Current issue: 53(2)

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Silva Fennica 1926-1997
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Acta Forestalia Fennica
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Articles containing the keyword 'theory'.

Category: Research article

article id 894, category Research article
Heimo Karppinen, Mika Korhonen. (2013). Do forest owners share the public’s values? An application of Schwartz’s value theory. Silva Fennica vol. 47 no. 1 article id 894. https://doi.org/10.14214/sf.894
The purpose of this study is to investigate the differences in value priorities between Finnish forest owners and the general public. A conclusion is drawn whether and to what extent value changes in society are reflected in forest owners’ values and objectives, and, finally, in their actual forestry behavior. In addition, the study highlights the differences in value priorities among forest owners in various demographic groups. The data set used in this study was based on a nationwide mail survey on Finnish non-industrial private forest owners conducted in 2009 and consisting of 2116 observations of forest owners. Schwartz’s value theory was a good fit for testing the value priorities of forest owners. The three most important values were benevolence, security and conformity, both among the forest owners and the public. Tradition was ranked the fourth most important value by the forest owners, but very low by the public. The forest owners ranked universalism slightly lower than the public in general. This difference was clearly greater when the female forest owners were compared to women in the whole population. The probability of a forest owner belonging to the Softies (high emphasis on universalism and benevolence) increased with age and was higher for the female owners and the owners with recreational or multiple objectives compared to the indifferent owners. The multiobjective owners and recreationists had relatively similar value profiles. The previous literature suggests that multiobjective owners are the most active forest owner group and that recreationists and indifferent owners are the most passive groups in their timber supply behavior. The relationship between values and forestry behavior thus remains ambiguous.
  • Karppinen, Department of Forest Sciences, P.O. Box 27, FI-00014 University of Helsinki, Finland ORCID ID:E-mail: heimo.karppinen@helsinki.fi (email)
  • Korhonen, Kämnerintie 7e 41, FI-00750 Helsinki, Finland ORCID ID:E-mail: mika.korhonen@gmx.com
article id 178, category Research article
Raili Hokajärvi, Teppo Hujala, Leena A. Leskinen, Jukka Tikkanen. (2009). Effectiveness of sermon policy instruments: forest management planning practices applying the activity theory approach. Silva Fennica vol. 43 no. 5 article id 178. https://doi.org/10.14214/sf.178
Recent and ongoing societal changes have brought about a need to foster multiple-use forestry and to strengthen customer orientation in family forestry outreach. The study assesses how forest management planning in family forest holdings could be developed to tackle these challenges. The approach introduces a new way of evaluating the effectiveness of information- and communication-based policy instruments. Here, the cultural-historical activity theory is applied in studying the interwoven practices of present-day planning and the associated advisory services targeted at landowners. The data, comprising semi-structured in-depth interviews with 19 professional planners, were qualitatively examined, and a forest management planning activity model was constructed with the emphasis placed on the inherent contradictions of planning work. As the main contradiction, the forest and the forest owner compete as objects. The aims of making the forest productive and advising the landowners towards an increased activeness motivate forest management planning but the planners feel that they lack the opportunity to respond to the needs of the landowner. A wood-production-emphasizing interpretation of the benefits to the national economy frustrates the policy goal of genuinely promoting the goals of multiple-use forestry. The conclusion drawn is that the actors engaged in forest management planning can reveal the needs for change by discussing their opinions and practical innovations. This can be done with the aid of facilitation by e.g. researchers oriented to developmental work study.
  • Hokajärvi, Oulu University of Applied Sciences, School of Renewable Natural Resources, Metsäkouluntie 4–6, FI-90650 Oulu, Finland ORCID ID:E-mail: raili.hokajarvi@oamk.fi (email)
  • Hujala, Finnish Forest Research Institute, Joensuu Research Unit, P.O. Box 68, FI-80101 Joensuu, Finland ORCID ID:E-mail:
  • Leskinen, University of Eastern Finland, Department of Geographical and Historical Studies, P.O. Box 111, FI-80101 Joensuu, Finland ORCID ID:E-mail:
  • Tikkanen, Oulu University of Applied Sciences, School of Renewable Natural Resources, Metsäkouluntie 4–6, FI-90650 Oulu, Finland ORCID ID:E-mail:
article id 347, category Research article
