The Multi-Source National Forest Inventory of Finland – methods and results 2013

Abstract

This report presents the methods and results of the Finnish multi-source forest inventory corresponding to year 2013. In addition to field data, satellite images, digital map data and other georeferenced data were used. The main purpose of the article is to make multi-source forest inventory results available for the users and to help the users to understand the principles of the methods and advantages and limitations of the products. The field data originate from the 11th Finnish National Forest Inventory from years 2009 to 2013. The field data have been computationally updated to the date 31 July, 2013. The satellite images where from years 2012 – 2014. The basic features of the improved k-NN, ik-NN, estimation method are described.

The results are presented by the regions of the Public Service unit of the Finnish Forest Centre and within the regions by municipalities, the boundaries as on 1.1.2014. The estimates are given, for example, for land areas, areas of tree species dominance, age, and development classes of stands and often separately for forests available for wood supply. The mean volume and total volume estimates are given in many different ways: by tree species and by timber assortments for forest land, and combined forest land and poorly productive forest land and also for forests available for wood supply, as well as by age and development classes. The biomass estimates are given, in addition to the total biomass estimates, by tree species groups in young thinning stands in which the first commercial thinning was proposed for the first 5-year period, separately for stem and bark and branches and foliage. The biomass estimates of mature forests are presented separately for branches, foliage and stem residuals, and stumps and large roots by tree species groups. These biomass estimates are given separately for land available for wood supply.

All presented results can be employed in calculating forest resource estimates also for regions larger than municipalities. The error sources for the estimates as well as the reliability of the estimates are briefly discussed in Section 3.4.4 and Chapter 5.