International requirements for national forest data will especially increase, as solutions for combating climate change and maintaining biodiversity are sought from forests.
“Celebrating the 100th anniversary, National Forest Inventory will be even more useful in the future”, says Kari T. Korhonen, principal scientist at the Natural Resources Institute Finland (Luke), who has led National Forest Inventory of Finland since 2004.
Korhonen sees that Finland’s international cooperation sets particular pressures for the production of new types of data. Currently, Finland is committed to producing national forest data for the UN’s statistics and the climate agreements, among others.
Korhonen, who steers National Forest Inventory activities from Joensuu, is most interested in the EU’s internal debate over forest policy guidance. The EU’s biodiversity strategy and forest strategy are particularly hot topics.
“The biodiversity strategy already listed a group of concrete goals for the use of forests. I expect the forest strategy to set similar goals for the direction in which forests are hoped to develop in Europe. To implement and monitor these strategies, the EU is expected to set new monitoring goals. These are very interesting times”, Korhonen says.
Finland can largely respond to questions based on international needs using previously collected data. However, even if data had already been measured, more office work should be expected.
“Whenever we are dealing with an international context, definitions may differ. How data collected in different countries can be standardised is a matter of negotiation.”
As an example of a country with different practices Korhonen would like to point out Austria.
“In Finland, all trees are measured, no matter the size. In Austria, which does have a good inventory system, the minimum diameter is 7.5 centimetres. No inventory data is available on trees below this limit.”
The role of forests and the need for accurate forest data are emphasised in public debate, whether we are talking about finances, biodiversity, recreation or adaptation to climate change.
National Forest Inventories produce data for decision-making purposes in more diverse ways. Forest damage started to be monitored in the 1980s, biodiversity in the 1990s and the volume of greenhouse gases sequestered in forests in the 2000s.
The measurement of more diverse data makes it more difficult to interpret the data. “Currently, we are, for example, investigating the link between logging and carbon emissions from the soil – something we did not tackle in any way 50 years ago”, Korhonen says.
“More and more accurate data are needed: we need to measure new things to model something new. When forests have been modelled in more detail, we can make even more complicated calculations. Although modelling calculations involve uncertainties, they are constantly improving, and we can make even better decisions on the future.”
Finland, alongside Sweden and Norway, can boast of having the world’s longest spanning time series measured in forests on a national scale.
“These time series, based on measurement data, serve to steer coffee talk towards facts”, Korhonen says.
“It may come as a surprise to many that, during modern silviculture, the proportion of deciduous trees has increased in Finland’s forests, or that current forest management practices have increased the number of old and large-sized trees. Many present comments to build completely opposite images compared with measurement data.”
Korhonen does not even absolve the scientific community. Last summer, an article was published in Nature, an esteemed science journal, presenting wild allegations of increased logging volumes in the Nordic countries, for example, based on the interpretation of satellite images alone.
“In Finland and Sweden, national forest inventory data indicates a completely opposite trend. The article was based on a complete misinterpretation of satellite images.”
Text: Heikki Hamunen
Picture on top of the page: Erkki Oksanen, Luke
Published in Finnish in Maaseudun Tulevaisuus newspaper on 22 of March 2021