrehujen suhteen. Kokeessa 2 kaikissa koeruokinnoissa oli sama pitoisuus kaupallista kivennäisrehua ja kokeessa 1 kivennäislisä oli täysrehuissa. Härkäpapusäilörehuseos sisälsi enemmän kivennäisaineita, mutta vähemmän hivenaineita kuin nurmisäilörehu. Härkäpavun siemen sisälsi 70 % enemmän kuparia kuin rypsirouhe. Härkäpapusäilörehuseos lisäsi eri kivennäisaineiden saantia 1-6 %, mutta vähensi hivenaineiden, kuten raudan ja mangaanin saantia 5-7 % verrattuna nurmisäilörehuun. Härkäpavun siemen lisäsi kuparin saantia 9 %, mutta pienensi magnesiumin, rikin, raudan, mangaanin ja seleenin saanteja 2-14 % verrattuna rypsirouheeseen. Härkäpavun lisääminen ruokintaan kokoviljasäilörehuna tai kokonaisena siemenenä ei vaikuttanut kivennäis- tai hivenaineiden sulavuuteen. Härkäpapusäilörehu tai härkäpavun siemen eivät eronneet merkittävästi nurmirehusta tai rypsistä hivenaineiden lähteinä. Härkäpapu ei sisältänyt mitään kivennäis- tai hivenainetta haitallisen suurta tai hälyttävän pientä määrää.
  • Lepistö, Ahti; Räike, Antti; Sallantaus, Tapani; Finér, Leena (Elsevier, 2021)
    Science of The Total Environment 780 (2021), 146627
    Brownification, caused by increasing dissolved organic carbon (DOC) concentrations is a threat to aquatic ecosystems over large areas in Europe. The increasing concentrations of DOC in northern boreal streams and lakes have attracted considerable attention with proposed important drivers such as climate, deposition and land-use, and complex interactions between them. Changes in total organic N (TON) concentrations have received less attention, even though carbon and nitrogen losses are highly related to each other. We used long-term (1990–2019) monitoring records of 12 small data-rich headwater forested catchments in a large gradient of climate and deposition. We found that total organic carbon (TOC) concentrations were significantly increasing in almost all study catchments. The mean air temperature and change in sulphate concentrations had a strong, significant correlation to TOC change-%. Both explained, alone, more than 65% of the change in TOC concentrations, and, together, up to 83% of the variation. Sulphur deposition has already decreased to low levels, our results indicate that its importance as a driver of TOC leaching has decreased but is still clearly detected, while the impact of climate warming as a driver of TOC leaching will be even more pronounced in the future. A positive correlation was found between drainage-% and increases in TON, suggesting also importance of land management. TON trends were tightly connected to changes in TOC, but not directly linked to decreasing S deposition.
  • Kupila-Ahvenniemi, Sirkka; Hankonen, Sirkka; Sivonen, Seppo (Suomen metsätieteellinen seura, 1974)
  • Jarva, Maija; Tervahauta, Arja (Suomen metsätieteellinen seura, 1989)
  • Hautojärvi, A.; Raunemaa, T.; Lappalainen, T.; Ahonen, S.; Katainen, H.-S.; Erkinjuntti, R. (Suomen metsätieteellinen seura, 1981)