Browsing by Subject "forestry"

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  • Nyyssönen, Aarne (Suomen metsätieteellinen seura, 1959)
  • Kuusela, Kullervo (Suomen metsätieteellinen seura, 1979)
  • Solberg, Birger (Suomen metsätieteellinen seura, 1986)
  • Simula, Markku (Suomen metsätieteellinen seura, 1985)
  • Järveläinen, Veli-Pekka; Riihinen, Päiviö (Suomen metsätieteellinen seura, 1979)
  • Riihinen, Päiviö (Suomen metsätieteellinen seura, 1981)
  • Elovirta, Pertti (Suomen metsätieteellinen seura, 1979)
  • Mälkönen, Eino; Paavilainen, Eero (Suomen metsätieteellinen seura, 1985)
  • Metz, Aino-Marjatta (Suomen metsätieteellinen seura, 1986)
  • 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.
  • Koljonen, Kauko (Suomen metsätieteellinen seura, 1983)
  • Junttila, Samuli; Kaasalainen, Sanna; Vastaranta, Mikko; Hakala, Teemu; Nevalainen, Olli; Holopainen, Markus (2015)
    Global warming is posing a threat to the health and condition of forests as the amount and length of biotic and abiotic disturbances increase. Most methods for detecting disturbances and measuring forest health are based on multi- and hyperspectral imaging. We conducted a test with spruce and pine trees using a hyperspectral Lidar instrument in a laboratory to determine the capability of combined range and reflectance measurements to investigate forest health. A simple drought treatment was conducted by leaving the harvested trees outdoors without a water supply for 12 days. The results showed statistically significant variation in reflectance after the drought treatment for both species. However, the changes differed between the species, indicating that drought-induced alterations in spectral characteristics may be species-dependent. Based on our results, hyperspectral Lidar has the potential to detect drought in spruce and pine trees.
  • Rinkinen, Ilmo (Suomen metsätieteellinen seura, 1968)
  • de Wit, Heleen A.; Lepistö, Ahti; Marttila, Hannu; Wenng, Hannah; Bechmann, Marianne; Blicher-Mathiesen, Gitte; Eklöf, Karin; Futter, Martyn N.; Kortelainen, Pirkko; Kronvang, Brian; Kyllmar, Katarina; Rakovic, Jelena (Wiley, 2020)
    Hydrological Processes 34, 25 (2020)
    Agricultural, forestry-impacted and natural catchments are all vectors of nutrient loading in the Nordic countries. Here, we present concentrations and fluxes of total nitrogen (totN) and phosphorus (totP) from 69 Nordic headwater catchments (Denmark: 12, Finland:18, Norway:17, Sweden:22) between 2000 and 2018. Catchments span the range of Nordic climatic and environmental conditions and include natural sites and sites impacted by agricultural and forest management. Concentrations and fluxes of totN and totP were highest in agricultural catchments, intermediate in forestry-impacted and lowest in natural catchments, and were positively related %agricultural land cover and summer temperature. Summer temperature may be a proxy for terrestrial productivity, while %agricultural land cover might be a proxy for catchment nutrient inputs. A regional trend analysis showed significant declines in N concentrations and export across agricultural (−15 μg totN L−1 year−1) and natural (−0.4 μg NO3-N L−1 year−1) catchments, but individual sites displayed few long-term trends in concentrations (totN: 22%, totP: 25%) or export (totN: 6%, totP: 9%). Forestry-impacted sites had a significant decline in totP (−0.1 μg P L−1 year−1). A small but significant increase in totP fluxes (+0.4 kg P km−2 year−1) from agricultural catchments was found, and countries showed contrasting patterns. Trends in annual concentrations and fluxes of totP and totN could not be explained in a straightforward way by changes in runoff or climate. Explanations for the totN decline include national mitigation measures in agriculture international policy to reduced air pollution and, possibly, large-scale increases in forest growth. Mitigation to reduce phosphorus appears to be more challenging than for nitrogen. If the green shift entails intensification of agricultural and forest production, new challenges for protection of water quality will emerge possible exacerbated by climate change. Further analysis of headwater totN and totP export should include seasonal trends, aquatic nutrient species and a focus on catchment nutrient inputs.
  • Haltia, Olli; Simula, Markku (Suomen metsätieteellinen seura, 1988)
  • Nieminen, Mika; Sarkkola, Sakari; Hasselquist, Eliza Maher; Sallantaus, Tapani (Kluwer Academic Publishers, 2021)
    Water, Air, & Soil Pollution 232 (2021), 371
    Contradictory results for the long-term evolution of nitrogen and phosphorus concentrations in waters discharging from drained peatland forests need reconciliation. We gathered long-term (10–29 years) water quality data from 29 forested catchments, 18 forestry-drained and 11 undrained peatlands. Trend analysis of the nitrogen and phosphorus concentration data indicated variable trends from clearly decreasing to considerably increasing temporal trends. While the variations in phosphorus concentration trends over time did not correlate with any of our explanatory factors, trends in nitrogen concentrations correlated positively with tree stand volume in the catchments and temperature sum. A positive correlation of increasing nitrogen concentrations with temperature sum raises concerns of the future evolution of nitrogen dynamics under a warming climate. Furthermore, the correlation with tree stand volume is troublesome due to the generally accepted policy to tackle the climate crisis by enhancing tree growth. However, future research is still needed to assess which are the actual processes related to stand volume and temperature sum that contribute to increasing TN concentrations.
