Sebastian Kirppu is a loud voice in the Swedish forest debate.

He is loved by the environmental movement but nonetheless appreciated by the forest companies.

The World Wide Fund for Nature chose him as the environmental hero of the year in 2011 and a few years later he was named the listeners' own summer talker in P1.

After many years as a biologist at the County Administrative Board in Dalarna, Sebastian Krippu today devotes himself full-time to trying to save the natural forests that remain in Sweden from felling.

Wants to stop deforestation

- The forest industry is running out of our real forests, says Sebastian Kirppu.

The forest is a very important ecosystem.

Planted trees can never replace the natural forests.

By taking an inventory of forests in Sweden and registering red-listed species, Sebastian Kirppu is trying to stop the logging of the forest industry in the remaining natural forests (see fact box).

However, the forest industry does not agree with Sebastian Kirppu that the forest is threatened or that biodiversity deteriorates when the natural forest decreases in Sweden.

Watch the whole world of Science "The battle for the forest - Sweden's last forests" on Monday 20 September at 20.00 on SVT2 or already now on SVT Play

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