Gordon M. Hickey, John L. Innes. (2006). Monitoring and information reporting through regulation: an inter-jurisdictional comparison of forestry-related hard laws. Silva Fennica vol. 40 no. 2 article id 347. https://doi.org/10.14214/sf.347
In most jurisdictions, the rule of law has been the core instrument used to implement rules, regulations and restrictions relating to forests. The results of this approach have relied on the effectiveness of the system for regulating through monitoring and reporting. Despite the obvious differences in the wider operating environment of forestry internationally, issues related to globalization have increased the need for comparison. The potential impact of certain social, economic and environmental differences on the nature of monitoring and information reporting is, therefore, important to forest policy and management. The analysis presented here considered data associated with forestry-related monitoring and information reporting to provide a comparative description of certain hard-law requirements in a sample of jurisdictions. This was done to shed light on the potential for coordinated monitoring and information reporting objectives to be mandated through inter-jurisdictional hard law. Our research suggests that further comparative analysis of hard law monitoring and information reporting requirements could form a central theme in defining the ‘ground rules’ of a global forest law.
  • Hickey, University of British Columbia, Faculty of Forestry, Department of Forest Resources Management, 2045, 2424 Main Mall, UBC, Vancouver, Canada V6T 1Z4 ORCID ID:E-mail: ghickey@interchange.ubc.ca (email)
  • Innes, University of British Columbia, Faculty of Forestry, Department of Forest Resources Management, 2045, 2424 Main Mall, UBC, Vancouver, Canada V6T 1Z4 ORCID ID:E-mail:
article id 415, category Research article
Sandhya Samarasinghe, Don Kulasiri. (2004). Stress intensity factor of wood from crack-tip displacement fields obtained from digital image processing. Silva Fennica vol. 38 no. 3 article id 415. https://doi.org/10.14214/sf.415
Stress intensity factor of radiata pine (Pinus radiata) in Tangential-Longitudinal opening mode was determined from crack-tip displacement fields obtained from digital image correlation in conjunction with orthotropic fracture theory. For lower loads, experiments agreed with the linear elastic fracture theory but for higher loads, stress intensity factor and load relationship was nonlinear. For 41% of the specimens tested, tip-displacement based stress intensity factor agreed with that based on the ASTM standard formula for lower loads but deviated for higher loads closer to failure. The tip displacement plots showed that the nonlinear behaviour is due to large displacements which we attributed to large plastic deformations and/or micro-cracking in this region. The other 59% specimens showed a similar trend except that the crack-tip based stress intensity factor was consistently higher than the value obtained from the standard formula. The fracture toughness from tip displacements was larger than the standard values for all specimens and the two were related by a logarithmic function with an R2 of 0.61. The study also established that fracture toughness increases with the angle of inclination of the original crack plane to the Radial Longitudinal plane.
  • Samarasinghe, Lincoln University, P.O. Box 84, Canterbury, New Zealand ORCID ID:E-mail:
  • Kulasiri, Lincoln University, P.O. Box 84, Canterbury, New Zealand ORCID ID:E-mail: kulasird@lincoln.ac.nz (email)
article id 531, category Research article
Thomas N. Buckley, Jeffrey M. Miller, Graham D. Farquhar. (2002). The mathematics of linked optimisation for water and nitrogen use in a canopy. Silva Fennica vol. 36 no. 3 article id 531. https://doi.org/10.14214/sf.531
We develop, and discuss the implementation of, a mathematical framework for inferring optimal patterns of water and nitrogen use. Our analysis is limited to a time scale of one day and a spatial scale consisting of the green canopy of one plant, and we assume that this canopy has fixed quantities of nitrogen and water available for use in photosynthesis. The efficiencies of water and nitrogen use, and the interactions between the two, are strongly affected by physiological and physical properties that can be modeled in different ways. The thrust of this study is therefore to discuss these properties and how they affect the efficiencies of nitrogen and water use, and to demonstrate, qualitatively, the effects of different model assumptions on inferred optimal strategies. Preliminary simulations suggest that the linked optimisation of nitrogen and water use is particularly sensitive to the level of detail in canopy light penetration models (e.g., whether sunlit and shaded fractions are pooled or considered independently), and to assumptions regarding nitrogen and irradiance gradients within leaves (which determine how whole-leaf potential electron transport rate is calculated from leaf nitrogen content and incident irradiance).
