Browsing by Subject "hiilidioksidi"

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  • Nygrén, Nina; Lyytimäki, Jari; Tapio, Petri (Elsevier, 2012)
    Transport Policy 24 (2012), pages 159-167
    Societies are increasingly characterised by increasing mobility of people and materials. Consequently, harmful environmental impacts of transport are likely to increase unless specific policies aimed at mitigating these impacts can be successfully implemented. Based on EU-level requirements for carbon dioxide emission reductions, a car tax reform was enacted in Finland in 2008. By using the environmental protection process (EPP) framework as a conceptual tool, we perform a quantitative content analysis of media discussion of the car tax reform. The EPP framework is an integrative tool, aimed at an overall view of the characteristics of environmental problems and mitigation measures. The results show that societal factors, emissions, measures and the potential side-effects of the reform dominated the media discussion. Short-term impacts were emphasised over longer-term perspectives in the discussion’s future-orientation. Overall, it seems that in spite of a relatively wide-ranging discussion, the media debate contributed only marginally to public understanding of the prerequisites for environmentally sustainable transport.
  • 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.
  • Carlberg, J. J. (Suomen metsätieteellinen seura, 1935)
  • Bergström, Irina (Finnish Environment Institute, 2011)
    Monographs of the Boreal Environment Research 38
    The carbon dioxide (CO2) and methane (CH4) fluxes from aquatic sediments have recently received considerable interest because of the role of these gases in enhancing climate warming. CO2 is the main end product of aerobic respiration and CH4 is produced in large amounts under anaerobic conditions. Shallow, vegetated sediments are an important source of both gases. CH4 may be transported via rhizomes and aerenchymal tissues of aquatic plants from the sediment to the atmosphere, thus avoiding oxidation in the aerated sediment surface and water column. Temperature is known to be a key factor affecting benthic CO2 and CH4 flux rates, but the interplay between other factors that may affect the fluxes from sediments is still poorly known. In order to study the spatial and temporal variability of carbon gas fluxes in boreal aquatic sediments, the area-based CO2 production rates in lake and brackish water sediments and CH4 emissions in vegetated lake littorals were measured in this work. The effects of temperature, sediment quality, plant species, zoobenthos and seasonal variation on flux rates were also estimated. The range of CO2 production rates measured in the field was 0.1–12.0 mg C m–2 h–1 and that of CH4 emission rates 0–14.3 mg C m–2 h–1. When incubated at elevated temperatures (up to 30 °C) in the laboratory, the CO2 production rates increased up to 70 mg C m–2 h–1. Temperature explained 70–94% of the temporal variation in the CO2 production in lake sites and 51% in a brackish water site. In the lake mesocosm, temperature explained 50–90% of the variation of CH4 emission. By contrast, CH4 oxidation rate was not dependent on temperature. The CH4 fluxes through the plants of six emergent and floating-leaved plant species were studied in the field (temperature range 20.4–24.9 °C). Stands of the emergent macrophyte Phragmites australis emitted the largest amounts of CH4 (mean emission 13.9 ± 4.0 (SD) mg C m-2 h–1), the mean emission rate being correlated with mean net primary production (NPP) and mean solar radiation. In the stands of floating-leaved Nuphar lutea the mean CH4 efflux (0.5 ± 0.1 (SD) mg C m–2 h–1) was negatively correlated with mean fetch and positively with percentage cover of leaves on the water surface. On a regional level, stands of the emergents P. australis and Equisetum fluviatile emitted 32% more CH4 than natural open peatland during the growing season, although their areal coverage in the study region was only 41% of that of peatland area. Climate warming will presumably increase the carbon gas emission from vegetated littorals. The model-based estimated increase of CO2 production rate in June was 29% and for CH4 emissions as much as 65% for the time interval of 110 years from 1961–1990 to 2071–2100. The results indicate that carbon gas fluxes from aquatic sediments, especially from vegetated littorals, are significant at the landscape level. They are linked to temperature but also to several other interacting factors such as e.g. water and bottom quality and ecosystem composition. Detailed investigation of the overall links between the causes and effects is urgently needed in order to understand and predict the changes caused by warming climate.