  • Saarni, Matti (Helsingin yliopisto, 2019)
    Climate change affects the human habitat and the mechanics that cause this scientific phenomenon are somewhat well known. This study examines how forest policy, agricultural policy and environmental policy can control the mechanisms that cause climate change. The material of the study consists of interviews of 12-13 Finnish experts, each representing one of the previously mentioned sectors. Each of the experts have been asked 13-14 questions about the importance of climate change mitigation, as well as the mechanisms by which agriculture and forests affect the climate and how climate change should be considered in environmental policy. The data was collected between October 8th and November 8th of 2019. This was in five weeks after the IPCC 1,5-degree climate report was published. A series of topics was constructed from the answers, and they are meant to be used as topics to be discussed in the Finnish 2019 parliamentary election. In addition, on how important scientific academics see the control of climate change, they were also asked how critical climate change is. The interview material is stored in the Finnish Social Science Data Archive (www.fsd.uta.fi) The experts’ answers to the importance of controlling climate change were almost unanimous and considered to be highly important. Carbon sink and storage were considered the most effective methods to control climate change. According to the results, the study proposes topics that should be discussed in politics and when a person wants to advance the control of climate change in forest, agriculture and environment politics. Political decisions are often based on value judgement, which again are based on the information of different methods efficacy. The results that are discussed in this study are not the only options, but they give guidelines and reasons for discussions related to effective choices. Forest policies should recognize the effects of forest industry to the development of carbon sink and storage. Forest industries prerequisite for operation and decision making in addition to considering employment and export industry, must also consider the effect for Finland’s net carbon emissions. Activities which lengthen the forest rotation time would have multiple positive benefits and increase forest carbon storage. Agricultural politics should broaden the discussion to reach food politics. Consumption habits have big effect on agricultural production structure and it can be directed by many ways. The structure of agricultural production should also be considered from the emission point of view, because the land use is substantially large and changes in production can affect Finland’s emission in a scale, that would have large effect on our nations net carbon emissions. To strengthen carbon sinks, landowners should have compensation mechanism methods, that increase carbon sinks, and which are combined to the size of the carbon storage. In environmental policy climate change must be paid more attention and governmental boundaries must not intervene significant decision making. The strengthening of the role of Ministry of the Environment and adding co-operation between different ministries supports the decision making regarding environmentally positive issues.
  • Kuusela, Kullervo (Suomen metsätieteellinen seura, 1959)
  • Abrego, Nerea; Norberg, Anna; Ovaskainen, Otso (2017)
    1. The identification of traits that influence the responses of the species to environmental variation provides a mechanistic perspective on the assembly processes of ecological communities. While much research linking functional ecology with assembly processes has been conducted with animals and plants, the development of predictive or even conceptual frameworks for fungal functional community ecology remains poorly explored. Particularly, little is known about the contribution of traits to the occurrences of fungal species under different environmental conditions. 2. Wood-inhabiting fungi are known to strongly respond to habitat disturbance, and thus provide an interesting case study for investigating to what extent variation in occurrence patterns of fungi can be related to traits. We apply a trait-based joint species distribution model to a data set consisting of fruit-body occurrence data on 321 wood-inhabiting fungal species collected in 22 460 dead wood units from managed and natural forest sites. 3. Our results show that environmental filtering plays a big role on shaping wood-inhabiting fungal communities, as different environments held different communities in terms of species and trait compositions. Most importantly, forest management selected against species with large and long-lived fruit-bodies as well as late decayers, and promoted the occurrences of species with small fruit-bodies and early decayers. A strong phylogenetic signal in the data suggested the existence of also some other functionally important traits than the ones we considered. 4. We found that those species groups that were more prevalent in natural conditions had more associations to other species than species groups that were tolerant to or benefitted from forest management. Therefore, the changes that forest management causes on wood-inhabiting fungal communities influence ecosystem functioning through simplification of interactive associations among the fungal species. 5. Synthesis. Our results show that functional traits are linked to the responses of wood-inhabiting fungi to variation in their environment, and thus environmental changes alter ecosystem functions via promoting or reducing species with different fruit-body types. However, further research is needed to identify other functional traits and to provide conclusive evidence for the adaptive nature of the links from traits to occurrence patterns found here.