Browsing by Subject "carbon"

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  • Vihanninjoki, Vesa (Finnish Environment Institute, 2014)
    Reports of the Finnish Environment Institute 41/2014
    Due to the Arctic climate change and the related diminishing of Arctic sea ice cover, the general conditions for Arctic shipping are changing. The retreat of Arctic sea ice opens up new routes for maritime transportation, both trans-Arctic passages and new alternatives within the Arctic region. Hence the amount of Arctic shipping is presumed to increase. Despite the observed development, the sailing conditions in the Arctic waters will remain challenging. Thus particular attention will be required also in the future with regard to crew, fleet and other infrastructural issues. In addition to other apparent challenges and risks, the increase in Arctic shipping will lead to an increased amount of emissions. The increased emissions may have considerable and unpredictable influences to the particularly sensitive Arctic environment. With regard to emission species, especially black carbon is presumed to have climatic sig-nificance within the Arctic context. Black carbon absorbs solar radiation very effectively, and when deposited to snow or sea ice cover, it may notably alter the radiative equilibrium of the Arctic region. The increased Arctic marine activities produce black carbon emissions, whose climate impacts are assessed in this report.
  • Vuorinne, Ilja Elias; Heiskanen, Janne; Pellikka, Petri (2021)
    Biomass is a principal variable in crop monitoring and management and in assessing carbon cycling. Remote sensing combined with field measurements can be used to estimate biomass over large areas. This study assessed leaf biomass of Agave sisalana (sisal), a perennial crop whose leaves are grown for fibre production in tropical and subtropical regions. Furthermore, the residue from fibre production can be used to produce bioenergy through anaerobic digestion. First, biomass was estimated for 58 field plots using an allometric approach. Then, Sentinel-2 multispectral satellite imagery was used to model biomass in an 8851-ha plantation in semi-arid south-eastern Kenya. Generalised Additive Models were employed to explore how well biomass was explained by various spectral vegetation indices (VIs). The highest performance (explained deviance = 76%, RMSE = 5.15 Mg ha−1) was achieved with ratio and normalised difference VIs based on the green (R560), red-edge (R740 and R783), and near-infrared (R865) spectral bands. Heterogeneity of ground vegetation and resulting background effects seemed to limit model performance. The best performing VI (R740/R783) was used to predict plantation biomass that ranged from 0 to 46.7 Mg ha−1 (mean biomass 10.6 Mg ha−1). The modelling showed that multispectral data are suitable for assessing sisal leaf biomass at the plantation level and in individual blocks. Although these results demonstrate the value of Sentinel-2 red-edge bands at 20-m resolution, the difference from the best model based on green and near-infrared bands at 10-m resolution was rather small.
  • Ravikumar, Ashwin; Larjavaara, Markku; Larson, Anne; Kanninen, Markku (2017)
    Revenues derived from carbon have been seen as an important tool for supporting forest conservation over the past decade. At the same time, there is high uncertainty about how much revenue can reasonably be expected from land use emissions reductions initiatives. Despite this uncertainty, REDD+ projects and conservation initiatives that aim to take advantage of available or, more commonly, future funding from carbon markets have proliferated. This study used participatory multi-stakeholder workshops to develop divergent future scenarios of land use in eight landscapes in four countries around the world: Peru, Indonesia, Tanzania, and Mexico. The results of these future scenario building exercises were analyzed using a new tool, CarboScen, for calculating the landscape carbon storage implications of different future land use scenarios. The findings suggest that potential revenues from carbon storage or emissions reductions are significant in some landscapes (most notably the peat forests of Indonesia), and much less significant in others (such as the low-carbon forests of Zanzibar and the interior of Tanzania). The findings call into question the practicality of many conservation programs that hinge on expectations of future revenue from carbon finance. The future scenarios-based approach is useful to policy-makers and conservation program developers in distinguishing between landscapes where carbon finance can substantially support conservation, and landscapes where other strategies for conservation and land use should be prioritized.