  • Iversen, L.L.; Winkel, A.; Baastrup-Spohr, L.; Hinke, A.B.; Alahuhta, J.; Baattrup-Pedersen, A.; Birk, S.; Brodersen, P.; Chambers, P. A.; Ecke, F; Feldmann, T.; Gebler, D.; Heino, J.; Jespersen, T. S.; Moe, S. J.; Riis, T.; Sass, L.; Vestergaard, O.; Maberly, S. C.; Sand-Jensen, K.; Pedersen, O. (American Association for the Advancement of Science, 2019)
    Science Vol. 366, Issue 6467, pp. 878-881
    Unlike in land plants, photosynthesis in many aquatic plants relies on bicarbonate in addition to carbon dioxide (CO2) to compensate for the low diffusivity and potential depletion of CO2 in water. Concentrations of bicarbonate and CO2 vary greatly with catchment geology. In this study, we investigate whether there is a link between these concentrations and the frequency of freshwater plants possessing the bicarbonate use trait. We show, globally, that the frequency of plant species with this trait increases with bicarbonate concentration. Regionally, however, the frequency of bicarbonate use is reduced at sites where the CO2 concentration is substantially above the air equilibrium, consistent with this trait being an adaptation to carbon limitation. Future anthropogenic changes of bicarbonate and CO2 concentrations may alter the species compositions of freshwater plant communities.
  • Amiri, Ali; Ottelin, Juudit; Sorvari, Jaana; Junnila, Seppo (IOP Publishing, 2020)
    Environmental Research Letters 15 (2020) 094076
    Although buildings produce a third of greenhouse gas emissions, it has been suggested that they might be one of the most cost-effective climate change mitigation solutions. Among building materials, wood not only produces fewer emissions according to life-cycle assessment but can also store carbon. This study aims to estimate the carbon storage potential of new European buildings between 2020 and 2040. While studies on this issue exist, they mainly present rough estimations or are based on a small number of case studies. To ensure a reliable estimation, 50 different case buildings were selected and reviewed. The carbon storage per m2 of each case building was calculated and three types of wooden buildings were identified based on their carbon storage capacity. Finally, four European construction scenarios were generated based on the percentage of buildings constructed from wood and the type of wooden buildings. The annual captured CO2 varied between 1 and 55 Mt, which is equivalent to between 1% and 47% of CO2 emissions from the cement industry in Europe. This study finds that the carbon storage capacity of buildings is not significantly influenced by the type of building, the type of wood or the size of the building but rather by the number and the volume of wooden elements used in the structural and non-structural components of the building. It is recommended that policymakers aiming for carbon-neutral construction focus on the number of wooden elements in buildings rather than more general indicators, such as the amount of wood construction, or even detailed indirect indicators, such as building type, wood type or building size. A practical scenario is proposed for use by European decision-makers, and the role of wood in green building certification is discussed.
  • Kupiainen, Kaarle Juhana; Aamaas, Borgar; Savolahti, Mikko; Karvosenoja, Niko; Paunu, Ville-Veikko (European Geosciences Union, 2019)
    Atmospheric Chemistry and Physics 19, 7743–7757
    We present a case study where emission metric values from different studies are applied to estimate global and Arctic temperature impacts of emissions from a northern European country. This study assesses the climate impact of Finnish air pollutants and greenhouse gas emissions from 2000 to 2010, as well as future emissions until 2030. We consider both emission pulses and emission scenarios. The pollutants included are SO2, NOx, NH3, non-methane volatile organic compound (NMVOC), black carbon (BC), organic carbon (OC), CO, CO2, CH4 and N2O, and our study is the first one for Finland to include all of them in one coherent dataset. These pollutants have different atmospheric lifetimes and influence the climate differently; hence, we look at different climate metrics and time horizons. The study uses the global warming potential (GWP and GWP*), the global temperature change potential (GTP) and the regional temperature change potential (RTP) with different timescales for estimating the climate impacts by species and sectors globally and in the Arctic. We compare the climate impacts of emissions occurring in winter and summer. This assessment is an example of how the climate impact of emissions from small countries and sources can be estimated, as it is challenging to use climate models to study the climate effect of national policies in a multi-pollutant situation. Our methods are applicable to other countries and regions and present a practical tool to analyze the climate impacts in multiple dimensions, such as assessing different sectors and mitigation measures. While our study focuses on short-lived climate forcers, we found that the CO2 emissions have the most significant climate impact, and the significance increases over longer time horizons. In the short term, emissions of especially CH4 and BC played an important role as well. The warming impact of BC emissions is enhanced during winter. Many metric choices are available, but our findings hold for most choices.
