Browsing by Subject "productivity"

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  • Tan, Jimin (Suomen metsätieteellinen seura, 1987)
  • Kulha, Niko Aleksi; Pasanen, Leena; Holmström, Lasse; Grandpre, Louis de; Kuuluvainen, Timo Tapio; Aakala, Tuomas (2019)
    Identifying the scales of variation in forest structures and the underlying processes are fundamental for understanding forest dynamics. Here, we studied these scale-dependencies in forest structure in naturally dynamic boreal forests on two continents. We identified the spatial scales at which forest structures varied, and analyzed how the scales of variation and the underlying drivers differed among the regions and at particular scales. We studied three 2kmx2km landscapes in northeastern Finland and two in eastern Canada. We estimated canopy cover in contiguous 0.1-ha cells from aerial photographs and used scale-derivative analysis to identify characteristic scales of variation in the canopy cover data. We analyzed the patterns of variation at these scales using Bayesian scale space analysis. We identified structural variation at three spatial scales in each landscape. Among landscapes, the largest scale of variation showed the greatest variability (20.1-321.4ha), related to topography, soil variability, and long-term disturbance history. Superimposed on this large-scale variation, forest structure varied at similar scales (1.3-2.8ha) in all landscapes. This variation correlated with recent disturbances, soil variability, and topographic position. We also detected intense variation at the smallest scale analyzed (0.1ha, grain of our data), partly driven by recent disturbances. The distinct scales of variation indicated hierarchical structure in the landscapes studied. Except for the large-scale variation, these scales were remarkably similar among the landscapes. This suggests that boreal forests may display characteristic scales of variation that occur somewhat independent of the tree species characteristics or the disturbance regime.
  • Walde, Manuel; Allan, Eric; Cappelli, Seraina L.; Didion-Gency, Margaux; Gessler, Arthur; Lehmann, Marco M.; Pichon, Noemie A.; Grossiord, Charlotte (2021)
    Many experiments have shown that biodiversity promotes ecosystem functioning and stability and that this relationship varies with resource availability. However, we still have a poor understanding of the underlying physiological and ecological mechanisms driving diversity effects and how they may interact with soil nutrient availability. We collected data in a grassland experiment factorially manipulating fertilization, species richness (SR), functional composition (slow-growing vs. fast-growing species) and functional diversity in resource economic traits. We measured above-ground productivity (AP), nitrogen (N) uptake, photosynthesis and water use efficiency by combining a N-15 labelling approach with productivity, gas exchange and stable isotope measurements in 3 years differing in rainfall. We found that sown SR increased AP, N uptake and photosynthesis, suggesting that SR is the most important driver of ecosystem productivity and nutrient cycling. Similarly, photosynthesis was affected by functional composition but not by functional diversity. Water use efficiency was reduced by sown SR for communities dominated by slow-growing species but not for communities dominated by fast-growing species. Fertilization increased productivity, N uptake and water use efficiency. The positive effects of high SR on ecosystem functions were independent of fertility levels. Synthesis. Our results provide evidence that high species richness in temperate grasslands could enhance productivity and reduce the negative impacts of drought events. Multiple factors and community characteristics are important in driving enhanced ecosystem functioning in biodiverse grasslands and seem to affect functioning and stability through different mechanisms.
  • Morrison, Catriona A.; Butler, Simon J.; Robinson, Robert A.; Clark, Jacquie A.; Arizaga, Juan; Aunins, Ainars; Balta, Oriol; Cepak, Jaroslav; Chodkiewicz, Tomasz; Escandell, Virginia; Foppen, Ruud P. B.; Gregory, Richard D.; Husby, Magne; Jiguet, Frederic; Kålås, John Atle; Lehikoinen, Aleksi; Lindström, Ake; Moshøj, Charlotte M.; Nagy, Karoly; Nebot, Arantza Leal; Piha, Markus; Reif, Jiri; Sattler, Thomas; Skorpilova, Jana; Szep, Tibor; Teufelbauer, Norbert; Thorup, Kasper; van Turnhout, Chris; Wenninger, Thomas; Gill, Jennifer A. (2021)
    Wildlife conservation policies directed at common and widespread, but declining, species are difficult to design and implement effectively, as multiple environmental changes are likely to contribute to population declines. Conservation actions ultimately aim to influence demographic rates, but targeting actions towards feasible improvements in these is challenging in widespread species with ranges that encompass a wide range of environmental conditions. Across Europe, sharp declines in the abundance of migratory landbirds have driven international calls for action, but actions that could feasibly contribute to population recovery have yet to be identified. Targeted actions to improve conditions on poor-quality sites could be an effective approach, but only if local conditions consistently influence local demography and hence population trends. Using long-term measures of abundance and demography of breeding birds at survey sites across Europe, we show that co-occurring species with differing migration behaviours have similar directions of local population trends and magnitudes of productivity, but not survival rates. Targeted actions to boost local productivity within Europe, alongside large-scale (non-targeted) environmental protection across non-breeding ranges, could therefore help address the urgent need to halt migrant landbird declines. Such demographic routes to recovery are likely to be increasingly needed to address global wildlife declines.