  • Buckley, Environmental Biology Group, Research School of Biological Sciences, The Australian National University, GPO Box 475, Canberra City, ACT 2601, Australia and Cooperative Research Centre for Greenhouse Accounting, RSBS, ANU ORCID ID:E-mail: tom_buckley@alumni.jmu.edu (email)
  • Miller, Environmental Biology Group, Research School of Biological Sciences, The Australian National University, GPO Box 475, Canberra City, ACT 2601, Australia ORCID ID:E-mail:
  • Farquhar, Environmental Biology Group, Research School of Biological Sciences, The Australian National University, GPO Box 475, Canberra City, ACT 2601, Australia and Cooperative Research Centre for Greenhouse Accounting, RSBS, ANU ORCID ID:E-mail:
article id 530, category Research article
Graham D. Farquhar, Thomas N. Buckley, Jeffrey M. Miller. (2002). Optimal stomatal control in relation to leaf area and nitrogen content. Silva Fennica vol. 36 no. 3 article id 530. https://doi.org/10.14214/sf.530
We introduce the simultaneous optimisation of water-use efficiency and nitrogen-use efficiency of canopy photosynthesis. As a vehicle for this idea we consider the optimal leaf area for a plant in which there is no self-shading among leaves. An emergent result is that canopy assimilation over a day is a scaled sum of daily water use and of photosynthetic nitrogen display. The respective scaling factors are the marginal carbon benefits of extra transpiration and extra such nitrogen, respectively. The simple approach successfully predicts that as available water increases, or evaporative demand decreases, the leaf area should increase, with a concomitant reduction in nitrogen per unit leaf area. The changes in stomatal conductance are therefore less than would occur if leaf area were not to change. As irradiance increases, the modelled leaf area decreases, and nitrogen/leaf area increases. As total available nitrogen increases, leaf area also increases. In all the examples examined, the sharing by leaf area and properties per unit leaf area means that predicted changes in either are less than if predicted in isolation. We suggest that were plant density to be included, it too would further share the response, further diminishing the changes required per unit leaf area.
  • Farquhar, Cooperative Research Centre for Greenhouse Accounting and Environmental Biology Group, Research School of Biological Sciences, Australian National University, ACT 2601, Australia ORCID ID:E-mail: farquhar@rsbs.anu.edu.au (email)
  • Buckley, Cooperative Research Centre for Greenhouse Accounting and Environmental Biology Group, Research School of Biological Sciences, Australian National University, ACT 2601, Australia ORCID ID:E-mail:
  • Miller, Research School of Biological Sciences, Australian National University, ACT 2601, Australia ORCID ID:E-mail:
article id 563, category Research article
Timo Pakkala, Ilkka Hanski, Erkki Tomppo. (2002). Spatial ecology of the three-toed woodpecker in managed forest landscapes. Silva Fennica vol. 36 no. 1 article id 563. https://doi.org/10.14214/sf.563
The effects of landscape structure and forestry on the abundance and dynamics of boreal forest bird species have been studied widely, but there are relatively few studies in which the spatial structure and quality of the landscape have been related to the spatial ecology of bird species. In this paper, we present methods to measure territory and landscape quality for the three-toed woodpecker (Picoides tridactylus) and similar territorial forest bird species based on data from the Finnish multi-source national forest inventory and metapopulation theory. The three-toed woodpecker was studied with territory mapping within an area of 340 square km in southern Finland in 1987–2000. Altogether 195 breeding territory sites were observed. The spatial occurrence of the territories was aggregated, and the highest densities were observed in spruce-dominated old-growth forest areas. Both territory and landscape quality had significant consequences for the occurrence of the three-toed woodpecker. The spatial patterning and permanence of breeding and non-breeding territories were influenced by a combination of spatial dynamics of the species and the quality of the landscape, the latter being much influenced by forestry. The landscape-level spatial occurrence of the three-toed woodpecker in the study area may represent source-sink dynamics. The results of this paper suggest the presence of threshold values at different spatial scales, which may determine the occurrence of the three-toed woodpecker and similar species in managed forest landscapes.
  • Pakkala, Finnish Museum of Natural History, University of Helsinki, P.O. Box 17, FIN-00014 University of Helsinki, Finland ORCID ID:E-mail: timo.pakkala@helsinki.fi (email)
  • Hanski, Department of Ecology and Systematics, University of Helsinki, P.O. Box 47, FIN-00014 University of Helsinki, Finland ORCID ID:E-mail:
  • Tomppo, Finnish Forest Research Institute, Unioninkatu 40 A, FIN-00170 Helsinki, Finland ORCID ID:E-mail:

Category: Article

article id 7396, category Article
Aimo Kaarlo Cajander. (1949). Forest types and their significance. Acta Forestalia Fennica vol. 56 no. 5 article id 7396. https://doi.org/10.14214/aff.7396

This special volume of Acta Forestalia Fennica is published in memory of professor A.K. Cajander (1879-1943), who was one of the founders of the Finnish Society of Forest Science. It contains a short biography, a complete list of his literary works and one of the papers on forest types he has written.

This article contains professor A.K. Cajander’s paper on the theory of forest types in English. The article can be found in Finnish in separate PDF (article id 7695).

The idea of forest types was developed by professor Cajander first in 1904-1909, when he was working as a student in the Evo Forestry Institute. The first publication in 1909 was followed by intensive research and the findings of the investigations were published in 1929 in Acta Forestalia Fennica 29 (Metsätyyppiteoria, The theory of forest types).

When classifying forest growing sites, the purpose is to combine those having the same or approximately same yield capacity, and to separate into different classes those whose yield capacity is widely different. The article states that site quality classification is a necessity in organized forest management as it gives a basis for all forest calculations concerning with yield and profit. The principles of site classification and its meaning in forest management is discussed.

  • Cajander, ORCID ID:E-mail:
article id 7395, category Article
Aimo Kaarlo Cajander. (1949). Metsätyypit ja niiden merkitys. Acta Forestalia Fennica vol. 56 no. 4 article id 7395. https://doi.org/10.14214/aff.7395
English title: Forest types and their significance.

This special volume of Acta Forestalia Fennica is published in memory of professor A.K. Cajander (1879-1943), who was one of the founders of the Finnish Society of Forest Science. It contains a short biography, a complete list of his literary works and one of the papers on forest types he has written.

This PDF includes his article on forest types in Finnish. The translation of the text in English can be found in a separate PDF (article id 7396).

The idea of forest types was developed by professor Cajander first in 1904-1909, when he was working as a student in the Evo Forestry Institute. The first publication in 1909 was followed by intensive research and the findings of the investigations were published in 1929 in Acta Forestalia Fennica 29 (Metsätyyppiteoria, The theory of forest types).

When classifying forest growing sites, the purpose is to combine those having the same or approximately same yield capacity, and to separate into different classes those whose yield capacity is widely different. The article states that site quality classification is a necessity in organized forest management as it gives a basis for all forest calculations concerning with yield and profit. The principles of site classification and its meaning in forest management is discussed.

  • Cajander, ORCID ID:E-mail:
article id 7342, category Article
E. A. Martin Hagfors. (1939). Kritische Untersuchungen über die ökonomische Theorie der Waldwirtschaft : mit besonderer Berüksichtigung der Verhältnisse Nordeuropas. Acta Forestalia Fennica vol. 47 no. 2 article id 7342. https://doi.org/10.14214/aff.7342
English title: Critical views on the economic theory on forestry: with special consideration on Nord-European circumstances.

The article contains three parts and a summary. The first part presents the common foundations of forest economics and forest management.  The second part critically discusses the concept of sustainability and the third part takes critical view on the theories on profitability.

The author concludes by stating that the literature shows there are some old principles of forest management that always arise when the forest science progresses. The economics of forest management has been neglected in the sense that it should be acknowledged as self and not as mathematical problem as it has been handled in many theories of national economy, e.g. land rent theory. The science seems the turn back to previous findings as they are proved right again.  

The PDF contains a summary in German.

 

  • Hagfors, ORCID ID:E-mail:
article id 7258, category Article
E. A. Martin Hagfors. (1929). Über die ökonomischen Ziele bei der Bewirtschaftung der Wälder. Acta Forestalia Fennica vol. 35 no. 3 article id 7258. https://doi.org/10.14214/aff.7258
English title: On the economic objectives of the commercial use of forest.