  • Mytty, Tuukka (Helsingfors universitet, 2013)
    Does carbon dioxide predict temperature? No it does not, in the time period of 1880-2004 with the carbon dioxide and temperature data used in this thesis. According to the Inter Governmental Panel on Climate Change(IPCC) carbon dioxide is the most important factor in raising the global temperature. Therefore, it is reasonable to assume that carbon dioxide truly predicts temperature. Because this paper uses observational data it has to be kept in mind that no causality interpretation can be made, only predictive inferences. The data is from the years 1880-2004 and consists of carbon dioxide emissions and temperature anomalies, the base period for the anomalies is 1961-1990. The main analysis method is the cointegrated VAR model but also the standard VAR model is used. The variables were tested for possible unit roots and it was found that there were unit roots present. Then the variables were tested for the cointegrating rank and here the analysis divided into three parts. One, with the assumptions that the variables are integrated of order one, a constant as a deterministic term and one cointegrating relation. Two, variables are allowed to be integrated of order two, a linear trend as a deterministic term and one cointegrating relation. Three, based on some weak evidence there was a result that variables weren’t cointegrated and the analysis could be done in differences. In the first the case it the result was that carbon dioxide doesn’t predict temperature but actually temperature predicted carbon dioxide, the second version gave the same result. In the third case neither one of the variables predicted the other one. These results go against the what is considered as the common consensus in the subject matter of climate change.
  • Tuomaala, Emilia (Helsingin yliopisto, 2022)
    Permafrost peatlands have a significant role in the global carbon cycle, as they store ca. 185 Pg of carbon. Because of the slow decomposition of organic matter, they have sequestered carbon dioxide from the atmosphere and cooled the climate for thousands of years. However, in anaerobic decomposition also methane – a strong greenhouse gas – is produced. Climate change results in changes in permafrost peatland habitats; distribution and proportional share and these changes also affect the CO2 and CH4 fluxes. In this master’s thesis I compare the net ecosystem exchange and pore water methane concentrations in different microhabitats in the Stordalen palsa mire in Abisko, Sweden. In addition, I review the reported climate change-driven habitat changes in the area and its effects on the CO2 and CH4 fluxes. My results suggest that Sphagnum sp. and Sphagnum fuscum -microhabitats were net sinks of CO2 whereas lichen-, shrub- and Eriophorum-microhabitats were net sources. These results were best explained by the proportional coverage of green vegetation, which was highest in both Sphagnum-microhabitats. No discernible differences were found between pore water methane concentrations in different habitats. Permafrost thawing has increased the occurrence of wet habitats in Stordalen. These habitat changes have increased carbon sequestration in the area but at the same time methane emissions have also increased. Because of this, the radiative forcing of the peatland has changed from negative to positive and the on-going habitat changes will likely continue in future. On a longer timespan though, the radiative forcing will likely switch back to negative as carbon sequestration increases and the effects of the methane emissions decrease.
  • Huard, David; Fyke, Jeremy; Capellán‐Pérez, Iñigo; Matthews, H. Damon; Partanen, Antti‐Ilari (John Wiley & Sons, 2022)
    The climate scenarios that form the basis for current climate risk assessments have no assigned probabilities, and this impedes the analysis of future climate risks. This paper proposes an approach to estimate the probability of carbon dioxide (CO2) concentration scenarios used in key climate change modeling experiments. It computes the CO2 emissions compatible with the concentrations prescribed by Coupled Model Intercomparison Project Phase 5 (CMIP5) and CMIP6 experiments. The distribution of these compatible cumulative emissions is interpreted as the likelihood of future emissions given a concentration pathway. Using Bayesian analysis, the probability of each pathway can be estimated from a probabilistic sample of future emissions. The approach is demonstrated with five probabilistic CO2 emission simulation ensembles from four Integrated Assessment Models (IAM), leading to independent estimates of the likelihood of the CO2 concentration of Representative Concentration Pathways (RCP) and Shared Socioeconomic Pathways (SSP). Results suggest that SSP5-8.5 is unlikely for the second half of the 21st century, but offer no clear consensus on which of the remaining scenarios is most likely. Estimates of likelihoods of CO2 concentrations associated with RCP and SSP scenarios are affected by sampling errors, differences in emission sources simulated by the IAMs, and a lack of a common experimental framework for IAM simulations. These shortcomings, along with a small IAM ensemble size, limit the applicability of the results presented here. Novel joint IAM and the Earth System Model experiments are needed to deliver actionable probabilistic climate risk assessments.