  • Koskiaho, Jari; Okruszko, Tomasz; Piniewski, Mikolaj; Marcinkowski, Pawel; Tattari, Sirkka; Johannesdottir, Solveig; Kärrman, Erik; Kämäri, Maria (Elsevier, 2020)
    Ecohydrology & Hydrobiology
    There exist numerous ecotechnologies for recovery and reuse of carbon and nutrients from various waste streams before they are lost to runoff. However, it remains largely unknown how growing implementation of such ecotechnologies affect nutrient emissions to surface waters at catchment scale. Here, this knowledge gap is addressed by application of SWAT model in three case study catchments draining to the Baltic Sea: Vantaanjoki (Finland), Fyrisån (Sweden) and Słupia (Poland). Sustainability analysis with Multi-Criteria Analysis was applied in the stakeholder workshops in the case study areas to assess different ecotechnology alternatives. The following ecotechnologies received the highest sustainability scores: in Vantaanjoki anaerobic digestion, based on mostly agricultural residues; in Fyrisån source-separation of wastewaters; in Słupia nutrient extraction within the wastewater treatment process. The effect of application of digestate on agricultural soils in the Vantaanjoki catchment was simulated by adjusting the model parameters describing the organic carbon content and physical properties of soil. The results showed small reductions of nutrient loads to the Gulf of Finland. Larger reductions of nutrient loads to Lake Mälaren in Sweden and the Baltic Sea in Poland were achieved as a result of the wastewater treatment upgrades. In the Fyrisån catchment, higher relative reductions were simulated for TN than TP, and in dry years than in wet years. Although the studied ecotechnologies did not show as high effectiveness in nutrient load reduction as combinations of traditional Best Management Practices reported in literature, they do have other multiple benefits including crop yield increase, electricity, heat and bio-based fertilizer production.
  • 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.
  • Cano Bernal, José Enrique; Rankinen, Katri; Thielking, Sophia (Academic Press., 2022)
    Journal of Environmental Management
    The majority of the carbon worldwide is in soil. In a river catchment, the tight relationship between soil, water and climate makes carbon likely to be eroded and transported from the soil to the rivers. There are multiple variables which can trigger and accelerate the process. In order to assess the importance of the factors involved, and their interactions resulting in the changes in the carbon cycle within catchments, we have studied the catchments of 26 Finnish rivers from 2000 to 2019. These catchments are distributed all over Finland, but we have grouped them into three categories: southern, peatland and northern. We have run a boosted regression tree (BRT) analysis on chemical, physical, climatic and anthropogenic factors to determine their influence on the variations of total organic carbon (TOC) concentration. TOC concentration has decreased in Finland between 2000 and 2019 by 0.91 mg/l, driven principally by forest ditching and % old forest in the catchment. Old forest is especially dominant in the northern catchments with an influence on TOC of 40.5%. In southern and peatland catchments, average precipitation is an important factor to explain the changes in TOC whilst in northern catchments, organic fields have more influence.
  • Neumann, Mathias; Moreno, Adam; Thurnher, Christopher; Mues, Volker; Härkönen, Sanna; Mura, Matteo; Bouriaud, Olivier; Lang, Mait; Cardellini, Giuseppe; Thivolle-Cazat, Alain; Bronisz, Karol; Merganic, Jan; Alberdi, Iciar; Astrup, Rasmus; Mohren, Frits; Zhao, Maosheng; Hasenauer, Hubert (2016)
    Net primary production (NPP) is an important ecological metric for studying forest ecosystems and their carbon sequestration, for assessing the potential supply of food or timber and quantifying the impacts of climate change on ecosystems. The global MODIS NPP dataset using the MOD17 algorithm provides valuable information for monitoring NPP at 1-km resolution. Since coarse-resolution global climate data are used, the global dataset may contain uncertainties for Europe. We used a 1-km daily gridded European climate data set with the MOD17 algorithm to create the regional NPP dataset MODIS EURO. For evaluation of this new dataset, we compare MODIS EURO with terrestrial driven NPP from analyzing and harmonizing forest inventory data (NFI) from 196,434 plots in 12 European countries as well as the global MODIS NPP dataset for the years 2000 to 2012. Comparing these three NPP datasets, we found that the global MODIS NPP dataset differs from NFI NPP by 26%, while MODIS EURO only differs by 7%. MODIS EURO also agrees with NFI NPP across scales (from continental, regional to country) and gradients (elevation, location, tree age, dominant species, etc.). The agreement is particularly good for elevation, dominant species or tree height. This suggests that using improved climate data allows the MOD17 algorithm to provide realistic NPP estimates for Europe. Local discrepancies between MODIS EURO and NFI NPP can be related to differences in stand density due to forest management and the national carbon estimation methods. With this study, we provide a consistent, temporally continuous and spatially explicit productivity dataset for the years 2000 to 2012 on a 1-km resolution, which can be used to assess climate change impacts on ecosystems or the potential biomass supply of the European forests for an increasing bio-based economy. MODIS EURO data are made freely available at ftp://palantir.boku.ac.at/Public/MODIS_EURO.
