Forests of Finland 2014-2018 and their development 1921-2018

We describe the methodology applied in the 12th national forest inventory of Finland (NFI12) and describe the state of Finland's forests as well as the development of some key parameters since 1920s. According to the NFI12, the area of forestry land (consisting of productive and poorly productive forest, unproductive land, and other forestry land) is 26.2 M ha. The area of forestry land has decreased from 1920s to 1960s due to expansion of agriculture and built-up land. 20% of the forestry land is not available for wood supply and 13% is only partly available for wood supply. The area of peatlands is 8.8 M ha, which is one third of the forestry land. 53% of the current area of peatlands is drained. The volume of growing stock, 2500 M m(3), is 1.7 times the volume estimated in NFI1 in the 1920s for the current territory of Finland. The estimated annual volume increment is 107.8 M m(3). The increment estimate has doubled since the estimate of NFI2 implemented in late 1930s. The annual mortality is estimated to 7 M m(3), which is 0.5 M m(3) more than according to the previous inventory. Serious or complete damage was observed on 2% of the productive forest available for wood supply. The amount of dead wood is on average 5.8 m(3) ha(-1) in productive forests. Since the NFI9 (1996-2003) the amount of dead wood has increased in South Finland and decreased in North Finland both in protected forests and forests available for wood supply (FAWS). The area of natural or almost natural forests on productive forest is 380 000 ha, out of this, 42 000 ha are in FAWS and 340 000 ha in protected forests.

Automated summary

The methodology applied in Finland's 12th national forest inventory (NFI12) and its results provide insights into the changes in forestry land area, growing stock volume, annual volume increment, and mortality rates since the 1920s. The data also highlights the importance of peatlands, the impact of drainage on peatlands, and the distribution of dead wood in productive forests. The comparison between different NFIs shows changes in dead wood amounts and natural forest areas in different regions of Finland.