  • Juntheikki, Joni (Helsingfors universitet, 2014)
    Purpose of this thesis is to estimate the carbon sequestration potential in eucalyptus plantations in Uruguay. This study also aims to show how beneficial these plantations are for carbon sinks. The aim of this research is calculate total carbon balance in eucalyptus plantations and compare the results to degraded lands. This study is first-of-its-kind study in Uruguay, but not unique globally. The objective was to use a modeling approach to formulate the results. The methodology of this study is based to the dynamic growth model (CO2fix V3.1). Model is developed to calculate and estimate forest carbon fluxes and stocks. In this study the model was utilized for estimating how much carbon is sequestered in eucalyptus plantations and soils. In this thesis the model was used to simulate eucalyptus forest plantations that stem from numerous studies and different data. Ad hoc Excel model was generated to form calculated results from the simulated data. A separate sensitivity analysis is also formulated to reveal a possible different outcome. The framework is based on a stand-level inventory data of forestry plantations provided by the Ministry of Uruguay (MGAP) and companies. Also multiple scientific reports and previous studies were used as guidelines for simulations and results. The forest stand, yield, soil and weather data used for this study are from three different departments. There are over 700 000 hectares of different species of eucalyptus plantations in Uruguay. The theoretical framework was tested computationally with eleven simulations. CO2fix was parameterized for fast-growing eucalyptus species used in different parts of Uruguay. The model gave outputs per hectare and then this result was scaled up to the national level. This study will also estimate how much grassland (Pampa) and former pasture land could sequester carbon. Situation prior to plantation is a baseline scenario and it is compared to the expected carbon sequestration of plantations. The model is also used to calculate the effect of changing rotation length on carbon stocks of forest ecosystem (forest vegetation and soil) and wood products. The results of this study show that currently the 707,674 hectares of eucalyptus plantations in Uruguay have the potential to sequester 65 million tonnes of carbon and reduce 238 million tonnes of CO2. The calculated carbon storage is 38 and simulated 25 million tonnes of C, products are deducted from the equation. During 22 years (1990–2012) the annual carbon sequestration benefit (afforestation-baseline) without products is 1 757 847 Mg C. The results suggest that it is reasonable to establish eucalyptus plantations on degraded, grassland (Pampa) and abandoned pasture land. The implications of the results are that eucalyptus plantations in Uruguay actually enhance carbon sequestration, are carbon sinks and store more carbon than grassland and abandoned pasture land. Plantations have a vast sequestration potential and are important in mitigating of CO2 emission and effects of the climate change. The findings endorse the significance of plantations to increase carbon sinks and this role will broaden in the future. The most relevant findings of this study are that afforestation increases the soil carbon in 10-year rotation plantations by 34% (101.1>75.6) and in 12-year rotation 38% (104.4>75.6 Mg Cha-1) in a 60-year simulation. The net (afforestation-baseline) average carbon stock benefit in the soil is 25.5 Mg C ha?1 in a 60-year simulation. The (CO2Fix) model indicate that the total average carbon sequestration for eucalyptus plantations is 92.3 Mg Cha?1. The average total carbon storage ranges from 25.8–138.5 Mg Cha?1 during a 60-year simulation. The simulations show that the net annual carbon storage in the living biomass is 29.1, 25.5 (soil) and 37.6 Mg C (products) on the average scenario. There is some fluctuation in the sequestration results in other 10 simulations. Previous studies have showed that the average carbon stock for eucalyptus plantations varies from 30–60 Mg C ha-1, when soil and products are deducted. The capacity of forest ecosystems to sequester carbon in the long run could be even more strengthened if a rotation length increases. Extending rotation from 10 to 12 years increased the average soil carbon stock from 25.5 to 28.8 Mg C (by 13%) in 60 year simulation. The results also indicate that mean annual precipitation (MAP) alters the carbon sinks of the forest ecosystem. There are some limitations in this study and they are clearly explained and analyzed. Hence, most of the results are estimations. Ministry and companies need to prolong planting of trees and even intensify annual programs in order to achieve carbon sequestration targets. Further research is needed to get an estimate of the total forest ecosystem carbon storages and fluxes.