  • Lehtonen, Veli-Matti (Svenska handelshögskolan, 2007)
    Economics and Society
    Tutkimuksessa selvitetään, edistääkö Suomen valtionhallinnossa tuotettava henkilöstötilinpäätösinformaatio henkilöstöprosesseihin perustuvan henkilöstöstrategian tehokasta toteuttamista. Tutkimuksen uutuusarvo alan kansainvälisen tutkimuksen kentässä perustuu laaja-alaiseen tarkastelunäkökulmaan. Tämän mahdollisti tutkimuskohteena olevasta ilmiöstä käytössä oleva monipuolinen, yhtenäisiin käsitteisiin perustuva ja useita vuosia koskeva henkilöstötilinpäätöksen tunnuslukuaineisto. Aikaisempien tutkimusten usein yksittäisiin tekijöihin perustuvasta analyysistä poiketen, tutkimuksella selvitettiin henkilöstön johtamiseen ja tuloksellisuuteen sidoksissa olevien tekijöiden vaikutuksia laajoina kokonaisuuksina, koskien kaikkia henkilöstön johtamisprosesseja. Tutkimus avaa uusia näköaloja henkilöstöinformaation hyväksikäytölle henkilöstön eri johtamisprosesseissa, jotka liittyvät saumattomasti organisaation toimintaan ja kokonaisjohtamiseen. Käytetty henkilöstön johtamisprosessikeskeinen tarkastelukulma auttaa ymmärtämään henkilöstön osaamisen, motivaation, työhyvinvoinnin, johtamisen ja palkinnan yhteyksiä sekä toisiinsa että organisaation pitkäjänteiseen toimintaan ja tuloksellisuuteen. Tutkimuksen keskeinen tavoite on motivoida johtoa, esimiehiä ja HR -ammattilaisia entistä enemmän hyväksikäyttämään henkilöstöön liittyvää analysoitua tietoa henkilöstöstrategioiden teon ja käytäntöön viennin, johtamisen ja henkilöstösuunnittelun apuvälineenä.
  • Roth, Florian; Karcher, Denis B.; Radecker, Nils; Hohn, Sonke; Carvalho, Susana; Thomson, Timothy; Saalmann, Franziska; Voolstra, Christian R.; Kurten, Benjamin; Struck, Ulrich; Jones, Burton H.; Wild, Christian (2020)
    Following coral mortality in tropical reefs, pioneer communities dominated by filamentous and crustose algae efficiently colonize substrates previously occupied by coral tissue. This phenomenon is particularly common after mass coral mortality following prolonged bleaching events associated with marine heatwaves. Pioneer communities play an important role for the biological succession and reorganization of reefs after disturbance. However, their significance for critical ecosystem functions previously mediated by corals, such as the efficient cycling of carbon (C) and nitrogen (N) within the reef, remains uncertain. We used 96 carbonate tiles to simulate the occurrence of bare substrates after disturbance in a coral reef of the central Red Sea. We measured rates of C and dinitrogen (N-2) fixation of pioneer communities on these tiles monthly over an entire year. Coupled with elemental and stable isotope analyses, these measurements provide insights into macronutrient acquisition, export and the influence of seasonality. Pioneer communities exhibited high rates of C and N(2)fixation within 4-8 weeks after the introduction of experimental bare substrates. Ranging from 13 to 25 mu mol C cm(-2) day(-1)and 8 to 54 nmol N cm(-2) day(-1), respectively, C and N(2)fixation rates were comparable to reported values for established Red Sea coral reefs. This similarity indicates that pioneer communities may quickly compensate for the loss of benthic productivity by corals. Notably, between 40% and 85% of fixed organic C was exported into the environment, constituting a vital source of energy for the coral reef food web. Our findings suggest that benthic pioneer communities may play a crucial, yet overlooked role in the C and N dynamics of oligotrophic coral reefs by contributing to the input of new C and N after coral mortality. While not substituting other critical ecosystem functions provided by corals (e.g. structural habitat complexity and coastal protection), pioneer communities likely contribute to maintaining coral reef nutrient cycling through the accumulation of biomass and import of macronutrients following coral loss. A freePlain Language Summarycan be found within the Supporting Information of this article.