The article has two parts: the first are the common principles of forestry and forest economics and the second part presents different theories of forest economics. The aim of the study is to find out how the best possible economic result can be achieved from forest management and use of forest resources.

The first part presents the economic foundations of forestry; the division between following the concept of economic profitability in forestry and forest management; concepts of capital and operating result in forestry; and productivity and profitability. It discusses the idea of economy as a dynamic entity instead of static.

In the second part the different economic theories related to forestry and forest economics are presented. Theory on the highest interest on forest capital, theory of sustained yield management system, land rent theory, theory on forest profitability and dynamic economic theory are discussed.      

The PDF contains a summary in Finnish.
  • Hagfors, ORCID ID:E-mail:
article id 7249, category Article
E. A. Martin Hagfors. (1929). Beitrag zur Kenntnis des Wesens der Waldwirtschaft. Acta Forestalia Fennica vol. 34 no. 36 article id 7249. https://doi.org/10.14214/aff.7249
English title: Paper on essence of forestry.

There are several competing theories about forestry: school on continuous forest management system, school on profitability of forestry and a dynamic view on economics. The article discusses the pros and cons of the different theories or viewpoints and wider the essence of forest as an economic asset.

To serve the needs of the practical forestry and the economics related to forests the forestry needs to seek for standardization in relation to growth potential of the forests and market orientation of the timber. A modern theory of forestry needs to base itself on both.  

The volume 34 of Acta Forestalia Fennica is a jubileum publication of professor Aimo Kaarlo Cajander.

  • Hagfors, ORCID ID:E-mail:
article id 5629, category Article
Risto Sievänen, Eero Nikinmaa, Jari Perttunen. (1997). Evaluation of importance of sapwood senescence on tree growth using the model Lignum. Silva Fennica vol. 31 no. 3 article id 5629. https://doi.org/10.14214/sf.a8531

The effects of two alternative formulations of sapwood senescence on the behaviour of model LIGNUM (with parameter values adjusted for Scots pine (Pinus sylvestris L.) growing southern Finland) were studied. The two alternatives were autonomous sapwood senescence assuming a maximum age for the tree ring, and sapwood senescence that is controlled by the mortality of foliage. For the latter alternative two hypothetical further mechanisms were stipulated. All the formulations were implemented in LIGNUM. Simulations were made with all model variants for fertile and poor soil conditions using high, normal and low rates of foliage mortality. The simulation results were compared against of a data set consisting of 11 open grown Scots pine trees from southern Finland. Observations of heartwood proportion were used in this study. They show that heartwood starts to increase in trees from age of approximately 20 years onwards. The simulation results showed no differences between fertile and poor soil conditions as regards heartwood formation. Of the variants of foliage-controlled sapwood senescence the one where death of sapwood in a tree segment induces sapwood senescence in the tree parts below only slightly was the best. This and the autonomous sapwood senescence corresponded equally well to the observations. In order to make more refined conclusions additional data and simulations are necessary.

  • Sievänen, ORCID ID:E-mail:
  • Nikinmaa, ORCID ID:E-mail:
  • Perttunen, ORCID ID:E-mail:
article id 5623, category Article
Harry T. Valentine. (1997). Height growth, site index, and carbon metabolism. Silva Fennica vol. 31 no. 3 article id 5623. https://doi.org/10.14214/sf.a8524

A metabolic model of height growth and site index is derived from a parametrization of the annual carbon balance of a tree. The parametrization is based on pipe-model theory. Four principal variants of the height-growth model correspond to four combinations of assumptions regarding carbon allocation: (a) the apical shoot is autonomous or (b) it is not; and (A) the specific rate of elongation of a shoot equals that of a woody root or (B) it does not. The bB model is the most general as it includes the aA, bA, and aB models as special cases. If the physiological parameters are constant, then the aA model reduces to the form of the Mitscherlich model and the bA model to the form of a Bertalanffy model. Responses of height growth to year-to-year variation in atmospheric conditions are rendered through adjustments of a subset of the model's parameters, namely, the specific rate of production of carbon substrate and three specific rates of maintenance respiration. As an example, the effect of the increasing atmospheric concentration of CO2 on the time-course of tree height of loblolly pine (Pinus taeda) is projected over 50-year span from 1986. Site index is predicted to increase and, more importantly, the shape of the site-index curve is predicted to change.