  • Mäkelä, Leena (Etelä-Savon ympäristökeskus, 2008)
    ESAra 3/2008
    Tässä selvityksessä on laskettu Etelä-Savon kuntien kasvihuonekaasupäästöt ja -tase vuonna 2005. Lisäksi on määritetty alueen energiatasetta kuvaava energiantuotanto ja -kulutus samalta vuodelta. Vastaava laskelma on tehty myös vuonna 2000. Mallin laskennassa on noudatettu IPCC:n (Intergovernmental Panel of Climate Change) metodiikkaa ja Suomen päästöinventaarioiden laskentaparametreja. Päästöt on laskettu Kuntaliiton toimittamalla kuntatason kasvihuonekaasu- ja energiatasemalli Kasvenerin avulla. Kasvihuonekaasujen (hiilidioksidi, metaani ja typpioksiduuli) aiheuttamat päästöt on laskettu erikseen seuraaville sektoreille; sähkö- ja kaukolämmöntuotanto, teollisuuden oma energiantuotanto, kuntaan ostettu sähkö, rakennusten erillislämmitys, liikenne, teollisuusprosessit, karjatalous, maanviljely, jäteveden puhdistus ja kaatopaikat. Lisäksi on tarkasteltu polttoaineiden käytöstä aiheutuvien hiilimonoksidi- ja typenoksidipäästöjä eli ns. välillisiä kasvihuonekaasuja. Tässä työssä ei ole huomioitu tuotteisiin ja palveluihin liittyvää välillistä energiankulutusta eikä tästä johtuvia kasvihuonekaasupäästöjä. Lisäksi tässä selvityksessä on laskettu maankäytön (metsät, suot ja vesistöt) aiheuttamat kasvihuonekaasupäästöt ja nielut. Nämä on laskettu kirjallisuudesta löytyvien keskimääräisten arvojen perusteella. Myös työssä esitetyt primäärienergian lähteisiin ja kulutuksiin perustuvat energiataseet on laskettu Kasvener-ohjelman avulla. Kasvihuonekaasupäästöt on laskettu sekä energiantuotannon että energiankulutuksen mukaan. Etelä-Savon kulutusperusteiset päästöt sisältävät alueelle tuotavan sähkön tuotannossa syntyneet päästöt. Nämä päästöt olivat vuonna 2005 hiilidioksidiekvivalentteina noin 1 208 500 tonnia. Tuotantoperusteiset päästöt (eivät sisällä sähköntuonnin päästöjä) olivat vuonna 2005 hiilidioksidiekvivalentteina noin 1 161 500. Vuonna 2000 vastaavat luvut olivat kulutusperusteisten päästöjen osalta noin 1 262 800 hiilidioksidiekvivalenttia ja tuotantoperusteiset noin 1 175 000 hiilidioksidiekvivalenttia. Asukasta kohden muutettuina tuotantoperusteisia päästöjä oli noin 7,2 t ja kulutusperusteisia päästöjä noin 7,5 t. Vuonna 2000 tuotantoperusteisia päästöjä oli asukasta kohden noin 7,1 t ja kulutusperusteisia noin 7,6 t. Tuotantoperusteiset päästöt ovat nousseet hiukan vuodesta 2000 vuoteen 2005 ja kulutusperusteiset puolestaan hiukan laskeneet. Etelä-Savon väkiluku on puolestaan vähentynyt samassa ajassa noin 3 %. Euroopan Unionin jäsenmaissa kasvihuonekaasupäästöt vuonna 2004 olivat keskimäärin 10,6 t/asukas, Suomessa vuonna 2005 noin 13,2 t/asukas ja vuonna 2004 Pohjois-Karjalassa 9,2 t/asukas. Verrattuna vuoteen 2000 uusimpien hakkuumäärien mukaan vuoden 2007 nieluvaikutus olisi noin 2 090 000 tonnia CO2 -ekv eli mikäli päästöjen määrä pysyy samana, jäisi nieluvaikutus päästöjen jälkeen enää aavistuksen positiiviseksi. Nielujen määrään vaikuttavat voimakkaasti hakkuumäärät sekä puuston sen hetkinen ikä. Mikäli metsiemme hakkuita lisättäisiin esimerkiksi suunnitellut 1,5 miljoonaa kuutiota vuodessa, puuston nieluvaikutus olisi enää noin 81 000 tonnia CO2 -ekv.
  • Laine, Anna M.; Lindholm, Tapio; Nilsson, Mats; Kutznetsov, Oleg; Jassey, Vincent E. J.; Tuittila, Eeva-Stiina (John Wiley & Sons Ltd, 2021)
    Journal of Ecology 109, 4 (2021), 1774–1789
    1. Most of the carbon accumulated into peatlands is derived from Sphagnum mosses. During peatland development, the relative share of vascular plants and Sphagnum mosses in the plant community changes, which impacts ecosystem functions. Little is known on the successional development of functional plant traits or functional diversity in peatlands, although this could be a key for understanding the mechanisms behind peatland resistance to climate change. Here we aim to assess how functionality of successive plant communities change along the autogenic peatland development and the associated environmental gradients, namely peat thickness and pH, and to determine whether trait trade-offs during peatland succession are analogous between vascular plant and moss communities. 2. We collected plant community and trait data on successional peatland gradients from post-glacial rebound areas in coastal Finland, Sweden and Russia, altogether from 47 peatlands. This allowed us to analyse the changes in community-weighted mean trait values and functional diversity (diversity of traits) during peatland development. 3. Our results show comparative trait trade-offs from acquisitive species to conservative species in both vascular plant and Sphagnum moss communities during peatland development. However, mosses had higher resistance to environmental change than vascular plant communities. This was seen in the larger proportion of intraspecific trait variation than species turnover in moss traits, while the proportions were opposite for vascular plants. Similarly, the functional diversity of Sphagnum communities increased during the peatland development, while the opposite occurred for vascular plants. Most of the measured traits showed a phylogenetic signal. More so, the species common to old successional stages, namely Ericacae and Sphagna from subgroup Acutifolia were detected as most similar to their phylogenetic neighbours. 4. Synthesis. During peatland development, vegetation succession leads to the dominance of conservative plant species accustomed to high stress. At the same time, the autogenic succession and ecological engineering of Sphagna leads to higher functional diversity and intraspecific variability, which together indicate higher resistance towards environmental perturbations.
