it Is best for the climate to let our forests be left, to grow and sequester carbon? Or should we pursue an active forestry and felling, so that we can replace as much fossil-based products as possible?
the Question has long been discussed, now the latest on the DN Review. But the issue is not quite as simple as it is most commonly produced in the debate. It is not about a simple choice between harvesting or allowing to grow on. It is also about how to harvest, how the wood supply is used and on the time horizon.
The last is not the least crucial. We know that we have a few decades on us to reduce emissions of greenhouse gases drastically. Otherwise, we risk to pass the critical so-called ”tipping points”, where self-reinforcing processes in nature which massive skogsdöd or the melting of the permafrost leading to the continued and uncontrollable heating. In this situation, short-term effects of different skogsskötselstrategier at least as important as the long-term.
in a forest that may age naturally eventually subsides, and thus reduces the sequestration of carbon. But it is equally true that today’s production forests are felled long before this happens.
They would be able to continue to be effective carbon sinks for decades. To reduce logging by 10 per cent in the Swedish forests would increase kolinlagringen by 60 percent by the year 2030. No other changes in forest management give so large effects on the carbon balance in such a short time.
In the northern coniferous forests are a large part of the up the coal storage tied up in the soil. If the forest is harvested and the ground becomes bare released a large part of this carbon through degradation processes.
for a new skogsgeneration to compensate for kolförlusten. The logging of old-growth forests can thus not be justified by the climate, even in a longer time horizon.
for The same reason is the clear-cuts problematic. A weapon is a source of carbon up to 20 years after harvesting, and it takes another couple of decades for a new skogsgeneration to bind the corresponding amount of carbon.
the climate effect therefore becomes positive first 30-40 years after a clear-cutting. Stamvisa logging practices, where no greater surface area is laid bare at the same time, is much better from a climate point of view.
in skogsnäringens klimatbudget is substitution – that is to say that the forest raw material is used to replace fossil fuels and materials that are energy-intensive and fossilkrävande to produce, primarily steel and cement. The substitution effect is real and important for the climate, but it does not mean that increased production automatically leads to increased substitution and thus the positive effects of climate change.
today will be less than one-fifth of the timber that is taken out of the Swedish forests timber with a long service life. About half goes to pulp, and the manufacture and use of paper is generally negative from a climate point of view, even if the paper is recycled for energy.
References to figures and facts in the text are available in the report ”to Chop or protect?” , published by the Swedish society for nature conservation and WWF 2011.