  • Vuoriheimo, Tomi; Hakola, Antti; Likonen, Jari; Brezinsek, Sebastijan; Dittmar, Timo; Mayer, Matej; Dhard, Chandra Prakash; Naujoks, Dirk; Tuomisto, Filip; The W7-X Team (2021)
    Carbon impurity transport and deposition were investigated in the Wendelstein 7-X stellarator by injecting isotopically labelled methane ((CH4)-C-13) into the edge plasma during the last plasma operations of its Operational Phase (OP) 1.2B experimental campaign. C-13 deposition was measured by secondary ion mass spectrometry (SIMS) on three upper divertor tiles located on the opposite side of the vessel to the(13)CH(4) inlet. The highest C-13 inventories were found as stripe-like patterns on both sides of the different strike lines. These high deposition areas were also analysed for their impurity contents and the depth profiles of the main elements in the layers. Layered deposition of different impurity elements such as Cr, Ni, Mo and B was found to reflect various events such as high metallic impurities during the OP1.2A and three boronizations carried out during OP1.2B.
  • Luoma, Antti (Helsingin yliopisto, 2018)
    Plantation forestry has increased dramatically in Uruguay during the past 25 years. Thus, planted forests have an increasing importance in providing other ecosystem services in addition to wood provision in landscape scale. Forest sector company UPM owns more than 250 000 hectares of Eucalyptus plantations in Uruguay. UPM seeks to enhance their systems to measure and monitor ecosystem services, to better understand sustainable provision of ecosystem services in their plantation landscapes, and to mitigate negative and maximize positive impacts. Benefits of monitoring and incorporating ecosystem services at management level include strengthened decision-making and communication, license to operate in long-term and better corporate image. Four ecosystem services were selected for analysis based on their relevance in UPM’s corporate strategy: wood provision, climate regulation, water provision and biodiversity maintenance. Provision of the ecosystem services were estimated quantitatively and compared to a pasture land baseline. Provision of ecosystem services was also linked to product level, tonne of pulp, when applicable. Data for the analysis was partly provided by UPM and partly by literature meta-analysis. Climate benefit of converting pasture to Eucalyptus is 8–31 MgC/ha or 29–115 MgCO2/ha depending on species and rotation number. Planting 40% of a micro water-shed with Eucalyptus reduces water streamflow approximately by 20–27%, while reducing streamflow of peak rainfall months by up to 40%, potentially alleviating floods. Pastures in UPM’s landscapes are well connected, but provided little core habitats. Native riparian forests are fragmented and maintain biodiversity poorly. Suggestions for future monitoring and measuring are presented. This thesis works as a waypoint for future studies of holistic ecosystem services provision in UPM assets.
  • 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.
  • 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.
  • Snelgrove, Paul V.R.; Soetaert, Karline; Solan, Martin; Thrush, Simon; Wei, Chih-Lin; Danovaro, Roberto; Fulweiler, Robinson W.; Kitazato, Hiroshi; Ingole, Baban; Norkko, Alf; Parkes, R. John; Volkenborn, Nils (2018)
    Diverse biological communities mediate the transformation, transport, and storage of elements fundamental to life on Earth, including carbon, nitrogen, and oxygen. However, global biogeochemical model outcomes can vary by orders of magnitude, compromising capacity to project realistic ecosystem responses to planetary changes, including ocean productivity and climate. Here, we compare global carbon turnover rates estimated using models grounded in biological versus geochemical theory and argue that the turnover estimates based on each perspective yield divergent outcomes. Importantly, empirical studies that include sedimentary biological activity vary less than those that ignore it. Improving the relevance of model projections and reducing uncertainty associated with the anticipated consequences of global change requires reconciliation of these perspectives, enabling better societal decisions on mitigation and adaptation.