  • Rutanen, Aino (Helsingin yliopisto, 2020)
    Global warming caused by the warming effect of greenhouse gases (GHGs) induces permafrost thaw, which could alter Arctic ecosystems from prominent carbon sinks to potential sources of GHG emissions when polar microorganisms become metabolically more active and have access to carbon compounds that were previously largely unavailable. Polar microbes can have significant contributions to the growing emissions of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) and therefore, studies on their metabolism are important. The aim of my study was to investigate polar microbial community composition and diversity as well as functional potential that was related to GHG-cycling in a subarctic environment with genome-resolved metagenomics. Soil cores were collected at the Rásttigáisá fell that is located in Northern Norway. After DNA extraction, ten mineral soil samples were sequenced. Metagenome-assembled genomes (MAGs) were reconstructed using either the combination of human-guided binning and automatic binning or human-guided binning only. Taxonomy was assigned to the MAGs and the functional potential of the MAGs was determined. I recovered dozens of good-quality MAGs. Notably, the MAGs from the mostly unknown phyla Dormibacterota (formerly candidate phylum AD3) and Eremiobacterota (formerly candidate phylum WPS-2) were reconstructed. There were MAGs from the following bacterial phyla as well: Acidobacteriota, Actinobacteriota, Chloroflexota, Gemmatimonadota, Proteobacteria and Verrucomicrobiota. In addition to the bacterial MAGs, MAGs from the group of ammonia-oxidizing archaea were recovered. Most of the MAGs belonged to poorly studied phylogenetic groups and consequently, novel functional potential was discovered in many groups of microorganisms. The following metabolic pathways were observed: CO2 fixation via the Calvin cycle and possibly via a modified version of 3-hydroxypropionate/4-hydroxybutyrate cycle; carbon monoxide oxidation to CO2; CH4 oxidation and subsequent carbon assimilation via serine pathway; urea, ammonia and nitrite oxidation; incomplete denitrification as well as dissimilatory nitrate reduction to ammonium. My study demonstrates how genome-resolved metagenomics provides a valuable overview of the microbial community and its functional potential.
  • Poutamo, Helinä (Helsingin yliopisto, 2019)
    Peatlands are significant pools of carbon and nitrogen. Forestry-drained peatlands have lower methane emissions than undisturbed peatlands, but emissions of carbon dioxide and nitrous oxide increase after ditching. The effect of ditching on the emissions of peat is stronger on nutrient-rich peatlands than on nutrient-poor peatlands. However, the growing vegetation and wood production form a large carbon sink. So far, forestry-drained peatlands have mainly been carbon sinks in Finland. There are 4.6 million hectares of forestry-drained peatlands in Finland. Ditching peatlands for forestry started in the beginning of the 20th century, and was on its height from 1960s to 1980s. Forestry-drained peatlands are reaching maturity now, but there is little knowledge about the effect of forest management practices on greenhouse gas emissions from forestry-drained peatlands. The purpose of this study is to investigate the effect of logging residues on emissions of carbon dioxide, methane and nitrous oxide from forestry-drained peatlands. Greenhouse gas emissions were measured from the nutrient-rich peatland Lettosuo in Tammela that was drained for forestry in 1969. In early spring of 2016, dominant pine trees were harvested to make room for spruce undergrowth. During the harvest, the harvester formed piles of logging residues on its tracks to avoid erosion of the soil. Five plots were established and measurements taken with the closed-chamber method during 2016-2017. On each of the five plots, two chamber collars were installed on the machine’s tracks, full of logging residues, and other two collars were installed outside of the tracks with little to no logging residues. In addition to greenhouse gas emissions, the dry mass of the logging residues, temperature and groundwater level were measured. Carbon dioxide emissions from residue-covered collars was measured at 0.81–0.88 g m-2 h-1. The fluxes were 1.5-2 times larger than on the control collars (0.40–0.54 g m-2 h-1). A kilogram of logging residues raised the emissions by 0.10 ± 0.01 g m-2 h-1. Compared to the dry mass of branches, the dry mass of needles increased the emissions fourfold. On plots 1-4, the collars installed in the groove of the harvester’s tracks were the only sources of methane by 0.0055 mg m-2 h-1. The methane flux of the other collars varied between -0.0035 and 0.0136 mg m-2 h-1. A kilogram of logging residues raised methane fluxes by 0.003 ± 0.001 mg m-2 h-1. Again, the effect of needles was quadruple as compared to branches. Plot #5 was investigated separately due to the Eriophorum vaginatum that had grown inside the collars. On all plots, nitrous oxide emissions didn’t significantly differ from collar to collar, even though emissions measured from logging-residue covered collars (0.20–0.30 mg m-2 h 1) were two to three times larger than on the other collars (0,10 mg m-2 h-1). Logging residues and the mechanical impact of the harvester on the peat soil increase emissions of carbon dioxide and methane. Emissions of nitrous oxide also increase, but the variance of measured emissions and the small sample size rendered the results statistically insignificant.
