Articles containing the keyword 'puuntuotanto'

The planning of timber production in a forestry unit is divisible into two phases. In the first phase, planning provides the decision-maker with a number of possible timber production policies; these policies define the production possibility boundary. After the decision-maker has chosen one of these policies, planning moves to the second phase, in which a detailed programme is prepared with a view to meeting the requirements of the timber production policy accepted. The paper indicates one possibility of solving these two tasks simultaneously. In the first phase, the solution of the primal linear programming problem is employed and in the second phase the respective dual or shadow price solution.

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• Kilkki, E-mail: pk@mm.unknown
• Pökälä, E-mail: rp@mm.unknown
• Siitonen, E-mail: ms@mm.unknown

The study deals with economic significance of forest landscape planning models used in regional planning in Finland. The »judge»-method is used among professional foresters working on private forestry boards in Southern Finland to define their view of what would be moderate level of costs of landscape management for private forest owners. A sample of 154 forest professionals working in district forestry boards in Southern Finland was sent a sociological questionnaire.

It was possible to form three hierarchical moderation classes by statistical grouping of judgement distributions. Prolongations in rotation ages and restrictions concerning ditching of forested bogs, forest read building and clear-cutting were considered the most immoderate models. Rather or wholly insignificant were evaluated such management models, which mean restrictions in »old fashioned» methods or which are already used in practice.

The PDF includes a summary in English.

• Lovén, E-mail: ll@mm.unknown

About one million hectares of forests are fertilized annually in Finland. The goal of the present study was to find out, by means of calculations, how the profitability of forest fertilization varies with variations in the stage of development of tree crops, the quality of the site and its geographical location. Calculations concerned bot fertilization of forests in mineral soil sites and in drained peatlands. The study is a part of a larger project concerning the order of profitability of different forest improvement measures in different conditions. The problems dealt with in this study were approached from the point of view of national economy.

On the basis of two empirical materials it is shown that there is a high correlation between the stand growth percentages before and after the fertilization. Applying the results to existing yield tables the authors calculate benefit/cost ratios showing the stage of development of the stand, the quality of the site and its geographical location. According to the results, fertilization is more profitable in sites of medium fertility than on poor sites. Profitability decreases rather fast from south to north and with decreasing timber prices. 

The PDF includes a summary in English.

• Keltikangas, E-mail: mk@mm.unknown
• Seppälä, E-mail: ks@mm.unknown

The article is a report of a study tour of five Finnish foresters in Germany on September 27 – October 2. 1971. As in most industrial countries, the recreation use of forests is rapidly expanding and, therefore, its needs are considered in the management of forests. Two examples of intensively used recreation forests are described, Schönbuch near Stuttgart and the Bavarian Forest National Park at the Czechoslovakian border. These forests are effectively used for both timber production and recreation at the same time. Some other effects of urbanization on forests also are discussed in the article.

The PDF includes a summary in English.

• Mikola, E-mail: pm@mm.unknown

Annual variations in wood utilization makes it complicated to estimate the balance between wood utilization and wood production of forests. According to the article, the balance is unsustainable especially in the private forests in the southern part of Finland. The annual wood utilization of the country was 37.3 million m³ in 1913, and the annual wood production 35.2 million m³, according to a report of a committee that was appointed to find methods to prevent overcutting. The committee suggested legislation to forbid forest devastation. Also the growth of the forests could be increased, if the forests are well managed, the article argues. To prove this, the potential wood production capacity is estimated for the municipalities of Viipuri, Mikkeli and Kuopio, and compared to the present wood production and wood utilization of the area.

The PDF includes a German summary.

• Ilvessalo, E-mail: yi@mm.unknown

The aim of the present study was to describe the forest types of Finnish mineral forest lands as a uniform whole in the light of stand development and wood production.

The study shows that it has been possible to work out uniform age-based development series for different stand characteristics for forest types on mineral forest lands in Finland. There is generally a clear difference in the development series of various stand characteristics and their average values between different forest types. The exceptions in a few places have been explained as depending on certain factors. The differences between adjacent forest types in order of their quality are of varying magnitude, thus differing from a schematic site quality classification obtained through calculation. Consequently, each forest type has its own development series with regard to the stand characteristics.

The number of forest types in the whole country is rather high. However, the different forest types are limited to different parts cf the country in such a way that there is no need for more than 5–6 forest types and 4 northerly sub-forms (-types) in each region, except in the border areas between the regions. In Finland the forest types have been the basis of forest site classification in forest research and practical forestry over a period of half a century. In pointing out the necessity of further study of forest types, Cajander has stressed the examination of differences in the compositions of vegetation between different classes of density of tree-stand and building up average descriptions of vegetation in such classes in young, middle-age and old stands. The same may be caused by some other factors which also are of essential influence to the composition of the vegetation.

The PDF includes a summary in English.

• Ilvessalo, E-mail: yi@mm.unknown
• Ilvessalo, E-mail: mi@mm.unknown