  • Wymore, Adam S.; Johnes, Penny J.; Bernal, Susana; Brookshire, E. N. Jack; Fazekas, Hannah M.; Helton, Ashley M.; Argerich, Alba; Barnes, Rebecca T.; Coble, Ashley A.; Dodds, Walter K.; Haq, Shahan; Johnson, Sherri L.; Jones, Jeremy B.; Kaushal, Sujay S.; Kortelainen, Pirkko; López-Lloreda, Carla; Rodríguez-Cardona, Bianca M.; Spencer, Robert G. M.; Sullivan, Pamela L.; Yates, Christopher A.; McDowell, William H. (American Geophysical Union, 2021)
    Global Biogeochemical Cycles, 35(8), e2021GB006953
    A comprehensive cross-biome assessment of major nitrogen (N) species that includes dissolved organic N (DON) is central to understanding interactions between inorganic nutrients and organic matter in running waters. Here, we synthesize stream water N chemistry across biomes and find that the composition of the dissolved N pool shifts from highly heterogeneous to primarily comprised of inorganic N, in tandem with dissolved organic matter (DOM) becoming more N-rich, in response to nutrient enrichment from human disturbances. We identify two critical thresholds of total dissolved N (TDN) concentrations where the proportions of organic and inorganic N shift. With low TDN concentrations (0–1.3 mg/L N), the dominant form of N is highly variable, and DON ranges from 0% to 100% of TDN. At TDN concentrations above 2.8 mg/L, inorganic N dominates the N pool and DON rarely exceeds 25% of TDN. This transition to inorganic N dominance coincides with a shift in the stoichiometry of the DOM pool, where DOM becomes progressively enriched in N and DON concentrations are less tightly associated with concentrations of dissolved organic carbon (DOC). This shift in DOM stoichiometry (defined as DOC:DON ratios) suggests that fundamental changes in the biogeochemical cycles of C and N in freshwater ecosystems are occurring across the globe as human activity alters inorganic N and DOM sources and availability. Alterations to DOM stoichiometry are likely to have important implications for both the fate of DOM and its role as a source of N as it is transported downstream to the coastal ocean.
  • Nurmi, Juha (The Society of Forestry in Finland, 1997)
    The effective heating values of the above and below ground biomass components of mature Scots pine (Pinus sylvestris), Norway spruce (Picea abies), downy birch (Betula pubescens), silver birch (Betula pendula), grey alder (Alnus incana), black alder (Alnus glutinosa) and trembling aspen (Populus tremula) were studied. Each sample tree was divided into wood, bark and foliage components. Bomb calorimetry was used to determine the calorimetric heating values. The species is a significant factor in the heating value of individual tree components. The heating value of the wood proper is highest in conifers. Broad-leaved species have a higher heating value of bark than conifers. The species factor diminishes when the weighted heating value of crown, whole stems or stump-root-system are considered. The crown material has a higher heating value per unit weight in comparison with fuelwood from small-sized stems or wholetrees. The additional advantages of coniferous crown material are that it is a non-industrial biomass resource and is readily available. The variability of both the chemical composition and the heating value is small in any given tree component of any species. However, lignin, carbohydrate and extractive content were found to vary from one part of the tree to another and to correlate with the heating value.
  • Mäkelä, Jarmo; Arppe, Laura; Fritze, Hannu; Heinonsalo, Jussi; Karhu, Kristiina; Liski, Jari; Oinonen, Markku; Straková, Petra; Viskari, Toni (Copernicus Publ., 2022)
    Biogeosciences
    Soils account for the largest share of carbon found in terrestrial ecosystems, and their status is of considerable interest for the global carbon cycle budget and atmospheric carbon concentration. The decomposition of soil organic matter depends on environmental conditions and human activities, which raises the question of how permanent are these carbon storages under changing climate. One way to get insight into carbon decomposition processes is to analyse different carbon isotope concentrations in soil organic matter. In this paper we introduce a carbon-13-isotopespecific soil organic matter decomposition add-on into the Yasso soil carbon model and assess its functionality. The new 13C-dedicated decomposition is straightforward to implement and depends linearly on the default Yasso model parameters and the relative carbon isotope (13C/12C) concentration. The model modifications are based on the assumption that the heavier 13C atoms are not as reactive as 12C. The new formulations were calibrated using fractionated C, 13C and δ 13 measurements from litterbags containing pine needles and woody material, which were left to decompose in natural environment for 4 years. The introduced model modifications considerably improve the model behaviour in a 100-year-long simulation, where modelled δ3 is compared against fractionated peat column carbon content. The work presented here is a proof of concept and enables 13C to be used as a natural tracer to detect changes in the underlying soil organic matter decomposition.