  • Lankinen-Timonen, Sara (Helsingin yliopisto, 2019)
    Soilla on merkittävä rooli hiilen (C) varastoinnissa sekä kasvihuonekaasujen, kuten hiilidioksidin (CO2) vaihdossa. Suoekosysteemeissä kasvit sitovat yhteytyksessään ja vapauttavat hengityksessään hiilidioksidia. Hiilidioksidia vapautuu takaisin ilmakehään lisäksi hajottajien hengityksen tuotteena. Nettomääräisesti luonnontilaiset suot sitovat hiilidioksidia, koska korkea pohjavedenpinnan taso rajoittaa maahan kertyvän orgaanisen aineen, eli turpeen hajotusta. Turpeesta vapautuvan hiilidioksidin määrä on kuitenkin muuttunut olennaisesti soiden ojituksen seurauksena, kun pohjavedenpinnan lasku on lisännyt hapellisen hajotuksen määrää turpeessa. Suomessa tehtiin runsaasti metsäojituksia erityisesti 1960–1970-luvulla. Nämä ojitetut turvemaat ovat tänä päivänä harvennushakkuiden ja kunnostusojituksen tarpeessa, mutta mittaustieto näiden toimenpiteiden välittömistä vaikutuksista hiilikaasujen vaihtoon on yhä vähäistä. Tietoa suometsien käytön ilmastovaikutuksista eri metsänhoitotoimien yhteydessä tarvitaan lisää. Tämän tutkielman tarkoitus oli selvittää vaikuttavatko harvennushakkuu ja kunnostusojitus metsäojitetulla suolla hiilidioksidivuohon ja sitä sääteleviin ympäristötekijöihin (pohjavedenpinnan taso, turpeen lämpötila). Tutkimusaineisto kerättiin Hyytiälän metsäasemalla Juupajoella sijaitsevalta metsäojitetulta suolta vuosina 2010–2013 ja 2015. Hiilidioksidivuota mitattiin suljetun kammion menetelmällä kasvillisilta mittauspisteiltä kokonaishengityksenä (RTOT) ja kasvittomilta heterotrofisena hengityksenä (RHET) seitsemällä koealalla. Harvennushakkuu tehtiin joulukuussa 2011 ja kunnostusojitus elokuussa 2012. Harvennushakkuulla ja kunnostusojituksella oli selvä vaikutus pohjavedenpinnan tasoon erityisesti ohutturpeisella koealalla. Harvennushakkuu nosti pohjavedenpintaa ja kunnostusojitus laski sitä hakkuuta edeltävälle tasolle tai sen alle. Turpeen lämpötilan suhteen toimenpiteiden vaikutus jäi vähäiseksi ja epäselväksi. Turpeen lämpötilassa ei ollut merkittäviä eroja vuosien tai koealojen välillä. Sekä turpeen lämpötila että pohjavedenpinnan taso säätelivät hiilidioksidivuota. Pohjavedenpinnan tason muutokset vaikuttivat kuitenkin voimakkaammin hiilidioksidivuohon kuin turpeen lämpötilan muutokset etenkin rehevämmillä kasvupaikoilla. Hiilidioksidivuo reagoi selvästi toimenpiteisiin rehevämmillä kasvupaikoilla. Vuotuiset ennustetut hiilidioksidivuot vaihtelivat vuosina 2011–2014 välillä 711–2414 g CO2 m-2 v-1 (RHET) ja 1604–3519 g CO2 m-2 v-1 (RTOT) kasvupaikasta riippuen. Vuotuisissa CO2-voissa oli selvää vaihtelua kasvupaikkojen välillä: rehevämmillä turvekangastyypeillä CO2-vuon määrä sekä vuosien välinen vaihtelu olivat suuremmat kuin karummilla. Harvennushakkuu ja kunnostusojitus yhdessä toteutettuna voivat tämän tutkimuksen perusteella lisätä merkittävästi hengityksestä aiheutuvaa hiilidioksidivuota metsäojitetulla suolla erityisesti rehevillä ja ohutturpeisemmilla kasvupaikoilla. Karummilla ja paksuturpeisilla kasvupaikoilla toimenpiteiden vaikutus näyttää sen sijaan jäävän vähäiseksi. Harvennushakkuu yksinään voi kuitenkin vähentää hiilidioksidivuota suon pinnasta nostaessaan pohjavedenpinnan tasoa.