  • Virtanen, Marianna; Elovainio, Marko (2018)
    Modern work life is characterized by constant change, reorganizations, and requirements of efficiency, which make the distribution of resources and obligations, as well as justice in decisionmaking, highly important. In the work life context, it is a question not only of distributing resources and obligations, but also of the procedures and rules that guide the decisionmaking in the organization. Studies of these rules and procedures have provided the basis for a new line of research that evaluates leadership and social relationships in working communities; that is, distributive, procedural, and relational justice. This review follows the development of research on organizational justice from its origins in early social and motivational psychological theories to its establishment as a major line of research in modern work and organizational psychology. The adverse consequences of injustice include poor team climate, reduced productivity and well-being, and work-related illnesses.
  • Ala-Varvi, Tuomas (Helsingfors universitet, 2014)
    To achieve the appointed goals set in the national climate and energy strategy it is important to launch biomass into markets more effectively. In addition to biomass from clearing sites energy wood needs to be procured from young stands. First thinnings have been neglected to great extent in Finland mainly because of low profitability. The targets have been achieved only once during last decade. Expanding energy wood procurement to young stands increases the need for resources. Therefore more effective operating machines should be developed. The challenge is in launching these prototypes into testing and commercial markets. Fixteri Ltd. has developed a whole-tree bundler in order to enhance harvesting of small-diameter energy wood from young stands. This method is meant to reduce transportation costs through load compaction. The aim of this research was to study the productivity of cutting and bundling of whole-trees using Fixteri FX15a bundling unit and to clarify the competitiveness of the whole production chain compared to rival methods. The harvesting was studied trough video analyze in order to detect factors limiting the productivity. 35 whole-tree bundles were produced in young Scots pine stand. An average weight and volume of the bundle were 502.5 kg and 463 dm³. It took 3.38 min to produce one bundle. FX15a bundling unit was fitted to Logman 811FC base machine. Accumulating Nisula 280E+ felling head was used. An average performance per effective working hour of 9.74 m3 was recorded when average volume of removal was 37.3 dm3. The operator used multi-tree cutting effectively in average 3.1 whole-trees per work load. The share of multi-tree cutting was 96 percent. The performance of prototype FX15 was significantly lower than the performance of FX15a. The performance of 5.07 and 5.86 m³/h0 were recorded when average volumes of removed trees were 28.4 and 41.1 dm³. It was observed that the productivity of FX15a was higher compared to the harvesting of undelimbed trees when average volume of removed trees was less than 70 dm3. Harvesting and off-road transportation of whole tree bundles was more profitable when average volume of removal was under 95 dm3. Total costs of wood chip supply chain were lower compared to harvesting of undelimbed trees when average volume of removal was less than 85 dm3. Total costs of wood chip supply chain were higher compared to harvesting of undelimbed trees regardless of average volume of removed trees when FX15 bundling unit was used. When includung the possible energy subsidies (max 30 %) for whole-tree bundling and pre-clearance-related additional costs for harvesting of undelimbed trees into account the potential number of harvesting sites increases significantly. Drying the bundles plays an important role since high moisture content in the bundles after road side storing may endanger the competitiveness of the whole supply chain when bundles are burned to produce energy. Although bundling whole-trees seems to be a competitive alternative in harvesting small-diameter energy wood there are still several questions unanswered. The method should be studied in greater depth by varying harvesting conditions and machine operators. Also the potential of on-road transport and bundle features needs further study.