  • Salminen, Eero-Matti (Helsingfors universitet, 2012)
    The purpose of this study was to examine the integrated climatic impacts of forestry and the use fibre-based packaging materials. The responsible use of forest resources plays an integral role in mitigating climate change. Forests offer three generic mitigation strategies; conservation, sequestration and substitution. By conserving carbon reservoirs, increasing the carbon sequestration in the forest or substituting fossil fuel intensive materials and energy, it is possible to lower the amount of carbon in the atmosphere through the use of forest resources. The Finnish forest industry consumed some 78 million m3 of wood in 2009, while total of 2.4 million tons of different packaging materials were consumed that same year in Finland. Nearly half of the domestically consumed packaging materials were wood-based. Globally the world packaging material market is valued worth annually some €400 billion, of which the fibre-based packaging materials account for 40 %. The methodology and the theoretical framework of this study are based on a stand-level, steady-state analysis of forestry and wood yields. The forest stand data used for this study were obtained from Metla, and consisted of 14 forest stands located in Southern and Central Finland. The forest growth and wood yields were first optimized with the help of Stand Management Assistant software, and then simulated in Motti for forest carbon pools. The basic idea was to examine the climatic impacts of fibre-based packaging material production and consumption through different forest management and end-use scenarios. Economically optimal forest management practices were chosen as the baseline (1) for the study. In the alternative scenarios, the amount of fibre-based packaging material on the market decreased from the baseline. The reduced pulpwood demand (RPD) scenario (2) follows economically optimal management practices under reduced pulpwood price conditions, while the sawlog scenario (3) also changed the product mix from packaging to sawnwood products. The energy scenario (4) examines the impacts of pulpwood demand shift from packaging to energy use. The final scenario follows the silvicultural guidelines developed by the Forestry Development Centre Tapio (5). The baseline forest and forest product carbon pools and the avoided emissions from wood use were compared to those under alternative forest management regimes and end-use scenarios. The comparison of the climatic impacts between scenarios gave an insight into the sustainability of fibre-based packaging materials, and the impacts of decreased material supply and substitution. The results show that the use of wood for fibre-based packaging purposes is favorable, when considering climate change mitigation aspects of forestry and wood use. Fibre-based packaging materials efficiently displace fossil carbon emissions by substituting more energy intensive materials, and they delay biogenic carbon re-emissions to the atmosphere for several months up to years. The RPD and the sawlog scenarios both fared well in the scenario comparison. These scenarios produced relatively more sawnwood, which can displace high amounts of emissions and has high carbon storing potential due to the long lifecycle. The results indicate the possibility that win-win scenarios exist by shifting production from pulpwood to sawlogs; on some of the stands in the RPD and sawlog scenarios, both carbon pools and avoided emissions increased from the baseline simultaneously. On the opposite, the shift from packaging material to energy use caused the carbon pools and the avoided emissions to diminish from the baseline. Hence the use of virgin fibres for energy purposes, rather than forest industry feedstock biomass, should be critically judged if optional to each other. Managing the stands according to the silvicultural guidelines developed by the Forestry Development Centre Tapio provided the least climatic benefits, showing considerably lower carbon pools and avoided emissions. This seems interesting and worth noting, as the guidelines are the current basis for the forest management practices in Finland.
