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Acta Forestalia Fennica vol. 75 | 1961

Category: Article

article id 7140, category Article
Päiviö Riihinen. (1963). Metsänhoidon tason vaihtelu Suomen maatilametsälöillä : tutkimus metsänhoitolautakunnittaisten erojen taloudellisista ja sosiaalisista tekijöistä. Acta Forestalia Fennica vol. 75 no. 6 article id 7140. https://doi.org/10.14214/aff.7140
  • Riihinen, ORCID ID:E-mail:
article id 7139, category Article
Päiviö Riihinen. (1963). Economic models underlying forest policy programs : an evaluation of ends and means. Acta Forestalia Fennica vol. 75 no. 5 article id 7139. https://doi.org/10.14214/aff.7139
  • Riihinen, ORCID ID:E-mail:
article id 7138, category Article
Kullervo Kuusela, Pekka Kilkki. (1963). Kasvuprosentin ja muiden metsikkötunnusten välinen yhteiskorrelaatio männiköissä. Acta Forestalia Fennica vol. 75 no. 4 article id 7138. https://doi.org/10.14214/aff.7138
English title: Multiple regression of increment percentage on other characteristics in Scots pine stands.

The objective of this study has been to discover some of the basic principles on which an increment for a large forest area might be forecast. Because the stands in a large forest area vary considerably in density and are subject to different kinds of treatment, the main interest falls on the stand characteristics which determine the increment percentage in such forest conditions as these. The material used in the study has been published earlier, it consisted of sample plots of Scots pine (Pinus sylvestris L.) stands (Nyyssönen 1954).

Increment functions are of great importance in the increment forecast for cutting budget. Because 60-80% of the variation in the increment percentage can be explained by stand characteristics in circumstances where the age of the stand is 40-130 years and the volume vary with a coefficient of variation 0.6-0.7, regression equations for increment percentage may be based on a number of sample plots smaller than in a growing stock inventory in the same conditions. It is possible to get accurate results with relatively small number of sample plots. Furthermore, the smaller amount of increment sample plots makes it possible to develop measurement techniques.

The increment functions enable study of increment as a biological process. However, conclusions about biological process on the basis of regression equations should be made with caution. Still, regression analysis is a powerful tool in yield studies.

The PDF includes a summary in Finnish.

  • Kuusela, ORCID ID:E-mail:
  • Kilkki, ORCID ID:E-mail:
article id 7137, category Article
Yrjö Roitto. (1963). Ison-Saimaan yhteisuitto-ongelma. Acta Forestalia Fennica vol. 75 no. 3 article id 7137. https://doi.org/10.14214/aff.7137
English title: Problem of co-operative floating on the Iso-Saimaa in Eastern Finland.

In Finland roundwood is floated either privately or co-operatively. In the later, a co-operative floating association is established to operate floating. The association is compulsory association of those enterprises who want to have wood floated along the floating routes of the area. It is favoured when the number of enterprises and the wood to be floated is large. In addition, costs are lower than in private floating.

Floating in Lake Saimaa area in Central Finland can be divided into Iso-Saimaa, where floating is private, and into Saimaa Water System, where floating is operated by a co-operative floating association. It has been suggested that adoption of co-operative floating in Iso-Saimaa would be to the common interest. This study aimed at finding out if co-operative floating influences the transport costs, and if co-operative floating increases competition of roundwood by forest industry companies.

According to the study, the costs of most enterprises would decrease. The total decrease in costs would amount to 65 million Finnish marks annually, about 20% less than the present costs. The change of organization would not alter the competitive relationship in buying roundwood. On the other hand, it would seem that co-operative floating would be less flexible than private floating. The management of a large organization, whose effective operation time would cover only a part of the year, would meet with some difficulties. Also, co-operative floating would reduce competition among enterprises.

The PDF includes a summary in English.

  • Roitto, ORCID ID:E-mail:
article id 7136, category Article
Aarne Nyyssönen, Yrjö Vuokila. (1963). Metsiköiden luokituksen vaikutus erisuuruisten koealojen määrään. Acta Forestalia Fennica vol. 75 no. 2 article id 7136. https://doi.org/10.14214/aff.7136
English title: The effect of stratification on the number of sample plots of different sizes.

It is necessary to study the problems related to the size, number and location of sample plots as well as to the effect of stratification. This paper, mainly concerned with the volume of the growing stock based on measurements, comprises a part of the research in progress related to the issue.

The study contains a discussion of certain problems relevant to the planning of a forest inventory on the basis of variation in the volume of the growing stock. In particular, the aim has been to give data for selection of the size and number of sample plots, and to illustrate the importance of stratification, here based principally on dominant height.

The research material comprised two forest areas of 10 ha each; measurement of the growing stock was made in units of 49 m2. Based on the data was constructed a model area embracing 4 forested strata and one non-forested stratum. The mean and standard deviations of the volumes was calculated for the forest area as a whole and for the different strata. On studying stratification, two approaches were employed to distribute the sample plots among the strata: optimum allocation and proportional allocation. The latter is simple in application, and gave for forested areas number of sample plots which did not exceed by more than 10% those obtained by optimum allocation. It is obvious that the application of stratification is worthy of consideration within forest areas which comprise parts with distinct differences. The decrease in number of plots with increasing plot size is considerably more marked within a stratified area. Thus, larger sample plots should be used in the former case than in the later. The investigations give hints on how forest inventories should be carried out. However, it has some limitations, which are discussed in the paper.

The PDF includes a summary in English.

  • Nyyssönen, ORCID ID:E-mail:
  • Vuokila, ORCID ID:E-mail:
article id 7135, category Article
Paavo Yli-Vakkuri. (1961). Kokeellisia tutkimuksia taimien syntymisestä ja ensi kehityksestä kuusikoissa ja männiköissä. Acta Forestalia Fennica vol. 75 no. 1 article id 7135. https://doi.org/10.14214/aff.7135
English title: Experimental studies on the emergence and development of tree seedlings in spruce and pine stands.

This paper aims at studying regeneration of Norway spruce (Picea abies (L.) Karst.) and Scots pine (Pinus sylvestris L.) by sowing and natural regeneration of birch (Betula sp.) in Western Finland.

Germination of spruce and pine seeds may be prevented by dryness and temperatures below the optimum for germination. In natural conditions, when temperature and moisture is insufficient for germination, the type of seedbed generally has en effect on germination result. Trenching of the seeding spots showed that root competition during the early stage of regeneration was not of decissive importance. It seemed to, however, improve the preservation of the seedlings later. It is common that it can take long before the seeds germinate, and during that time the number of viable seeds decrease strongly.

Also, the seedling stock quickly began to decrease in number after germination, especially during the first growing season and the following winter. The decrease was larger in intact vegetation than on mineral soil or in the humus layer. The emerging seedlings were destroyed by drought very easily, but their tolerance to drought improved later on.

The PDF includes a summary in English.

  • Yli-Vakkuri, ORCID ID:E-mail:

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