  • Muhonen, Olli (Helsingfors universitet, 2012)
    Forest energy harvesting has increased significantly in recent years. The extraction of forest energy is usually done with conventional forwarders. The productivity of extraction work is, however, quite poor due to a low material density, which results in a small load size. The objective of the study was to increase the productivity of forest energy extraction via solutions that increase the load size. The first method that was studied involved widening the load space hydraulically. The other solution was based on compressing the load with hydraulically tiltable stakes. The study was conducted as a development study. The field studies were carried out in the summer and autumn of 2011 on harvesting sites managed by Metsähallitus and Metsäliitto in the Jyväskylä region. The study material comprises a total of 139 loads. There was a significant difference in raw density between the logging residues and stump pieces for the widening and compressing load space solutions. For this reason, it does not make sense to compare the two load space solutions to each other. The analyses were based on the reported load scale tonnes. Both load space alternatives increased the load size by 20-30 per cent depending on the assortment. For logging residues, the increase in efficient hour productivity for extraction was 13 per cent and for stump pieces it was 30 per cent. With the compressing load space, the efficient hour productivity for full trees increased by 17 per cent. For logging residues, the increase was 5 per cent and for stump pieces it was 12 per cent. Compression was not a successful method for stump pieces and even for logging residues the benefits were mainly based on the increased load space. Compressing the load is mainly beneficial when extracting full trees. The project was carried out together with Osuuskunta Metsäliitto (now Metsä Group), Metsä-Multia Oy and Ponsse Oyj. The modelling work was done by Metsäteho Oy. This study shows results of Metsähallitus project “Maastokuljetuksen kehittäminen”. The project is part of the EffFibre (Value through Intensive and Efficient Fibre Supply) research and development programme coordinated by Forestcluster Ltd.
  • Kellomäki, Seppo; Hänninen, Heikki; Kolström, Taneli (Suomen metsätieteellinen seura, 1988)
  • Rodríguez-Puente, Paula; Säily, Tanja; Suomela, Jukka (2022)
    This paper tracks stylistic variation in the use of two roughly synonymous suffixes, the Romance -ity and the native -ness, during the Early Modern English period. We seek to verify from a statistical viewpoint the claims of Rodríguez-Puente (2020) , who reports on a decrease of -ness in favour of -ity in registers representative of the speech-written and formal-informal continua at that time. To this end, we develop new methods of statistical and visual analysis that enable diachronic comparisons of competing processes across subcorpora, building upon an earlier method by Säily and Suomela (2009) . Our results confirm that -ity gained ground first in written registers and then spread towards speech-related registers, and we are able to time this change more accurately thanks to a novel periodisation. We also provide strong statistical support indicating that the proportion of -ity was significantly higher in legal registers than in other registers.
  • Kuryk, Lukasz; Moller, Anne-Sophie W.; Vuolanto, Antti; Pesonen, Sari; Garofalo, Mariangela; Cerullo, Vincenzo; Jaderberg, Magnus (2019)
    Oncolytic adenoviruses can trigger lysis of tumor cells, induce an antitumor immune response, bypass classical chemotherapeutic resistance strategies of tumors, and provide opportunities for combination strategies. A major challenge is the development of scalable production methods for viral seed stocks and sufficient quantities of clinical grade viruses. Because of promising clinical signals in a compassionate use program (Advanced Therapy Access Program) which supported further development, we chose the oncolytic adenovirus ONCOS-401 as a testbed for a new approach to scale up. We found that the best viral production conditions in both T-175 flasks and HYPERFlasks included A549 cells grown to 220,000 cells/cm(2) (80% confluency), with ONCOS-401 infection at 30 multiplicity of infection (MOI), and an incubation period of 66 h. The Lysis A harvesting method with benzonase provided the highest viral yield from both T-175 and HYPERFlasks (10,887 +/- 100 and 14,559 +/- 802 infectious viral particles/cell, respectively). T-175 flasks and HYPERFlasks produced up to 2.1 x 10(9) +/- 0.2 and 1.75 x 10(9) +/- 0.08 infectious particles of ONCOS-401 per cm(2) of surface area, respectively. Our findings suggest a suitable stepwise process that can be applied to optimizing the initial production of other oncolytic viruses.