  • Jokinen, Henri (Helsingin yliopisto, 2019)
    Dead wood includes everything between small branches and large trunks. Dead wood is created by abiotic and biotic factors like wind, lightning, competition and diseases. The amount of dead wood in Finland varies significantly between managed and natural forests. Approximately 50 % of the biomass of dead wood is carbon and thus dead wood is a notable carbon storage. Carbon may remain in dead wood for decades after the tree death. The amount of nitrogen in dead wood is small and it increases when the decay process proceeds. The aim of this study was to research the amount and quality of dead wood near the SMEAR II -station. The study also examined how the amount of carbon and nitrogen in dead wood varies between tree species and decay classes. Dead wood measurements were done at the ICOS-plots (24 pcs.) near the SMEAR II -station. At every plot there was a measurement area of 60 m2 where every piece of dead wood at the diameter of 2 cm or more was measured. Only dead wood inside the measurement area was measured. The length and top and down diameters of downed dead wood were measured. In case of standing dead wood the length and diameter at breast height were measured. The height and top diameter of stumps were measured as well. The decay class and appearance of dead wood were determined according to national forest inventory´s criteria. Based on the measurements the amount of dead wood at the plots and the whole area was calculated. Dead wood samples were taken from the plots. The samples were dried, milled and their carbon and nitrogen concentrations were analysed. The study revealed that the amount of dead wood in the study area is larger than in managed forests on average. Downed dead wood was the most common dead wood type while standing dead wood was the rarest type. The number of stumps was quite large. The most common species were Scots pine, Norway spruce and birch. The amount of dead wood varied significantly between the plots. The concentration of carbon in dead wood was on average 49 % and there were no differences between tree species and decay classes. The concentration of nitrogen was on average 0,8 % which is relatively high compared to other studies, and the concentration increased with increased decaying. There was a significant variation on nitrogen concentration between decay classes but not between tree species. This study supports other studies´ results that dead wood has an important role on carbon and nitrogen cycling in the forest.
  • Kramarenko, Dmitri (Helsingfors universitet, 2012)
    In the carbon cycle carbon is sequestrated from the atmosphere through photosynthesis in vegetation, returned into soils as litter and released into atmosphere in decomposition as carbon dioxide. In the boreal zone a large proportion of the organic carbon is bound into soil. The aim of this study was to find out how the amount of soil organic carbon (SOC) has changed in Finnish forests in last 20 years by comparing results of empirical measurements from two projects (1986-1995 and 2006). The purpose of the study was also to analyze how well the field measurements of SOC collected in two consecutive periods of time are suitable for characterization of changes in the SOC stock. The effect of soil structure, vegetation type and climatic factors on possible SOC changes were also studied. The average size of SOC stock (organic layer + mineral layer 0-40cm) in Finnish forests is 5.65 kg C m-2. About one third of SOC is in the organic layer (2.10 kg C m-2) and the rest of it is in the mineral soil (3.56 kg C m-2 ). Higher amount of SOC stock in the organic layer has been determined on plots with thicker organic layer, poor drainage and the presence of peat mosses. Higher amount of SOC in the mineral layer has been measured on plots which have a more southerly location, lower stoniness and high proportion of fine textures. Coefficients of determination in General Linear Models were between 23-61%. The average annual change of SOC (organic layer + mineral layer 0-40 cm) is +33.9 g C m-2a-1. Change in the organic layer has been +11.4 g C m-2a-1 and in the mineral soil +22.5 g C m-2a-1. The accumulation of organic carbon into the organic layer is positively correlated with the thickness of the organic layer, the southern location, pine dominance in tree layer and the age of the trees, while in the mineral soil higher carbon accumulation occurs in less stony soils and in more southern locations. Coefficients of determination in General Linear Models describing the change in SOC were low, between 11-14%. The largest positive or negative changes in SOC are in plots where the depth of the organic layer measured in two successive measurements was very different. Also, the differences in the measurements of SOC were large if the plots were drained, divided to two different sections or plots were excessively moist. Climate change and higher temperature will probably affect soil carbon sequestration positively, forecasted by using the results of the south-north gradient in which more carbon was accumulated into the soils of southern Finland. Soil monitoring research should be developed by using precise sampling methods and establishing permanent instructions for field work in order to avoid additional sources of error and to minimize variation.
  • Lahtinen, Maria; Salmi, Anna-Kaisa (2019)
    A stable isotope investigation of a large Medieval population buried in Iin Hamina, northern Finland, has been used to reconstruct palaeodiet. Iin Hamina is situated approximately 30 km away from the modern city Oulu, in close proximity to the Bothnian Bay coast and the river Ii. The material used in this study is human skeletal material from an Iin Hamina cemetery dated as 15 to 17th centuries AD and animal bones excavated in Northern Ostrobothnia from pre-industrial contexts. Stable isotope analysis of well-preserved collagen indicate that both freshwater and marine fish was the dominant protein source for the people buried at the Iin Hamina cemetery.