  • Valentine, ORCID ID:E-mail:
article id 5622, category Article
Christine Deleuze, François Houllier. (1997). A transport model for tree ring width. Silva Fennica vol. 31 no. 3 article id 5622. https://doi.org/10.14214/sf.a8523

Process-based tree growth models are recognized to be flexible tools which are valuable for investigating tree growth in relation to changing environment or silvicultural treatments. In the context of forestry, we address two key modelling problems: allocation of growth which determines total wood production, and distribution of wood along the stem which determines stem form and wood quality. Growth allocation and distribution are the outcome of carbon translocation, which may be described by the Munch theory. We propose a simpler gradient process to describe the carbon distribution in the phloem of conifers. This model is a reformulation of a carbon diffusion-like process proposed by Thornley in 1972. By taking into account the continuity of the cambium along the stem, we obtain a one-dimensional reaction-diffusion model which describes both growth allocation between foliage, stem and roots, and growth distribution along the stem. Distribution of wood along the stem is then regarded as an allocation process at a smaller scale. A preliminary sensitivity analysis is presented. The model predicts a strong relationship between morphology and foliage-root allocation. It also suggests how empirical data, such as stem analysis, could be used to calibrate and validate allocation rules in process-based growth models.

  • Deleuze, ORCID ID:E-mail:
  • Houllier, ORCID ID:E-mail:
article id 7199, category Article
Erik Lönnroth. (1926). Ein Dendrometer. Acta Forestalia Fennica vol. 30 no. 4 article id 7199. https://doi.org/10.14214/aff.7199
English title: Dendrometer.
Original keywords: Dendrometer; Prinzip; Theorie; Messgerät

The article presents the principle of working if a dendrometer and the mathematical theory behind it. Dendrometer is a new measuring instruments used to determine the height and diameter of a standing tree. The usability of the instruments is proofed to be very good thought there are some limitations to its use. 

  • Lönnroth, ORCID ID:E-mail:
article id 5556, category Article
Timo J. Hokkanen, Erkki Järvinen, Timo Kuuluvainen. (1995). Properties of top soil and the relationship between soil and trees in a boreal Scots pine stand. Silva Fennica vol. 29 no. 3 article id 5556. https://doi.org/10.14214/sf.a9207

One-hectare plot in a Scots pine (Pinus sylvestris L.) forest was systemically sampled for surface soil characteristics: humus layer thickness, soil carbon and nitrogen content, pH, electrical conductivity and respiration were determined from 106 samples. The effects of large trees on the plot were mapped and their joint influences at the locations of soil sampling were described as the influence potential, derived from the ecological field theory, and were calculated based on the locations and dimensions of trees.

The range of variation of soil characteristics was from three to sevenfold; no spatial autocorrelation was detected. The calculated influence potential of trees, as determined by their size and spatial distribution, was related to the spatial variation of top soil properties. Top soil properties were also related to thickness of the humus layer but they were poorly correlated with underlying mineral soil characteristics. Humus layer thickness, with the calculated influence potential of trees, may provide a means to predict top soil characteristics in specific microenvironments in the forest floor.

  • Hokkanen, ORCID ID:E-mail:
  • Järvinen, ORCID ID:E-mail:
  • Kuuluvainen, ORCID ID:E-mail:
article id 5457, category Article
Hans Roulund, Tore Skrøppa. (1991). Summary of main topics and conclusions from the meeting. Silva Fennica vol. 25 no. 4 article id 5457. https://doi.org/10.14214/sf.a15615

This paper summarises the main topics and conclusions from the joint meeting of two IUFRO working parties, S2.04-02, Breeding theory and progeny testing, and S2.02-16, Seed orchards, held in Tuusula, Finland on September 10–15, 1991. It concludes the main topics that need more research in these disciplines and future trends in the research.