  • Rasi, Janne (Helsingfors universitet, 2011)
    In this research, the productivity change of piglet production on ProAgria Annual Pig Accounting farms (Finnish pig farms exploiting this particular advisory service) is measured from 2003 to 2008, using Fisher productivity index. Moreover, an exact decomposition method is applied in order to obtain a more detailed picture of factors contributing to productivity change. The examined components are changes in technology, technical efficiency, allocative efficiency, scale efficiency and price effect. Indices are formed in two ways: as aggregated indices and geometric means of farmlevel indices. The two indices provide almost identical average annual productivity growth rates, 2.7 % and 2.8 %, respectively, although the growth patterns slightly differ. Scale efficiency is found to be the most important factor contributing to production growth. Aggregated scale efficiency improves by 1.6 % per annum and the mean scale efficiency by 2.1 % per annum. Another component having a remarkable effect on productivity growth is technical efficiency change. Both aggregated and mean index rise by 1.4 % per annum. On the contrary, technological change is slightly negative, on average -0.1 % per year. However, annual changes are noteworthy. Both allocative efficiency change and price effect have little impact on productivity change. Growing average number of sows seems to be a major cause contributing to productivity change, seeing that it is closely connected with improving scale efficiency. Regressive technological change is an alarming result because technological change is the most important element evoking productivity growth in the long term.
  • Simula, Markku (Suomen metsätieteellinen seura, 1983)
  • Piekkola, Joel (Helsingin yliopisto, 2017)
    Foreign direct investment (FDI) saw a large increase in the EU in the years 1990–2015. A significant and contested topic in economic and industrial policy and a continuing interest to researchers has been the productivity effect of this increased foreign presence on host economies. Theories of economic growth and industrial organization predict a role for FDI, or the increased presence of multinational enterprises, as a catalyst of knowledge diffusion and other productivity effects. Findings from empirical literature support the existence of productivity effects from FDI within industry and through vertical linkages across industries. There is also support in the literature for the role of absorptive capacity as necessary for host country firms to benefit from knowledge diffusion. The scope of this study is to measure first the effect of FDI on productivity and secondly the role of absorptive capacity in mediating this effect. Data from Eurostat is extracted to construct a sample of output, factor inputs and FDI for aggregated industry level data for the years 2008–2012. Absorptive capacity is measured in three categories of intangible assets: research and development (RD), information and communications technology (ICT) and organizational competencies (OC). A production function approach with fixed effects is used to estimate the impact of FDI on productivity. The main findings are that an increase in foreign presence has a positive contemporaneous effect on productivity within industry, but a negative effect through vertical forward linkages. The results from the main specification imply that a 10 % increase in FDI is associated with a 0.5 % increase in productivity within industry and a -0.34 % decrease in customer industries. Absorptive capacity or technology gap in terms of intangible assets is closely related to the presence of these productivity effects. The finding of a positive effect of FDI on productivity within sector is consistent with knowledge spillovers or other positive factors such as increased competition. The negative effect in customer sectors may be explained by adjustment and transaction costs from the breaking down of existing domestic supply chains. The results indicate that FDI is associated with productivity gains within industry, but negative effects on productivity dominate through vertical forward linkages in the short term. From an industrial and economic policy standpoint, FDI is not unambiguously beneficial for productivity of domestic industries, but more research is needed to assess long-term effects and the economic implications for the EU as a whole.
  • Pohjonen, Veli; Pukkala, Timo (Suomen metsätieteellinen seura, 1988)
  • Svedäng, Henrik; Savchuk, Oleg P; Villnäs, Anna; Norkko, Alf; Gustafsson, Bo; Wikström, Sofia A.; Humborg, Christoph (2022)
    Hypoxia is presently seen as the principal driver behind the decline of the former dominating Eastern Baltic cod stock (EBC; Gadus morhua). It has been proposed that both worsening conditions for reproduction and lower individual growth, condition, and survival are linked to hypoxia. Here, we elucidate the ecological envelope of EBC in terms of salinity stratification, oxygen content, and benthic animal biomasses, and how it has affected EBC productivity over time. The spawning conditions started deteriorating in the Gotland Deep in the 1950s due to oxygen depletion. In contrast, in the Bornholm Basin, hydrographic conditions have remained unchanged over the last 60 years. Indeed, the current extent of both well-oxygenated areas and the frequency of hypoxia events do not differ substantially from periods with high EBC productivity in the 1970s–1980s. Furthermore, oxygenated and therefore potentially suitable feeding areas are abundant in all parts of the Baltic Sea, and our novel analysis provides no evidence of a reduction in benthic food sources for EBC over the last 30 years. We find that while reproduction failure is intricately linked to hydrographic dynamics, a relationship between the spread of hypoxia and the decline in EBC productivity during the last decades cannot be substantiated.