  • Rautio, Mikko (Etelä-Savon ympäristökeskus, 2007)
    ESAra 1/2007
    Julkaisu sisältää tietoa Etelä-Savon ympäristökeskuksen toiminta-alueella (Etelä-Savon maakunta) aiheutuvasta ympäristökuormituksesta. Tiedot on koottu Ympäristöhallinnon ylläpitämästä Valvonta- ja kuormitustietojärjestelmästä (VAHTI), jonne ympäristölupavelvolliset vuosittain ilmoittavat tiedot mm. ilma- ja vesipäästöistä sekä jätemääristä. Raportti keskittyy vuoden 2005 tietoihin, mutta osa tiedoista on aikaisemmilta vuosilta, jos vuoden 2005 tietoja ei ole ollut saatavilla. Raporttiin on koottu tietoa myös aikaisempien vuosien kuormituksesta, jotta voidaan seurata kuormituksen kehittymistä. Ihmisen aiheuttama ympäristökuormitus Etelä-Savossa on erittäin vähäistä verrattuna muuhun Suomeen. Etelä- Savosta puuttuu lähes kokonaan suuret teollisuuslaitokset, jotka ovat suuria piste-kuormittajia. Maakunnan asukasmäärä ja –tiheys ovat pieniä verrattuna keskimäärin muuhun Suomeen, jolloin yhdyskuntien pistekuormittajat (esim. voimalaitokset ja jätevedenpuhdistamot) ovat kooltaan melko pieniä ja kuormitus vähäistä.
  • Sajaniemi, I. K. (Suomen metsätieteellinen seura, 1936)
  • Matkala, Laura (Helsingfors universitet, 2013)
    Boreal peatlands contain approximately one third of the global soil carbon and are considered net sinks of atmospheric CO2. Water level position is one of the main regulators of CO2 fluxes in northern peatlands because it controls both the thickness of the aerobic layer in peat and plant communities. However, little is known about the role of different plant functional groups and their possible interaction with changing water level in boreal peatlands with regard to CO2 cycling. Climate change may also accelerate changes in hydrological conditions, changing both aerobic conditions and plant communities. To help answer these questions, this study was conducted at a mesocosm facility in Northern Michigan where the aim was to experimentally study the effects of water levels, plant functional groups (sedges, shrubs and mosses) and the possible interaction of these on the CO2 cycle of a boreal peatland ecosystem. The results indicate that Ericaceous shrubs are important in the boreal peatland CO2 cycle. The removal of these plants decreased ecosystem respiration, gross ecosystem production and net ecosystem exchange rates, whereas removing sedges did not show any significant differences in the flux rates. The water level did not significantly affect the flux rates. The amount of aboveground sedge biomass was higher in the low water level sedge treatment plots compared to the high water level sedge plots, possibly because the lowered water level and the removal of Ericaceae released nutrients for sedges to use up.
  • Heikkinen, Johannes (Helsingin yliopisto, 2021)
    Tämän tutkielman kirjallisuuskatsaus käsittelee karbamaattien synteesimenetelmiä. Työssä käydään kevyesti läpi klassisia menetelmiä, joita ovat fosgeeniin pohjautuvat menetelmät, metallikatalysoidut reaktiot ja toisiintumisreaktiot. Moderneihin hiilidioksidiin pohjautuviin menetelmiin syvennytään tarkemmin. Läpi käydäänkin hiilidioksidin ja amiinin reaktio vedessä, orgaanisessa liuottimessa sekä superemästen avustamana. Erilaisia metodeja syklisten ja asyklisten karbamaattien valmistukseen esitellään alkyylihalideilla, epoksideilla, allyyli- ja propargyyliamiineilla sekä aminoalkoholeilla. Lopuksi tarkastellaan hieman karbamaattien atsa-Michael-reaktiota. Kokeellisessa osassa esitellään uusi stereoselektiivinen metodi 5-, 6-, ja 7-renkaisten karbamaattien valmistukseen hiilidioksidista ja aminoalkoholeista propyylifosfonianhydridin (T3P) avustamana. Karbamaattien saannot olivat hyviä.