  • Roulund, ORCID ID:E-mail:
  • Skrøppa, ORCID ID:E-mail:
article id 5456, category Article
Veikko Koski. (1991). Biological systems in tree breeding. Silva Fennica vol. 25 no. 4 article id 5456. https://doi.org/10.14214/sf.a15614

This issue of Silva Fennica includes the presentations given in a joint meeting of two IUFRO working parties, S2.04-02, Breeding theory and progeny testing, and S2.02-16, Seed orchardsThe sessions were held in Tuusula, Finland on September 10–15, 1991.

  • Koski, ORCID ID:E-mail:
article id 5284, category Article
Max Krott. (1986). The politics of forest bureaucracy as a subject of comparative studies. Silva Fennica vol. 20 no. 4 article id 5284. https://doi.org/10.14214/sf.a27740

Comparative analysis could offer a number of advantages in the science of forest policy. Comparisons make use of the compiled material from different countries, point to new origins and solutions of issues of forestry and allow to question the common presuppositions in the national forest policy in a critical way.

The basic requirement of fruitful comparative research is a common scientific framework. In the light of empirical-analytical theory it is more promising to compare only one factor across regions than the whole system. The forest administration could be such a suitable object of comparison in particular because it is to be found all over the world, and it has a formal and partly public organization with a number of similarities. The product of forest administration is policy. The significance of the bureaucratic behaviour in agenda setting, policy formulation, legitimating, and implementation with regard to an issue of forest policy is to be analysed.

The two significant fields of analysis, namely forest administrations and the issues of forest policy characterize the strategies of research. By making use of a collection of papers dealing with forest bureaucracy we can select countries for comparison according to the following criteria: socioeconomic context, space and time. The next step is to analyse comparatively the behaviour of the forest bureaucracy in treating a special forest issue. The explanations can be tested empirically in different countries. Perhaps the dying of the forest could be a suitable issue as an object of comparative analysis which again could enlarge our knowledge about the forest administration as a political factor.

  • Krott, ORCID ID:E-mail:
article id 7507, category Article
Reijo Mykkänen. (1994). Aspiration-based utility functions in a planning model for timber flow management. Acta Forestalia Fennica no. 245 article id 7507. https://doi.org/10.14214/aff.7507

The study presents a theory of utility models based on aspiration levels, as well as the application of this theory to the planning of timber flow economics. The first part of the study comprises a derivation of the utility-theoretic basis for the application of aspiration levels. Two basic models are dealt with; the additive and the multiplicative. Applied here solely for partial utility functions, aspiration and reservation levels are interpreted as defining piecewisely linear functions. The standpoint of the choices of the decision-makers is emphasized by the use of indifference curves. The second part of the study introduces a model for the management of timber flows. The model is based on the assumption that the decision-maker is willing to specify a shape of income flow which is different from that of the capital-theoretic optimum. The utility model comprises four aspiration-based compound utility functions.

The theory and the flow model are tested numerically by computations covering three forest holdings. The results show that the additive model is sensitive even to slight changes in relative importance and aspiration levels. This applies particularly to nearly linear production possibility boundaries of monetary variables. The multiplicative model, on the other hand, is stable because it generates strictly convex indifference curves. Due to a higher marginal rate of substitution, the multiplicative model implies a stronger dependence on forest management than the additive function. For income trajectory optimization, a method utilizing an income trajectory index is more efficient than one based on the use of aspiration levels per management period. Smooth trajectories can be attained by squaring the deviation of the feasible trajectories from the desired one.

  • Mykkänen, ORCID ID:E-mail:
article id 7586, category Article
Yrjö Kangas. (1976). Die Messung der Bestandesbonität: 1-2 Teil: Theoretische Grundlagen. Acta Forestalia Fennica no. 152 article id 7586. https://doi.org/10.14214/aff.7586
English title: Measurement of stand classification based on height over age: Part 1-2: Theoretical basis.

The article is the first part of a wider project aiming to study the measurement practices of stand’s height-over-age based classifications and to develop new methods for actually measuring the side index.  

The first part of the article presents the concepts of site indexing and discusses it with a mathematical model. The second part of the article examines the structure of site indexing system regarding the reliability of the method. Third part presents the factors affecting the method development and the fourth part discusses the possible site index classes and their characteristics.   

The PDF contains a summary in Finnish. 

  • Kangas, ORCID ID:E-mail:

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